一种获得重组传染性法氏囊病病毒的新方法

采用 RT- PCR技术 ,从传染性法氏囊病病毒 (IBDV)细胞适应株 GZ911中扩增了 A片段的 2个片段 GA5和 GA3,从中国分离的 IBDV超强毒株 L X中扩增了 B片段的 2个片段 L B5和 L B3。将 GA5和 GA3克隆到质粒p Bss K的 Eco R / Kpn 位点 ,将 L B5和 L B3克隆到 p Bss K的 Eco R / Xba 位点 ,获得携带 GZ911完整 A片段基因的质粒 GA- p Bss K和携带 L X完整 B片段基因的质粒 L B- p Bss K。然后将 GZ911的 A片段 c DNA和 L X的 B片段c DNA分别插入带有巨细胞病毒立即早期加强子 /启动子的质粒 p AL TER- MAX中 ,获得重组质粒 GA- p AL TER和L B- p AL TER。用 GA- p AL TER和 L B- p AL TER共转染鸡胚成纤维细胞 (CEF) ,获得具有感染活性的重组 IBDV,命名为 r IBDV- GZ L X。该方法的建立为在体外对 IBDV的基因组进行遗传操作 ,进而彻底了解 IBDV基因的结构与功能的关系打下了基础。     

鸡,鸭体内传染性法氏囊病病毒的分离及理化性质比较

从疑似传染性法氏囊病（ＩＢＤ）病鸡及同群饲养的鸭体内各分离到１株病毒，用传染性法氏囊病病毒（ＩＢＤＶ）单克隆抗体夹心ＥＬＩＳＡ试验证明两病毒均为ＩＢＤＶ，病毒血清型为Ⅰ型。病毒可致死鸡胚，适应于鸡胚成纤维细胞并产生细胞病变（ＣＰＥ）。理化性质比较表明，两病毒为同源ＩＢＤＶ。研究表明，鸭可成为ＩＢＤＶ的携带者或传染源。     

Simulation analysis of the effect of herd immunity and age structure on infection of a cattle herd with bluetongue viruses in Queensland, Australia

A state-transition model based on Leslie matrix formulation was used to investigate the effects of herd immunity and age structure on the infection of a simulated cattle herd with bluetongue viruses under Australian climatic conditions. Increasing duration of immunity decreased the prevalence of infection. A duration of immunity of 33 months was consistent with prevalence estimates made from previous serological studies of bluetongue virus. Herd prevalence displayed slowly dampening cyclical variation over time (most pronounced when a short duration of immunity was simulated). Increasing calving and mortality risk rates in the simulated herd increased prevalence, whereas increasing age at first calving decreased prevalence. Manipulation of calving rates had the greatest effect on the predicted prevalence of infection in the herd. Simulation of a number of herd-management scenarios suggested that management systems in which cattle are bred early and where high calving rates are achieved are likely to contribute to high levels of infection with bluetongue viruses. Results confirm the importance of management factors in influencing the prevalence of infectious diseases in animal populations.     

猫泛白细胞减少症病毒的分离与鉴定

应用猫肾传代细胞(FK),采用同步接毒的方法,从8份狮、虎、豹病料中分得6株病毒,经与标准病毒作交叉免疫电镜等系统鉴定,证明与猫泛白细胞减少症病毒的特性基本相符,从而首次证实在我国动物园狮、虎、豹等猫科动物中存在猫泛白细胞减少症。     

The fat content of milk from dairy cattle infected with bovine leukosis virus

Two groups of cows infected with the bovine leukosis virus (BLV) were kept on two different diets and the fat content of their milk was assayed. The results were compared with those obtained from two comparable groups of BLV-free cows. The cows in each group were of similar ages, those in the groups on the poorer diet being 1–4 months post partum, while those on the richer diet were 5–7 months post partum. The mean percentage of fat in the milk from uninfected cows on the poorer diet was 2.94 while that from the similar infected cattle was 3.06. Uninfected cows on the richer diet produced milk containing 3.39% fat, while those that were infected produced milk containing 3.30% fat. No statistical differences in milk fat production were observed between the BLV seropositive and seronegative cows.     

欧鳗(Anguilla anguilla)“狂游症”病调查报告

本文在国内首次较系统报告了欧鳗“狂游症”病的流行病学、病理组织学、诊断和防治方法，同时在国内外首次报告了侵袭欧鳗脑部的病毒是该病的致病原，这对今后深入研究起到很大的作用。     

蛋白结晶技术在病毒学中的应用

病毒及其亚单位蛋白的三维结构 (3 D)解析是认识病毒蛋白功能的有力手段。对病毒结构的认识正经历着病毒粒子电镜结构、纳米水平的精细结构及病毒组成蛋白原子水平 3 D结构的变化。晶体的 X射线衍射技术可在原子水平上认识病毒蛋白的结构。这为从结构生物学的角度认识病毒复制、病毒粒子的装配、病毒的致病与免疫机理及抗病毒药物设计提供了技术平台     

酵母双杂交系统在植物病毒学上的应用

酵母双杂交系统是研究蛋白质间相互作用的一种有效方法,具有操作简便、灵敏度高的特点.该技术主要在植物病毒学的如下领域得到应用:(1)病毒粒体的分子结构和装配;(2)病毒的核酸复制以及基因表达调控;(3)病毒介体传播的分子机制;(4)病毒运动模式;(5)病毒致病机制;(6)病毒编码蛋白的联系图谱.     

间作对番茄黄化卷叶病毒病发生的影响

番茄黄化卷叶病毒的流行危害引起番茄产量大幅度下降，番茄间作其它作物，可减轻媒介昆虫传毒，是综合防治番茄黄化卷叶病毒的有效方法之一。番茄间作黄瓜、玉米、菜用大豆、黄秋葵、红薯后对发病情况及白粉虱虫口密度的影响试验结果表明，定植58d后，病害发生达高峰期；白粉虱成虫迁飞高峰在1月份，1月中旬至2月中旬白粉虱幼虫虫口密度最大；定植后37、47、58、78d，不同间作作物上白粉虱幼虫虫口密度有显著或极显著差异；黄瓜、菜用大豆是白粉虱偏爱的寄主植物；番茄间作菜用大豆、玉米、红薯、黄瓜对番茄黄化卷叶病毒有一定防效。     

提高鸡传染性支气管炎病毒血凝抗原滴度途径及抗原灭活

将７株传染性支气管炎病毒（ＩＢＶ）标准株（Ｍ４１、Ｈ１２０、Ｈｏｌｔｅ、Ｇｒａｙ、Ｃｏｎｎｅｃｔｉｃｕｔ、Ｉｏｗａ６０９和Ｔ株）和６株分离株（ＮＩＢＶ、ＧＩＢＶ、Ｍ、ＳＨ、Ｊ和Ｈ株）分别接种于鸡胚，收获尿囊液，经浓缩后，用魏氏梭菌培养液处理，制备血凝抗原。其中，Ｈ１２０株血凝滴度最高，Ｔ、Ｍ、Ｊ和Ｈ株无血凝性。应用含有不同滴度ＩＢＶ母源抗体的鸡胚增殖病毒制备抗原，效价与用ＳＰＦ鸡胚增殖病毒制备的抗原效价一致。尿囊液经反复冻融后再制备抗原会使血凝价降低。抗原分别用甲醛、高碘酸钠、硼氢化钾和ＳＤＳ灭活，其中甲醛灭活效果最理想。抗原对氯仿敏感，对乙醚稳定。适宜浓度的Ｎａ＋、Ｍｇ２＋可显著提高抗原的血凝性