牦牛、牧民源大肠杆菌分离鉴定、耐药基因检测、PFGE分析及耐药性传递的研究
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摘要
牦牛是藏区牧民的最重要生产和生活资料,牦牛的大肠杆菌病在牧区普遍存在。在其他地区随着抗生素的不断使用,大肠杆菌耐药性问题已越来越严重。但是在色达藏区,海拔在3500米以上,由于气候寒冷,路途遥远,条件简陋,采样极为不便,对牦牛、牧民的大肠杆菌耐药性及相关性的研究还未见报道。
本论文针对藏区牦牛、牧民源大肠杆菌进行分离鉴定、耐药性的传播,对磺胺药、氟苯尼考耐药基因等问题,开展了系列研究工作,取得以下结果：
1、藏区牦牛、牧民源大肠杆菌分离、血清学鉴定及16S rRNA分析
从四川甘孜色达藏区9个不同乡镇的牧场,采集了具有牦牛210份粪便样品及同牧场的90份鼻腔拭子,进行采集、接种、保存条件摸索,对分离大肠杆菌进行生化学、血清学和致病性鉴定,抽取40株分离菌株作16sRNA分析。结果表明,采用80%甘油加30%脱脂牦牛奶作保护剂,可将接种成功率从10%提高到70%,菌种能保存到一周以上。共分离出株114牦牛源大肠杆菌和70株牧民源大肠杆菌。有98株牦牛源大肠杆菌菌的血清型被鉴定出来,分属24种血清型,其中有9种优势血清型占了60%的比例。有58株牧民源大肠杆菌的血清型被鉴定出来,分属12种血清型,其中有6种优势血清型占了62.8%的比例。鉴定出了22株牦牛源为致病性大肠杆菌,有20株的血清型鉴定出来,其中O78、O26、O111所占的比例最高,分别为18.2%、13.6%、13.6%,为致病性大肠杆菌的优势血清型。16S rRNA分析,这些细菌都与登录的大肠杆菌同源性为98-99%。进化树结果表明,四川甘孜色达藏区牧民源的与牧民源大肠杆菌聚为一类,牦牛源与牦牛源大肠杆菌也聚为一类。
该研究首次建立了一套在高海拔、高寒条件下采样、分离、保存细菌的简单实用方法,该方法的建立为在当地开展细菌的科研工作铺下了的技术基石。鉴定了四川甘孜色达藏区牦牛致病性大肠杆菌的优势血清型。首次用16S rRNA鉴定了四川甘孜色达藏区牦牛、牧民的大肠杆菌,研究结果为进一步研究藏区牦牛源大肠杆菌提供了基础材料。
2、四川甘孜色达藏区牦牛、牧民源大肠杆菌对15种常用抗生素的MIC测定及比较
采用药物平板稀释法对四川甘孜色达藏区114株牦牛源和70株牧民源大肠杆菌进行15种抗菌药的MIC值测定,然后对结果进行的比较分析。结果表明,四川甘孜色达藏区牦牛源大肠杆菌对磺胺甲基异嗯唑、磺胺嘧啶、氟苯尼考的耐药性最高,分别为44%、40.4%、11.4%；对其他抗生素的耐药性低：分别为阿莫西林8.78%、氨苄西林6.14%、庆大霉素3.5%、链霉素1.75%；对新霉素、多西环素、土霉素、诺氟沙星、环丙沙星、萘啶酸、壮观霉素、头孢噻呋都敏感。四川甘孜色达藏区牧民源大肠杆菌对磺胺嘧啶和SMZ的耐药性最高,分别为57.1%和51.4%。而对其他抗生素的耐药性相对较低,从高到低分别氨苄西林22.9%、阿莫西林25.7%、链霉素20%、壮观霉素14.3%、庆大霉素11.4%、土霉素11.4%、头孢噻夫11.4%、萘啶酸11.4%、诺氟沙星8.57%、多西环素5.71%、氟苯尼考4.3%、环丙沙星2.86%、新霉素0%。比较牦牛源与牧民源大肠杆菌的耐药性发现：a、牧民源大肠杆菌的耐药性比牦牛源的比例高,种类多。b、两种来源的大肠杆菌都对磺胺药的耐药性在所有抗菌药中最高。c、在牧民不使用氟苯尼考的情况下,却检测出3株牧民源大肠杆菌对该药产生抗性。本研究首次对四川甘孜色达藏区的牧民、牦牛进行耐药性平行检测和比较分析数据,未见在同一环境中采样,对比分析牦牛与牧民源大肠杆菌耐药性的研究报道。该研究为治疗当地的大肠杆菌病提供了科学指导,为耐药性研究提供了更全面的资料。3、四川甘孜色达藏区牦牛、牧民源大肠杆菌对磺胺类和氟苯尼考耐药基因的PCR检测
为检测四川甘孜色达藏区大肠杆菌主要耐药表型的耐药基因,在单重PCR方法的基础上,建立了检测磺胺耐药基因Sul1.Sul2和Sul3的三重PCR方法。利用此方法分别对50株牦牛源大肠杆菌的耐磺胺药物的基因进行检测,结果发现,在耐磺胺的50株菌中,基因阳性率为94%。其中携带基因型Sul1,Sul2,Sul1+Sul2的比例分别为36%,52%,6%。对40株牧民源大肠杆菌中,基因阳性率为92.5%。其中携带基因型Sul1,Sul2,Sul3,Sul1+Sul2,Sul1+Sul3的比例分别为42.5%,27.5%,7.5%,12.5%,2.5%。比较牦牛源与牧民源的磺胺耐药基因发现,牧民源大肠杆菌的磺胺药耐药基因型比牦牛的多两种,基因种类多Su13。本研究在国内首次对牧区人和动物磺胺耐药基因分布比较进行比较,为研究人与动物的耐药基因库提供资料。4、用脉冲场凝胶电泳PFGE对牦牛、牧民相同耐药基因型的菌株的分析研究
为了研究同一个牧场里,牦牛和牧民之间是否存在耐药菌株的相互传播。本实验挑选26株耐药大肠杆菌,分为两组,每组13株菌,携带相同的耐药基因(Sull或flor),分离于两个牧场,来源不同宿主。采用脉冲场凝胶电泳(PFGE)进行分子分型和QantityOne软件进行菌株聚类分析。
结果发现,在第一组携带磺胺耐药基因sull的13株大肠杆菌可分成12个PFGE谱型,其中含有一个克隆系,菌株牧民源C2与C4之间的相似系数达到0.9。在第二组,携带有氟苯尼考耐药基因(flor)13株菌可分成8个PFGE谱型,含有三个克隆系。其中一个克隆系里牧民源菌株B3与牦牛源菌株B12、B13具有0.88和0.93的相似系数。这些数据表明了在同一个牧场内,牧民与牧民、牦牛与牧民、牦牛与牦牛之间都存在着相同PFGE分子型的相同耐药谱菌株,提供了耐药菌株水平传播的线索。与国内外的其它类似的研究比较,本实验在所选的对象上具有独特性,首次采用PFGE研究在藏区特殊生产和生活模式下的人和牛的耐药性关系,为保障牦牛产品安全和人类健康提供科学依据。5、携带磺胺耐药基因和氟苯尼考耐药基因大肠杆菌的转化试验和接合性试验
挑选有特别耐药性的19株菌进行分组。A组：牦牛源大肠杆菌株7株,携带有flor基因,对磺胺甲基异嗯唑敏感。B组：牧民源大肠杆菌12株,携带有Sull或Sul2基因,对氟苯尼考敏感。对所有细菌进行质粒提取,电泳分析质粒图谱；采用Ca2+转化法把各菌株的质粒转化到受体菌E.coli JM109中,然后挑选转化子,测MIC值,提取质粒,用PCR检测耐药基因；将所有菌与受体菌E.coli C00进行接合试验,并测定了产生接合子的时间。结果表明,每株菌都检测到多条大小不等的质粒DNA条带,质粒获得率为100%,质粒分子量为0.4×103～90.0×103bp。在A组7类质粒中,有4类质粒转化成功；在B组12类质粒中有6类质粒成功转化；总的转化率为52.6%。在接合试验中,发现质粒转化不成功的菌株都没有与受体菌接合成功,在含耐氟苯尼考耐药基因质粒的4株牦牛源大肠杆菌中有2株接合成功；在含耐磺胺药基因质粒的6株牧民源大肠杆菌中有5株接合成功：发生接合转移的时间为3h～6h；总的接合率为36.8%。
本实验在实验室证明了耐药性能通过质粒的转化和细菌的接合传播,揭示了耐药性通过质粒传播的比例与速度,为控制耐药性的传播提供了科学资料。同时,鉴定到了2株含有携带flor基因质粒的牦牛源供体菌A12、A17,携带Sul1、Sul2基因质粒的5株牦牛源供体菌B1、B7、H1、D3, H5,为进一步开展天然大肠杆菌耐药质粒传递的研究提供了素材。
本研究在四川甘孜色达四川甘孜色达藏区对分离自牦牛、牧民的大肠杆菌进行了致病性鉴定、血清学鉴定、MIC值检测,检测了主要耐药品种的耐药基因,用PFGE分析了同牧场中牦牛与牧民之间耐药菌株的关系,检测了耐药质粒对耐药性的传递特性,为指导当地藏民科学用药,有效防治大肠杆菌等细菌性疾病,保障牦牛产品安全,防制耐药性泛滥,保护人类健康提供了科学依据。
Because of adverse weather condition, distant far-flung and poor condition in Serta County with high altitude and extremely cold climate, there is no study on E. coli of Yak and herdsman in Serta County.Yaks are the most important to production material and living material for Tibetans. Yak E. coli disease is widespread in the pastoral area. As antibacterial is used widely, the problem of drug-resistance increased seriously. Because of the transmission of resistance, it was difficult to cure E. coli disease clinically. In order to get current state of resistance for yak and herdsman in Serta County Tibetans, and the mechanism of resistance transmission, the works had been launched as follows:
1. E.coli isolated and serotype identification and 16S rRNA analysis
210 samples of yaks faces and 90 human nasal swab were collected from 9 pastures in Serta County Plateau. The conditions were selected for inoculum and conservation of stains. The isolates were identified by biologic character,serotype and pathogenicity, which of 40 stains were identified by 16sRNA. The results showed that survival rate could be raised from 10% to 80% by taking 80% Glycerin and 10% skimmed milk as protective agent.114 E.coli stains of yak and 70 E.coli stains of herdsman were isolated.
The O serotype was identified by 165 kind's single factor E.coli O antisera. Results showed that 98 stains were identified of yak in 114. The E.coli strains of yak fell into 24 serotype groups of which the O101 (12.3%)、O2 (9.6%)、O68 (7.0%). O132 (7.0%)、O78 (5.3%)、O171 (5.3%)、O22 (4.4%)、O142 (4.4%)、O165 (4.4%) were predominant, accounted for 60%.58 stains were identified of herdsman in 70. E.coli strains of herdsman fell into 12 serotype groups of which the O81 (14.3%)、 030 (11.4%).05(11.4%)、0165(8.6%)、0132(8.6%)、O101(8.6%)were predominant, accounted for 62.8%. Serotype of yak was more than herdsman. And there was 7 same serotype between yak and herdsman, including 0132、O101、O15、08、078、0171、017, accounted for 37.5%(13/70). The pathogenicity of stains was checked by challenge assays for mice. Results showed that 22 strains were pathogenic to mice identified.20 strains isolated were identified by O serotype, but 2 strains were not. O78、O26、O111 were accounted for 18.2%、13.6%、13.6%, respectively. The serotype of 078、O26、0111 were predominant of pathogenic E.coli, accounted for 50%. The serotype of pathogenic E.coli of yak was identified firstly, which was important to produce vaccine for pathogenic yak E. coli.
40 stains from herdsman and yak were amplified for 16S rRNA and sequenced. All sequences of 40 stains were blasted in GenBank. Results showed that homology of the isolates were 98-99% with other E.coli. And phylogenetic tree was constructed. Results showed that stains between herdsmen clustered in the same group and that stains between yaks clustered in the same group, too. The results showed the genetic relationship of E.coli from Tibetan Area and others.
2. MIC testing and comparation of E.coli of yak and herdsman to 15 antibiotic in common use.
The MIC of 114 strains of yak and 70 strains of herdsman from 9 pastoral areas were examined for their susceptibility to 15 antimicrobial agents by drugs dilution-plate method. The results of antimicrobial susceptibility test were analyzed according to the standard procedure advised by NCCLS. The results showed that sufisomezole, sulfadiazine and florfeniol may be the most resistant antimicrobial agents tested in this study of yak, accounted for 44%、40.4%、11.4%, respectively. The resistant rate of stains from yak was low to other antibiotics. The resistant rate from high to low was amoxicillin (8.78%)、ampicillin(6.14%)、gentamicin(3.5%)、streptomycin(1.75%).All stains from yak were 100% sensitive to neomycin, doxycycline, terramycin, norfloxacin, ciprofloxacin, nalidixic acid, spectinomycin, ceftiofur sodium. The resistant rate of stains from herdsman was 57.1% and 51.4% to sulfadiazine and SMZ, respectively. The followed antimicrobial agents were ampicillin(22.9%), amoxicillin(25.7%), streptomycin(20%), spectinomycin(14.3%), terramycin(11.4%), ceftiofur sodium(11.4%), norfloxacin(8.57%), doxycycline(5.71%), florfeniol(4.3%), ciprofloxacin(2.86%), Neomycin(0%). In summary, by comparing resistance of yak with herdsman, we can draw the conclusions:1. the resistance of herdsman was more serious than yak's in this study; 2. the sulfonamide-resistance was highest in all the antimicrobial agents; 3. the florfeniol-resistance was detected in 3 strains of herdsman, while florfeniol was prohibited in human to treatment of the diseases.
The results of drug sensitivity test of E.coli from Serta County were help to cure E. coli disease. At the same time, the results were useful to parallel examination and data analysis for yak and herdsman, understand the problem of resistance overall.
3. Detection of PCR for sulfonamide-resistance genes and florfeniol-resistance gene of E.coli of yak and herdsman
In order to detected resistance gene of E.coli in Sertar County in Tibetan pastoral area, the multi-PCR for Sul1, Sul2 and Sul3 gene and simple PCR for flor gene were established. By the multi-PCR method,50 strains of yak and 40 strains of herdsman sulfonamide-resistant isolates were checked. Results showed that sulfonamide-resistance was different from yak and herdsman. The Sul2 (>50%) gene of sulfonamide-resistant isolates from yak was predominant, and sul2> sul1> sul3. The sul3 gene was no identified in isolates of E. coli from yak. In 50 isolates, more than one gene coding for sulfonamide resistance was present:sul1 and sul2 in three.The Sul1 (>40%) gene of sulfonamide-resistant isolates from herdsman was predominant, and sul1> sul2> sul3. The sul3 gene was also identified in 3 isolates of E. coli from herdsman. In 40 isolates, more than one gene coding for sulfonamide resistance was present:sul1 and sul2 in five; sul1 and sul3 in one. Sulfonamide-resistant genes of herdsman were more complicated than yak's.
16 stains were detected by the simple PCR method of flor gene. Results showed that 14 (87.5%) flor genes was detected in 16 florfeniol-resistant isolates from yak,3(100%) flor gene was detected in 3 florfeniol-resistant isolates from herdsman.
4. The study on genetic relation of E. coli of yak and herdsman with the same resistance gene by PFGE
To investigate the dissemination of resistance between yak and herdsman in the same Serta County ranch.26 resistant E.coli isolated from two ranch and different host were divided into two groups, and each group had 13 stains with the same similar resistance gene(Sull or flor) profiles were characterized by pulsed-field gel electrophoresis (PFGE) after XbaI digestion by using the CHEF system of Bio-Lab. Software Qantity One was used to analyze genetic relationship study between stains. The results showed that 13 E.coli strains with sul1 gene were classified into 12 different subtypes in the first group. An E.coli clone was detected, and similarity index was up to 0.9 between C2 and C4 from herdsman. In the second group,13 E.coli strains with flor gene were classified into 8 different subtypes. Three E.coli clones were detected, and similarity index was up to 0.88 and 0.93 between B3 and B12、B13 from yak,respectively. The PFGE patterns of strains suggested that transmission of resistant E. coli clones between herdsman and herdsman, as well as yak and herdsman.The resistance relationship between yak and herdsman in Serta County ranch was analyzed for the first time. And the results of transmission of resistant E.coli clones between yak and herdsman were important evidence on managing antibiotics of animal strictly, and preventing resistance widespread.
5. Transformation test and conjugation test of E.coli of yak and herdsman with the same sulfonamide-resistance genes or florfeniol-resistance
The 19 resistant strains were divided into two groups. A group:the 7 strains from yak with flor gene were susceptive to Sulfamethoxazole. B group:the 12 strains from herdsman with Sull or Sul2 gene were susceptive to Florfeniol. Plasmid DNA was purified by Plasmid MiniPrep Kit of TianGen Company. The plasmid profile was analyzed by agarose gel electrophoresis. Gel electrophoresis analysis demonstrated the presence of many visible plasmid bands from every isolate. Plasmids were discovered in all E.coli strains. Each profile contained more than one kind of plasmid. E.coli strains contained maximum plasmid was 10, and minimum plasmid was 2. The molecular weight of plasmids was from 0.4×103 to 90.0×103bp.
19 kind plasmids were transformed into E.coli JM109 as recipient by Ca2 transformation. Then transformants was selected, plasmid DNA was extracted, MIC was measured and resistant genes were amplified by PCR. Results showed that the 7 kinds of plasmids with florfeniol-resistance gene from yak were transformed into E.coli JM109 separately.3 kinds of them were transformed successfully. While, The 12 kinds of plasmids with sulfonamide-resistance gene from herdsman were transformed into E.coli JM109 separately.6 kinds of them were transformed successfully. Transformation rate was 52.6% generally。The strains which could be transformed as donor were conjugated into E.coli C00 as recipient. Generated time of transconjugants was measured. Results showed that 2 strains in 4 with florfeniol-resistance from yak were conjugated into E.coli C00 successfully. And plasmid with flor gene was extracted from donor strain A12 and A172.5 strains in 6 with sulfanilamide-resistance from herdsman were conjugated into E.coli C00 successfully. And plasmid with sul1 gene was extracted from donor strain B1、B7 and H1,while sul2 gene from donor strain D 3and H5. The time of conjugation was from 3 to 6 hour. Transconjugants rate was 70% generally。On the one hand, the study revealed transmission of resistance by plasmid transformation and plasmid conjugal transfer, the transmission ratio and speed, which was important to provide the information on controlling transmission of resistance. On the other hand, plasmids with flor gene were identified from donor strain A12 and A172, and plasmids with sul1 or sul2 gene were identified from donor strain B1, B7, H1, D3 and H5,which would help to study on transmission of resistance between wildtype E.coli. The study on transmission of resistance plasmid systematically had not been reported in china Base on the special Tibetan pastureland, pathogenicity, serotype and MIC of E.coli isolates were indentified, which were beneficial to supply evidence to cure E.coli disease and guide the local civil and industrial needs. In the study, the resistance gene was checked from phenotypic resistance strains; genetic relationship was analyzed between yak and herdsman; and the character of transmission of resistance by plasmid was checked. The results were useful to manage antibiotics for animals strictly,
E. coli of yak and herdsman collected from Sertar County in Tibetan closure pastoral area in this study. Transmission of resistant E.coli clones between yak and herdsman was proved by PFGE. The character of transfer of resistance to medicinal was studied by plasmid conjugation. The results were useful to manage antibiotics for animals strictly and protect human health and sanitation.
本论文针对藏区牦牛、牧民源大肠杆菌进行分离鉴定、耐药性的传播,对磺胺药、氟苯尼考耐药基因等问题,开展了系列研究工作,取得以下结果：
1、藏区牦牛、牧民源大肠杆菌分离、血清学鉴定及16S rRNA分析
从四川甘孜色达藏区9个不同乡镇的牧场,采集了具有牦牛210份粪便样品及同牧场的90份鼻腔拭子,进行采集、接种、保存条件摸索,对分离大肠杆菌进行生化学、血清学和致病性鉴定,抽取40株分离菌株作16sRNA分析。结果表明,采用80%甘油加30%脱脂牦牛奶作保护剂,可将接种成功率从10%提高到70%,菌种能保存到一周以上。共分离出株114牦牛源大肠杆菌和70株牧民源大肠杆菌。有98株牦牛源大肠杆菌菌的血清型被鉴定出来,分属24种血清型,其中有9种优势血清型占了60%的比例。有58株牧民源大肠杆菌的血清型被鉴定出来,分属12种血清型,其中有6种优势血清型占了62.8%的比例。鉴定出了22株牦牛源为致病性大肠杆菌,有20株的血清型鉴定出来,其中O78、O26、O111所占的比例最高,分别为18.2%、13.6%、13.6%,为致病性大肠杆菌的优势血清型。16S rRNA分析,这些细菌都与登录的大肠杆菌同源性为98-99%。进化树结果表明,四川甘孜色达藏区牧民源的与牧民源大肠杆菌聚为一类,牦牛源与牦牛源大肠杆菌也聚为一类。
该研究首次建立了一套在高海拔、高寒条件下采样、分离、保存细菌的简单实用方法,该方法的建立为在当地开展细菌的科研工作铺下了的技术基石。鉴定了四川甘孜色达藏区牦牛致病性大肠杆菌的优势血清型。首次用16S rRNA鉴定了四川甘孜色达藏区牦牛、牧民的大肠杆菌,研究结果为进一步研究藏区牦牛源大肠杆菌提供了基础材料。
2、四川甘孜色达藏区牦牛、牧民源大肠杆菌对15种常用抗生素的MIC测定及比较
采用药物平板稀释法对四川甘孜色达藏区114株牦牛源和70株牧民源大肠杆菌进行15种抗菌药的MIC值测定,然后对结果进行的比较分析。结果表明,四川甘孜色达藏区牦牛源大肠杆菌对磺胺甲基异嗯唑、磺胺嘧啶、氟苯尼考的耐药性最高,分别为44%、40.4%、11.4%；对其他抗生素的耐药性低：分别为阿莫西林8.78%、氨苄西林6.14%、庆大霉素3.5%、链霉素1.75%；对新霉素、多西环素、土霉素、诺氟沙星、环丙沙星、萘啶酸、壮观霉素、头孢噻呋都敏感。四川甘孜色达藏区牧民源大肠杆菌对磺胺嘧啶和SMZ的耐药性最高,分别为57.1%和51.4%。而对其他抗生素的耐药性相对较低,从高到低分别氨苄西林22.9%、阿莫西林25.7%、链霉素20%、壮观霉素14.3%、庆大霉素11.4%、土霉素11.4%、头孢噻夫11.4%、萘啶酸11.4%、诺氟沙星8.57%、多西环素5.71%、氟苯尼考4.3%、环丙沙星2.86%、新霉素0%。比较牦牛源与牧民源大肠杆菌的耐药性发现：a、牧民源大肠杆菌的耐药性比牦牛源的比例高,种类多。b、两种来源的大肠杆菌都对磺胺药的耐药性在所有抗菌药中最高。c、在牧民不使用氟苯尼考的情况下,却检测出3株牧民源大肠杆菌对该药产生抗性。本研究首次对四川甘孜色达藏区的牧民、牦牛进行耐药性平行检测和比较分析数据,未见在同一环境中采样,对比分析牦牛与牧民源大肠杆菌耐药性的研究报道。该研究为治疗当地的大肠杆菌病提供了科学指导,为耐药性研究提供了更全面的资料。3、四川甘孜色达藏区牦牛、牧民源大肠杆菌对磺胺类和氟苯尼考耐药基因的PCR检测
为检测四川甘孜色达藏区大肠杆菌主要耐药表型的耐药基因,在单重PCR方法的基础上,建立了检测磺胺耐药基因Sul1.Sul2和Sul3的三重PCR方法。利用此方法分别对50株牦牛源大肠杆菌的耐磺胺药物的基因进行检测,结果发现,在耐磺胺的50株菌中,基因阳性率为94%。其中携带基因型Sul1,Sul2,Sul1+Sul2的比例分别为36%,52%,6%。对40株牧民源大肠杆菌中,基因阳性率为92.5%。其中携带基因型Sul1,Sul2,Sul3,Sul1+Sul2,Sul1+Sul3的比例分别为42.5%,27.5%,7.5%,12.5%,2.5%。比较牦牛源与牧民源的磺胺耐药基因发现,牧民源大肠杆菌的磺胺药耐药基因型比牦牛的多两种,基因种类多Su13。本研究在国内首次对牧区人和动物磺胺耐药基因分布比较进行比较,为研究人与动物的耐药基因库提供资料。4、用脉冲场凝胶电泳PFGE对牦牛、牧民相同耐药基因型的菌株的分析研究
为了研究同一个牧场里,牦牛和牧民之间是否存在耐药菌株的相互传播。本实验挑选26株耐药大肠杆菌,分为两组,每组13株菌,携带相同的耐药基因(Sull或flor),分离于两个牧场,来源不同宿主。采用脉冲场凝胶电泳(PFGE)进行分子分型和QantityOne软件进行菌株聚类分析。
结果发现,在第一组携带磺胺耐药基因sull的13株大肠杆菌可分成12个PFGE谱型,其中含有一个克隆系,菌株牧民源C2与C4之间的相似系数达到0.9。在第二组,携带有氟苯尼考耐药基因(flor)13株菌可分成8个PFGE谱型,含有三个克隆系。其中一个克隆系里牧民源菌株B3与牦牛源菌株B12、B13具有0.88和0.93的相似系数。这些数据表明了在同一个牧场内,牧民与牧民、牦牛与牧民、牦牛与牦牛之间都存在着相同PFGE分子型的相同耐药谱菌株,提供了耐药菌株水平传播的线索。与国内外的其它类似的研究比较,本实验在所选的对象上具有独特性,首次采用PFGE研究在藏区特殊生产和生活模式下的人和牛的耐药性关系,为保障牦牛产品安全和人类健康提供科学依据。5、携带磺胺耐药基因和氟苯尼考耐药基因大肠杆菌的转化试验和接合性试验
挑选有特别耐药性的19株菌进行分组。A组：牦牛源大肠杆菌株7株,携带有flor基因,对磺胺甲基异嗯唑敏感。B组：牧民源大肠杆菌12株,携带有Sull或Sul2基因,对氟苯尼考敏感。对所有细菌进行质粒提取,电泳分析质粒图谱；采用Ca2+转化法把各菌株的质粒转化到受体菌E.coli JM109中,然后挑选转化子,测MIC值,提取质粒,用PCR检测耐药基因；将所有菌与受体菌E.coli C00进行接合试验,并测定了产生接合子的时间。结果表明,每株菌都检测到多条大小不等的质粒DNA条带,质粒获得率为100%,质粒分子量为0.4×103～90.0×103bp。在A组7类质粒中,有4类质粒转化成功；在B组12类质粒中有6类质粒成功转化；总的转化率为52.6%。在接合试验中,发现质粒转化不成功的菌株都没有与受体菌接合成功,在含耐氟苯尼考耐药基因质粒的4株牦牛源大肠杆菌中有2株接合成功；在含耐磺胺药基因质粒的6株牧民源大肠杆菌中有5株接合成功：发生接合转移的时间为3h～6h；总的接合率为36.8%。
本实验在实验室证明了耐药性能通过质粒的转化和细菌的接合传播,揭示了耐药性通过质粒传播的比例与速度,为控制耐药性的传播提供了科学资料。同时,鉴定到了2株含有携带flor基因质粒的牦牛源供体菌A12、A17,携带Sul1、Sul2基因质粒的5株牦牛源供体菌B1、B7、H1、D3, H5,为进一步开展天然大肠杆菌耐药质粒传递的研究提供了素材。
本研究在四川甘孜色达四川甘孜色达藏区对分离自牦牛、牧民的大肠杆菌进行了致病性鉴定、血清学鉴定、MIC值检测,检测了主要耐药品种的耐药基因,用PFGE分析了同牧场中牦牛与牧民之间耐药菌株的关系,检测了耐药质粒对耐药性的传递特性,为指导当地藏民科学用药,有效防治大肠杆菌等细菌性疾病,保障牦牛产品安全,防制耐药性泛滥,保护人类健康提供了科学依据。
Because of adverse weather condition, distant far-flung and poor condition in Serta County with high altitude and extremely cold climate, there is no study on E. coli of Yak and herdsman in Serta County.Yaks are the most important to production material and living material for Tibetans. Yak E. coli disease is widespread in the pastoral area. As antibacterial is used widely, the problem of drug-resistance increased seriously. Because of the transmission of resistance, it was difficult to cure E. coli disease clinically. In order to get current state of resistance for yak and herdsman in Serta County Tibetans, and the mechanism of resistance transmission, the works had been launched as follows:
1. E.coli isolated and serotype identification and 16S rRNA analysis
210 samples of yaks faces and 90 human nasal swab were collected from 9 pastures in Serta County Plateau. The conditions were selected for inoculum and conservation of stains. The isolates were identified by biologic character,serotype and pathogenicity, which of 40 stains were identified by 16sRNA. The results showed that survival rate could be raised from 10% to 80% by taking 80% Glycerin and 10% skimmed milk as protective agent.114 E.coli stains of yak and 70 E.coli stains of herdsman were isolated.
The O serotype was identified by 165 kind's single factor E.coli O antisera. Results showed that 98 stains were identified of yak in 114. The E.coli strains of yak fell into 24 serotype groups of which the O101 (12.3%)、O2 (9.6%)、O68 (7.0%). O132 (7.0%)、O78 (5.3%)、O171 (5.3%)、O22 (4.4%)、O142 (4.4%)、O165 (4.4%) were predominant, accounted for 60%.58 stains were identified of herdsman in 70. E.coli strains of herdsman fell into 12 serotype groups of which the O81 (14.3%)、 030 (11.4%).05(11.4%)、0165(8.6%)、0132(8.6%)、O101(8.6%)were predominant, accounted for 62.8%. Serotype of yak was more than herdsman. And there was 7 same serotype between yak and herdsman, including 0132、O101、O15、08、078、0171、017, accounted for 37.5%(13/70). The pathogenicity of stains was checked by challenge assays for mice. Results showed that 22 strains were pathogenic to mice identified.20 strains isolated were identified by O serotype, but 2 strains were not. O78、O26、O111 were accounted for 18.2%、13.6%、13.6%, respectively. The serotype of 078、O26、0111 were predominant of pathogenic E.coli, accounted for 50%. The serotype of pathogenic E.coli of yak was identified firstly, which was important to produce vaccine for pathogenic yak E. coli.
40 stains from herdsman and yak were amplified for 16S rRNA and sequenced. All sequences of 40 stains were blasted in GenBank. Results showed that homology of the isolates were 98-99% with other E.coli. And phylogenetic tree was constructed. Results showed that stains between herdsmen clustered in the same group and that stains between yaks clustered in the same group, too. The results showed the genetic relationship of E.coli from Tibetan Area and others.
2. MIC testing and comparation of E.coli of yak and herdsman to 15 antibiotic in common use.
The MIC of 114 strains of yak and 70 strains of herdsman from 9 pastoral areas were examined for their susceptibility to 15 antimicrobial agents by drugs dilution-plate method. The results of antimicrobial susceptibility test were analyzed according to the standard procedure advised by NCCLS. The results showed that sufisomezole, sulfadiazine and florfeniol may be the most resistant antimicrobial agents tested in this study of yak, accounted for 44%、40.4%、11.4%, respectively. The resistant rate of stains from yak was low to other antibiotics. The resistant rate from high to low was amoxicillin (8.78%)、ampicillin(6.14%)、gentamicin(3.5%)、streptomycin(1.75%).All stains from yak were 100% sensitive to neomycin, doxycycline, terramycin, norfloxacin, ciprofloxacin, nalidixic acid, spectinomycin, ceftiofur sodium. The resistant rate of stains from herdsman was 57.1% and 51.4% to sulfadiazine and SMZ, respectively. The followed antimicrobial agents were ampicillin(22.9%), amoxicillin(25.7%), streptomycin(20%), spectinomycin(14.3%), terramycin(11.4%), ceftiofur sodium(11.4%), norfloxacin(8.57%), doxycycline(5.71%), florfeniol(4.3%), ciprofloxacin(2.86%), Neomycin(0%). In summary, by comparing resistance of yak with herdsman, we can draw the conclusions:1. the resistance of herdsman was more serious than yak's in this study; 2. the sulfonamide-resistance was highest in all the antimicrobial agents; 3. the florfeniol-resistance was detected in 3 strains of herdsman, while florfeniol was prohibited in human to treatment of the diseases.
The results of drug sensitivity test of E.coli from Serta County were help to cure E. coli disease. At the same time, the results were useful to parallel examination and data analysis for yak and herdsman, understand the problem of resistance overall.
3. Detection of PCR for sulfonamide-resistance genes and florfeniol-resistance gene of E.coli of yak and herdsman
In order to detected resistance gene of E.coli in Sertar County in Tibetan pastoral area, the multi-PCR for Sul1, Sul2 and Sul3 gene and simple PCR for flor gene were established. By the multi-PCR method,50 strains of yak and 40 strains of herdsman sulfonamide-resistant isolates were checked. Results showed that sulfonamide-resistance was different from yak and herdsman. The Sul2 (>50%) gene of sulfonamide-resistant isolates from yak was predominant, and sul2> sul1> sul3. The sul3 gene was no identified in isolates of E. coli from yak. In 50 isolates, more than one gene coding for sulfonamide resistance was present:sul1 and sul2 in three.The Sul1 (>40%) gene of sulfonamide-resistant isolates from herdsman was predominant, and sul1> sul2> sul3. The sul3 gene was also identified in 3 isolates of E. coli from herdsman. In 40 isolates, more than one gene coding for sulfonamide resistance was present:sul1 and sul2 in five; sul1 and sul3 in one. Sulfonamide-resistant genes of herdsman were more complicated than yak's.
16 stains were detected by the simple PCR method of flor gene. Results showed that 14 (87.5%) flor genes was detected in 16 florfeniol-resistant isolates from yak,3(100%) flor gene was detected in 3 florfeniol-resistant isolates from herdsman.
4. The study on genetic relation of E. coli of yak and herdsman with the same resistance gene by PFGE
To investigate the dissemination of resistance between yak and herdsman in the same Serta County ranch.26 resistant E.coli isolated from two ranch and different host were divided into two groups, and each group had 13 stains with the same similar resistance gene(Sull or flor) profiles were characterized by pulsed-field gel electrophoresis (PFGE) after XbaI digestion by using the CHEF system of Bio-Lab. Software Qantity One was used to analyze genetic relationship study between stains. The results showed that 13 E.coli strains with sul1 gene were classified into 12 different subtypes in the first group. An E.coli clone was detected, and similarity index was up to 0.9 between C2 and C4 from herdsman. In the second group,13 E.coli strains with flor gene were classified into 8 different subtypes. Three E.coli clones were detected, and similarity index was up to 0.88 and 0.93 between B3 and B12、B13 from yak,respectively. The PFGE patterns of strains suggested that transmission of resistant E. coli clones between herdsman and herdsman, as well as yak and herdsman.The resistance relationship between yak and herdsman in Serta County ranch was analyzed for the first time. And the results of transmission of resistant E.coli clones between yak and herdsman were important evidence on managing antibiotics of animal strictly, and preventing resistance widespread.
5. Transformation test and conjugation test of E.coli of yak and herdsman with the same sulfonamide-resistance genes or florfeniol-resistance
The 19 resistant strains were divided into two groups. A group:the 7 strains from yak with flor gene were susceptive to Sulfamethoxazole. B group:the 12 strains from herdsman with Sull or Sul2 gene were susceptive to Florfeniol. Plasmid DNA was purified by Plasmid MiniPrep Kit of TianGen Company. The plasmid profile was analyzed by agarose gel electrophoresis. Gel electrophoresis analysis demonstrated the presence of many visible plasmid bands from every isolate. Plasmids were discovered in all E.coli strains. Each profile contained more than one kind of plasmid. E.coli strains contained maximum plasmid was 10, and minimum plasmid was 2. The molecular weight of plasmids was from 0.4×103 to 90.0×103bp.
19 kind plasmids were transformed into E.coli JM109 as recipient by Ca2 transformation. Then transformants was selected, plasmid DNA was extracted, MIC was measured and resistant genes were amplified by PCR. Results showed that the 7 kinds of plasmids with florfeniol-resistance gene from yak were transformed into E.coli JM109 separately.3 kinds of them were transformed successfully. While, The 12 kinds of plasmids with sulfonamide-resistance gene from herdsman were transformed into E.coli JM109 separately.6 kinds of them were transformed successfully. Transformation rate was 52.6% generally。The strains which could be transformed as donor were conjugated into E.coli C00 as recipient. Generated time of transconjugants was measured. Results showed that 2 strains in 4 with florfeniol-resistance from yak were conjugated into E.coli C00 successfully. And plasmid with flor gene was extracted from donor strain A12 and A172.5 strains in 6 with sulfanilamide-resistance from herdsman were conjugated into E.coli C00 successfully. And plasmid with sul1 gene was extracted from donor strain B1、B7 and H1,while sul2 gene from donor strain D 3and H5. The time of conjugation was from 3 to 6 hour. Transconjugants rate was 70% generally。On the one hand, the study revealed transmission of resistance by plasmid transformation and plasmid conjugal transfer, the transmission ratio and speed, which was important to provide the information on controlling transmission of resistance. On the other hand, plasmids with flor gene were identified from donor strain A12 and A172, and plasmids with sul1 or sul2 gene were identified from donor strain B1, B7, H1, D3 and H5,which would help to study on transmission of resistance between wildtype E.coli. The study on transmission of resistance plasmid systematically had not been reported in china Base on the special Tibetan pastureland, pathogenicity, serotype and MIC of E.coli isolates were indentified, which were beneficial to supply evidence to cure E.coli disease and guide the local civil and industrial needs. In the study, the resistance gene was checked from phenotypic resistance strains; genetic relationship was analyzed between yak and herdsman; and the character of transmission of resistance by plasmid was checked. The results were useful to manage antibiotics for animals strictly,
E. coli of yak and herdsman collected from Sertar County in Tibetan closure pastoral area in this study. Transmission of resistant E.coli clones between yak and herdsman was proved by PFGE. The character of transfer of resistance to medicinal was studied by plasmid conjugation. The results were useful to manage antibiotics for animals strictly and protect human health and sanitation.
引文
1. K. A. Bettelheim, Alwena Breadon, Mary C. Faiers et.c, The origin O serotpes of Escherichia coil in babies after normal delivery, Journal of Hygiene(1974),72:67-70
2. Sherwood D,Snodgrass DR,O'Brien AD.Shiga-like toxin production from Escherichia coli associated with calf diarrhoea[J].Vet Rec.1985,116(8):217-218.
3. 陆承平.兽医微生物学.北京：中国农业出版社,2006：215-223.
4. Kappeli U, Hachler H, Giezendanner N, et al. Human infections with non-0157 Shiga toxin-producing Escherichia coli, Switzerland,2000-2009. Emerg Infect Dis.2011,17(2):180-5.
5. Unno T, Han D, Jang J, et al.High diversity and abundance of antibiotic-resistant Escherichia coli isolated from humans and farm animal hosts in Jeonnam Province, South Korea. Sci Total Environ.2010,408(17):3499-506.
6. Ozawa M, Baba K, Asai T.Molecular typing of avian pathogenic Escherichia coli O78 strains in Japan by using multilocus sequence typing and pulsed-field gel electrophoresis. J Vet Med Sci.2010,72(11):1517-20.
7. Wang XM, Liao XP, Liu SG, et al.Serotypes, Virulence Genes, and Antimicrobial Susceptibility of Escherichia coli Isolates from Pigs. Foodborne Pathog Dis. 2011,2. [Epub ahead of print]
8. Checkley SL, Campbell JR, Waldner CL, et al.A retrospective diagnostic laboratory survey of antimicrobial resistance in fecal Escherichia coli isolated from spring calves in western Canada. Can Vet J.2010,51(11):1283-6
9. Ozaki H, Esaki H, Takemoto K,et al.Antimicrobial resistance in fecal Escherichia coli isolated from growing chickens on commercial broiler farms. Vet Microbiol. 2010,23. [Epub ahead of print]
10. Medina A, Horcajo P, Jurado S, et al.Phenotypic and genotypic characterization of antimicrobial resistance in enterohemorrhagic Escherichia coli and atypical enteropathogenic E. coli strains from ruminants. J Vet Diagn Invest. 2011,23(1):91-5.
11. Harada K, Morimoto E, Kataoka Y, et al.Clonal spread of antimicrobial-resistant Escherichia coli isolates among pups in two kennels. Acta Vet Scand. 2011,17;53:11.
12.万根平,黄勇,邓秋连,等,儿童肠道感染致病性大肠埃希菌血清型分布及耐药性研究,实用医学杂志,2010,26(2),310-311
13.谢永强,邓秋连,万根平,等.广州地区儿童感染性腹泻的病原学研究.中国当代儿科杂志,2009,11(2)：107-109.
14.赵兰兰,朱朝敏,张爱华.1997—2006年重庆地区儿童细菌性腹泻病原菌分布与药敏结果分析.中国实用儿科杂志,2008,23(1)：45-49.
15.喻华英,贾桂珍,邹开胜。犊牛腹泻病中大肠杆菌的分离与鉴定,黑龙江畜牧兽医,2006(6),67-68
16. Thorsteinsdottir TR, Haraldsson G, Fridriksdottir V, et al.Prevalence and genetic relatedness of antimicrobial-resistant Escherichia coli isolated from animals, foods and humans in Iceland. Zoonoses Public Health.2010,57(3):189-96.
17.陈明勇,陈德威,曾群辉,等,牦牛肠毒素型大肠杆菌的分离鉴定和某些生物学特性的研究,中国预防兽医学报,2001,24(4)：277-279.
18.陈明勇,张冰 陈德威,等,牦牛致病性大肠杆菌生物学特性研究,中国农业大学学报2001,6(3)：119-122
19. Kaper J B, Nataro J P, Mobley H L. Pathogenic Escherichia coli[J].Nat Rev Microbio,2004,2(2):123-14
20. Garcia PG, Silva VL, Diniz CG. Occurrence and antimicrobial drug susceptibility patterns of commensal and diarrheagenic Escherichia coli in fecal microbiota from children with and without acute diarrhea. J. Microbiol.2011,49(1):46-52.
21. Sack RB.The discovery of cholera-like enterotoxins produced by Escherichia coli causing secretory diarrhoea in humans. Indian J Med Res.2011, 133(2):171-80.
22. Evans DJ, Evans DG.Escherichia Coli in Diarrheal Disease. In:Baron S, editor. Medical Microbiology.4th edition. Galveston (TX):University of Texas Medical Branch at Galveston; 1996. Chapter 25.
23.周凯,郑海洲,边艳青,等,肠产毒性大肠杆菌分子生物学及基因工程疫苗的研究进展,徽生物学杂志,2003,23(5)：44-47
24.王建阳,致病性大肠杆菌和出血性大肠杆菌的研究进展,中国热带医学,2004,4(2)：292-294
25. Yin X, Zhu J, Feng Y, et al.Differential Gene Expression and Adherence of Escherichia coli O157:H7 In Vitro and in Ligated Pig Intestines. PLoS One.2011, 28;6(2):e17424.
26.裴迎新,王晓平,闫滨,等,分子分型方法在肠出血性大肠杆菌检测中的应用,中国公共卫生管理,2009,25(4),415-417
27.张志果,罗寒,杨好施,等.一起由侵袭性大肠杆菌引起的食物中毒.中华流行病学杂志,1987,8(4)：250.
28. Xu JG, Cheng B, Wen X, et al.High-pathogenicity island of Yersinia spp. in Escherichia coli strains isolated from diarrhea patients in China. J Clin Microbiol. 2000,38(12):4672-5.
29.沈宪文,仔猪大肠杆菌耐药性分析及耐磺胺类药物基因的检测[学位论文],长春,吉林大学,2003。
30. IIalnmerum AM, Detection of sull, sul2 and sul3 in sulphonamide resistant Eseheriehia coli isolates obtained from healthy humans, pork and pigs in Demark. Int J Food Microbiol.,2006,106(2):235-237
31.羊云飞,王红宁,谭雪梅,等,二重PCR检测猪、鸡源致病性大肠杆菌、沙门氏菌磺胺类耐药基因(Sull、Sul2、Sul3)的研究,畜牧兽医学报2007,38(10)：1088-1092
32.周万蓉,王红宁,张安云,等,猪和野生动物源大肠杆菌及沙门菌中磺胺类药物耐药基因的检测,中国兽医科学2007,37(04)：287-29
33. Wu S, Dalsgaard A, Hammerum AM, et al.Prevalence and characterization of plasmids carrying sulfonamide resistance genes among Escherichia coli from pigs, pig carcasses and human. Acta Vet Scand.2010,30;52:47
34.康立超,黄新,何延华,等,犊牛耐药性大肠杆菌的分离鉴定,新疆农垦科技,2010,2：53-54
35. Aslam M, Stanford K, McAllister TA.Characterization of antimicrobial resistance and seasonal prevalence of Escherichia coli O157:H7 recovered from commercial feedlots in Alberta, Canada. Lett Appl Microbiol.2010,50(3):320-6.
36. Swedberg, G, C. Fermer, and O. Skold.1993. Point mutations in the dihydropteroate synthase gene causing sulfonamide resistance. Adv. Exp. Med. Biol.338:555-558.
37. Vedantam, G., G. G. Guay, N. E. Austria, S. Z. Doktor, and B. P. Nichols. Characterization of mutations contributing to sulfathiazole resistance in Escherichia coli. Antimicrob. Agents Chemother.1998.42:88-93.
38. Skold O. Sulfonamide resistance:mechanisms and trends. Drug Resist Update, 20003:155-60.
39. Skold O. R-factor-mediated resistance to sulfonamides by a plasmid-borne, drug-resistant dihydropteroate synthase. Antimicrob Agents Chemother 1976; 9: 49-54.
40. Radstrom, P., and G Swedberg. RSF1010 and a conjugative plasmid contain sulll, one of two known genes for plasmid-borne sulfonamide resistance dihydropteroate synthase. Antimicrob. Agents Chemother.1988.32:1684-1692.
41. Sundstrom, L., P. Radstrom, G. Swedberg, and O. Skold. Site-specific recombination promotes linkage between trimethoprim- and sulfonamide resistance genes. Sequence characterization of dhfrV and sull and a recombination active locus of Tn21.1988.Mol. Gen. Genet.213:191-201.
42. Swedberg, G., and O. Skold. Characterization of different plasmid-borne dihydropteroate synthases mediating bacterial resistance to sulfonamides. J. Bacteriol.1980.142:1-7.
43. Enne VI, King A, Livermore DM, Hall LM. Sufonamide resistance in Haemophilus influenzae mediated by acquisition of sul2 or a short insertion in chromosomal folP. Antimicrob Agents Chemother 2002;46:1934-9.
44. Perreten V, Boerlin P. A new sulfonamide resistance gene (sul3) in Escherichia coli is widespread in the pig population of Switzerland. Antimicrob Agents Chemother 2003;47:1169-72.
45. Swedberg G, Skold O. Plasmid-borne sulfonamide resistance determinants studied by restriction enzyme analysis. J Bacteriol 1983; 153:1228-1237.
46. Radstrom, P., G. Swedberg, and O. Skold. Genetic analyses of sulfonamide resistance and its dissemination in gram-negative bacteria illustrate new aspects of R plasmid evolution. Antimicrob. Agents Chemother.1991.35:1840-1848.
47. Van Treeck UF, Schmidt F,Wiedemann B. Molecular nature of a streptomycin and sulfonamide resistance plasmid (pBPI) prevalent in clinical Escherichia coli strains and integration of an ampicillin resistance transposon (TnA).Antimicrob Agents Chemother 1981;19:371-380.
48. Scholz P, Haring V, Wittmannliebold B, Ashman K, Bagdasarian M, Scherzinger E. Complete nucleotide-sequence and gene organization of the broadhost-range plasmid RSF1010. Gene1989;75:271-88.
49. Liu, J., Keelan, P., Bennett, P. M., Enne, V. I. Characterization of a novel macrolide efflux gene, mef(B), found linked to sul3 in porcine Escherichia coli.J Antimicrob Chemother 2009,63:423-426
50. Boerlin, P., R. Travis, C. L. Gyles, R. et al. Friendship, and M. Archambault. Antimicrobial resistance and virulence genes of Escherichia coli isolates from swine in Ontario. Appl. Environ. Microbiol.2005.71:6753-6761.
51. Kerrn MB, Klemmensen T, Frimodt-Mφller N, Espersen F.Susceptibility of Danish Escherichia coli strains isolated from urinary tract infections and bacteraemia, and distribution of sul genes conferring sulphonamide resistance. J Antimicrob Chemother 2002;50:513-6.
52. Kozak GK, Pearl DL, Parkman J, Reid-Smith RJ, Deckert A, Boerlin P. Antimicrobial Resistance in Escherichia coli Isolates from Swine and Wild Small Mammals in the Proximity of Swine Farms and in Natural Environments in Ontario, Canada.Appl Environ Microbiol.2009,75(18):5999-6001.
53. Guerra, B., E. Junker, and R. Helmuth. Incidence of the recently described sulfonamide resistance gene sul3 among German Salmonella enterica strains isolated from livestock and food. Antimicrob. Agents Chemother. 2004.48:2712-2715.
54. Koljalg S, Truusalu K, Vainumae I,et al.Persistence of Escherichia coli clones and phenotypic and genotypic antibiotic resistance in recurrent urinary tract infections in childhood. Clin Microbiol.2009,47(1):99-105.
55. Bean, D. C., D. M. Livermore, I. Papa, and L. M. C. Hall. Resistance among Escherichia coli to sulphonamides and other antimicrobials now little used in man. J. Antimicrob. Chemother.2005.56:962-964.
56. Bean, D. C., Livermore, D. M., Hall, L. M. C. Plasmids Imparting Sulfonamide Resistance in Escherichia coli:Implications for Persistence. Antimicrob. Agents Chemother.2009,53:1088-1093
57. Aminov R, Mackie RI. Evolution and ecology of antibiotic resistance genes. FEMS Microbiol Lett 2007; 271:147-61.
58.羊云飞,多重PCR检测沙门氏菌、大肠杆菌对磺胺类、氯霉素类药物耐药基因的研究[学位论文],雅安,四川农业大学,2004
59.张铁,王春光,王谦,猪源大肠杆菌的分离、鉴定及耐药性监测,中国农学通报,2005,12：34-36
60.杜向党,李新生,张素梅,等,鸡源大肠杆菌氟苯尼考耐药基因floR的分子检测,河南农业大学学报,2007,41(2)：20-23
61.郑朝朝,刘聚祥,李辉,等,鸡源、猪源大肠杆菌氟苯尼考耐药基因flor的克隆与序列分析,华北农学报,2010,25(5)：72-75.
62. Kim E, Aoki T. Sequence analysis of the florfenicol resistance gene encoded in the transferable R-plasmid of a fish pathogen. Microbiol Immuno,l 1996,40(9): 665-669.
63. Briggs CE, Fratamico PM. Molecular characterization of an antibiotic resistance gene cluster of Salm onella typhim urium DT104[J]. Antimicrob Agents Chemother,1999,43 (4):846-849
64. Bolton L, KelleyL, LeeM,etal.Detection ofmulti-drug resistant Salmonella entericaserotypeTyphimurium DT104 based on a gene which confers cross-resistance to florfenicol and chloramphenicol. JClinMicrobio,l 1999,37(5): 1348-1351.
65. Kehrenberg C, Meunier D, Targant H, et al.Plasmid-mediated florfenicol resistance in Pasteurella trehalosi.J Antimicrob Chemother.2006;58(1):13-7.
66. Kehrenberg C, Schwarz S.Plasmid-borne florfenicol resistance in Pasteurella multocida.J Antimicrob Chemother.2005;55(5):773-5.
67. Doublet, B., S. Schwarz, E. Nussbeck,et al. Molecular analysis of chromosomally florfenicol resistant Escherichia coli isolates from France and Germany. J. Antimicrob. Chemother.2002.49:49-54.
68. Blickwede, M., Schwarz, S. Molecular analysis of florfenicol-resistant Escherichia coli isolates from pigs. J Antimicrob Chemother 2004,53:58-64
69. Li XS, Wang GQ, Du XD, et al.Antimicrobial susceptibility and molecular detection of chloramphenicol and florfenicol resistance among Escherichia coli isolates from diseased chickens.J Vet Sci.2007,8(3):243-7.
70. Meunier D, Jouy E, Lazizzera C, et al. Plasmid-borne florfenicol and ceftiofur resistance encoded by the floR and blaCMY-2 genes in Escherichia coli isolates from diseased cattle in France.J Med Microbiol.2010,7. [Epub ahead of print]
71. White, D. G., C. Hudson, J. J. Maurer, et al. Sherwood. Characterization of chloramphenicol and florfenicol resistance in Escherichia coli associated with bovine diarrhea. J. Clin. Microbiol.2000.38:4593-4598.
72. Cloeckaert, A., S. Baucheron, and E. Chaslus-Dancla. Nonenzymatic chloramphenicol resistance mediated by IncC plasmid R55 is encoded by a floR gene variant. Antimicrob. Agents Chemother.2001.45:2381-2382.
73. Schwartz DC, Cantor CR-Separation ofyeast chromosome-sized DNAs by pulsed field gradient gel electrophoresis. Cel,l 1984,37:67-75.
74.王丽丽,徐建国,脉冲场凝胶电泳技术(PFGE)在分子分型中的应用现状,疾病监测,2006,21(5),276-279.
75.丁水军,脉冲场凝胶电泳技术及其在病原菌分子分型中的应用,中国卫生检验杂志,2009,19(4),962-964.
76. Beadle J,WrighMt,McNeelyL,et al-Electrophoretic karyotype analysis in fungi.Adv App Ml icrobio,l 2003,53:243-270.
77.边银丙,罗信昌,脉冲电泳技术及其在食用菌研究中的应用,食用菌学报,1996,3(2)：45-50
78. Lai E, Birren BW, Clark SM, et al. Pulsed field gel electrophoresis Biotechniques,1989,7(1):34-42
79. ZhangTY, Smith CL,CantorCR-Secondary pulsed field gel electrophoresis:a new method for faster separation of larger DNA molecules[J]·Nucleic Acids Research, 1991,19(6):1291-1296
80.时连根,PFGE技术及其在昆虫病原真菌研究中的应用,微生物学通报,2000,27(3)：212-215
81. Martinez-Urtaza Jaime,Lozano-Leon Antonio,DePaola Angelo,et al.Characterization of Pathogenic Vibrio parahaemolyticusIsolates from Clinical Sources in Spain and Comparison withAsian and North American Pandemic Isolates.J Clin Micro-biol,2004,42:4672-4678
82.康梅,申艳娜,脉冲场凝胶电泳在医院内感染大肠杆菌的分子流行病学的应用研究,华西医学,2002；17(1),34-35。
83.周晓明,卢林耿,卫国荣,等,脉冲场电泳进行E.coli 0157的分型,复旦学报(医学科学版),2001,28(1)：71
84.胡云建,杜迪君,张秀珍,产超广谱p-内酰胺酶大肠埃希菌的耐药性及脉冲场电泳分型研究,中华医学感染学杂志,2000,10(2)：154.
85. Katsunuma Y, Hanazumi M, Fujisaki H, Minato H, Kataoka Y, Sawada T, Hashimoto Y, Yonemochi C.Comparison of pulsed-field gel electrophoresis patterns of antimicrobial-resistant Escherichia coli and enterococci isolates from the feces of livestock and livestock farmers in Japan. J Gen Appl Microbiol. 2008,54(1):39-50.
86.杨玲丽,陈杖榴,刘健华,等,动物、环境及饲养员多重耐药大肠杆菌的PFGE分型研究,中国农业科学2005,39(12)：2597-2602。
87. Donabedian S M,Thal L A,Hershberger E,et al.Molecular characterization of gentamicin-resistant Enterococci in theUnited States:evidence of spread from animals to humans through food.Journal of Clinical Microbiology,2003,41:1109-1113.
88.黄彦,孙贵娟,唐振柱,等,出血性大肠杆菌0157：H7的脉冲场凝胶电泳分型方法研究,应用预防医学,2007,13(1),19-22.
89.李聪智,谭德明.聚合酶链反应检测细菌16S rRNA/16S rDNA,湖南医学学报,1999,16(2)：88-89.
90.金鑫,李妍,陈代杰,PCR扩增rRNA基因在细菌菌种鉴定中的应用,国外医药抗生素分册,2003,24(5)：223.
91.周爆,16S rRNA/16S rDNA序列分析法在医学微生物鉴定中的应用,生物技术通讯,1999,10(4)：297-305.
92.J.萨姆布鲁克,D.W.拉塞尔.著,黄培唐等译,分子克隆实验指南(第三版).科学出版社.2002.
93.R.E.布坎南,N.E吉本斯等伯杰细菌鉴定手册(第八版),450-452.
94. Drancourt.M, PBerger,D.Raoult.2004. Systematic 16S rRNA Gene Sequencing of Atypical Clinical Isolates Identified 27 New Bacterial Species Associated with Hunans. Jurnal of Clinical Microbiology.5:5:2197-2202
95.时全,黄新明,李朝阳,等,致泻大肠埃希菌感染在腹泻病中地位的研究,中国卫生检验杂志,2005,15(1)：5-8.
96. Alikhani M Y, Mirsalehian A, Aslani M M. Detection of typical and atypical enteropathogenic Escherichia coli (EPEC) in Iranian children with and without diarrhoea. J Med Microbiol,2006,55 (9):1159-1163.
97. Vignoli R, Varela G, Mota M I, et al. Enteropathogenic Escherichia coli strains carrying genes encoding the PER-2 and TEM-116 extended-spectrum beta-lactamases isolated from children with diarrhea in Uruguay. J Clin Microbiol,2005,43 (6):2940-2943.
98.杨锦红,任春阳,王军.肠致病性大肠埃希菌血清型分布及耐药性分析,实验与检验医学,2008,26(2)：143-144.
99.叶迎春,赵世鸿,凌体淑.三种菌种的保存比较,中国吴诊学杂志,2004,4(3)386-389.
100.方光远,张志成,晏文梅.几种不同条件下细菌菌株保存试验。金陵科技学院学报。2004,9,20(3)
101.张绪利,方晓红,贾瑛.用液体石蜡保存菌种的新方法.临床检验杂志.2005,(23)5,362-364.
102.黄霞云,菌种保存方法的改进.广州医学院学报.1999,(17)1,73-74
103.房海主编,大肠埃希氏菌,石家庄：河北科学技术出版社,1997
104.方光远,金兰梅,闻发全,等,078败血型犊牛大肠杆菌的分离和鉴定,金陵科技学院学报,2007,23(1)：105-107
105.方光远,张姝,张玉红,等。腹泻犊牛大肠杆菌的分离鉴定和药敏试验。中国兽医杂志,2008,44(10),33-34.
106.陈明勇,张冰,陈德成,等,西藏地区牦牛致病性大肠杆菌的分离鉴定,中国预防兽医学报,2001,23(5)：389-390.
107.徐明举,陈建新,李寸欣,等,引起犊牛腹泻的致病性大肠杆菌的分离鉴定,兽医科技,2009,11：88-89。
108.胡智斌,宋念华,李德学,等,,湖北省犊牛致病性大肠杆菌病的检测与分离鉴定,湖北农业科学,2006,45(3)：362-364
109.斯木吉德,敖日格乐,王纯洁,等,6种血清型牛源致病性大肠杆菌的体外抑菌效果研究,黑龙江畜牧兽医,2009,9：69-70
110.Graves AK, Liwimbi L, Israel DW, van Heugten E, Robinson B, Cahoon CW, Lubbers JF.Distribution of ten antibiotic resistance genes in E. coli isolates from swine manure, lagoon effluent and soil collected from a lagoon waste application field. Folia Microbiol (Praha).2011,29. [Epub ahead of print]
111.朱岩丽,康丽,杨其峰,等,泰安周边地区鸡致病性大肠杆菌的分离鉴定与药敏试验,山东畜牧兽医,2007,15(2)：67-68.
112.刘明春,于立辉,何剑斌,等。犊牛腹泻病原菌的分离鉴定及敏感药物筛选。黑龙江畜牧兽医,2005,(12)：42-43
113.Sarma JB, Bhattacharya PK, Kalita D, et al.Multidrug-resistant Enterobacteriaceae including metallo-β-lactamase producers are predominant pathogens of healthcare-associated infections in an Indian teaching hospital. Indian J Med Microbiol.2011,29(1):22-7.
114.王丽荣,胡婕,卢晓辉,等,豫北地区致病性鸡大肠杆菌的分离鉴定,中国 兽医杂志,2007,55(11)：38-39.
115.吴信明,连洪梅,王艳,等,38株鸭源大肠杆菌的分离鉴定与药敏试验,中国畜牧兽医,2010,37(10)：178-180
116.王红宁,刘书亮,陶勇,等,规模化猪场致病性大肠杆菌、沙门氏菌药敏区系调查,西南农业学报,2000,13：84-90.
117.Smith MG, Jordan D, Chapman TA, et al.Antimicrobial resistance and virulence gene profiles in multi-drug resistant enterotoxigenic Escherichia coli isolated from pigs with post-weaning diarrhoea. Vet Microbiol.2010,26; 145(3-4):299-307.
118.Jiang HX, Lii DH, Chen ZL, et al.High prevalence and widespread distribution of multi-resistant Escherichia coli isolates in pigs and poultry in China. Vet J.2011, 187(1):99-103.
119.Scaria J, Warnick LD, Kaneene JB, et al.Comparison of phenotypic and genotypic antimicrobial profiles in Escherichia coli and Salmonella enterica from the same dairy cattle farms. Mol Cell Probes.2010,24(6):325-45.
120.Vinson HM, Gautam A, Olet S, Gibbs PS, Barigye R.Molecular analysis of porin gene transcription in heterogenotypic multidrug-resistant Escherichia coli isolates from scouring calves. J Antimicrob Chemother.2010,65(9):1926-35.
121.Yue L, Jiang HX, Liao XP, et al.Prevalence of plasmid-mediated quinolone resistance qnr genes in poultry and swine clinical isolates of Escherichia coli. Vet
122.Delsol AA, Halfhide DE, Bagnall MC, et al.Persistence of a wild type Escherichia coli and its multiple antibiotic-resistant (MAR) derivatives in the abattoir and on chilled pig carcasses. Int J Food Microbiol.2010, 140(2-3):249-53.
123.Zhao J, Chen Z, Chen S, et al. Prevalence and dissemination of oqxAB in Escherichia coli isolates from animals, farmworkers, and the environment. Antimicrob Agents Chemother.2010,54(10):4219-24.
124.Zhang XY, Ding LJ, Yue J.Occurrence and characteristics of class 1 and class 2 integrons in resistant Escherichia coli isolates from animals and farm workers in northeastern China. Microb Drug Resist.2009,15(4):323-8.
125.Alali WQ, Scott HM, Harvey RB, et al.Longitudinal study of antimicrobial resistance among Escherichia coli isolates from integrated multisite cohorts of humans and swine. Appl Environ Microbiol.2008,74(12):3672-81.
126.Phongpaichit S, Liamthong S, Mathew AG, et al.Prevalence of class 1 integrons in commensal Escherichia coli from pigs and pig farmers in Thailand. J Food Prot. 2007,70(2):292-9.
127.Scott HM, Campbell LD, Harvey RB, et al.Patterns of antimicrobial resistance among commensal Escherichia coli isolated from integrated multi-site housing and worker cohorts of humans and swine. Foodborne Pathog Dis.2005, 2(1):24-37.
128.Gebreyes WA, Thakur S.Multidrug-resistant Salmonella enterica serovar Muenchen from pigs and humans and potential interserovar transfer of antimicrobial resistance. Antimicrob Agents Chemother.2005,49(2):503-11.
129.汪洋,易力,王红宁,等,川西北牦牛致病性大肠杆菌的分离鉴定及药敏试验,中国兽医杂志,2008,44(5)：36-37
130.叶应妩、王毓三,全国临床检验操作规程(第二版).东南大学出版社,1997,62-567
131.戴白英,刘裕昆,实用抗菌药物学(第二版),人民卫生出版社,1998,203-20
132. CLSI. Performance Standards for Antimicrobial Susceptibility Testing; Nineteenth Informational Supplement. Wayne, PA:Clinical and Laboraory Stadards Instiute; 2009.
133.邢艳苹,王瑜,杨峰,朱僧,等,动物源性大肠杆菌耐药性分析,吉林畜牧兽医,2010,31(11)：7-10
134.于桂阳,湖南省规模化猪场猪源大肠杆菌耐药性调查,猪病防控,2010,11：23-26
135.魏雅静,林居纯,毕师诚,等,四川省不同地区猪源大肠杆菌耐药性调查,安徽农业科学,2011,39(1)：273-274。
136.苟清碧,聂奎,鸭源致病性大肠杆菌的分离鉴定及耐药性分析,黑龙江畜牧 兽医,2010,10,：92-93
137.廖娟,王红宁,黄勇,等,牦牛致病性大肠杆菌的分离鉴定及药敏试验,畜牧与兽医,2006,8(8)：49-50
138.黑占珠,谢仲强,青海果洛州德昂乡屠宰牦牛源大肠杆菌耐药性观察,青海畜牧兽医杂志,2005,35(2)：3-4
139.崔保安,王学斌,李新生,犊牛腹泻病原分离鉴定及中药防治试验,中国兽医杂志,1998,24(10)：40-41
140.Gad GF, Mohamed HA, Ashour HM.Aminoglycoside resistance rates, phenotypes, and mechanisms of gram-negative bacteria from infected patients in Upper Egypt. PLoS One.2011 Feb 17; 6(2):e17224.
141.Japoni A, Vazin A, Hamedi M, et al..Multidrug-resistant bacteria isolated from intensive-care-unit patient samples. Brazilian Journal Infect Dis. 2009,3(2):118-22.
142.桓新,卢大雷等.健康人群与家鸡大肠杆菌的耐药性分析.实用预防医学.2007,14(10)1648-1649.
143.白迎春,李采青,张立永,等,临床分离人源大肠杆菌耐药性的测定,河北北方学院学报(医学版),2010,27(2)：12-15
144.Stenske KA, Bemis DA, Gillespie BE,et al.Comparison of clonal relatedness and antimicrobial susceptibility of fecal Escherichia coli from healthy dogs and their owners. Am J Vet Res.2009,70(9):1108-16
145.穆新林.超广谱β-内酰胺酶细菌下呼吸道感染的监测及危险因素分析,中华医院感染学杂志,2002,12(2)：94-96
146.Trobos M, Jakobsen L, Olsen KE,et al. Prevalence of sulphonamide resistance and class 1 integron genes in Escherichia coli isolates obtained from broilers, broiler meat, healthy humans and urinary nfections in Denmark. Int J Antimicrob Agents 2008,32:367-369.
147.Radstrom P, Swedberg G, Skold O:Genetic analyses of sulfonamide resistance and its dissemination in gram-negative bacteria illustrate new aspects of R plasmid evolution. Antimicrob Agents Chemother 1991,35:1840-1848.
148.Trobos M, Christensen H, Sunde M,et al. Characterization of sulphonamide-resistant Escherichia coli using comparison of sul2 gene sequences and multilocus sequence typing. Microbiology.2009,155(Pt 3):831-6.
149.Vinue L, Saenz Y, Rojo-Bezares B, et al, Zarazaga M, Torres C.Genetic environment of sul genes and characterisation of integrons in Escherichia coli isolates of blood origin in a Spanish hospital. Int J Antimicrob Agents.2010, 35(5):492-6.
150.Phuong Hoa PT, Nonaka L, Hung Viet P, Suzuki S.Detection of the sul1, sul2, and sul3 genes in sulfonamide-resistant bacteria from wastewater and shrimp ponds of north Vietnam.Sci Total Environ.2008,405(1-3):377-84.
151.奥斯泊F.,R.布伦特,RE.金斯顿,DD.穆尔,JG.塞德曼,JA.史密斯,K.斯特拉尔.1999.精编分子生物学实验指南(Short Protocolsin Molecular Biology)科学出版社.
152.Ho PL, Wong RC, Chow KH, et al. Distribution of integron-associated trimethoprim-sulfamethoxazole resistance determinants among Escherichia coli from humans and food-producing animals. Lett Appl Microbiol. 2009,49(5):627-34.
153.Infante B, Grape M, Larsson M,et al.Acquired sulphonamide resistance genes in faecal Escherichia coli from healthy children in Bolivia and Peru. Int J Antimicrob Agents.2005,25(4):308-12
154.Barreto A, Guimaraes B, Radhouani H,et al. Detection of antibiotic resistant E. coli and Enterococcus spp. in stool of healthy growing children in Portugal. J Basic Microbiol.2009,49(6):503-12
155.Kadlec K, Schwarz S.Analysis and distribution of class 1 and class 2 integrons and associated gene cassettes among Escherichia coli isolates from swine, horses, cats and dogs collected in the BfT-GermVet monitoring study. J Antimicrob Chemother.2008,62(3):469-73.
156.Woodford N.Rapid characterization of beta-lactamases by multiplex PCR. Methods Mol Biol.2010; 642:181-92.
157.多丽波,王孟滨,程欣弘,等,多重PCR技术检测医院感染大肠埃希菌、肺炎克雷伯菌质粒AmpC酶基因型别,中华医院感染学杂志,2004,14(10)：1094-1097.
158.Jφrgensen RL, Nielsen JB, Friis-Mφller A,et al.Prevalence and molecular characterization of clinical isolates of Escherichia coli expressing an AmpC phenotype.J Antimicrob Chemother.2010,65(3):460-4.
159.Hancock V, Nielsen EM, Krag L,et al.Comparative analysis of antibiotic resistance and phylogenetic group patterns in human and porcine urinary tract infectious Escherichia coli. APMIS.2009,117(11):786-90.
160.Grape M, Sundstrom L, Kronvall G. Sulphonamide resistance gene sul3 found in Escherichia coli isolates from human sources. J Antimicrob Chemother 2003; 52: 1022-4.
161.Frank T, Gautier V, Talarmin A, Bercion R, Arlet G. Characterization of sulfonamide resistance genes and class 1 integron gene cassettes in Enterobacteriaceae, Central African Republic (CAR).J Antimicrob Chemother 2007;59:742-5.
162.Blahna MT, Zalewski CA, Reuer J,The role of horizontal gene transfer in the spread of trimethoprim-sulfamethoxazole resistance among uropathogenic Escherichia coli in Europe and Canada. J Antimicrob Chemother. 2006,57(4):666-72.
163.Antunes, P., J. Machado, J. C. Sousa, et al. Dissemination of sulfonamide resistance genes (sull, sul2, and sul3) in Portuguese Salmonella enterica strains and relation with integrons. Antimicrob. Agents Chemother.2005,49:836-839
164.Hu J, Shi J, Chang H, Li D,et al. Phenotyping and genotyping of antibiotic-resistant Escherichia coli isolated from a natural river basin. Environ Sci Technol.2008,42(9):3415-20.
165.Byrne-Bailey KG, Gaze WH, Kay P, Boxall AB, Hawkey PM, Wellington EM. Prevalence of sulfonamide resistance genes in bacterial isolates from manured agricultural soils and pig slurry in the United Kingdom.Antimicrob Agents Chemother.2009,53(2):696-702.
166.Rayamajhi N, Cha SB, Kang ML, et al.Inter- and intraspecies plasmid-mediated transfer of florfenicol resistance in Enterobacteriaceae isolates from swine.Appl Environ Microbiol.2009,75(17):5700-3.
167.王丽丽,徐建国,脉冲场凝胶电泳技术(PFGE)在分子分型中的应用现状,疾病监测,2006,21(5),276-279.
168.丁水军,脉冲场凝胶电泳技术及其在病原菌分子分型中的应用,中国卫生检验杂志,2009,19(4),962-964.
169.Ogawa K, Yamaguchi K, Suzuki M, et al.Genetic characteristics and antimicrobial resistance of Escherichia coli from Japanese macaques (macaca fuscata) in rural Japan. J Wildl Dis.2011,47(2):261-70.
170.Gibson JS, Cobbold RN, Trott DJ.Characterization of multidrug-resistant Escherichia coli isolated from extraintestinal clinical infections in animals. J Med Microbiol.2010,59(Pt 5):592-8.
171.Weiner M, Dacko J, Osek J:Molecular analysis of enterotoxigenic, Shiga toxigenic and enteroaggregative Escherichia coli strains isolated from suckling piglets with diarrhoea by the use of pulsed-field electrophoresis. Bull Vet Inst Pulawy 2004,48:225-232.
172.Karama M, Johnson RP, Holtslander R, Gyles CL.Phenotypic and genotypic characterization of verotoxin-producing Escherichia coli O103:H2 isolates from cattle and humans. J Clin Microbiol.2008,46(11):3569-75.
173.Wu XY, Chapman T, Trott DJ, et al.:Comparative analysis of virulence genes, genetic diversity, and phylogeny of commensal and enterotoxigenic Escherichia coli isolates from weaned pigs. Appl Environ Microbiol 2007,73:83-91
174.Lee SI, Rayamahji N, Lee WJ, Cha SB, Shin MK, Roh YM, Yoo HS.Genotypes, antibiogram, and pulsed-field gel electrophoresis profiles of Escherichia coli strains from piglets in Korea. J Vet Diagn Invest.2009 Jul;21(4):510-6.
175.Hoyle DV, Yates CM, Chase-Topping ME, et al.Molecular epidemiology of antimicrobial-resistant commensal Escherichia coli strains in a cohort of newborn calves. Appl Environ Microbiol.2005,71(11):6680-8.
176.王晓泉,不同来源多重耐药性沙门氏菌分离株耐药机制和脉冲场凝胶电泳分析[博士学位论文],扬州,扬州大学,2007。
177.Tenover F C,Arbeit R D,Goering R V,et al.Interpreting chromosomal DNA restriction patterns produced by pulsed-field gel electrophoresis:criteria for bacterial strain typing.Journal of Clinical Microbiology,1995,33:2233-2239.
178.Van den Bogaard A E, London N, Driessen C, et al.Antibiotic resistance of faecal Escherichia coli in poultry,poultry farmers and poultry slaughterers.Journal of Antimicrobial Agents,2001,47:763-771.
179.Pereira AS, Andrade SS, Monteiro J, Sader HS, Pignatari AC, Gales AC.Evaluation of the susceptibility profiles, genetic similarity and presence of qnr gene in Escherichia coli resistant to ciprofloxacin isolated in Brazilian hospitals. Braz J Infect Dis.2007 Feb;11(1):40-3.
180.Chang C C,Lin Y H,Chang C F,et al.S.Epidemiologic relationship between fluoroquinolone-resistant Salmonella enterica Serovar Choleraesuis strains isolated from humans and pigs in Taiwan(1997 to 2002).Journal of Clinical Microbiology,2005,43:2798-2804.
181.杨玲丽,陈杖榴,相同耐药谱的11株大肠杆菌的脉冲场电泳分型研究,中兽医医药杂志,2004,4：19-20
182.Yu-Ting Tan, Darren J. Tillett, Lan A.McKay. Molecular strategies for overcoming antibiotic resistance in bacteria. Molecular Medicine Today. 2000.6:309-314
183.Ball P. R.Shales S. W., Chopra I. Plasmid mediated tetracycline resistance in Es-cherichia coli involves increased efflux of theantibiotic. Biochem Biophs Res Commun.1980.93:74-81
184.Nikaido H. Antibiotic resistance caused by gram-negtive multidrug efflux pumps. Cli Effect Dis27(suppl.1) 1998.:S32-41
185.Pao S. S., Paulsen I. T. Saler M. H. Majorfacilitator superfamily. Microbiol. Mol Bi-ol Rev.1998.62:1-32
186.Paulsen I. T. R. A. Skurray, R. Tam et al. The SMR family:a novel family of multidrug efflux protein involved with the efflux of lipophilic drugs. Mol Microbiol.1999.19:1175
187.Saier M. H. R. Tam, A. Reizer et al. Two novel families of bacterial membrane proteinsconcerned with nodulation, cell division and transport. Mol Microbiol. 1994.11:841-847
188.Van Veen H. W. W. N. Konings. The ABC family of multidrug transporters in microrgan-isms. Biochem Biophs Acta.1998.1365:31-36
189.Foster P. L. Adaptive mutation:the use of adversity. Annu Rev Microbiol. 1993.47:467-504
190.Kohler T. Michea-Hamzehpour M. Plesiat P. Differential selection of multidrug efflux systems by quinolones in Pseudomonas aeruginosa. Antimicrob Agents Chemother.1997.41:2540-2543
191.LeClersc J. E. Li B. Payne W. L. et al. High mutation frequencies among Escherichia coli and Salmonella pathogens. Science.1996.274:1208-1211
192.Taddei F. Radman M. Maynard-Smith J. et al. Role of mutator alleles in adaptive evolution. Nature.1997.387:700-702
193.蔡宝立.质粒.微生物学通报.1993.20(1)：53-58.
194.Alavi MR, Ravizee A, Burgess R.et al. Resistance carrying plasmid in a traumatic wound. J Wound Care.2010,19(7):306-10
195.Uma B, Prabhakar K, Rajendran S,et al.Antibiotic Sensitivity and Plasmid Profiles of Escherichia coli Isolated from Pediatric Diarrhea. J Glob Infect Dis. 2009,1(2):107-10.
196. Wang Q, Cheng J, Chen Y, et al.Characterization of a novel AmpC-type plasmid-mediated beta-lactamase from an Escherichia coli strain isolated in China. Curr Microbiol.2008,57(6):558-63.
197.Kehrenberg C Schwara S,Distribution of florfenicol resistance genes fexA and cfr among chloramphenicol-resistant Staphylococcus isolates. Antimirob Agents Chemother.2006;50(4):1156-63.
198.Briggs CE, Fratamico PM. Molecular characterization of an anti- biotic resistance gene cluster of Salmonella typhimurium DT104. Antimicrob AgentsChemother, 1999,43(4):846-849.
199.Koo HJ, Woo GJ.Distribution and transferability of tetracycline resistance determinants in Escherichia coli isolated from meat and meat products. Int J Food Microbiol.2011,28;145(2-3):407-13.
200.Ziebell K, Johnson RP, Kropinski AM,et al.Gene cluster conferring streptomycin, sulfonamide, and tetracycline resistance in Escherichia coli O157:H7 phage types 23,45, and 67. Appl Environ Microbiol.2011,77(5):1900-3.
201. Wan KF, Radu S, Cheah YK,et al.Antibiotic resistance, plasmid profile and RAPD-PCR analysis of enteropathogenic Escherichia coli (EPEC) clinical isolates. Southeast Asian J Trop Med Public Health.2003,34(3):620-6.
202.Shlaes DM, Currie-McCumber C.Dissemination of a plasmid determining multiple antibiotic resistance between two Veterans Administration Medical Centers. Infect Control.1986,7(7):362-4.
203.Bahrmand AR, Velayati AA Antimicrobial resistance pattern and plasmid profile of Salmonella typhi isolated from an outbreak in Tehran province. Scand J Infect Dis.1997;29(3):265-9.
204.Weill FX, Lailler R, Praud K, Emergence of extended-spectrum-beta-lactamase (CTX-M-9)-producing multiresistant strains of Salmonella enterica serotype Virchow in poultry and humans in France. J Clin Microbiol. 2004,42(12):5767-73.
205.Miles TD, McLaughlin W, Brown PD.Antimicrobial resistance of Escherichia coli isolates from broiler chickens and humans. BMC Vet Res.2006,6;2:7.
206.Sidjabat HE, Townsend KM, Hanson ND, et al. Identification of bla(CMY-7) and associated plasmid-mediated resistance genes in multidrug-resistant Escherichia coli isolated from dogs at a veterinary teaching hospital in Australia. J Antimicrob Chemother.2006,57(5):840-8.
207.盛祖嘉主编,微生物遗传学(第二版),北京,科学出版社。
208.包幼迪,细菌的结合转移试验,福建医学院学报增刊,1984；P100-102
209.张莉平,田兆菊,张西雷等,鸡致病性大肠杆菌的质粒DNA指纹图谱分析,山东农业大学学报(自然科学版),2007,38(4)：524-528
210.黄加权,高美英.大肠杆菌耐药现状与耐药质粒分析.中华传染病杂志,1996,14(2)：70-73.
211.江文正,韩文瑜,王世若.猪致病性大肠杆菌的质粒指纹图谱分析[J].中国兽医学报,1998,18(9)：475-478.
212.陆善勇,李康然.鸡源性大肠杆菌质粒指纹图谱及某些生物学特性的研究[J].广西农业大学学报,1993,12(9)：79-8
213.刘书亮,王红宁,陶勇,等.四川省规模化猪场大肠杆菌质粒DNA分析.西南农业学报.2000.13：69-73.
214.赵静,杨汉春.猪源大肠杆菌耐药性质粒的监测研究.黑龙江畜牧兽医.2000.1：6-9.
215.郑鑫,刘清河,刘晓华,王锡香.利用质粒指纹图谱法对大肠杆菌耐药质粒遗传特性的研究.吉林农业大学学报.2003.25(1)：97-101
216.郑巧敏,张秀霞,朱涛等,大肠埃希菌耐药性水平传播实验研究,中国微生态 学学报,2008,2(20)43-42。
217.陈琳,刘建华,陈杖榴等,rmtB阳性猪大肠杆菌及其接合子中Ⅰ类整合子研究,畜牧兽医学报,2010,41(12)：1576-1583
2. Sherwood D,Snodgrass DR,O'Brien AD.Shiga-like toxin production from Escherichia coli associated with calf diarrhoea[J].Vet Rec.1985,116(8):217-218.
3. 陆承平.兽医微生物学.北京：中国农业出版社,2006：215-223.
4. Kappeli U, Hachler H, Giezendanner N, et al. Human infections with non-0157 Shiga toxin-producing Escherichia coli, Switzerland,2000-2009. Emerg Infect Dis.2011,17(2):180-5.
5. Unno T, Han D, Jang J, et al.High diversity and abundance of antibiotic-resistant Escherichia coli isolated from humans and farm animal hosts in Jeonnam Province, South Korea. Sci Total Environ.2010,408(17):3499-506.
6. Ozawa M, Baba K, Asai T.Molecular typing of avian pathogenic Escherichia coli O78 strains in Japan by using multilocus sequence typing and pulsed-field gel electrophoresis. J Vet Med Sci.2010,72(11):1517-20.
7. Wang XM, Liao XP, Liu SG, et al.Serotypes, Virulence Genes, and Antimicrobial Susceptibility of Escherichia coli Isolates from Pigs. Foodborne Pathog Dis. 2011,2. [Epub ahead of print]
8. Checkley SL, Campbell JR, Waldner CL, et al.A retrospective diagnostic laboratory survey of antimicrobial resistance in fecal Escherichia coli isolated from spring calves in western Canada. Can Vet J.2010,51(11):1283-6
9. Ozaki H, Esaki H, Takemoto K,et al.Antimicrobial resistance in fecal Escherichia coli isolated from growing chickens on commercial broiler farms. Vet Microbiol. 2010,23. [Epub ahead of print]
10. Medina A, Horcajo P, Jurado S, et al.Phenotypic and genotypic characterization of antimicrobial resistance in enterohemorrhagic Escherichia coli and atypical enteropathogenic E. coli strains from ruminants. J Vet Diagn Invest. 2011,23(1):91-5.
11. Harada K, Morimoto E, Kataoka Y, et al.Clonal spread of antimicrobial-resistant Escherichia coli isolates among pups in two kennels. Acta Vet Scand. 2011,17;53:11.
12.万根平,黄勇,邓秋连,等,儿童肠道感染致病性大肠埃希菌血清型分布及耐药性研究,实用医学杂志,2010,26(2),310-311
13.谢永强,邓秋连,万根平,等.广州地区儿童感染性腹泻的病原学研究.中国当代儿科杂志,2009,11(2)：107-109.
14.赵兰兰,朱朝敏,张爱华.1997—2006年重庆地区儿童细菌性腹泻病原菌分布与药敏结果分析.中国实用儿科杂志,2008,23(1)：45-49.
15.喻华英,贾桂珍,邹开胜。犊牛腹泻病中大肠杆菌的分离与鉴定,黑龙江畜牧兽医,2006(6),67-68
16. Thorsteinsdottir TR, Haraldsson G, Fridriksdottir V, et al.Prevalence and genetic relatedness of antimicrobial-resistant Escherichia coli isolated from animals, foods and humans in Iceland. Zoonoses Public Health.2010,57(3):189-96.
17.陈明勇,陈德威,曾群辉,等,牦牛肠毒素型大肠杆菌的分离鉴定和某些生物学特性的研究,中国预防兽医学报,2001,24(4)：277-279.
18.陈明勇,张冰 陈德威,等,牦牛致病性大肠杆菌生物学特性研究,中国农业大学学报2001,6(3)：119-122
19. Kaper J B, Nataro J P, Mobley H L. Pathogenic Escherichia coli[J].Nat Rev Microbio,2004,2(2):123-14
20. Garcia PG, Silva VL, Diniz CG. Occurrence and antimicrobial drug susceptibility patterns of commensal and diarrheagenic Escherichia coli in fecal microbiota from children with and without acute diarrhea. J. Microbiol.2011,49(1):46-52.
21. Sack RB.The discovery of cholera-like enterotoxins produced by Escherichia coli causing secretory diarrhoea in humans. Indian J Med Res.2011, 133(2):171-80.
22. Evans DJ, Evans DG.Escherichia Coli in Diarrheal Disease. In:Baron S, editor. Medical Microbiology.4th edition. Galveston (TX):University of Texas Medical Branch at Galveston; 1996. Chapter 25.
23.周凯,郑海洲,边艳青,等,肠产毒性大肠杆菌分子生物学及基因工程疫苗的研究进展,徽生物学杂志,2003,23(5)：44-47
24.王建阳,致病性大肠杆菌和出血性大肠杆菌的研究进展,中国热带医学,2004,4(2)：292-294
25. Yin X, Zhu J, Feng Y, et al.Differential Gene Expression and Adherence of Escherichia coli O157:H7 In Vitro and in Ligated Pig Intestines. PLoS One.2011, 28;6(2):e17424.
26.裴迎新,王晓平,闫滨,等,分子分型方法在肠出血性大肠杆菌检测中的应用,中国公共卫生管理,2009,25(4),415-417
27.张志果,罗寒,杨好施,等.一起由侵袭性大肠杆菌引起的食物中毒.中华流行病学杂志,1987,8(4)：250.
28. Xu JG, Cheng B, Wen X, et al.High-pathogenicity island of Yersinia spp. in Escherichia coli strains isolated from diarrhea patients in China. J Clin Microbiol. 2000,38(12):4672-5.
29.沈宪文,仔猪大肠杆菌耐药性分析及耐磺胺类药物基因的检测[学位论文],长春,吉林大学,2003。
30. IIalnmerum AM, Detection of sull, sul2 and sul3 in sulphonamide resistant Eseheriehia coli isolates obtained from healthy humans, pork and pigs in Demark. Int J Food Microbiol.,2006,106(2):235-237
31.羊云飞,王红宁,谭雪梅,等,二重PCR检测猪、鸡源致病性大肠杆菌、沙门氏菌磺胺类耐药基因(Sull、Sul2、Sul3)的研究,畜牧兽医学报2007,38(10)：1088-1092
32.周万蓉,王红宁,张安云,等,猪和野生动物源大肠杆菌及沙门菌中磺胺类药物耐药基因的检测,中国兽医科学2007,37(04)：287-29
33. Wu S, Dalsgaard A, Hammerum AM, et al.Prevalence and characterization of plasmids carrying sulfonamide resistance genes among Escherichia coli from pigs, pig carcasses and human. Acta Vet Scand.2010,30;52:47
34.康立超,黄新,何延华,等,犊牛耐药性大肠杆菌的分离鉴定,新疆农垦科技,2010,2：53-54
35. Aslam M, Stanford K, McAllister TA.Characterization of antimicrobial resistance and seasonal prevalence of Escherichia coli O157:H7 recovered from commercial feedlots in Alberta, Canada. Lett Appl Microbiol.2010,50(3):320-6.
36. Swedberg, G, C. Fermer, and O. Skold.1993. Point mutations in the dihydropteroate synthase gene causing sulfonamide resistance. Adv. Exp. Med. Biol.338:555-558.
37. Vedantam, G., G. G. Guay, N. E. Austria, S. Z. Doktor, and B. P. Nichols. Characterization of mutations contributing to sulfathiazole resistance in Escherichia coli. Antimicrob. Agents Chemother.1998.42:88-93.
38. Skold O. Sulfonamide resistance:mechanisms and trends. Drug Resist Update, 20003:155-60.
39. Skold O. R-factor-mediated resistance to sulfonamides by a plasmid-borne, drug-resistant dihydropteroate synthase. Antimicrob Agents Chemother 1976; 9: 49-54.
40. Radstrom, P., and G Swedberg. RSF1010 and a conjugative plasmid contain sulll, one of two known genes for plasmid-borne sulfonamide resistance dihydropteroate synthase. Antimicrob. Agents Chemother.1988.32:1684-1692.
41. Sundstrom, L., P. Radstrom, G. Swedberg, and O. Skold. Site-specific recombination promotes linkage between trimethoprim- and sulfonamide resistance genes. Sequence characterization of dhfrV and sull and a recombination active locus of Tn21.1988.Mol. Gen. Genet.213:191-201.
42. Swedberg, G., and O. Skold. Characterization of different plasmid-borne dihydropteroate synthases mediating bacterial resistance to sulfonamides. J. Bacteriol.1980.142:1-7.
43. Enne VI, King A, Livermore DM, Hall LM. Sufonamide resistance in Haemophilus influenzae mediated by acquisition of sul2 or a short insertion in chromosomal folP. Antimicrob Agents Chemother 2002;46:1934-9.
44. Perreten V, Boerlin P. A new sulfonamide resistance gene (sul3) in Escherichia coli is widespread in the pig population of Switzerland. Antimicrob Agents Chemother 2003;47:1169-72.
45. Swedberg G, Skold O. Plasmid-borne sulfonamide resistance determinants studied by restriction enzyme analysis. J Bacteriol 1983; 153:1228-1237.
46. Radstrom, P., G. Swedberg, and O. Skold. Genetic analyses of sulfonamide resistance and its dissemination in gram-negative bacteria illustrate new aspects of R plasmid evolution. Antimicrob. Agents Chemother.1991.35:1840-1848.
47. Van Treeck UF, Schmidt F,Wiedemann B. Molecular nature of a streptomycin and sulfonamide resistance plasmid (pBPI) prevalent in clinical Escherichia coli strains and integration of an ampicillin resistance transposon (TnA).Antimicrob Agents Chemother 1981;19:371-380.
48. Scholz P, Haring V, Wittmannliebold B, Ashman K, Bagdasarian M, Scherzinger E. Complete nucleotide-sequence and gene organization of the broadhost-range plasmid RSF1010. Gene1989;75:271-88.
49. Liu, J., Keelan, P., Bennett, P. M., Enne, V. I. Characterization of a novel macrolide efflux gene, mef(B), found linked to sul3 in porcine Escherichia coli.J Antimicrob Chemother 2009,63:423-426
50. Boerlin, P., R. Travis, C. L. Gyles, R. et al. Friendship, and M. Archambault. Antimicrobial resistance and virulence genes of Escherichia coli isolates from swine in Ontario. Appl. Environ. Microbiol.2005.71:6753-6761.
51. Kerrn MB, Klemmensen T, Frimodt-Mφller N, Espersen F.Susceptibility of Danish Escherichia coli strains isolated from urinary tract infections and bacteraemia, and distribution of sul genes conferring sulphonamide resistance. J Antimicrob Chemother 2002;50:513-6.
52. Kozak GK, Pearl DL, Parkman J, Reid-Smith RJ, Deckert A, Boerlin P. Antimicrobial Resistance in Escherichia coli Isolates from Swine and Wild Small Mammals in the Proximity of Swine Farms and in Natural Environments in Ontario, Canada.Appl Environ Microbiol.2009,75(18):5999-6001.
53. Guerra, B., E. Junker, and R. Helmuth. Incidence of the recently described sulfonamide resistance gene sul3 among German Salmonella enterica strains isolated from livestock and food. Antimicrob. Agents Chemother. 2004.48:2712-2715.
54. Koljalg S, Truusalu K, Vainumae I,et al.Persistence of Escherichia coli clones and phenotypic and genotypic antibiotic resistance in recurrent urinary tract infections in childhood. Clin Microbiol.2009,47(1):99-105.
55. Bean, D. C., D. M. Livermore, I. Papa, and L. M. C. Hall. Resistance among Escherichia coli to sulphonamides and other antimicrobials now little used in man. J. Antimicrob. Chemother.2005.56:962-964.
56. Bean, D. C., Livermore, D. M., Hall, L. M. C. Plasmids Imparting Sulfonamide Resistance in Escherichia coli:Implications for Persistence. Antimicrob. Agents Chemother.2009,53:1088-1093
57. Aminov R, Mackie RI. Evolution and ecology of antibiotic resistance genes. FEMS Microbiol Lett 2007; 271:147-61.
58.羊云飞,多重PCR检测沙门氏菌、大肠杆菌对磺胺类、氯霉素类药物耐药基因的研究[学位论文],雅安,四川农业大学,2004
59.张铁,王春光,王谦,猪源大肠杆菌的分离、鉴定及耐药性监测,中国农学通报,2005,12：34-36
60.杜向党,李新生,张素梅,等,鸡源大肠杆菌氟苯尼考耐药基因floR的分子检测,河南农业大学学报,2007,41(2)：20-23
61.郑朝朝,刘聚祥,李辉,等,鸡源、猪源大肠杆菌氟苯尼考耐药基因flor的克隆与序列分析,华北农学报,2010,25(5)：72-75.
62. Kim E, Aoki T. Sequence analysis of the florfenicol resistance gene encoded in the transferable R-plasmid of a fish pathogen. Microbiol Immuno,l 1996,40(9): 665-669.
63. Briggs CE, Fratamico PM. Molecular characterization of an antibiotic resistance gene cluster of Salm onella typhim urium DT104[J]. Antimicrob Agents Chemother,1999,43 (4):846-849
64. Bolton L, KelleyL, LeeM,etal.Detection ofmulti-drug resistant Salmonella entericaserotypeTyphimurium DT104 based on a gene which confers cross-resistance to florfenicol and chloramphenicol. JClinMicrobio,l 1999,37(5): 1348-1351.
65. Kehrenberg C, Meunier D, Targant H, et al.Plasmid-mediated florfenicol resistance in Pasteurella trehalosi.J Antimicrob Chemother.2006;58(1):13-7.
66. Kehrenberg C, Schwarz S.Plasmid-borne florfenicol resistance in Pasteurella multocida.J Antimicrob Chemother.2005;55(5):773-5.
67. Doublet, B., S. Schwarz, E. Nussbeck,et al. Molecular analysis of chromosomally florfenicol resistant Escherichia coli isolates from France and Germany. J. Antimicrob. Chemother.2002.49:49-54.
68. Blickwede, M., Schwarz, S. Molecular analysis of florfenicol-resistant Escherichia coli isolates from pigs. J Antimicrob Chemother 2004,53:58-64
69. Li XS, Wang GQ, Du XD, et al.Antimicrobial susceptibility and molecular detection of chloramphenicol and florfenicol resistance among Escherichia coli isolates from diseased chickens.J Vet Sci.2007,8(3):243-7.
70. Meunier D, Jouy E, Lazizzera C, et al. Plasmid-borne florfenicol and ceftiofur resistance encoded by the floR and blaCMY-2 genes in Escherichia coli isolates from diseased cattle in France.J Med Microbiol.2010,7. [Epub ahead of print]
71. White, D. G., C. Hudson, J. J. Maurer, et al. Sherwood. Characterization of chloramphenicol and florfenicol resistance in Escherichia coli associated with bovine diarrhea. J. Clin. Microbiol.2000.38:4593-4598.
72. Cloeckaert, A., S. Baucheron, and E. Chaslus-Dancla. Nonenzymatic chloramphenicol resistance mediated by IncC plasmid R55 is encoded by a floR gene variant. Antimicrob. Agents Chemother.2001.45:2381-2382.
73. Schwartz DC, Cantor CR-Separation ofyeast chromosome-sized DNAs by pulsed field gradient gel electrophoresis. Cel,l 1984,37:67-75.
74.王丽丽,徐建国,脉冲场凝胶电泳技术(PFGE)在分子分型中的应用现状,疾病监测,2006,21(5),276-279.
75.丁水军,脉冲场凝胶电泳技术及其在病原菌分子分型中的应用,中国卫生检验杂志,2009,19(4),962-964.
76. Beadle J,WrighMt,McNeelyL,et al-Electrophoretic karyotype analysis in fungi.Adv App Ml icrobio,l 2003,53:243-270.
77.边银丙,罗信昌,脉冲电泳技术及其在食用菌研究中的应用,食用菌学报,1996,3(2)：45-50
78. Lai E, Birren BW, Clark SM, et al. Pulsed field gel electrophoresis Biotechniques,1989,7(1):34-42
79. ZhangTY, Smith CL,CantorCR-Secondary pulsed field gel electrophoresis:a new method for faster separation of larger DNA molecules[J]·Nucleic Acids Research, 1991,19(6):1291-1296
80.时连根,PFGE技术及其在昆虫病原真菌研究中的应用,微生物学通报,2000,27(3)：212-215
81. Martinez-Urtaza Jaime,Lozano-Leon Antonio,DePaola Angelo,et al.Characterization of Pathogenic Vibrio parahaemolyticusIsolates from Clinical Sources in Spain and Comparison withAsian and North American Pandemic Isolates.J Clin Micro-biol,2004,42:4672-4678
82.康梅,申艳娜,脉冲场凝胶电泳在医院内感染大肠杆菌的分子流行病学的应用研究,华西医学,2002；17(1),34-35。
83.周晓明,卢林耿,卫国荣,等,脉冲场电泳进行E.coli 0157的分型,复旦学报(医学科学版),2001,28(1)：71
84.胡云建,杜迪君,张秀珍,产超广谱p-内酰胺酶大肠埃希菌的耐药性及脉冲场电泳分型研究,中华医学感染学杂志,2000,10(2)：154.
85. Katsunuma Y, Hanazumi M, Fujisaki H, Minato H, Kataoka Y, Sawada T, Hashimoto Y, Yonemochi C.Comparison of pulsed-field gel electrophoresis patterns of antimicrobial-resistant Escherichia coli and enterococci isolates from the feces of livestock and livestock farmers in Japan. J Gen Appl Microbiol. 2008,54(1):39-50.
86.杨玲丽,陈杖榴,刘健华,等,动物、环境及饲养员多重耐药大肠杆菌的PFGE分型研究,中国农业科学2005,39(12)：2597-2602。
87. Donabedian S M,Thal L A,Hershberger E,et al.Molecular characterization of gentamicin-resistant Enterococci in theUnited States:evidence of spread from animals to humans through food.Journal of Clinical Microbiology,2003,41:1109-1113.
88.黄彦,孙贵娟,唐振柱,等,出血性大肠杆菌0157：H7的脉冲场凝胶电泳分型方法研究,应用预防医学,2007,13(1),19-22.
89.李聪智,谭德明.聚合酶链反应检测细菌16S rRNA/16S rDNA,湖南医学学报,1999,16(2)：88-89.
90.金鑫,李妍,陈代杰,PCR扩增rRNA基因在细菌菌种鉴定中的应用,国外医药抗生素分册,2003,24(5)：223.
91.周爆,16S rRNA/16S rDNA序列分析法在医学微生物鉴定中的应用,生物技术通讯,1999,10(4)：297-305.
92.J.萨姆布鲁克,D.W.拉塞尔.著,黄培唐等译,分子克隆实验指南(第三版).科学出版社.2002.
93.R.E.布坎南,N.E吉本斯等伯杰细菌鉴定手册(第八版),450-452.
94. Drancourt.M, PBerger,D.Raoult.2004. Systematic 16S rRNA Gene Sequencing of Atypical Clinical Isolates Identified 27 New Bacterial Species Associated with Hunans. Jurnal of Clinical Microbiology.5:5:2197-2202
95.时全,黄新明,李朝阳,等,致泻大肠埃希菌感染在腹泻病中地位的研究,中国卫生检验杂志,2005,15(1)：5-8.
96. Alikhani M Y, Mirsalehian A, Aslani M M. Detection of typical and atypical enteropathogenic Escherichia coli (EPEC) in Iranian children with and without diarrhoea. J Med Microbiol,2006,55 (9):1159-1163.
97. Vignoli R, Varela G, Mota M I, et al. Enteropathogenic Escherichia coli strains carrying genes encoding the PER-2 and TEM-116 extended-spectrum beta-lactamases isolated from children with diarrhea in Uruguay. J Clin Microbiol,2005,43 (6):2940-2943.
98.杨锦红,任春阳,王军.肠致病性大肠埃希菌血清型分布及耐药性分析,实验与检验医学,2008,26(2)：143-144.
99.叶迎春,赵世鸿,凌体淑.三种菌种的保存比较,中国吴诊学杂志,2004,4(3)386-389.
100.方光远,张志成,晏文梅.几种不同条件下细菌菌株保存试验。金陵科技学院学报。2004,9,20(3)
101.张绪利,方晓红,贾瑛.用液体石蜡保存菌种的新方法.临床检验杂志.2005,(23)5,362-364.
102.黄霞云,菌种保存方法的改进.广州医学院学报.1999,(17)1,73-74
103.房海主编,大肠埃希氏菌,石家庄：河北科学技术出版社,1997
104.方光远,金兰梅,闻发全,等,078败血型犊牛大肠杆菌的分离和鉴定,金陵科技学院学报,2007,23(1)：105-107
105.方光远,张姝,张玉红,等。腹泻犊牛大肠杆菌的分离鉴定和药敏试验。中国兽医杂志,2008,44(10),33-34.
106.陈明勇,张冰,陈德成,等,西藏地区牦牛致病性大肠杆菌的分离鉴定,中国预防兽医学报,2001,23(5)：389-390.
107.徐明举,陈建新,李寸欣,等,引起犊牛腹泻的致病性大肠杆菌的分离鉴定,兽医科技,2009,11：88-89。
108.胡智斌,宋念华,李德学,等,,湖北省犊牛致病性大肠杆菌病的检测与分离鉴定,湖北农业科学,2006,45(3)：362-364
109.斯木吉德,敖日格乐,王纯洁,等,6种血清型牛源致病性大肠杆菌的体外抑菌效果研究,黑龙江畜牧兽医,2009,9：69-70
110.Graves AK, Liwimbi L, Israel DW, van Heugten E, Robinson B, Cahoon CW, Lubbers JF.Distribution of ten antibiotic resistance genes in E. coli isolates from swine manure, lagoon effluent and soil collected from a lagoon waste application field. Folia Microbiol (Praha).2011,29. [Epub ahead of print]
111.朱岩丽,康丽,杨其峰,等,泰安周边地区鸡致病性大肠杆菌的分离鉴定与药敏试验,山东畜牧兽医,2007,15(2)：67-68.
112.刘明春,于立辉,何剑斌,等。犊牛腹泻病原菌的分离鉴定及敏感药物筛选。黑龙江畜牧兽医,2005,(12)：42-43
113.Sarma JB, Bhattacharya PK, Kalita D, et al.Multidrug-resistant Enterobacteriaceae including metallo-β-lactamase producers are predominant pathogens of healthcare-associated infections in an Indian teaching hospital. Indian J Med Microbiol.2011,29(1):22-7.
114.王丽荣,胡婕,卢晓辉,等,豫北地区致病性鸡大肠杆菌的分离鉴定,中国 兽医杂志,2007,55(11)：38-39.
115.吴信明,连洪梅,王艳,等,38株鸭源大肠杆菌的分离鉴定与药敏试验,中国畜牧兽医,2010,37(10)：178-180
116.王红宁,刘书亮,陶勇,等,规模化猪场致病性大肠杆菌、沙门氏菌药敏区系调查,西南农业学报,2000,13：84-90.
117.Smith MG, Jordan D, Chapman TA, et al.Antimicrobial resistance and virulence gene profiles in multi-drug resistant enterotoxigenic Escherichia coli isolated from pigs with post-weaning diarrhoea. Vet Microbiol.2010,26; 145(3-4):299-307.
118.Jiang HX, Lii DH, Chen ZL, et al.High prevalence and widespread distribution of multi-resistant Escherichia coli isolates in pigs and poultry in China. Vet J.2011, 187(1):99-103.
119.Scaria J, Warnick LD, Kaneene JB, et al.Comparison of phenotypic and genotypic antimicrobial profiles in Escherichia coli and Salmonella enterica from the same dairy cattle farms. Mol Cell Probes.2010,24(6):325-45.
120.Vinson HM, Gautam A, Olet S, Gibbs PS, Barigye R.Molecular analysis of porin gene transcription in heterogenotypic multidrug-resistant Escherichia coli isolates from scouring calves. J Antimicrob Chemother.2010,65(9):1926-35.
121.Yue L, Jiang HX, Liao XP, et al.Prevalence of plasmid-mediated quinolone resistance qnr genes in poultry and swine clinical isolates of Escherichia coli. Vet
122.Delsol AA, Halfhide DE, Bagnall MC, et al.Persistence of a wild type Escherichia coli and its multiple antibiotic-resistant (MAR) derivatives in the abattoir and on chilled pig carcasses. Int J Food Microbiol.2010, 140(2-3):249-53.
123.Zhao J, Chen Z, Chen S, et al. Prevalence and dissemination of oqxAB in Escherichia coli isolates from animals, farmworkers, and the environment. Antimicrob Agents Chemother.2010,54(10):4219-24.
124.Zhang XY, Ding LJ, Yue J.Occurrence and characteristics of class 1 and class 2 integrons in resistant Escherichia coli isolates from animals and farm workers in northeastern China. Microb Drug Resist.2009,15(4):323-8.
125.Alali WQ, Scott HM, Harvey RB, et al.Longitudinal study of antimicrobial resistance among Escherichia coli isolates from integrated multisite cohorts of humans and swine. Appl Environ Microbiol.2008,74(12):3672-81.
126.Phongpaichit S, Liamthong S, Mathew AG, et al.Prevalence of class 1 integrons in commensal Escherichia coli from pigs and pig farmers in Thailand. J Food Prot. 2007,70(2):292-9.
127.Scott HM, Campbell LD, Harvey RB, et al.Patterns of antimicrobial resistance among commensal Escherichia coli isolated from integrated multi-site housing and worker cohorts of humans and swine. Foodborne Pathog Dis.2005, 2(1):24-37.
128.Gebreyes WA, Thakur S.Multidrug-resistant Salmonella enterica serovar Muenchen from pigs and humans and potential interserovar transfer of antimicrobial resistance. Antimicrob Agents Chemother.2005,49(2):503-11.
129.汪洋,易力,王红宁,等,川西北牦牛致病性大肠杆菌的分离鉴定及药敏试验,中国兽医杂志,2008,44(5)：36-37
130.叶应妩、王毓三,全国临床检验操作规程(第二版).东南大学出版社,1997,62-567
131.戴白英,刘裕昆,实用抗菌药物学(第二版),人民卫生出版社,1998,203-20
132. CLSI. Performance Standards for Antimicrobial Susceptibility Testing; Nineteenth Informational Supplement. Wayne, PA:Clinical and Laboraory Stadards Instiute; 2009.
133.邢艳苹,王瑜,杨峰,朱僧,等,动物源性大肠杆菌耐药性分析,吉林畜牧兽医,2010,31(11)：7-10
134.于桂阳,湖南省规模化猪场猪源大肠杆菌耐药性调查,猪病防控,2010,11：23-26
135.魏雅静,林居纯,毕师诚,等,四川省不同地区猪源大肠杆菌耐药性调查,安徽农业科学,2011,39(1)：273-274。
136.苟清碧,聂奎,鸭源致病性大肠杆菌的分离鉴定及耐药性分析,黑龙江畜牧 兽医,2010,10,：92-93
137.廖娟,王红宁,黄勇,等,牦牛致病性大肠杆菌的分离鉴定及药敏试验,畜牧与兽医,2006,8(8)：49-50
138.黑占珠,谢仲强,青海果洛州德昂乡屠宰牦牛源大肠杆菌耐药性观察,青海畜牧兽医杂志,2005,35(2)：3-4
139.崔保安,王学斌,李新生,犊牛腹泻病原分离鉴定及中药防治试验,中国兽医杂志,1998,24(10)：40-41
140.Gad GF, Mohamed HA, Ashour HM.Aminoglycoside resistance rates, phenotypes, and mechanisms of gram-negative bacteria from infected patients in Upper Egypt. PLoS One.2011 Feb 17; 6(2):e17224.
141.Japoni A, Vazin A, Hamedi M, et al..Multidrug-resistant bacteria isolated from intensive-care-unit patient samples. Brazilian Journal Infect Dis. 2009,3(2):118-22.
142.桓新,卢大雷等.健康人群与家鸡大肠杆菌的耐药性分析.实用预防医学.2007,14(10)1648-1649.
143.白迎春,李采青,张立永,等,临床分离人源大肠杆菌耐药性的测定,河北北方学院学报(医学版),2010,27(2)：12-15
144.Stenske KA, Bemis DA, Gillespie BE,et al.Comparison of clonal relatedness and antimicrobial susceptibility of fecal Escherichia coli from healthy dogs and their owners. Am J Vet Res.2009,70(9):1108-16
145.穆新林.超广谱β-内酰胺酶细菌下呼吸道感染的监测及危险因素分析,中华医院感染学杂志,2002,12(2)：94-96
146.Trobos M, Jakobsen L, Olsen KE,et al. Prevalence of sulphonamide resistance and class 1 integron genes in Escherichia coli isolates obtained from broilers, broiler meat, healthy humans and urinary nfections in Denmark. Int J Antimicrob Agents 2008,32:367-369.
147.Radstrom P, Swedberg G, Skold O:Genetic analyses of sulfonamide resistance and its dissemination in gram-negative bacteria illustrate new aspects of R plasmid evolution. Antimicrob Agents Chemother 1991,35:1840-1848.
148.Trobos M, Christensen H, Sunde M,et al. Characterization of sulphonamide-resistant Escherichia coli using comparison of sul2 gene sequences and multilocus sequence typing. Microbiology.2009,155(Pt 3):831-6.
149.Vinue L, Saenz Y, Rojo-Bezares B, et al, Zarazaga M, Torres C.Genetic environment of sul genes and characterisation of integrons in Escherichia coli isolates of blood origin in a Spanish hospital. Int J Antimicrob Agents.2010, 35(5):492-6.
150.Phuong Hoa PT, Nonaka L, Hung Viet P, Suzuki S.Detection of the sul1, sul2, and sul3 genes in sulfonamide-resistant bacteria from wastewater and shrimp ponds of north Vietnam.Sci Total Environ.2008,405(1-3):377-84.
151.奥斯泊F.,R.布伦特,RE.金斯顿,DD.穆尔,JG.塞德曼,JA.史密斯,K.斯特拉尔.1999.精编分子生物学实验指南(Short Protocolsin Molecular Biology)科学出版社.
152.Ho PL, Wong RC, Chow KH, et al. Distribution of integron-associated trimethoprim-sulfamethoxazole resistance determinants among Escherichia coli from humans and food-producing animals. Lett Appl Microbiol. 2009,49(5):627-34.
153.Infante B, Grape M, Larsson M,et al.Acquired sulphonamide resistance genes in faecal Escherichia coli from healthy children in Bolivia and Peru. Int J Antimicrob Agents.2005,25(4):308-12
154.Barreto A, Guimaraes B, Radhouani H,et al. Detection of antibiotic resistant E. coli and Enterococcus spp. in stool of healthy growing children in Portugal. J Basic Microbiol.2009,49(6):503-12
155.Kadlec K, Schwarz S.Analysis and distribution of class 1 and class 2 integrons and associated gene cassettes among Escherichia coli isolates from swine, horses, cats and dogs collected in the BfT-GermVet monitoring study. J Antimicrob Chemother.2008,62(3):469-73.
156.Woodford N.Rapid characterization of beta-lactamases by multiplex PCR. Methods Mol Biol.2010; 642:181-92.
157.多丽波,王孟滨,程欣弘,等,多重PCR技术检测医院感染大肠埃希菌、肺炎克雷伯菌质粒AmpC酶基因型别,中华医院感染学杂志,2004,14(10)：1094-1097.
158.Jφrgensen RL, Nielsen JB, Friis-Mφller A,et al.Prevalence and molecular characterization of clinical isolates of Escherichia coli expressing an AmpC phenotype.J Antimicrob Chemother.2010,65(3):460-4.
159.Hancock V, Nielsen EM, Krag L,et al.Comparative analysis of antibiotic resistance and phylogenetic group patterns in human and porcine urinary tract infectious Escherichia coli. APMIS.2009,117(11):786-90.
160.Grape M, Sundstrom L, Kronvall G. Sulphonamide resistance gene sul3 found in Escherichia coli isolates from human sources. J Antimicrob Chemother 2003; 52: 1022-4.
161.Frank T, Gautier V, Talarmin A, Bercion R, Arlet G. Characterization of sulfonamide resistance genes and class 1 integron gene cassettes in Enterobacteriaceae, Central African Republic (CAR).J Antimicrob Chemother 2007;59:742-5.
162.Blahna MT, Zalewski CA, Reuer J,The role of horizontal gene transfer in the spread of trimethoprim-sulfamethoxazole resistance among uropathogenic Escherichia coli in Europe and Canada. J Antimicrob Chemother. 2006,57(4):666-72.
163.Antunes, P., J. Machado, J. C. Sousa, et al. Dissemination of sulfonamide resistance genes (sull, sul2, and sul3) in Portuguese Salmonella enterica strains and relation with integrons. Antimicrob. Agents Chemother.2005,49:836-839
164.Hu J, Shi J, Chang H, Li D,et al. Phenotyping and genotyping of antibiotic-resistant Escherichia coli isolated from a natural river basin. Environ Sci Technol.2008,42(9):3415-20.
165.Byrne-Bailey KG, Gaze WH, Kay P, Boxall AB, Hawkey PM, Wellington EM. Prevalence of sulfonamide resistance genes in bacterial isolates from manured agricultural soils and pig slurry in the United Kingdom.Antimicrob Agents Chemother.2009,53(2):696-702.
166.Rayamajhi N, Cha SB, Kang ML, et al.Inter- and intraspecies plasmid-mediated transfer of florfenicol resistance in Enterobacteriaceae isolates from swine.Appl Environ Microbiol.2009,75(17):5700-3.
167.王丽丽,徐建国,脉冲场凝胶电泳技术(PFGE)在分子分型中的应用现状,疾病监测,2006,21(5),276-279.
168.丁水军,脉冲场凝胶电泳技术及其在病原菌分子分型中的应用,中国卫生检验杂志,2009,19(4),962-964.
169.Ogawa K, Yamaguchi K, Suzuki M, et al.Genetic characteristics and antimicrobial resistance of Escherichia coli from Japanese macaques (macaca fuscata) in rural Japan. J Wildl Dis.2011,47(2):261-70.
170.Gibson JS, Cobbold RN, Trott DJ.Characterization of multidrug-resistant Escherichia coli isolated from extraintestinal clinical infections in animals. J Med Microbiol.2010,59(Pt 5):592-8.
171.Weiner M, Dacko J, Osek J:Molecular analysis of enterotoxigenic, Shiga toxigenic and enteroaggregative Escherichia coli strains isolated from suckling piglets with diarrhoea by the use of pulsed-field electrophoresis. Bull Vet Inst Pulawy 2004,48:225-232.
172.Karama M, Johnson RP, Holtslander R, Gyles CL.Phenotypic and genotypic characterization of verotoxin-producing Escherichia coli O103:H2 isolates from cattle and humans. J Clin Microbiol.2008,46(11):3569-75.
173.Wu XY, Chapman T, Trott DJ, et al.:Comparative analysis of virulence genes, genetic diversity, and phylogeny of commensal and enterotoxigenic Escherichia coli isolates from weaned pigs. Appl Environ Microbiol 2007,73:83-91
174.Lee SI, Rayamahji N, Lee WJ, Cha SB, Shin MK, Roh YM, Yoo HS.Genotypes, antibiogram, and pulsed-field gel electrophoresis profiles of Escherichia coli strains from piglets in Korea. J Vet Diagn Invest.2009 Jul;21(4):510-6.
175.Hoyle DV, Yates CM, Chase-Topping ME, et al.Molecular epidemiology of antimicrobial-resistant commensal Escherichia coli strains in a cohort of newborn calves. Appl Environ Microbiol.2005,71(11):6680-8.
176.王晓泉,不同来源多重耐药性沙门氏菌分离株耐药机制和脉冲场凝胶电泳分析[博士学位论文],扬州,扬州大学,2007。
177.Tenover F C,Arbeit R D,Goering R V,et al.Interpreting chromosomal DNA restriction patterns produced by pulsed-field gel electrophoresis:criteria for bacterial strain typing.Journal of Clinical Microbiology,1995,33:2233-2239.
178.Van den Bogaard A E, London N, Driessen C, et al.Antibiotic resistance of faecal Escherichia coli in poultry,poultry farmers and poultry slaughterers.Journal of Antimicrobial Agents,2001,47:763-771.
179.Pereira AS, Andrade SS, Monteiro J, Sader HS, Pignatari AC, Gales AC.Evaluation of the susceptibility profiles, genetic similarity and presence of qnr gene in Escherichia coli resistant to ciprofloxacin isolated in Brazilian hospitals. Braz J Infect Dis.2007 Feb;11(1):40-3.
180.Chang C C,Lin Y H,Chang C F,et al.S.Epidemiologic relationship between fluoroquinolone-resistant Salmonella enterica Serovar Choleraesuis strains isolated from humans and pigs in Taiwan(1997 to 2002).Journal of Clinical Microbiology,2005,43:2798-2804.
181.杨玲丽,陈杖榴,相同耐药谱的11株大肠杆菌的脉冲场电泳分型研究,中兽医医药杂志,2004,4：19-20
182.Yu-Ting Tan, Darren J. Tillett, Lan A.McKay. Molecular strategies for overcoming antibiotic resistance in bacteria. Molecular Medicine Today. 2000.6:309-314
183.Ball P. R.Shales S. W., Chopra I. Plasmid mediated tetracycline resistance in Es-cherichia coli involves increased efflux of theantibiotic. Biochem Biophs Res Commun.1980.93:74-81
184.Nikaido H. Antibiotic resistance caused by gram-negtive multidrug efflux pumps. Cli Effect Dis27(suppl.1) 1998.:S32-41
185.Pao S. S., Paulsen I. T. Saler M. H. Majorfacilitator superfamily. Microbiol. Mol Bi-ol Rev.1998.62:1-32
186.Paulsen I. T. R. A. Skurray, R. Tam et al. The SMR family:a novel family of multidrug efflux protein involved with the efflux of lipophilic drugs. Mol Microbiol.1999.19:1175
187.Saier M. H. R. Tam, A. Reizer et al. Two novel families of bacterial membrane proteinsconcerned with nodulation, cell division and transport. Mol Microbiol. 1994.11:841-847
188.Van Veen H. W. W. N. Konings. The ABC family of multidrug transporters in microrgan-isms. Biochem Biophs Acta.1998.1365:31-36
189.Foster P. L. Adaptive mutation:the use of adversity. Annu Rev Microbiol. 1993.47:467-504
190.Kohler T. Michea-Hamzehpour M. Plesiat P. Differential selection of multidrug efflux systems by quinolones in Pseudomonas aeruginosa. Antimicrob Agents Chemother.1997.41:2540-2543
191.LeClersc J. E. Li B. Payne W. L. et al. High mutation frequencies among Escherichia coli and Salmonella pathogens. Science.1996.274:1208-1211
192.Taddei F. Radman M. Maynard-Smith J. et al. Role of mutator alleles in adaptive evolution. Nature.1997.387:700-702
193.蔡宝立.质粒.微生物学通报.1993.20(1)：53-58.
194.Alavi MR, Ravizee A, Burgess R.et al. Resistance carrying plasmid in a traumatic wound. J Wound Care.2010,19(7):306-10
195.Uma B, Prabhakar K, Rajendran S,et al.Antibiotic Sensitivity and Plasmid Profiles of Escherichia coli Isolated from Pediatric Diarrhea. J Glob Infect Dis. 2009,1(2):107-10.
196. Wang Q, Cheng J, Chen Y, et al.Characterization of a novel AmpC-type plasmid-mediated beta-lactamase from an Escherichia coli strain isolated in China. Curr Microbiol.2008,57(6):558-63.
197.Kehrenberg C Schwara S,Distribution of florfenicol resistance genes fexA and cfr among chloramphenicol-resistant Staphylococcus isolates. Antimirob Agents Chemother.2006;50(4):1156-63.
198.Briggs CE, Fratamico PM. Molecular characterization of an anti- biotic resistance gene cluster of Salmonella typhimurium DT104. Antimicrob AgentsChemother, 1999,43(4):846-849.
199.Koo HJ, Woo GJ.Distribution and transferability of tetracycline resistance determinants in Escherichia coli isolated from meat and meat products. Int J Food Microbiol.2011,28;145(2-3):407-13.
200.Ziebell K, Johnson RP, Kropinski AM,et al.Gene cluster conferring streptomycin, sulfonamide, and tetracycline resistance in Escherichia coli O157:H7 phage types 23,45, and 67. Appl Environ Microbiol.2011,77(5):1900-3.
201. Wan KF, Radu S, Cheah YK,et al.Antibiotic resistance, plasmid profile and RAPD-PCR analysis of enteropathogenic Escherichia coli (EPEC) clinical isolates. Southeast Asian J Trop Med Public Health.2003,34(3):620-6.
202.Shlaes DM, Currie-McCumber C.Dissemination of a plasmid determining multiple antibiotic resistance between two Veterans Administration Medical Centers. Infect Control.1986,7(7):362-4.
203.Bahrmand AR, Velayati AA Antimicrobial resistance pattern and plasmid profile of Salmonella typhi isolated from an outbreak in Tehran province. Scand J Infect Dis.1997;29(3):265-9.
204.Weill FX, Lailler R, Praud K, Emergence of extended-spectrum-beta-lactamase (CTX-M-9)-producing multiresistant strains of Salmonella enterica serotype Virchow in poultry and humans in France. J Clin Microbiol. 2004,42(12):5767-73.
205.Miles TD, McLaughlin W, Brown PD.Antimicrobial resistance of Escherichia coli isolates from broiler chickens and humans. BMC Vet Res.2006,6;2:7.
206.Sidjabat HE, Townsend KM, Hanson ND, et al. Identification of bla(CMY-7) and associated plasmid-mediated resistance genes in multidrug-resistant Escherichia coli isolated from dogs at a veterinary teaching hospital in Australia. J Antimicrob Chemother.2006,57(5):840-8.
207.盛祖嘉主编,微生物遗传学(第二版),北京,科学出版社。
208.包幼迪,细菌的结合转移试验,福建医学院学报增刊,1984；P100-102
209.张莉平,田兆菊,张西雷等,鸡致病性大肠杆菌的质粒DNA指纹图谱分析,山东农业大学学报(自然科学版),2007,38(4)：524-528
210.黄加权,高美英.大肠杆菌耐药现状与耐药质粒分析.中华传染病杂志,1996,14(2)：70-73.
211.江文正,韩文瑜,王世若.猪致病性大肠杆菌的质粒指纹图谱分析[J].中国兽医学报,1998,18(9)：475-478.
212.陆善勇,李康然.鸡源性大肠杆菌质粒指纹图谱及某些生物学特性的研究[J].广西农业大学学报,1993,12(9)：79-8
213.刘书亮,王红宁,陶勇,等.四川省规模化猪场大肠杆菌质粒DNA分析.西南农业学报.2000.13：69-73.
214.赵静,杨汉春.猪源大肠杆菌耐药性质粒的监测研究.黑龙江畜牧兽医.2000.1：6-9.
215.郑鑫,刘清河,刘晓华,王锡香.利用质粒指纹图谱法对大肠杆菌耐药质粒遗传特性的研究.吉林农业大学学报.2003.25(1)：97-101
216.郑巧敏,张秀霞,朱涛等,大肠埃希菌耐药性水平传播实验研究,中国微生态 学学报,2008,2(20)43-42。
217.陈琳,刘建华,陈杖榴等,rmtB阳性猪大肠杆菌及其接合子中Ⅰ类整合子研究,畜牧兽医学报,2010,41(12)：1576-1583