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991.
J H Saurat E Gluckman L Didierjean 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(4):355-356
By means of indirect immunofluorescence with human sera it has been demonstrated that cytoplasmic components of the basal cell layer showed antigenic differences as compared to the upper cell layers. Moreover there were differences whether the cells were involved in a mucous, a parakeratinized or an orthokeratinized differentiation. 相似文献
992.
Daniela Guerra Patrizia Romano C. Zambonelli 《Cellular and molecular life sciences : CMLS》1981,37(7):691-693
Summary In resting cells of diploidSaccharomyces cerevisiae strains sulfur dioxide induces at very high frequency: a) respiratory deficinet mutants: b) mutants with altered methionine metabolism. In growing cells the following kinds of mutants appear: a) revertants for respiration; b) mutants altered in the methionine metabolism; c) SO2-resistants. It is suggested that sulfur dioxide acts as a selective agent through the induction SO2-resistant mutantsAcknowledgments. This investigation was supported by grant of C.N.R., Roma. The authors are grateful to Prof. Domenico L. Palenzona for helpful comments and suggestions. 相似文献
993.
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Limited hydrolysis of gene 32 protein by various proteinases results in the production of three stable cleavage products. Two of these products show an affinity for native T4 DNA cellulose that the uncleaved protein does not exhibit. A model for proteolytic cleavage and for the total unwinding of DNA in advance of the replication fork is discussed in terms of this unusual binding affinity. 相似文献
996.
H. E. Gray S. E. Wenzel W. G. Luttge S. F. Zornetzer 《Cellular and molecular life sciences : CMLS》1979,35(8):1126-1127
Summary An apparently transient elevation of basal morning (08.00 h) plasma corticosterone levels in male mice was found 48 h after bilateral electrolytic lesions of the brainstem locus coeruleus complex but was not observed 6 weeks after lesioning.Supported by Alfred P. Sloan Foundation research fellowships awarded to W.G. Luttge and S.F. Zornetzer. 相似文献
997.
Riassunto Vengono riportati i dati relativi allo sviluppo in funzione dell'età, della reatività immunologica primaria nel topo con nanismo ereditario preipofisario e nel corrispondente fratello normale. Mentre in quest'ultimo si è notato un graduale incremento della reattività immunitaria di tipo primario soprattutto a partire dalla fine del periodo di allattamento, nel topo nano la reattività immunitaria primaria è rimasta costante nel tempo su bassi livelli anche dopo lo svezzamento. Alla luce dei dati sperimentali riportati viene ipotizzata l'esistenza di un controllo ipofisario della reattività immunitaria primaria. 相似文献
998.
Riassunto Il dodecilsolfato di sodio causa la dissociazione dell'urease (massa molecolare 480,000) in una maniera che dipende fortemente sulla concentrazione relativa dei reagenti. Il prodotto ottenuto con un sufficiente eccesso di detergente ha una massa molecolare di 50,000–60,000.
This work was supported by Grant No. 11,573 and Career Award No. 5K3 GM 13,489 (to G.G.) from the National Institutes of Health, Department of Health, Education and Welfare. 相似文献
This work was supported by Grant No. 11,573 and Career Award No. 5K3 GM 13,489 (to G.G.) from the National Institutes of Health, Department of Health, Education and Welfare. 相似文献
999.
1000.