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Effect of actinomycin D and guanidine on the formation of a ribonucleic acid polymerase induced by foot-and-mouth-disease virus and on the replication of virus and viral ribonucleic acid 总被引:5,自引:0,他引:5 下载免费PDF全文
The RNA-dependent RNA polymerase induced in baby-hamster kidney cells by infection with foot-and-mouth-disease virus can be detected as early as 60min. after infection, which is 60min. before viral RNA synthesis commences. The time at which the polymerase can first be detected coincides with the latest time at which actinomycin D (50mug./10(7) cells) or guanidine (1mg./10(7) cells) inhibits virus replication. However, by increasing the concentration of guanidine, viral replication can be inhibited later in the growth cycle, casting doubt on the validity of the hypothesis that guanidine acts specifically on the formation of the viral RNA polymerase. 相似文献
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Total skin collagen is greatly increased in women with hirsuties. This is presumably due to androgen, whether locally produced or circulating. 相似文献
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Humoral immune response to the bovine immunodeficiency-like virus in experimentally and naturally infected cattle. 总被引:15,自引:7,他引:8 下载免费PDF全文
Calves inoculated with bovine immunodeficiency-like virus (BIV) produced virus-specific antibodies that could be detected from 2 weeks to 2.5 years postinoculation by using both indirect fluorescent-antibody and Western immunoblot assays. Antibodies were primarily to p26. Virus and BIV-specific antibodies were isolated from calves given BIV-infected blood. Antibodies to BIV proteins were found in sera from naturally infected cattle. 相似文献
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Acetylcholine receptor in a C2 muscle cell variant is retained in the endoplasmic reticulum 总被引:12,自引:10,他引:2 下载免费PDF全文
We have examined the properties and intracellular localization of acetylcholine receptors in the C2 muscle cell line and in a variant (T-) that accumulates AChR intracellularly. On immunoblots, the subunit structures of the AChR from wild-type and T- cells were similar except that the gamma and delta subunits of the variant AChR had altered mobilities. Digestion with endoglycosidases H and F demonstrated that this difference results from a failure of high-mannose N-linked oligosaccharides on AChR subunits to be processed to complex forms in the variant. N-linked glycosylation of other proteins in the variant was normal. When examined by immunocytochemistry, the distribution of internal AChR in wild-type cells was consistent with a location both in the endoplasmic reticulum and in the Golgi. Variant cells, however, showed no evidence of Golgi staining. Subcellular fractionation experiments also demonstrated AChR in the Golgi fractions of wild-type cells, but not in those derived from T- cells. We conclude that in T- myotubes most of the AChR fails to be transported out of the endoplasmic reticulum. 相似文献