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891.
Comparison of the in vitro effects of colchicine and its derivative colchiceine on chondrocyte morphology and function 总被引:1,自引:0,他引:1
Colchiceine is a colchicine-metabolite which has been reported to inhibit axonal transport although not binding to brain tubulin. In the present study, colchiceine was shown not to depolymerize cytoplasmic microtubules, nor to mimic other effects of colchicine on the ultrastructure of cultured chondrocytes. In addition, the synthesis of proteoglycans was inhibited by colchicine but slightly stimulated by colchiceine. These results support the idea that the disturbances in cultured chondrocytes caused by colchicine are specifically related to a loss of cytoplasmic microtubules. 相似文献
892.
Administration of alcohol to rats through drinking water for 8 weeks produced a significant decrease in the liver vitamin A stores without causing any change in the plasma vitamin A levels. Treatment of the alcoholic rats with propylthiouracil for 2 weeks restored the liver vitamin A reserves to control levels. 相似文献
893.
Effects of cadmium on the immune system of mice 总被引:1,自引:0,他引:1
S. Müller K. -E. Gillert Ch. Krause G. Jautzke U. Gross T. Diamantstein 《Cellular and molecular life sciences : CMLS》1979,35(7):909-910
Summary Chronic oral exposure of mice to Cd++ inhibits cell-mediated immunity of delayed type hypersensitivity induced by sheep red blood cells (SRBC). No effect was detected on humoral immune response to SRBC. Spleen cells derived from mice exposed to Cd++ showed in vitro enhanced response to T and B cell mitogens. These results demonstrate that Cd++ exposure alters the immune system of mice.Dedicated to Prof. Georg Henneberg on the occasion of his 70th anniversary on 12.10.1978.Acknowledgments. Supported by a grant from the Umweltbundesamt. We thank Ms Odenwald, Ms Schulz, Klinikum Steglitz, and Ms Emeis, Robert Koch-Institut Abt. Immunologie, for the excellent technical assistance. 相似文献
894.
R. S. U. Baker 《Cellular and molecular life sciences : CMLS》1976,32(1):98-99
Summary Mouse cells productively infected with Moloney leukaemia virus (MuLV) underwent senescence in a manner similar to control cells, although they recovered more readily as an established line. Rapidly growing cell lines were also obtained following simian virus 40 (SV40) infection of senescent cells. However, superinfection of senescent MuLV-producing cells by SV40 led to slower growing cells with a reduced output of infectious MuLV. 相似文献
895.
896.
Similarity of the Cin1 repetitive family of Zea mays to eukaryotic transposable elements 总被引:5,自引:0,他引:5
N S Shepherd Z Schwarz-Sommer J Blumberg vel Spalve M Gupta U Wienand H Saedler 《Nature》1984,307(5947):185-187
It has been suggested that the middle repetitive class of sequences that make up a large proportion of the eukaryotic genome have been amplified and dispersed by DNA transposition. Transposition is a phenomenon first postulated by Barbara McClintock on the basis of her genetic analysis of mutants in Zea mays. Since then, DNA transposition has been studied genetically in various plant systems and is well documented on the molecular level in both prokaryotes and eukaryotes. This has included the isolation of DNA inserts at various loci in several plants; however, the prevalence of transposition in plants is not established. We report here DNA nucleotide sequence data which show that some members of the Cin1 middle repetitive family of maize have features characteristic of known transposable elements. One cloned Cin1 repeat has a 6-base pair (bp) perfect inverted repeat sequence at its ends. The terminal five base pairs (5' TGTTG . . . CAACA 3') are identical to the termini of Drosophila copia transposable elements. Two other Cin1 alleles are flanked by 5-bp direct repeats. A comparison is made with the long terminal repeat (LTR) of the copia-Ty1-retrovirus families of moveable genetic elements. 相似文献
897.
898.
899.
Zusammenfassung Die optischen Antipoden der hypolipidämisch wirkenden Substanz 2-Methyl-2-[p-(1,2,3,4-tetrahydro-1-naphthyl)-phenoxya]-propionsäure (CH 13437) zeigen im Rattenversuch gleichstarke hypolipidämische Wirkung und gleichartige Aktivitsätsänderungen von Leberenzymen des Kohlenhydrat- und Lipidstoffwechsels. 相似文献
900.
S. Lindgren Å. Lindquist B. Lindeke U. Svensson B. Karlén R. Dahlbom M. R. Blair Jr 《Cellular and molecular life sciences : CMLS》1970,26(11):1232-1233
Zusammenfassung Eine Anzahl von Antagonisten zu Oxotremorin wurden durch kleine Modifikationen der Struktur des Oxotremorins erhalten. Die aktivste Verbindung, N-(1-Methyl-4-pyrrolidino-2-butinyl)pyrrolidon, ist mehr als sechsmal wirksamer als Atropin und hat eine grössere Spezifizität mit Bezug auf das Zentralnervensystem. 相似文献