Genomic variations and antigenic relationships among cytopathic rotavirus strains isolated in Quebec dairy herds.   总被引：1，自引：0，他引：1       下载免费PDF全文

S Dea  D Archambault  M A Elazhary    R S Roy 《Canadian journal of veterinary research》1986,50(1):126-129

Twelve isolates of bovine rotavirus, originating from eight dairy herds in Quebec known to have frequent epizootics of diarrhea in young calves in the last five years, were successfully propagated in cell cultures. The 12 isolates produced clear-cut plaques in BSC-1 cells and, except for one isolate, agglutinated human group "O" erythrocytes to an higher titer than bovine erythrocytes. Antisera to each isolate were produced in rabbits and used to study their antigenic relationships. All the isolates shared the group-specific immunofluorescent antigen and were antigenically related as demonstrated by the seroneutralization and hemagglutination-inhibition tests. However, the relationships to the Nebraska rotavirus was quite weak in cases of two Quebec isolates. When the genomes of the various isolates were compared by polyacrylamide gel electrophoresis, at least three different reproducible fractionation patterns could be identified.  相似文献   

Some diagnostic, biologic and morphologic characteristics of Francisella tularensis strains isolated from the ticks Ixodes ricinus (L.) in the Prague agglomeration   总被引：2，自引：0，他引：2  

D Málková  K Blazek  V Danielová  J Holubová  M Lavicková  Z Marhoul  J Schramlová 《Folia parasitologica》1986,33(1):87-95

Four infectious agents were isolated from the ticks Ixodes ricinus (L.) collected in the recreational area and park-forest of Prague. On the basis of cultivation, staining, biochemical, serologic properties, pathogenicity for animals and histological tests they were identified as Francisella tularensis with the following features: they are short, gram-negative rods of approximate dimensions of 0.3 X 0.8 micron, growing in enriched media after 3-4 day incubation at 37 degrees C. They form small circular, at first transparent, later greyish turbid colonies with regular rims. They are little active biochemically. They are susceptible to streptomycin and some broad spectrum antibiotics. They react positively with tularemic serum, but in lower titres than those in which this serum reacts with standard antigen. The microbes are highly pathogenic for mice, guinea-pigs, young rats, in which a massive bacteriemia occurs before death, but they do not kill rabbits. They multiply well in chick embryo, but do not grow in cell or tissue cultures. The most important histologic changes were observed in liver and spleen of mice. No pathologic changes were found in brain, lungs, heart, kidneys. Necroses were found in liver and in their marginal zones the microbes were present. Conspicuous were changes in numerous hepatocytes which became enlarged due to microbial multiplication and finally transformed into "sacs" packed with microbes. Histological and electronoptical examination showed that these are intracellular parasites fringed with a light lytic zone. Discussed is the problem to what extent the properties of the isolated strains are typical of F. tularensis as well as the importance of their detection from the aspect of epidemiology and differential diagnostics.  相似文献   

An enzyme immunoassay to measure canine circulating fibronectin     

O'Neill S  Boothby JT  Feldman BF 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1986,15(1):22-26

A competitive enzyme immunoassay has been used to detect and quantitate fibronectin in canine plasma. In this test, purified fibronectin, bound to microtiter plates, competes with plasma fibronectin for the conjugated antibody, rabbit-anticanine, fibronectin-horseradish peroxidase. The assay could detect fibronectin in purified standards from 58 ng/ml to 580 microgram/ml. The range of 1-100 microgram/ml was linear for plasma samples diluted 1:10, allowing samples with fibronectin concentrations from 10-1000 microgram/ml to be easily measured by this method. The mean normal fibronectin concentration of 132 dogs, by this method, was determined to be 320 +/- 74 microgram/ml.  相似文献   

Cytochemical properties of chicken blood cells resembling both thrombocytes and lymphocytes     

Swayne DE  Stockham SL  Johnson GS 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1986,15(2):17-24

Generally accepted criteria were used to identify typical nucleated thrombocytes and typical small lymphocytes in chicken-blood smears subjected to modified-Wright staining. Other cells, here referred to as "intermediate cells," were difficult to classify because in some aspects they resembled thrombocytes while they also had features typical of small lymphocytes. The "intermediate cells" had small, round or oval nuclei with coarsely condensed chromatin, characteristic of both thrombocytes and small lymphocytes. In addition, "intermediate cells" had moderately abundant cytoplasmic volumes, typical of thrombocytes but blue cytoplasm lacking both granules and vacuoles, which is characteristic of small lymphocytes. It made little difference to the thrombocyte count whether these cells were classified as thrombocytes or small lymphocytes; however, this decision made a substantial difference to the lymphocyte count in some chicken-blood smears. Most "intermediate cells" (351 of 410 cells examined) were nonfluorescent after treatment with formaldehyde gas. Furthermore, most "intermediate cells" failed to acquire characteristic pigments when subjected to either Grimelius staining (179 of 204 cells examined) or periodic acid-Schiff staining (173 of 206 cells examined). Typical small lymphocytes reacted in the same way, failing to fluoresce after gaseous formaldehyde treatment (65 of 65 cells examined) and failing to react during Grimelius staining (41 of 44 cells examined) or periodic acid-Schiff staining (21 of 21 cells examined). In contrast, almost all typical thrombocytes became fluorescent in response to gaseous formaldehyde (709 of 718 cells examined) and gave positive reactions when subjected to Grimelius staining (381 of 382 cells examined) or periodic acid-Schiff staining (322 of 326 cells examined). These findings suggested that "intermediate cells" should be classified as lymphocytes in differential cell counts.  相似文献   

New French law boosts industrial r&d     

Dickson D 《Science (New York, N.Y.)》1985,228(4703):1071

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福建省稻瘟病菌生理小种研究(续报)     

张学博  许文耀  林成辉 《福建农林大学学报(自然科学版)》1985,(4)

应用我国7个鉴别品种,鉴定了1980～1981年由我省7个地区37个县(市)采集分离的387个有效单孢菌株,区分为7群29个小种,其中ZB群为优势小种群,ZB_(15)为优势小种。 1975～1978年福建省稻瘟病菌生理小种区系组成相似,至1981年便发生了变化。但主要小种类型并无什么变化,而是小种组成比和地理分布范围的变更。其特点是侵染我省大面积栽培的珍尢系统品种的ZB群小种迅速增加,地理分布范围扩大。至1981年全省7个地区均以ZB群为优势小种群,ZB_(15)上升为优势小种,取代了过去致病力弱的优势小种ZG_1。文中还对稻瘟病菌的变异和稳定性作了讨论。关键词:稻瘟病菌;生理小种;中国鉴别品种;珍龙系统品种实践证明,利用抗病品种是防治稻瘟病的一项经济有效的措施,但品种抗性与稻瘟病菌的变异、小种区系组成的变化密切相关。因此,稻瘟病菌生理小种区系组成的变化及其消长规律的研究,是抗瘟育种品种布局和品种坑性变化预测的重要基础工作。在1973～1978年对我省稻瘟病菌生理小种研究的基础上,本文报导了1980～1981年福建稻瘟病菌生理小种的鉴定和1978、1981年小种区系组成的变化情况。  相似文献   

France seeks joint European research     

Dickson D 《Science (New York, N.Y.)》1985,228(4700):694

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An embattled agency: model research     

Critchlow DT 《Science (New York, N.Y.)》1985,230(4729):1030-1031

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Verification of nuclear testing     

Evernden JF 《Science (New York, N.Y.)》1985,228(4701):792-794

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Issues of gene regulation: DNA methylation     

Ginder GD 《Science (New York, N.Y.)》1985,228(4701):865-866

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