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981.
为建立一种有效的牛病毒性腹泻病病毒(Bovine viral diarrhea virus,BVDV)抗体检测方法,作者将BVDVNS3蛋白2个抗原表位的编码核酸序列进行串联,构建重组表达载体pET-30a-EXnN,并在原核表达系统中表达了重组蛋白。选取包含12个表位肽的重组蛋白(r-BVDV-EX6N)作为包被抗原建立NS3蛋白抗体间接ELISA方法。该方法的特异性和稳定性良好,与2种商品化试剂盒的符合率分别为96.05%和78.95%。试验结果表明建立的ELISA方法可用于BVDV NS3蛋白抗体的检测。  相似文献   
982.
动物消化道黏膜免疫的研究现状   总被引:1,自引:0,他引:1  
刘文倩  张杰  刘永生 《江西农业学报》2009,21(7):155-157,161
介绍了动物消化道黏膜免疫系统的组成,阐述了消化道黏膜免疫的免疫机理及影响因素的研究进展。  相似文献   
983.
文章从卵母细胞的来源、精子体外获能、卵母细胞体外成熟、体外受精和体外受精早期胚胎培养五个方面综述了牛卵母细胞体外受精和体外成熟技术的研究进展.同时指出了影响精子体外获能的因素、影响卵母细胞成熟培养的因素、体外受精存在的问题及解决办法等.并且对影响该技术的主要因素进行了系统分析.  相似文献   
984.
在前期工作的基础上,构建了pGEM—TE—ESAT6重组载体,转化至大肠杆菌BL21(DE3)感受态细胞中,经诱导表达得到了20kD左右大小的重组蛋白,SDS—PAGE/Western Blot显示该重组蛋白是上清表达。为重组ESAT-6抗原的应用奠定了基础。  相似文献   
985.
The aim of this study was to examine the distribution of microvessels in the theca and the expression of vascular endothelial growth factor (VEGF) in the theca and granulosa of cystic follicles. Paraffin sections of cystic follicles were stained with Bandeiraea simplicifolia-I (BS-I) to visualize the endothelial cells of microvessels. The other sections were immunostained with anti-VEGF antibody. The mRNA expression of VEGF in the theca interna of cystic and healthy follicle was determined by RT-PCR. In the theca interna, cystic follicles with granulosa cells had significantly greater microvessel number density (the number of microvessels per given field) and area (area occupied by microvessels per given area) than healthy follicles in various sizes (<3, 4–8, >9 mm). Loss of granulosa cells from cystic follicles resulted in a similar number density, but significantly smaller area of microvessels in the theca interna. There was no significant difference in the microvessel number density and area of the theca externa between the types of follicle. VEGF protein was expressed in the granulosa and theca interna of healthy and cystic follicles. These results demonstrate that cystic follicles have a highly developed vasculature network in the theca interna, especially in cystic follicles containing granulosa cells. It is also suggested that VEGF is highly expressed in the cystic follicle as well as healthy follicle, which may be associated with advanced vasculature and the accumulation of follicular fluid in cystic follicles.  相似文献   
986.
    
Heat stress induced by long periods of high ambient temperature decreases animal productivity, leading to heavy economic losses. This devastating situation for livestock production is even becoming worse under the present climate change scenario. Strategies focused to breed animals with better thermo-tolerance and climatic resilience are keenly sought these days to mitigate impacts of heat stress especially in high input livestock production systems. The 70-kDa heat shock proteins (HSP70) are a protein family known for its potential role in thermo-tolerance and widely considered as cellular thermometers. HSP70 function as molecular chaperons and have major roles in cellular thermotolerance, apoptosis, immune-modulation and heat stress. Expression of HSP70 is controlled by various factors such as, intracellular pH, cyclic adenosine monophosphate (cyclic AMP), protein kinase C and intracellular free calcium, etc. Over expression of HSP70 has been observed under oxidative stress leading to scavenging of mitochondrial reactive oxygen species and protection of pulmonary endothelial barrier against bacterial toxins. Polymorphisms in flanking and promoter regions in HSP70 gene have shown association with heat tolerance, weaning weight, milk production, fertility and disease susceptibility in livestock. This review provides insight into pivotal roles of HSP70 which make it an ideal candidate genetic marker for selection of animals with better climate resilience, immune response and superior performance.  相似文献   
987.
Background: Heifers not used as breeding stock are often implanted with steroids to increase growth efficiency thereby altering hormone profiles and potentially changing the environment in which ovarian follicles develop. Because bovine granulosa cell culture is a commonly used technique and often bovine ovaries are collected from abattoirs with no record of implant status, the objective of this study was to determine if the presence of an implant during bovine granulosa cell development impacts follicle stimulating hormone-regulated steroidogenic enzyme expression. Paired ovaries were collected from 16 feedlot heifers subjected to 1 of 3 treatments: non-implanted (n = 5), Revalor 200 for 28 d (n = 5), or Revalor 200 for 84 d (n = 6). Small follicle (1 to 5 mm) granulosa cells were isolated from each pair and incubated with phosphate buffered saline (n = 16) or 100 ng/mL follicle stimulating hormone (n = 16) for 24 h. Results: Granulosa cells of implanted heifers treated with follicle stimulating hormone produced medium concentrations of progesterone similar (P = 0.22) to non-implanted heifers, while medium estradiol concentrations were increased (P 〈 0.10) at 28 and 84 d compared to non-implanted heifers indicating efficacy of treatment. Additionally, real-time PCR analysis in response to follicle stimulating hormone treatment demonstrated a decrease in steroidogenic acute regulatory protein (P = 0.05) mRNA expression in heifers implanted for 84 d and an increase in P450 side chain cleavage mRNA in granulosa cells of heifers implanted for 28 (P 〈 0.10) or 84 d (P 〈 0.05) compared to non-implanted females. However, no difference in expression of 3-beta-hydroxysteroid dehydrogenase (P= 0.57) and aromatase (P = 0.23) were demonstrated in implanted or non-implanted heifers. Conclusions: These results indicate follicles which develop in the presence of high concentrations of androgenic and estrogenic steroids via an implant tend to demonstrate an alter  相似文献   
988.
用研制的猪流行性腹泻病毒(PED)灭活苗和猪两种腹泻病毒混合感染(TGE与PEDV)灭活苗分别进行了人工感染性免疫,主,被动免疫,交互免疫,免疫力产生时间,免疫期和野外免疫预防等对比试验,结果表明,2种疫苗除具有较好的免疫力外,它们之间既存在免疫的相关性,也各具有其特异性。  相似文献   
989.
将荧光引入免疫分析,使荧光免疫分析成为一种高灵敏的分析手段,具有操作简便、检测快速、准确度高和选择性好等优点,符合新的现场检测及监管的需求,近年在农残检测领域研究炙手可热。本文以荧光免疫分析为基础,系统综述了原理、常见的荧光标记物及近年来发展的几种较成熟的荧光免疫分析技术,并对其在农药残留检测上的应用进行了介绍,最后对该领域的研究前景进行了展望。  相似文献   
990.
牛病毒性腹泻病毒RT—PCR检测方法研究   总被引:1,自引:0,他引:1  
【目的】建立快速、简便、特异的检测牛病毒性腹泻病毒抗原的RT-PCR方法;【方法】根据已发表的牛病毒性腹泻病毒株(BVDV)5’端非编码区保守序列设计合成了两条引物,应用RT-PCR技术对两株BVDV标准株(OregonC24V and NADL)进行基因扩增,对扩增产物进行酶切鉴定。同时设猪瘟兔化弱毒疫苗株、轮状病毒株、MDBK细胞作对照;【结果】两株BVDV标准株均扩增出了长度为325bp的片段,扩增产物经酶切后形成长度为111bp和214bp两条片段,而对猪瘟兔化弱毒疫苗株、轮状病毒株、MDBK正常细胞扩增均为阴性,与预期结果一致。【结论】PCR检测方法可以快速准确地对牛病毒性腹泻-黏膜病作出诊断。该方法的敏感性可高达10-1TCID50。  相似文献   
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