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M Kańtoch W Falecka B Litwińska J Lityńska W Sadowski 《Acta microbiologica Polonica》1977,26(4):429-438
Experiments discussed in this paper aimed at obtaining, using Cercopithecus aethiops monkeys information on immunogenic activity of measles virus as well as kinetic and persistence of immunological reaction at active and inactivated virus. 相似文献
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Summary Transplantation of a small fragment of the ileum beneath the kidney capsule in syngenic mice results in the formation of a cyst lined with proliferating intestinal epithelium. The duration of the cell cycle in this epithelium was determined (using tritiated thymidine and the FLM method) as 14.5 h, as compared with 11.5 h in the intestinal epithelium in situ. We conclude that the intestinal content has little effect on the cell cycle of epithelial cells of the small intestine. 相似文献
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Summary Albino mice were injected intraperitoneally with tritiated thymidine and killed 1/2 and 30 h later. Pieces of ileum were excised and fixed. Tissue sections were hydrolyzed with 5 N HCl at 21° C for 1/2, 1, 2, 3, 4 and 6 h, some sections remained unhydrolyzed. Both the hydrolyzed and nonhydrolyzed sections were autoradiographed. Grain counts per labelled nucleus of either cryptal (DNA-synthesizing) or villous (DNA-nonsynthesizing) cells nonhydrolyzed and hydrolyzed for various time intervals were recorded.The results indicate, that the grain count of nonhydrolyzed, labelled nuclei from cryptal cells was by 1.49 higher than that of villous cells demonstrating the rate of grain counts diminution caused by cell divisions.Hydrolysis caused a diminution of grain count of cryptal cells by approximately 15% higher than that of the grain count of villous cells.Financial support was partially obtained from grant MR II.1.We wish to thank Dr. W. Sawicki for his supervision, advice and encouragement throughout this work 相似文献
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In nucleus of chick embryo four pre-rRNA of molecular weight of 3.43, 2.93, 2.36 and 1.87 X 10(6) were found in addition to the heterogeneous population of "giant" RNA molecules larger than 4.5 X 10(6) daltons, partially polyadenylated, with few methyl groups and numerous double-stranded regions. 相似文献