实验性鸡大肠杆菌病病理学动态变化

用致病性大肠杆菌O18分离株和／或低致病性禽流感病毒（Mildly pathogenic avian influenza virus ,MPAIV)接种10－12日龄SPF鸡。在接种后1－96h进行临床症状与大体病理变化、组织学观察发现：大肠杆菌接种组、MPAIV接种组和健康接种组除扑杀鸡外未见鸡死亡，MPAIV与大肠杆菌混合接种组除扑杀鸡外死亡率为24％。混合接种组的病变比大肠杆菌接种组出现的时间早，恢复也慢，各脏器的病理变化更严重。MPAIV主要引起各实质器官的坏死，结果表明，大肠杆菌经气管内接种后试验鸡主要表现为呼吸道的炎症反应；MPAVI可使鸡大肠杆菌病严重化。     

The lesional changes and pathogenesis in the kidney in african swine fever

African swine fever is a viral haemorrhagic disease of pigs which has been used as a model for the study of viral haemorrhagic diseases in man. The acute course of the disease is characterized by acute proliferative glomerulonephritis, with viral replication in mesangial cells and occasional focal necrosis of the renal tubular system; hyperplasia of the collecting ducts is associated with evident virus replication. Haemorrhages have been attributed to endothelial dysfunction, aggravated by virus replication in endothelial cells in the final stages of the disease. The renal interstitium displays intense oedema and an infiltrate largely composed of macrophages. Virus replication has also been observed in fibroblasts and in the smooth0muscle cells of arterioles and venules.In subacute-chronic forms of the disease, various types of glomerulonephritis are observed, ranging from mesangial proliferative glomerulonephritis to focal and segmental hyalinosis associated with immune-mediated phenomena. No striking changes are reported in the renal tubular system. Interstitial haemorrhages are associated with diapedesis due to immunologically mediated events. The interstitium has also been found to contain a lymphohistiocytic infiltrate with abundant plasma cells. No evidence has been reported of viral replication in any cell population.Abbreviations ASF African swine fever - ASFV African swine fever virus - C complement component - DNA deoxyribonucleic acid - HAD₅₀ 50% haemoadsorbing doses - Ig immunoglobulin - MPS mononuclear phagocytic system - PAS periodic acid-Schiff reagent     

猪瘟病毒E2蛋白在酵母中分泌表达条件的优化

影响外源基因在毕赤酵母中表达的因素很多，除了基因序列本身的内在特性外，表达条件对外源基因的表达量的高低也有着极显著的影响。本文对猪瘟病毒E2基因在毕赤酵母中不同的时间、不同的诱导型、不同的pH、不同的诱导剂量等方面表达量的差异进行了详细对比研究。结果表明，诱导后72～96h，重组E2蛋白的表达量最高。与单纯甲醇诱导相比，甘油／甲醇诱导后的表达量明显提高。在pH7．5和pH8．0表达E2蛋白是比较合适的。甲醇浓度在3％左右时E2蛋白的表达量较高。     

PCR结合分子杂交法检测鸡传染性支气管炎病毒

利用逆转录－ＰＣＲ（ＲＴ－ＰＣＲ）特异性扩增鸡传染性支气管炎病毒（ＩＢＶ）基因组中Ｍ基因和Ｎ基因之间一段核酸片段。以ｐＵＣ１９质粒载体将此片段克隆，用ＥｃｏＲＩ和ＨｉｎｄⅢ酶切此重组质粒，回收克隆片段后，制成生物素标记的核酸探针。用ＲＴ－ＰＣＲ及生物素核酸探针法分别对ＩＢＶ，ＩＢＤＶ，ＩＬＴＶ，ＭＤＶ及ＮＤＶ进行检测，结果证明该方法为ＩＢＶ特异性检测方法。对人工感染ＩＢＶ的ＳＰＦ鸡口腔棉拭样品进行跟踪检测，证明本方法能在ＳＰＦ鸡接毒后１～１０ｄ内检出ＩＢＶ。     

Pestivirus infections in Norway. Serological investigations in cattle, sheep and pigs.

Serum samples from 1,133 dairy cows (187 herds), 3,712 ewes (103 flocks) and 1,317 adult pigs (877 herds), were tested for neutralizing antibodies against the NADL strain of bovine virus diarrhoea virus. The prevalence rate of seropositive animals was 18.5% in cattle, 4.5% in sheep and 2.2% in pigs, such seroreactors being found in 28% of the cattle herds and 18% of the sheep flocks. In all three species the rate showed considerable herd and geographical variation. In cattle the seroreactor rate was similar in herds with normal reproduction and in 62 herds with problems of repeat breeding. Of 31 pig sera containing antibodies against the NADL strain, 27 were also positive in a neutralization test for antibodies against swine fever virus (Baker strain). However, all sera showed a higher titre of antibodies against the bovine strain than against the swine fever virus. It was concluded that the immune response of the pigs had been induced by ruminant pestivirus, and not by swine fever virus.     

关于林草地减沙效益计算研究

林草地减沙效益表现在固土、拦沙和防蚀三个方面。传统的用封闭径流小区试验法测定的林草地的减沙量实质上仅为林草地自身的固土量，用这种固土量来计算林草地的减沙效益是不完全的、片面的。     

影响马立克氏病毒感染的因素及疫苗免疫策略

马立克氏病毒是高度细胞结合性、嗜淋巴组织的α疱疹病毒,其致病过程包括淋巴细胞的溶细胞感染和潜伏感染以及易感鸡体内CD 4 T细胞的致瘤性转化。宿主的遗传抗性、细胞免疫、体液免疫以及相关细胞因子和淋巴细胞等对M DV的感染过程有重要影响。针对M D肿瘤抗原的靶向免疫应答的保护性抗原分子和宿主细胞因子疫苗是今后疫苗研究的方向。     

鸽新城疫病毒QL株—些理化及培养特性

本试验对鸽新城疫病毒QL株在鸡胚中的培养特性、血凝素热稳定性及对甲醛溶液、胰蛋白酶等理化因素的影响进行了测定，结果为QL株接种鸡胚后96h生长达高峰，QL株可耐受56℃40min,0.1%甲醛溶液能完全灭活QL株尿囊液，且仍保持较好的抗原性，0.5%胰蛋白酶37℃消化30min后，血凝性升高。试验结果为合理利用QL株生产鸽新城疫疫苗提供了实验依据。     

部分葡萄品种的病毒病鉴定及健康状况评价

应用血清学的酶联免疫吸附法(ELISA),对采自四川省内4个葡萄主产区内的34个葡萄品种,共计199份枝条样本进行了葡萄病毒病的检测和分析。在被测试的26个鲜食葡萄品种中,18个品种被1种或多种危险性的目标病毒所感染,品种感染率为69.2%;而在8个酿酒葡萄品种中,仅1个品种感染了危险性病毒,感染率为12.5%。在5个受测目标病毒和类型中,GLRaV-3的发生和危害最为普遍,其单个采样点的样本感染率为25.5%￣56.3%,其次为GVA0￣25.5%,GVB0￣12.5%和GLRaV-20￣4.5%,GFLV在本次试验中未被检测到。在每个取样点,感病品种一般所有单株都被同一种病毒感染,因此葡萄繁殖材料的引入是危险性病毒进入新产区的主要途径;而在生产实践中,高接换种方式会成倍增加葡萄病毒传播侵染的风险性。     

马立克氏病的发病机理及马立克氏病疫苗的免疫机理

本文综述了马立克氏病（MD）的发病机理和MD疫苗的免疫机制，表明IFN-γ的NO在MD致病机理中具有重要作用，它们在MDV溶细胞感染过程和潜伏感染过程中抑制了病毒的复制；特异性和非特异性免疫反应参与了疫苗免疫的过程，细胞毒性T细胞（CTLs）在特异性免疫反应中具有特别重要的作用。