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31.
32.
当前兽医工作进展情况 1兽医管理体制改革深入推进(1)中央级兽医机构改革完成2004年7月14日,农业部成立兽医局,并设立国家首席兽医师(官),组建了中国动物疫病预防控制中心、中国动物卫生与流行病学中心以及北京、上海、兰州、哈尔滨四个分中心,在中国兽医药品监察所设立农业部兽药评审中心。  相似文献   
33.
高素质的青年编辑人才是科技期刊发展的关键力量,其中创新素质起着举足轻重的作用。青年编辑在成长过程中,应该以正确理解科技期刊中的创新性和科技期刊编辑的刨新素质为前提,不断提高人文修养、注重知识的广度和深度、加强自身专业修养、加强主观能动性,从而达到提高创新素质的目的。  相似文献   
34.
Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus within the family Flaviviridae. NS3 is one of the immunodominance regions of the BVDV viral proteins. To identify the potential B-cell linear antigenic epitopes within BVDV NS3 region, serial overlapping truncations covering the whole region were expressed and purified, and screened by multistep of Western-blot. We found (1VCKKITEHERCHVNI15), (20AFFGVMPRGTTPRAPVR36), (46RRGLETGWAYTHQGGI61), (281EGDMATGITYASYGYFC297), (426YSGEDPANLRVVTSQSPYVVVATNAIESGV455) and (481FIVTGLKRMAVTVGEQA497) can be recognized by the BVDV infected bovine serum. These proteins have been confirmed by indirect enzyme-linked immunosorbent assay (I-ELISA). The results of this study might open new perspectives on the structure and antibody–antigen reaction of the non-structural proteins and may aid in the clinical application as well.  相似文献   
35.
Since the emergence of the 2009 pandemic (H1N1) virus (2009/H1N1) in April 2009, cases of transmission from humans to pigs have been reported frequently. In our previous studies, four 2009/H1N1 variants were isolated from pigs. To better understand the phenotypic differences of the pig isolates compared with the human isolate, in this study mice were inoculated intranasally with different 2009/H1N1 viruses, and monitored for morbidity, mortality, and viral replication, cytokine production and pathological changes in the lungs. The results show that all isolates show effective replication in lungs, but varying in their ability to cause morbidity. In particular, the strains of A/swine/Nanchang/3/2010 (H1N1) and A/swine/Nanchang/F9/2010 (H1N1) show the greatest virulence with a persisting replication in lungs and high lethality for mice, compared with the human isolate A/Liaoning /14/2009 (H1N1), which shows low virulence in mice. Furthermore, the lethal strains could induce more severe lung pathological changes and higher production of cytokines than that of other strains at an early stage. Amino acid sequence analysis illustrates prominent differences in viral surface glycoproteins and polymerase subunits between pig isolates and human strains that might correlate with their phenotypic differences. These studies demonstrate that the 2009/H1N1 pig isolates exhibit heterogeneous infectivity and pathogencity in mice, and some strains possess an enhanced pathogenicity compared with the human isolate.  相似文献   
36.
用聚合酶链反应检测鸭瘟病毒的研究   总被引:19,自引:0,他引:19  
根据已发表的鸭瘟病毒基因序列 ,设计并合成了一对引物 ,其扩增跨幅为 60 2 bp。用这对引物对 6株鸭瘟病毒 DNA进行扩增 ,均获得了与设计大小相符的明亮条带 ,为阳性 ,而对其它 6株禽病病原体基因扩增不出任何条带 ,为阴性。敏感试验表明可检测到 1 0 0 fg的鸭瘟病毒 DNA模板  相似文献   
37.
H9N2亚型禽流感病毒在MDCK细胞中增殖最佳条件研究   总被引:1,自引:0,他引:1  
为了探讨H9N2亚型禽流感病毒在MDCK细胞中增殖的最佳条件,将不同毒株、不同接种量的H9N2亚型禽流感病毒接种MDCK细胞单层,接毒后直接加入或吸附lh后加入含有10 μg/mL胰蛋白酶的DMEM维持液,每隔24 h观察细胞病变,并测定细胞上清液中HA滴度.结果表明,分离株HN04在MDCK细胞中增殖能力较其他2株强...  相似文献   
38.
The therapeutic value of antibiotics depends on the susceptibility of the infecting microorganism and the pharmacological profile of the drugs. To assess the value of an antibiotic combination of polymyxin B and miconazole this study examined the in vitro synergistic potential of the two drugs on Gram-negative and Gram-positive bacteria and yeast. Antifungal and antibacterial activity was tested by minimum inhibitory concentration (MIC) of broth macrodilution and urea broth microdilution, by fluorescence microscopy and flow cytometry. Synergism was calculated using the fractional inhibitory concentration index (FICi). With Staphylococcus intermedius as target we found up to an eightfold reduction of the individual MICs when both drugs were combined. However, the FICi was 0.63 suggesting no real interaction between the two drugs. With Escherichia coli, Pseudomonas aeruginosa, and Malassezia pachydermatis as targets the antimicrobial drug combination reduced the MICs of polymyxin B and miconazole from fourfold to hundredfold resulting in FICi between 0.06 and 0.5 which defines a synergistic action. Thus, if polymyxin B and miconazole are combined their effect is greater than the sum of the effects observed with polymyxin B and miconazole independently, revealing bactericidal and fungicidal synergism. Our results indicate a strong therapeutic value for the combination of these antimicrobial agents against Gram-negative bacteria and yeast and a weaker value against Gram positive bacteria for clinical situations where these pathogens are involved.  相似文献   
39.
消毒药对于预防畜禽传染病的发生和蔓延具有重要作用,但在使用时应注意人、畜安全。特别是带体消毒更需谨慎。  相似文献   
40.
Bovine coronavirus (BCoV) is one of the main causes of neonatal calf diarrhoea. Several diagnostic assays have been employed to detect the presence of the virus in stool samples from calves. Despite this, the frequency of BCoV infection among Brazilian and even South American cattle herds has yet to be well characterised. This study describes the occurrence of BCoV infection among calves from dairy and beef herds in four Brazilian states. A total of 282 stool samples from 1 to 60-day-old calves were evaluated for the presence of BCoV by a semi-nested (SN) PCR assay. The animals were from herds (n = 23) located in three geographical regions in Brazil (south, southeast, and center-west). The specific BCoV amplicon was detected in 15.6% (44/282) of the faecal specimens examined, of which 95.4% (42/44) were from diarrhoeic and 4.6% (2/44) from asymptomatic calves. The specificity of the SN-PCR amplicons was evaluated by restriction fragment length polymorphism (RFLP) analysis. The results show that the BCoV is widespread, mainly among calves from 16 to 30-days-old (p = 0.0023), and verify the association between BCoV infection and clinical signs of diarrhoea (p = 0.005). These findings emphasise the importance of this virus in enteric infections of Brazilian cattle herds.  相似文献   
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