首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 30 毫秒
1.
We summarize antimicrobial resistance surveillance data in human and chicken isolates of Campylobacter. Isolates were from a sentinel county study from 1989 through 1990 and from nine state health departments participating in National Antimicrobial Resistance Monitoring System for enteric bacteria (NARMS) from 1997 through 2001. None of the 297 C. jejuni or C. coli isolates tested from 1989 through 1990 was ciprofloxacin-resistant. From 1997 through 2001, a total of 1,553 human Campylobacter isolates were characterized: 1,471 (95%) were C. jejuni, 63 (4%) were C. coli, and 19 (1%) were other Campylobacter species. The prevalence of ciprofloxacin-resistant Campylobacter was 13% (28 of 217) in 1997 and 19% (75 of 384) in 2001; erythromycin resistance was 2% (4 of 217) in 1997 and 2% (8 of 384) in 2001. Ciprofloxacin-resistant Campylobacter was isolated from 10% of 180 chicken products purchased from grocery stores in three states in 1999. Ciprofloxacin resistance has emerged among Campylobacter since 1990 and has increased in prevalence since 1997.  相似文献   

2.
The antimicrobial resistance profiles of Campylobacter isolates recovered from a range of retail food samples (n=374) and humans (n=314) to eight antimicrobial compounds were investigated. High levels of resistance in food C. jejuni isolates were observed for ceftiofur (58%), ampicillin (25%) and nalidixic acid (17%) with lower levels observed for streptomycin (7.9%) and chloramphenicol (8.3%). A total of 80% of human C. jejuni isolates were resistant to ceftiofur, while 17% showed resistance to ampicillin and nalidixic acid, 8.6% to streptomycin and 4.1% to chloramphenicol. Resistance to clinically relevant antimicrobials such as erythromycin, ciprofloxacin and tetracycline was 6.7, 12, and 15% respectively for all food isolates and was similar to corresponding resistance prevalences observed for human isolates, where 6.4, 12 and 13% respectively were found to be resistant. Comparisons of C. jejuni isolates in each location showed a high degree of similarity although some regional variations did exist. Comparison of total C. jejuni and C. coli populations showed minor differences, with C. jejuni isolates more resistant to ampicillin and ceftiofur. Multidrug resistance patterns showed some profiles common to human and clinical isolates.  相似文献   

3.
The purpose of this study was to analyze and compare antimicrobial resistance in Campylobacter spp. isolated from pork and poultry carcasses, and pork and poultry meat (at slaughterhouse level, during meat cutting, and at retail) in Belgium, using available surveillance data over the period 2004-2009. The susceptibilities of 1724 Campylobacter isolates for ampicillin, ciprofloxacin, nalidixic acid, tetracycline, erythromycin, and gentamicin were tested by E-test. Gentamicin resistance was low (near 0%) until 2007, with an increase to over 20% by 2009 for all species-matrix combinations. Resistance to tetracycline fluctuated around the same level during the entire study period and was significantly higher (p-value of <0.05) in C. coli than in C. jejuni. Erythromycin resistance was low and showed a slight decrease between 2004 and 2007, but increased from 2007 until 2009. Fluoroquinolone and ampicillin resistance was significantly higher in isolates derived from poultry, compared to pork-related isolates. This correlates with the higher use of these antimicrobials in poultry husbandry. A total of 25% of C. coli isolates from poultry showed the most apparent multiresistance (resistance to four or more antimicrobials). Approximately 1% of the poultry-derived isolates (both C. coli and C. jejuni) showed resistance to all tested antimicrobials, while none was found in pork products.  相似文献   

4.
Campylobacter species are one of the leading causes of foodborne disease in the United States. Campylobacter jejuni and Campylobacter coli are the two main species that are of concern to human health, and they cause approximately 95% of human infections. The number of studies investigating Campylobacter in chicken livers and gizzards is very limited in the literature. The objective of this study was to determine the prevalence of Campylobacter jejuni and Campylobacter coli in retail chicken livers and gizzards purchased from grocery stores in the Tulsa, Oklahoma, area and to further characterize the isolates obtained through antimicrobial susceptibility testing. A total of 202 retail chilled chicken livers and gizzards (159 livers and 43 gizzards) were purchased on a weekly basis from several grocery stores. The overall prevalence of Campylobacter in chicken livers and gizzards was 136/202 (67%), where 69/202 (34%) of the samples were contaminated with Campylobacter jejuni and 66/202 (33%) with Campylobacter coli. While the prevalence of Campylobacter in chicken livers was 77%, its prevalence in chicken gizzards was lower at 33%. The prevalence of Campylobacter jejuni was slightly higher in chicken livers (36%) than gizzards (26%), while the prevalence of Campylobacter coli was significantly higher in the chicken livers (40%) than chicken gizzards (7%). The prevalence of resistance among C. jejuni and C. coli isolates recovered against 16 antimicrobials were as follows: amoxicillin (98%, 99%), ampicillin (32%, 55%), azithromycin (10%, 25%), cephalothin (92%, 99%), chloramphenicol (4%, 12%), ciprofloxacin (58%, 48%), clindamycin (5%, 19%), doxycycline (39%, 66%), erythromycin (6%, 32%), gentamicin (9%, 43%), kanamycin (11%, 43%), nalidixic acid (50%, 43%), oxytetracycline (99%, 100%), streptomycin (3%, 18%), tetracycline (37%, 60%), and tilmicosin (9%, 16%). Multidrug resistance was higher among Campylobacter coli than Campylobacter jejuni isolates.  相似文献   

5.
Intestinal thermophilic Campylobacter species produce stable patterns when subjected to bacterial restriction endonuclease DNA analysis (BRENDA); this technique is therefore of considerable value in epidemiological studies. BRENDA was used to examine thermophilic Campylobacter species from humans, wild and domestic animals. One hundred and ninety-four (61%) of 316 isolates of Campylobacter jejuni from humans had BRENDA patterns which could be matched to those of animal isolates. Poultry appear to be a major source of infection for C. jejuni in humans with nearly half (49.7%) of the human isolates giving patterns which were indistinguishable from those isolated from poultry. A total of 60 BRENDA types were identified from 316 human isolates and 11 of these had the same pattern as those isolated from poultry. One of the three Campylobacter coli BRENDA types recovered from poultry was indistinguishable from a human isolate type. Pigs appear to be only a minor source of C. coli infection for humans in New Zealand. Rats were found to be infected with strains of C. jejuni with BRENDA patterns indistinguishable from those infecting humans, poultry and a horse. None of the 102 isolates of Campylobacter species from wild birds gave BRENDA patterns similar to those of isolates from humans.  相似文献   

6.
This study investigated fluoroquinolone, macrolide resistances and serotype distributions among Campylobacter jejuni and Campylobacter coli isolated from children in Bangkok and rural settings during 1991-2000. Phenotypic identification, serotyping, and susceptibility testing were performed by standard microbiological procedures. The predominant serotypes of C. jejuni were Lior 36, 2 and 4 and of C. coli were Lior 8, 29 and 55. Resistance to nalidixic acid increased significantly during 1991-2000 and the frequency of isolates resistant to both nalidixic acid and ciprofloxacin in Bangkok was significantly greater than in rural settings. In 1996-2000, a significant trend was observed in C. jejuni isolates resistant to ciprofloxacin from Bangkok but not for macrolide resistance from both settings. In summary, fluoroquinolone resistance among C. jejuni and C. coli isolates became widespread in both Bangkok and rural settings in Thailand in the 1990s while widespread resistance to macrolides was undetected.  相似文献   

7.
From February 1999 to February 2000, 1,250 individual broiler chickens representing 125 broiler flocks originating from 62 broiler farms in Denmark were screened for campylobacter carriage. Every month, 10 flocks were tested for campylobacter carriage. The swabs were tested individually and as a pooled sample representing the flocks. Campylobacter spp. carriage was detected from 512 (40.9%) broiler chickens originating from 63 (50.4%) positive flocks. Campylobacter carriage by both individual chickens and flocks showed seasonal variation. Campylobacter jejuni was the dominant species (95.5%). Campylobacter isolates were typed using Penner heat-stable serotyping and flaA-typing methods. Data of campylobacter carriage by individual chickens and data generated by the use of different typing methods contributed to a better understanding of the dynamics of campylobacter infection within the broiler flocks. C. jejuni Penner heat-stable serotype HS2, flaA-type 1 was the most common type found in Danish broiler chickens.  相似文献   

8.
Sixty-six broiler flocks were sampled to determine the presence of Campylobacter spp. at slaughter in 1998. Thirty flocks (45%) tested positive and C. jejuni was identified in all isolates. Combined pulsed-field gel electrophoresis/amplified fragment length polymorphism (PFGE/AFLP) subtyping of 177 isolates from 24 positive flocks revealed 62 subtypes; 16 flocks harboured more than one subtype. When subtyping 101 clinical C. jejuni isolates collected in the same time period and area, 60 PFGE/AFLP types were identified. Comparison of subtypes from poultry and human isolates revealed three shared PFGE/AFLP types, which were present in 11 human isolates. Fifty per cent of all poultry isolates and 39% of all human isolates were resistant to ciprofloxacin. The present study confirms the increase in ciprofloxacin resistance in both human and poultry C. jejuni isolates in Austria, as observed in several countries worldwide. A small number of human isolates shared PFGE/AFLP types with poultry isolates, however, further studies should also focus on the identification of other sources of C. jejuni infection in humans.  相似文献   

9.
The subtypes of Campylobacter isolates from human infections in two Danish counties were compared to isolates from retail food samples and faecal samples from chickens, pigs and cattle. During a 1-year period, 1285 Campylobacter isolates from these sources were typed by two methods: 'Penner' heat-stable serotyping and automated ribotyping (RiboPrinting). C. jejuni was the dominating species, but C. coli was more prevalent among food and chicken isolates (16%) compared to human isolates (4%). In total, 356 different combined sero-ribotypes (subtypes) were found. A large subtype overlap was seen between human isolates and isolates from food (66%), chickens (59%) and cattle (83%). This was verified by PFGE typing of 212 isolates representing selected subtypes. All frequent (n>3) subtypes found in food were also present in humans. Sixty-one per cent of the isolates from domestically acquired infections had subtypes that were also found in food as opposed to 31% of travel-associated infections. The results showed differences in the various Campylobacter populations, e.g. the Danish population as reflected in the domestically acquired infections and the Danish-produced food was more uniform than the isolates originating from outside the country. The study shows that most C. jejuni subtypes found in poultry food samples, broiler chickens, and cattle were represented in the domestically acquired cases, indicating that C. jejuni from these reservoirs are likely sources of human infections in Denmark.  相似文献   

10.
During the period January 1998-December 2001, all Danish broiler flocks were monitored bacteriologically for thermophilic campylobacters and isolates were stored at -80 degrees C. Six neighbouring broiler farms in a small community were selected for detailed examination of all Campylobacter jejuni isolated (n = 180) from these farms during 1998-2000 using Penner serotyping and pulsed-field gel electrophoresis (PFGE). The area and the farms were selected according to their prevalence of campylobacter so that both farms with low and high frequencies of campylobacter positive flocks were included in the study. The frequency of campylobacter positive flocks on the six farms ranged from 24.5 to 72.7%. One hundred and eighty of the isolates were C. jejuni (included in this study), 14 isolates were C. coli whereas 7 isolates belonged to other species but were not further identified. By serotyping of all C. jejuni 56 isolates (31.5%) were assigned to the 4-complex, 32 isolates (18.0%) to serotype 2, 12 isolates (6.7%) to serotype 11, and 11 isolates (6.2%) were assigned to serotype 12. In three farms, 4-complex was the most prevalent serotype, in one farm it was the second most frequently isolated serotype, while serotypes 2 and 1,44, respectively, were the most frequently isolated from the two remaining farms. This serotype distribution differed from the overall country-wide distribution where serotypes 2 and 1,44 are the most prevalent. All serotype 4-complex isolates from the six selected farms were compared by PFGE to serotype 4-complex isolates from the rest of the country. The results showed that there was a high level of diversity among isolates from the whole country, whereas isolates from the six farms were very homogeneous and only displayed one or a few different PFGE patterns on each farm. It is suggested that certain campylobacter clones persist in a confined geographical area, probably at the farm, and that the broiler houses may be repeatedly infected with a few C. jejuni clones during succeeding broiler flocks. New clones may be introduced, however, the sources and vehicles are yet unknown.  相似文献   

11.
The objective of the present study was to compare polymerase chain reaction (PCR) identification with ribotype results and to use pulsed field electrophoresis (PFGE) to correlate genotypic patterns with antibiotic resistance of Campylobacter isolated from lactating dairy cows in the United States. Thirty isolates were studied. Twenty-seven of the isolates were identified by PCR as Campylobacter jejuni and three were identified as Campylobacter coli. Genotypic patterns of 15 isolates were determined by PFGE, and although isolates originated from geographically separated regions of the United States, some were genotypically identical. In contrast to their genetic similarity, antibiotic sensitivity patterns differed within some genotypes. Under the conditions of our study, we concluded that ribotyping is not as discriminatory as PCR for speciation, and that a phenotypic trait such as antimicrobial resistance cannot always be predicted within the same genotype.  相似文献   

12.
We conducted a study to compare the prevalence and antimicrobial resistance profile of Campylobacter isolated from 34 farm-slaughter pair cohorts of pigs raised in conventional and antimicrobial-free (ABF) production systems. Isolates originated from four different states of two geographic regions (region 1--Ohio and Michigan; region 2--Wisconsin and Iowa). A total of 838 fecal and 1173 carcass samples were examined. Campylobacter isolates were speciated using multiplex polymerase chain reaction targeting ceuE and hipO genes. The minimum inhibitory concentration was determined using agar dilution to a panel of six antimicrobials: chloramphenicol, erythromycin, gentamicin, ciprofloxacin, nalidixic acid, and tetracycline. Campylobacter spp. was isolated from 472 of 838 pigs (56.3%). Campylobacter prevalence did not vary significantly based on production system (conventional [58.9%] and ABF [53.7%], odds ratio [OR] 1.4, 95% confidence interval [CI] 0.8-2.6, p?=?0.24) or geographic region (region 1 [54.1%] and region 2 [58.2%], OR 1.02, 95% CI 0.6-1.9, p?=?0.92). At slaughter plant, Campylobacter prevalence varied based on processing stages (19.4% at pre-evisceration, 25.3% at postevisceration, and 3.2% at postchill). Resistance was common to tetracycline (64.5%), erythromycin (47.9%), and nalidixic acid (23.5%). Campylobacter isolates from conventional production systems were more likely to be erythromycin resistant than from ABF (OR 3.2, 95% CI 1.4-7.2, p?=?0.01). The proportion of ciprofloxacin-resistant Campylobacter coli isolates were 3.7% and 1.2% from ABF and conventional production systems, respectively. Thirty-seven out of 1257 C. coli (2.9%) were resistant to both erythromycin and ciprofloxacin, drugs of choice for treatment of invasive human campylobacteriosis. The finding of ciprofloxacin resistance, particularly from ABF herds, has significant implications on the potential role of risk factors other than mere antimicrobial use for production purposes.  相似文献   

13.
Campylobacteriosis in humans is primarily caused by handling or consuming contaminated poultry or their products. The aims of this study were to estimate the prevalence of Campylobacter spp. in domestic and imported poultry meat in Korea and to further characterize the obtained isolates. From 2004 to 2008, a total of 475 domestic and 867 imported raw poultry meat samples were examined for the presence of Campylobacter spp. Among 475 domestic poultry meat samples, Campylobacter jejuni and Campylobacter coli were isolated from 219 (46.1%) and 156 (32.8%), respectively. Relative prevalence of C. jejuni and C. coli was higher in meat from Brazil (39/78, 50.0% and 7/78, 8.9%) and France (32/96, 33.3% and 8/96, 8.3%), whereas lower in meat from Denmark (72/516, 14.0% and 12/516, 2.3%) and Thailand (5/39, 12.8% and 3/39, 7.6%). The resistance to ampicillin and tetracycline was highly prevalent in Campylobacter spp. from most countries investigated, whereas lower in meat from Denmark. On the other hand, the prevalence of erythromycin and gentamicin resistance was less than 10% in most countries. The resistance rate to nalidixic acid, ciprofloxacin, and enrofloxacin ranged from 11.9% to 87.5%. The use of fla-polymerase chain reaction–restriction fragment length polymorphism for epidemiological analysis found that some pattern types were considerably more frequent and distinct in meat from each country. In conclusion, we report the presence of high contamination in domestic and imported poultry meat in Korea and the antimicrobial and genetic diversity of Campylobacter spp. between each country.  相似文献   

14.
In order to determine the prevalence of campylobacter positive broiler flocks in Finland, every flock from all three major slaughterhouses was studied during the period from 1 May to 30 September 1999. Caecal samples were taken in the slaughterhouses from five birds per flock. A total of 1132 broiler flocks were tested and 33 (2.9%) of those were campylobacter positive. Thirty-one isolates were C. jejuni and two isolates were C. coli. Isolates were serotyped for heat-stable antigens (Penner) and genotyped with pulsed-field gel electrophoresis (PFGE). The most common serotypes were serotypes 6, 7, 12 and 4-complex. Together with SmaI and KpnI patterns there were 18 different PFGE genotypes. Simultaneous monitoring of chicken flocks and typing of the isolates produced data which can be used to study the epidemiology of campylobacters in chicken as well as their role in human infections.  相似文献   

15.
In this study comprising isolates from 2001 to 2003, resistance was considerably more widespread among Campylobacter jejuni from humans infected abroad than infected within Norway. The discrepancy was particularly notable for fluoroquinolone resistance (67.4% vs. 6.5%). This is probably a reflection of a low resistance prevalence in Norwegian broiler isolates (1.2% fluoroquinolone resistant).  相似文献   

16.
While Campylobacter, Salmonella, and Shigella remain major contributors to acute enteric infections, few studies on these pathogens have been conducted in Egypt. From January 1986 to December 1993, 869 Salmonella, Shigella and Campylobacter strains were isolated from stool specimens from 6,278 patients, presenting to the Abbassia Fever Hospital, Cairo, Egypt, with acute enteric infections. Salmonella predominated, totalling 465 isolates, followed by Shigella with 258 isolates, and Campylobacter with 146 isolates. Of the Shigella isolates, 124 were Shigella flexneri, 49 were S. sonnei, 47 were S. dysenteriae (mainly serotype 1, 2, and 3), and 38 were S. boydii. Campylobacter spp. comprised 92 Campylobacter jejuni and 54 C. coli isolates. Isolation of Salmonella was highest during the months of February-March, June-July, and October-November, while that of Shigella was maximal from July to October. Isolation of Campylobacter increased during May-June and again during August-October. Although Salmonella was sensitive to amikacin, aztreonam, ceftriaxone, and nalidixic acid, it was, however, resistant to erythromycin, streptomycin, ampicillin, chloramphenicol, and tetracycline. Shigella (> 80%) was sensitive to amikacin, ceftriaxone, cephalothin, sulphamethoxazole-trimethoprim (except S. sonnei), aztreonam, and nalidixic acid. Resistance (> 50%) was noted only for ampicillin, chloramphenicol, and tetracycline. C. jejuni and C. coli were resistant to cephalothin, aztreonam, and streptomycin. Some of the above antibiotics were employed to characterize the Egyptian isolates, but did not have any clinical utility in the treatment of diarrhoea. Significant differences (p < 0.05) were observed in the resistance profiles of Shigella and Salmonella between late 1980s and early 1990s. The results suggest the use of fluoroquinolones or a third-generation cephalosporin as an empirical treatment of enteric diseases. However, alternative control strategies, including the aggressive development of broadly protective vaccines, may be more effective approaches to curbing morbidity and mortality due to acute enteric infections.  相似文献   

17.
Routine surveillance of infection in England and Wales detected 394 cases of campylobacter bacteraemia in 11 years. This represented an average incidence of 1.5 per 1000 intestinal campylobacter infections, with a range of 0.3/1000 in children aged 1-4 years to 5.9/1000 in patients aged 65 years or more. Definitive identification of 257 isolates showed that 89% were Campylobacter jejuni or C. coli; other species were C. fetus (8.6%), C. lari (0.8%), C. upsaliensis (0.8%), Helicobacter (Campylobacter) fennelliae (0.8%), and Helicobacter (Campylobacter) cinaedi (0.4%). Most (71%) of the C. jejuni/C. coli bacteraemias were in patients with acute enteritis. Of the patients with C. fetus bacteraemia only 27% had diarrhoea; they were older than patients with C. jejuni or C. coli bacteraemia (54.1 v. 45.9 years) and proportionally more of them were male (M:F ratio 2.7:1 v. 1.9:1); 41% had endovascular pathology or cellulitis. There was a higher proportion of C. jejuni serogroup O 4 (Penner) and O 18 strains among blood than faecal isolates, which suggests that they were unusually serum resistant and/or invasive.  相似文献   

18.
目的建立空肠弯曲菌、结肠弯曲菌多重聚合酶链反应(m-PCR)鉴定方法,并对菌株毒力相关基因cadF、virB11、flaA、cdtA、cdtB、cdtC的分布进行初步分析。方法利用m-PCR的方法对经过传统生物化学方法鉴定的65株弯曲菌进行鉴定,并通过空肠弯曲菌特异基因hipO、结肠弯曲菌glyA基因特异片段的PCR扩增对鉴定的结果进一步验证;利用特异引物PCR方法初步分析其毒力、毒素相关基因cadF、virB11、flaA、cdtA、cdtB和cdtC的分布。结果m-PCR扩增结果发现65株不同来源的弯曲菌,42株为空肠弯曲菌,23株为结肠弯曲菌。hipO、glyA基因PCR扩增结果与m-PCR扩增结果一致。16.9%菌株PCR鉴定结果与传统的生物化学鉴定结果不一致。100%(65/ 65)菌株cadF、flaA基因阳性,并且PCR扩增片段大小一致。virB的阳性率为10.8%(7/65),其中空肠弯曲菌阳性率11.9%(5/42),结肠弯曲菌阳性率为8.7%(2/23)。空肠弯曲菌、结肠弯曲菌cdtA的阳性率分别为100%(42/42)和78%(18/23);空肠弯曲菌cdtB扩增的的阳性率为97.6%(41/42)。而23株结肠弯曲菌扩增结果均为阴性;空肠弯曲菌、结肠弯曲菌cdtC的阳性率皆为100%,但PCR扩增产物大小不一致,空肠弯曲菌为555 bp,结肠弯曲菌约为465 bp。结论m-PCR的方法可以有效的对空肠弯曲菌和结肠弯曲菌进行属内分型。中国菌株细胞溶涨毒素基因簇cdt基因的特征与文献报道国外菌株存在差异。  相似文献   

19.
We integrated data on quinolone and macrolide susceptibility patterns with epidemiologic and typing data from Campylobacter jejuni and C. coli infections in two Danish counties. The mean duration of illness was longer for 86 patients with quinolone-resistant C. jejuni infections (median 13.2 days) than for 381 patients with quinolone-sensitive C. jejuni infections (median 10.3 days, p = 0.001). Foreign travel, eating fresh poultry other than chicken and turkey, and swimming were associated with increased risk for quinolone-resistant C. jejuni infection. Eating fresh chicken (of presumably Danish origin) was associated with a decreased risk. Typing data showed an association between strains from retail food products and broiler chickens and quinolone-sensitive domestically acquired C. jejuni infections. An association between treatment with a fluoroquinolone before stool-specimen collection and having a quinolone-resistant C. jejuni infection was not observed.  相似文献   

20.
This study was conducted to examine the in vitro activity of antimicrobials against Campylobacter spp. isolates from chicken and human sources and the genetic interrelation among them. During 2004-2008, a total of 173 Campylobacter spp. isolated from chicken meats (60 domestic and 62 imported chicken meats) and humans (n?=?51) were tested for susceptibility to nine antimicrobials. Of 173 isolates, 140 (80.9%) showed multidrug resistance (MDR) against three to eight antimicrobials. The most frequent pattern type was MDR to four antimicrobials: ciprofloxacin, nalidixic acid, ampicillin, and tetracycline. Over 52.6% (91/173) of the isolates tested were resistant to these four antibiotics simultaneously. Especially, two and five isolates originated from Korea and Brazil showed resistance against all antibiotics tested, except for florfenicol. Further, 95% (57/60) of the isolates originated from domestic chicken showed resistance to ciprofloxacin, the antimicrobial agent of choice for treatment of human campylobacteriosis. Genotypic characterization of all Campylobacter isolates performed by pulsed-field gel electrophoresis yielded 74 types among the 173 isolates. Isolates sharing the same or similar genetic clusters were detected in different countries at different times. The pulsed-field gel electrophoresis patterns of chicken-related isolates were closely related to those of isolates from humans with gastroenteritidis. The results of this study suggest that MDR Campylobacter spp. are widespread and that Campylobacter with similar genotypes are circulating both in humans and in chicken meat in Korea.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号