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991.
根据GenBank中美洲型猪繁殖与呼吸综合征病毒(PRRSV)的ORF6基因序列,设计合成一对特异性引物,应用RT-PCR方法扩增出PRRSV的ORF6基因(M基因)。将所扩增片段克隆入原核表达载体pET-32a(+),pET-ORF6重组质粒转化DH5a宿主菌后,经双酶切、PCR鉴定后挑选阳性克隆测序鉴定并对插入的ORF6基因序列进行分析。结果表明,ORF6基因的原核表达载体构建成功。ORF6基因推导的氨基酸与美洲型相应基因的同源性为96.0%~100%,与LV株的同源性为79.9%,系统进化树表明该PRRSV属于美洲型。将构建成功的重组质粒pET-ORF6转化BL21,诱导后经SDS-PAGE和Western-blot分析表明:克隆在HIS标签的膜基质蛋白基因与HIS获得了高效表达,表达的融合蛋白HIS-M分子量约为39kDa,并且有免疫学反应活性。 相似文献
992.
993.
该试验选用鸡的人工授精种蛋940枚及自然交配种蛋960枚,做了鸡的人工授精与自然资本种蛋孵化试验,结果表明:鸡人工授精后6d内种蛋受精率平均为94.5%,7d后,受经极显著降低;人工授精后的种蛋受经及入孵种蛋孵化率均极显著高于自然交配组,两两者的受精种蛋孵化率无明显差异;另外,在试验过程中,还研究了种蛋贮存时间与化结果的关系,发现种蛋贮存期越短,孵化效果越好,贮存期最长不应超过7d。 相似文献
994.
A porcine interferon-gamma-inducible lysosomal thiol reductase (GILT) cDNA, designated pGILT, was cloned by RT-PCR and rapid amplification of cDNA ends (RACE) strategies. The full-length cDNA of pGILT consists of 1,062 bp with a 741 bp open reading frame, encoding 246 amino acids, with a putative molecular weight of 29.5 kDa. The deduced pGILT possesses the typical structural feature of mammalian GILT, including an active-site CXXC motif, a GILT signature sequence CQHGX(2)ECX(2)NX(4)C, and 10 conserved cysteines. The genomic DNA sequence of pGILT contains seven exons and six introns, which is similar to vertebrate GILT exon-intron organization. The result of real-time PCR showed that GILT is expressed in many tissues in the pig, including spleen, liver, lung, heart, intestine, blood and kidney. And the pGILT expression is obviously up-regulated in spleen and blood after induction with LPS. These results suggesting that pGILT is highly likely to play a role in the innate immune responses in porcine. It also provided the basis for investigations on the role of GILT in this important domestic species and an animal model for human diseases. 相似文献
995.
996.
997.
为建立一种快速、敏感、特异的猪弓形虫检测方法,根据弓形虫保守基因序列,设计一套特异性引物和FAM荧光素标记的MGB探针;通过对PCR反应体系和反应条件进行优化筛选,建立了猪弓形虫实时荧光定量PCR检测方法,并对此PCR检测方法进行了特异性、敏感性、重复性试验;利用所建立的方法对60份疑似弓形虫感染的临床样品进行了检测。结果显示:建立的猪弓形虫实时荧光定量PCR检测方法在101~107拷贝/μL模板范围内有很好的线性关系;对弓形虫重组阳性质粒出现阳性扩增信号,但对阴性对照的水和其他7种病原对照未扩增出特异性曲线;最低检测模板浓度为10拷贝/μL;自60份疑似猪弓形虫感染样品中检出32份阳性,并且和克隆测序结果一致。结果表明,本研究建立的猪弓形虫实时荧光定量PCR检测方法可用于猪弓形虫的快速检测,从而为猪弓形虫病的诊断提供了特异、敏感、高通量的方法。 相似文献
998.
999.
Zhang Q Wang Z Yuan Y Xue Z Zhai G Zuo W Zhu S Zhu G Xu X 《Veterinary immunology and immunopathology》2011,141(1-2):116-123
Avian influenza viruses (AIV) of the H9 subtype cause serious health problems in chickens, resulting in great economic losses to the poultry industry worldwide. The killed vaccine (KV) against H9 subtype AIV has been widely used in China since 1998 but has been linked with side effects in chickens and only partial protection. A few studies have demonstrated the immunostimulatory effects of the hemagglutinating virus of Japan envelope (HVJ-E) in cancer therapy. In this study, the adjuvant efficacy and the protective effects of HVJ-E, in combination with H9N2 AI KV against AIV were evaluated. The maturation of murine dendritic cells treated by HVJ-E was verified by FACS in the current experiment, then the antibody hemagglutination inhibition (HI) titers and cytokines and the post-challenge virological profiles (oropharyngeal and cloacal virus shedding) were investigated to define the immune responses in chickens. Our findings indicate that HVJ-E could induce dendritic cell (DC) maturation in mice. Injection of HVJ-E in chickens resulted in raised levels of IFN-β and IFN-γ being present in sera suggesting a stimulatory effect in these animals. The antibody responses to AIV of chickens inoculated with HVJ-E adjuvanted killed H9-AIV were higher than those of chickens inoculated with oil adjuvanted H9-HIV. Furthermore, although inoculation of either HVJ-E or oil adjuvanted AIV reduced virus shedding following challenge, compared to controls, HVJ-E adjuvanted AIV was more effective in reducing shedding than oil adjuvant. 相似文献
1000.
Basit Zeshan Muhammad Hassan MushtaqXinglong Wang Wenliang LiPing Jiang 《Veterinary microbiology》2011
Infectious bronchitis virus (IBV) causes tremendous economic losses associated with production inefficiencies and mortality in poultry industry worldwide. In the present report, the recombinant adenoviruses expressing chicken granulocyte-macrophage colony stimulating factor (GM-CSF) and S1 gene of nephropathogenic IBV were constructed and characterized. Then, the immunological efficacy and protection against homologous IBV challenge were assessed in specific pathogen free (SPF) chickens. The results showed that the chickens vaccinated in ovo with rAd-S1, rAd-GM-S1 (GM-CSF fused with S1 using glycine linkers) and rAd-GM-CSF plus rAd-S1 (co-administered) developed specific anti-IBV HI antibodies. Moreover, the fusion of the GM-CSF markedly increased spleen cell proliferation and IFN-γ production while mild increased in IL-4 production, which demonstrated the enhancement of cell-mediated immune responses. Following challenge with IBV, the chickens in the group vaccinated with rAd-S1 fused or co-administered with GM-CSF had fewer nephropathic lesions and showed 100% protection as compared to that of rAd-S1 alone which showed 70% protection. It indicated that the single dose in ovo vaccination of the GM-CSF fused or co-administered with S1 of IBV could enhance significantly the humoral, cellular immune responses and provide complete protection against nephropathogenic IBV challenge. This finding may provide basic information for effective in ovo vaccines design against IBV. 相似文献