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1.
1 病原
鸡传染性支气管炎（IB）是由鸡传染性支气管炎病毒（IBV）感染引起的一种急性高度接触性呼吸道和生殖道疾病，表现为呼吸型，肾型，肠型，腺胃型等多种病型，在全世界流行。1931年sehalk和hawn首次报道了此病，以后人们不断分离出新的血清型，到目前为止全世界已分离出30多个血清型和更多的突变株。大肠杆菌自1885年发现以来现也已有多种血清型及变种。大肠杆菌主要引起腹泻和败血症。近年来在临床实践中常常遇到的是由传染性支气管炎感染引发慢性呼吸道病之后， 相似文献
2.
鹅副粘病毒的分离与鉴定 总被引：5，自引：0，他引：5
采用鸡胚接种法从安徽凤阳某患病鹅群中分离到一株病毒。经HA与HI试验、血清中和接种鸡胚试验、病毒回归试验确认为鹅副粘病毒，并命名为WF00G株，参照新城疫病毒毒力的判定的标准及其方法，测定该分离株的鸡胚最小致死量平均死亡时间（MDT）、1日龄鸡脑接种致病指数（ICPI）和6周龄鸡静脉内接种致病指数（IVPI）分别为44.8h、1.81和2.32，结果表明该分离株具有与新城疫病毒（NDV）速发型相类似的毒力，属强毒力毒株。 相似文献
3.
海水网箱养殖尖吻鲈体表溃烂病致病菌的研究 总被引：2，自引：0，他引：2
本研究证实河弧菌生物Ⅰ型是尖吻鲈（Latescalcarifer）体表溃烂病的致病菌．从患病尖吻鲈病灶上分离到34株菌，其中4株菌为强毒菌株，这4株菌进行人工感染，死亡率均为100％，症状与自然发病相似．根据这4株菌的形态及生理生化特征，这4株菌应归入河弧菌生物Ⅰ型（VibriofluvialisbiovarⅠ）． 相似文献
4.
目的:研究gga-miR-29b-3p对马立克氏病(MD)肿瘤转化细胞侵袭和原癌基因Meq表达的影响.方法:选取SPF白来航鸡在感染马立克氏病病毒(MDV)后引发的内脏淋巴瘤为样本,通过实时荧光定量PCR检测gga-miR-29b-3p的表达情况;利用在线生物软件对gga-miR-29b-3p潜在的靶基因进行功能分析.以该miRNA为研究对象,MDV转化细胞系MDCC-MSB1为试验材料,分别转染miRNA激动剂或阴性对照,检测细胞侵袭相关基因MM P2和MM P9以及MDV原癌基因Meq的表达情况.结果:Gga-miR-29b-3p在感染MDV白来航鸡的肿瘤化脾脏和肝脏淋巴瘤中均显著低表达.信号通路方面miRNA的预测靶基因分别参与FoxO信号通路、mTOR信号通路、Jak-STAT信号通路、Toll样受体信号通路、ErbB信号通路、VEGF信号通路和细胞凋亡等,这些信号通路可参与肿瘤发生进程.转染miRNA激动剂后,MMP2和MMP9基因的表达量在48 h显著下调(P<0.05);Meq基因在48 h表达显著下调(P<0.05).结论:Gga-miR-29b-3p抑制细胞侵袭和病毒原癌基因的表达,其潜在靶基因能够介导肿瘤发生,提示该miRN A可能参与M D肿瘤转化过程. 相似文献
5.
HVT注苗鸡和未注苗鸡．分别以AIDV强毒接种感染和同居感染,用琼脂扩散试验（AGPT）检测各鸡群不同时期羽囊MDV抗原和抗体。结果显示,HVT苗可使实验鸡羽囊中MDV抗原检出时间推迟,阳性检出率显著降低：而羽囊中MDV抗体检出情况与此正好相反,检出时间早,阳性率高。 相似文献
6.
本文采集产蛋量突然下降的疑似发生EDS—76病鸡群中产软壳蛋鸡的输卵管为病料,经鸭胚传代,分离到一株血凝性病毒(FE_1株).该病毒株对氯仿不敏感,耐酸(PH3.0),通过与EDS—75—AV—127株及新城疫阳性血情所做的交叉血凝抑制试验表明,FE_1株与AV—127株的抗原性相同,而与新城疫病毒无抗原相关性.因此证明FE_1株端病毒属EDS—76病毒. 相似文献
7.
病毒主要是由蛋白质外壳及其包被的核酸所组成,病毒依其核酸类型可分为RNA病毒和DNA病毒,其中RNA病毒多数是单链;DNA病毒多数为双链．病毒核酸还有正、负链的区别：凡碱基排列顺序与mRNA相同的单链DNA或RNA,称（＋）DNA或（＋）RNA链,凡碱基排列顺序与mRNA链互补的单链DNA或RNA,称（-）DNA或（-... 相似文献
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《赣南师范学院学报》2013,(3):41-44
由柑橘衰退病毒(Citrus tristeza virus,CTV)引起的柑橘衰退病是柑橘生产上重要的病害之一,在全世界各柑橘产区均具有不同程度的发生.本文结合相关文献对柑橘衰退病毒分子特性、株系分化及检测方法进行综述,并就柑橘衰退病毒在抗病毒基因工程,弱毒株筛选以及弱毒株交叉保护机理等方面的研究做进一步展望. 相似文献
9.
用不同方法测试了从河南（HN9801）、陕西（XN9906）鸽副粘病毒分离株的致病性。结果，HN9801，XN9906分离毒株对1日龄SPF雏鸡的脑内接种致病指数分别为1．2，0．9，对6周龄SPF鸡静脉接种致病指数分别为0．7、0．5，分离毒株对8周龄左右鸽有很强的致病性。免疫保护实验表明：两株鸽分离株间有较好的交叉保护性，这为进一步防制该病奠定了基础。 相似文献
10.
猪繁殖与呼吸综合征（PRRS）是危害养猪业的一种高度传染性疾病，在临床上以母猪流产、死产等繁殖障碍，以及仔猪呼吸道症状和高死亡率为特征。自1996年我国首次报道PRRS以来，现该病已在全国各地广泛流行，给养猪业造成了严重的经济损失。对豫北地区PRRS地方株分离鉴定结果表明，分离毒株属于美洲型。自2001年6月至2003年12月，对豫北地区规模化猪场进行PRRS抗体检测，被检血清2403份，其中阳性血清1520份，阳性率为63．25％，阳性率较高。 相似文献
11.
根据不同的土壤类型,从江苏省苏北地区6市采集土样422份,分离出苏云金杆菌76株.血清学分析表明,它们分属于H_3、H_7、H_10、H_21和H_43型,另一株为自凝菌.通过对76个分离株的生物毒力测定,筛选出4林对赤松毛虫、小菜蛾、玉米螟等具有高毒力的菌株,为开发高效苏云金杆菌杀虫剂提供了重要的菌种资源. 相似文献
12.
Mo Kai-kun Lyu Chen-fei Cao Shang-shang Li Xia Xing Gang Yan Yan Zheng Xiao-juan Liao Min Zhou Ji-yong 《Journal of Zhejiang University. Science. B》2019,20(9):740-752
Journal of Zhejiang University-SCIENCE B - Fowl adenovirus serotype 4 (FAdV-4) strain SD1511 was isolated from chickens with severe inclusion body hepatitis and hydropericardium syndrome in... 相似文献
13.
We extracted six Hong Kong brown seaweed species with hot water for their antiviral properties. The cytotoxicity and antiviral activity of these extracts were tested by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenlytetrezolium bromide] method, cytopathic effect reduction assay, and plaque reduction assay. The antiviral effect was further determined by flow cytometric analysis. The results showed that most of these extracts inhibited the propagation of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) standard strains with very low cytotoxicity to the host cells. The extracts ofHydroclathrus clathratus and Lobophora variegata showed more potential anti-HSV activities than the extracts of the other four seaweeds. They also had moderate anti-respiratory syncytial virus (RSV) activities but could not inhibit influenza A virus. Hydroclathrus clathratus was further extracted by diluted acid and alkali and the antiviral effects of the extracts were also detected. The result showed that the hot water extract contained the main carbohydrate components that exhibited the antiviral activities against various strains of HSV, including the acyclovir-resistant strain. HI-3, a compound fractionated from this hot water extract, showed a dose-dependent anti-HSV activity in flow cytometric analysis and plaque reduction assay. 相似文献
14.
Molecular cloning and nucleotides sequence analysis of G1 genome segment of hantaan virus Z10 strain
Liang Wei-feng Shen Yue-hong Ma Yi-lin Zhao Nian-feng Chen Ya-gang Zhu Zhi-yong Xu Xiao 《浙江大学学报(A卷英文版)》2000,1(2):207-211
The molecular cloning of the G1 genome segment of the Z10 strain of Hantaan virus and analysis of the first gene data on the currently widely used Hantavirus vaccine strain in China
are presented. The G1 genome segment of Z10 virus was amplified by the method of RT-PCR, and the products were cloned into the pGEM-T vector after identification and
purification. The clone was sequenced by Sanger’s dideoxy chain termination method. The 1449 bases of the Z10 G1 genome segment, and the coding for 483 amino acids were determined. The base compositions for the G1 segment RNA determined from cDNA sequence information, were 20.6% A, 21.6% G, 18.8% C and 30.0% U. These values are similar
to those of the 76/118, Lee and SR virus. As compared to the Z10 G1 segment, the sequence homology at the nucleotide level is 87% (76/118, type I), 86% (Lee, type I), 86% (Hojo, type I), 67%
(R22, type II), and 59% (K22, type III). The Z10 virus G1 protein amino acid sequence identity with other Hantaan viruses (94–95% homology) was higher than that with Seoul type viruses
(77–80%). More amino acid sequence heterogeneity between the Z10 and 76/118 was observed in the N terminal, especially the diverging cluster of ten amino acids at position 84 to 93 of the
Z10 virus G1 protein. Conclusion: (1) The Z10 strain is one of the Hantaan viruses. (2) The important region of the Z10 G1 segment was conservative. (3) Although substantial divergence of nucleotide sequences of the G1 genome segment was found between the Z10 strain and other type I Hantaviruses, relatively high amino acid sequence homology was shown among them. Thus, good immune
protection could be obtained with the inactivated Meriones unguiculatus kidney cell vaccine against other strains of Hantaviruses. 相似文献
15.
Rui CHEN Shao-hong LU Qun-bo TONG Di LOU Dong-yan SHI Bing-bing JIA Guo-ping HUANG Jin-fu WANG 《Journal of Zhejiang University. Science. B》2009,10(7)
The dense granule protein 4 (GRA4) is a granular protein from Toxoplasma gondii, and is a candidate for vaccination against this parasite. In this study, the plasmid pcDNA3. 1-GRA4 (pGRA4), encoding for the GRA4 antigen, was incorporated by the dehydration-rehydration method into liposomes composed of 16 mmol/L egg phosphatidylcholine (PC), 8 mmol/L dioleoyl phosphatidylethanolamine (DOPE), and 4 mmol/L 1,2-diodeoyl-3-(trimethylammonium) propane (DOTAP). C57BL/6 mice and BALB/c mice were immunized intramuscularly three times with liposome-encapsulated pGRA4 to determine whether DNA immunization could elicit a protective immune response to T. gondii. Enzyme-linked immunosorbent assay (ELISA) of sera from immunized mice showed that liposome-encapsulated pGRA4 generated high levels of IgG antibodies to GRA4. Production of primary interferon (IFN)-γ and interleukin (IL)-2 in GRA4-stimulated splenocytes from vaccinated mice suggested a modulated Th1-type response. 72.7% of C57BL/6 mice immunized with liposome-encapsulated pGRA4 survived the challenge with 80 tissue cysts of ME49 strain, whereas C57BL/6 mice immunized with pGRA4 had only a survival rate of 54.5%. When immunized BALB/c mice were intraperitoneally challenged with 103 tachyzoites of the highly virulent RH strain, the survival time of mice immunized with liposome-encapsulated pGRA4 was markedly longer than that of other groups. Our observations show that liposome-encapsulated pGRA4 enhanced the protective effect against infection of T. gondii. 相似文献
16.
应用Con-A亲和层析方法从两株Den2病毒(New Guinea C株和从中国海南省分离的H-87株)感染的C6/36细胞膜中分离的糖蛋白,发现了一种感染细胞中特有的蛋白质。经SDS-PAGE证明该蛋白分子量约46000D,分析其为Den 2病毒的非结构蛋白NS1。并利用Western blot筛选出针对该蛋白4种单克隆抗体。 相似文献
17.
采用鸡胚接种法从安徽凤阳某患病鹅群中分离到一株病毒。经HA与HI试验、血清中和接种鸡胚试验、病毒回归试验确认为鹅副粘病毒 ,并命名为WF0 0 G株。参照新城疫病毒毒力判定的标准及其方法 ,测定该分离株的鸡胚最小致死量平均死亡时间 (MDT)、1日龄鸡脑接种致病指数 (ICPI)和 6周龄鸡静脉内接种致病指数 (IVPI)分别为 4 4 8h、1 81和 2 32 ,结果表明该分离株具有与新城疫病毒 (NDV)速发型相类似的毒力 ,属强毒力毒株。 相似文献
18.
Ge Song Jia-yu Wu Yan Xie Yong Liu Ya-juan Qian Xue-ping Zhou Jian-xiang Wu 《Journal of Zhejiang University. Science. B》2017,18(12):1075-1082
Potato virus S (PVS) often causes significant losses in potato production in potato-growing countries. In this study, the ordinary strain of PVS (PVSO) was purified from PVS-infected potato plants and used as the immunogen to produce hybridomas secreting monoclonal antibodies (MAbs). Five highly specific and sensitive murine MAbs (1A3, 16C10, 18A9, 20B12, and 22H4) against PVS were prepared using conventional hybridoma technology. Using these MAbs, tissue print-enzyme-linked immunosorbent assay (ELISA), dot-ELISA, and double-antibody sandwich (DAS)- ELISA were developed for sensitive and specific detection of PVS infection in potato plants. The results of sensitivity assays revealed that PVS could be reliably detected in PVS-infected leaf crude extracts diluted at 1:10 240 and 1:163 840 (w/v, g/ml) in phosphate buffer saline (PBS) by dot-ELISA and DAS-ELISA, respectively. Twenty-two samples collected from potato fields in Yunnan Province, China were tested for PVS infection using the serological assays we had developed, and 14 of them were found to be positive. This indicates that PVS is now prevalent in potato fields in Yunnan Province. 相似文献