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41.
参考 Genbank收录的 TGEV- Miller株的基因序列 ,自行设计合成 1对引物 (TGEVP5 /P6 ) ,对不同代次的 TGEV疫苗弱毒 STC3及种毒 、种毒 进行了 RT- PCR扩增 ,产物经琼脂糖凝胶电泳分析 ,均出现 1条大约 12 6 2 bp的目的条带 ,经 Eco R 酶切 ,都产生了 871bp和391bp左右的两个片段 ,与预期大小相符。将种毒 RT- PCR扩增目的条带回收纯化后克隆入PMD18- T载体中 ,转化宿主菌 DH5 α,挑选阳性克隆 (命名为 PTs) ,提取重组质粒 ,用 Hpa 、Eco R 对重组质粒进行酶切鉴定以及 PCR扩增 ,然后进行序列测定 ,并进行了序列分析 ,证实与国外标准毒株 Miller、Fs772 / 70、Purdue、TO14等有较高的同源性 相似文献
42.
本文应用聚合酶链反应(PCR)技术从构建的新城疫病毒(NDV)cDNA文库中扩增含编码F糖蛋白前体──Fo酶切位点序列的359bp的F蛋白基因cDNA片段。将此359bpcDNA片段经光敏生物素标记后,即成NDV-cDNA探针。该探针能特异性地从感染的尿囊液中检测出NDV强毒株和疫苗毒株的基因组RNA,而不与IBDv-dsRNA、AIBv-ssRNA、EDS76-dsDNA、MDV-dsDNA,FPV-dsRNA及AILV-dsDNA发生交叉杂交反应。试验结果表明:尽管该探钎含有编码Fo蛋白酶切位点序列的碱基顺序,但它还是不能把NDV的强、弱毒株区分开。这说明NDV强、弱毒株比区域内的碱基存在着相当大的同源性。不过,此探针对NDV来说具有特异性,这就为NDV的诊断技术开创了基因水平检测的新途径。 相似文献
43.
李厚达 《扬州大学学报(农业与生命科学版)》1987,(4)
用酶联免疫吸附试验(ELISA),对2群鸡的鸡蛋清和1株鸡的马立克氏病疫苗进行检测,发现2群鸡的鸡蛋清中,鸡白血病病毒的阳性率分别是11%和29%,鸡马立克氏病冻干苗隐藏鸡白血病病毒群体特异性(gs)抗原的阳性率为100%。本文指出我国禽苗可能带有鸡的白血病病毒,分析讨论了鸡白血病病毒的垂直传递和水平传播的规律,提出在曾祖代和祖代鸡群中,采用ELISA试验,检测鸡蛋清,能减少以至根除鸡的白血病。 相似文献
44.
Jeanne Dijkstra L. Bos H. J. Bouwmeester Tutung Hadiastono H. Lohuis 《European journal of plant pathology / European Foundation for Plant Pathology》1987,93(3):115-133
Two potyvirus isolates, one from germplasm of yard-long bean (Vigna unguiculata ssp.sesquipedalis) introduced into the Netherlands, and another one from soybean plants (Glycine max) in Indonesia, were compared with two virus isolates of blackeye cowpea mosaic virus (BICMV) from the USA and a Moroccan isolate of cowpea aphid-borne mosaic virus (CAMV). It is proposed that all five isolates be now considered BICMV on the basis of host ranges, symptoms and serology. From our results, and a reassessment of the literature it is suggested to drop the name CAMV in favour of BICMV.Samenvatting Twee potyvirussen, de een in Nederland ingevoerd met genenmateriaal vanVigna unguiculata ssp.sesquipedalis en de ander uit planten van sojaboon (Glycine max) in Indonesië, werden vergeleken met twee isolaten van blackeye cowpea mosiac virus (BICMV) en een Marokkaans isolaat van cowpea aphid-borne mosaic virus (CAMV). Op grond van waardplantenreeksen, symptomen en serologie stellen de auteurs voor om alle vijf isolaten te beschouwen als BICMV. Gebaseerd op de verkregen resultaten en een kritische beschouwing van de literatuur wordt de aanbeveling gedaan om de naam CAMV te laten vallen ten gunste van BICMV. 相似文献
45.
根据长江流域夏秋季的气候特点,采用杂交、回交、系统分离、活蛹缫丝和多代高温多湿环境定向培育等育种方法,分别育成了中系蚕品种“浒花”和日系蚕品种“秋星”。两者都具有抗性强、丝量高、茧丝质优以及繁育容易等特点。其一代杂交种经多次实验室鉴定、农村生产鉴定、试养以及全国蚕品种审定结果表明:该新品种体质强健、孵化、眠起、老熟齐一,茧丝量高,茧层率22%;鲜毛茧出丝率15—16%,茧丝品质优良、解舒率74%,净度93分,茧丝纤度2.53/D,茧丝长超1000m。 相似文献
46.
C. Soria M. L. Gomez-Guillamon J. E. Duffus 《European journal of plant pathology / European Foundation for Plant Pathology》1991,97(5):289-296
The agent causing a yellowing disease of melon (Cucumis melo), which results in severe losses in crops under plastic on the coastal plains of southeast Spain, was shown to be transmitted in a semipersistent manner by the greenhouse whitefly (Trialeurodes vaporariorum Westwood). The agent was transmitted by grafting, but not by mechanical inoculation or through seeds. The agent was acquired in the minimum period tested (2 h) and could infect plants in an infection feeding interval of 6 h.
Capsella bursa-pastoris, Cucumis melo, C. sativus, Cucurbita moschata, Cichorium endivia, Lactuca sativa andTaraxacum officinale were found susceptible.Results suggest that the yellowing disease affecting melon crops in the southeast of Spain is due to a pathogen similar to beet pseudo yellows virus, but this has to be confirmed by serology. 相似文献
47.
家蚕质型多角体病毒苏州核包涵体小种的纯化 总被引:1,自引:0,他引:1
从BmCPV_t内发现和分离出一株新的核包涵体小种,初步命名为家蚕质型多角体病毒—苏州核包涵体小种(Cytoplasmic Polyhedrosis Virus——Suzhou nuclear polyhedra forming strain,简称CPV——Suzhou N strain),家蚕感梁CPV——Suzhou N Strain引起的多角体病,与国内外已知的CPV各变异株不同。本病蚕的多角体只在中肠组织圆筒形细胞核内检出,多角体内有许多病毒粒子,病毒粒子球状,具有核蛋白紫外吸收特征性光谱和较强的感染活性,病毒核酸初步鉴定为dsRNA。 相似文献
48.
G Castrucci F Frigeri S Ranucci M Ferrari V Cilli B Pedini P Nettleton F Caleffi V Aldrovandi A J Herring 《Comparative immunology, microbiology and infectious diseases》1984,7(1):1-10
Three strains (479 C, 778 TL, 982 LE) of infectious bovine rhinotracheitis (IBR) virus isolated from latently infected calves were compared with the prototype strain of IBR virus (LA strain) in studies which included restriction endonuclease analysis, experimental infection, and reciprocal cross protection tests in cattle. From the restriction endonuclease analysis it appeared that the 3 "latent" viruses were derived from the same isolate, and that it differed slightly from the LA strain. However, latency does not seem to have affected the pathogenicity or the immunogenicity of the virus. This is demonstrated by the identical clinical and virologic response of calves subjected to experimental infection with the various strains under study, and by the finding that when the LA strain and a "latent" strain (982 LE) were tested in cross protection tests in cattle, they proved to be mutually protective. 相似文献
49.
J. F. Antoniw R. F. White 《European journal of plant pathology / European Foundation for Plant Pathology》1983,89(6):255-264
This review describes the discovery and identification of the pathogenesis-related proteins (PRs) from tobacco. In crude leaf extracts the PRs are distinguished from the proteins in uninfected plants by their solubility at pH 3, resistance to a range of proteases, and mobility in polyacrylamide gels upon electrophoresis (PAGE) in non-denaturing conditions. PAGE has been used as a qualitative and semi-quantitative assay for PRs, and their migration in gels made from different acrylamide concentrations has been used to identify charge and size isomers and electrophoretically identical PRs in different tobacco cultivars. The subunit composition and molecular weight (mol. wt) of the four PRs identified first in Xanthi-nc were determined by SDS-PAGE; staining the gels has shown that these same four proteins in Samsun NN did not contain carbohydrate, lipid or nucleic acid, nor were they isozymic forms of twenty five enzymes known to increase in activity following infection with TMV. Evidence suggests that most of the PRs in Xanthi-nc and Samsun NN are extracellular.The purification of several PRs from Xanthi-nc, Samsun NN and other tobaccos is described, as well as their mol. wt, subunit and amino acid composition. PRs 1a, b and c consist of a single polypeptide and have similar mol. wt and amino acid compositions. Antisera prepared against purified Xanthi-nc b1 protein have been used to determine serological relationships between PRs and form the basis of a very sensitive quantitative assay using ELISA. The regulation of synthesis of some PRs has been shown to involve translational control. 相似文献
50.
Rob W. Briddon Patricia Lunness Ian D. Bedford Leony C. L. Chamberlin Theo Mesfin Peter G. Markham 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(4):397-400
The cause of a streak disease of pearl millet (Pennisetum glaucum), originating from Nigeria, has been attributed to a geminivirus belonging to the African streak virus cluster. A full-length, infectious clone of the virus was obtained which was transmissible by the vectorCicadulina mbila (Naudé). Analysis of the complete nucleotide sequence of the coat protein gene of this virus shows it to be most closely related to sugarcane streak virus. The possible evolutionary implications of this finding are discussed. 相似文献