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961.
Orientation of Giemsa C-bands in Allium cepa was studied in both mitotic and interphase cells. It has been shown that telophase orientation of the chromosome is maintained throughout the interphase and early phophase. It has been assumed that this non-random orientation is due to anchorage of the telomeres with the nuclear membrane. Contrary to earlier observations, 2 by 2 pairing of the telomers could not be traced to this species. 相似文献
962.
C. Gorka 《Cellular and molecular life sciences : CMLS》1977,33(5):659-660
Summary N-acetyl-glucosaminyl transferase in spleen cells of mice infected with M-MTV is enhanced. This increased synthesis of glycoprotein is not due to synthesis of new enzyme. Such a result suggest that the spleen is implicated in the infecting process.
Ce travail fait partie d'une thèse de Doctorat ès-sciences préparée sous la direction de Madame le Docteur Jacqueline Mouriquand. Nous remercions le Professeur Pierre Louisot pour ses conseils fructueux dans la conduite de ce travail. 相似文献
Ce travail fait partie d'une thèse de Doctorat ès-sciences préparée sous la direction de Madame le Docteur Jacqueline Mouriquand. Nous remercions le Professeur Pierre Louisot pour ses conseils fructueux dans la conduite de ce travail. 相似文献
963.
The structure of the combining site of the DNP binding IgA mouse myeloma protein MOPC 315 has been determined by a combination of high resolution nuclear magnetic resonance, electron spin resonance, model building and chemical modifications. This approach yields that general dimensions of the site, its polarity and asymmetry features, the assignment of the DNP-contact residues and their three-dimensional coordinates. 相似文献
964.
A Dautigny I Bernier J Jollès J Colombani P Jollès 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(16):1535-1536
Two serologically active urinary glycoproteins (HLA-A 9 and HLA-B 12) were isolated from urine provided by a patient suffering from tubular proteinuria. Their N-terminal sequences were automatically determined. The latter were identical with the sequence of another urinary glycoprotein (protein HC). The relationship between protein HC and the serological activity is discussed. 相似文献
965.
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
966.
967.
Summary The toxic effect of trimethylphosphate on rat testes was investigated after oral dosing with 250 mg/kg for either 5 days/week for 30 days or 6 days/week for 60 days. After these prolonged treatments azoospermia resulted.Acknowledgments. The authors wish to thank Ms M. Michelles, Ms A. Murray and Ms R. Peake for their technical support. 相似文献
968.
A. Mahmood V. P. S. Chauhan V. Lyall A. K. Sarkar 《Cellular and molecular life sciences : CMLS》1979,35(8):1057-1058
Summary Brush border sucrase and alkaline phosphatase activities are considerably enhanced in the intestine of ascorbic acid deficient guinea-pigs. Similar increase in the uptake of D-glucose and L-alanine also occurs in chronic vitamin C deficiency. However the permeability of D-glucose and L-alanine in the intestine of animals fed with large doses of vitamin C is severely depressed, with a reduction in the levels of sucrase and alkaline phosphatase activities. 相似文献
969.
J. -L. Carpentier P. Gorden P. Freychet A. Le Cam L. Orci 《Cellular and molecular life sciences : CMLS》1979,35(7):904-906
Summary
125I-Insulin initially localizes to the plasma membrane of isolated rat hepatocytes but is subsequently internalized and preferentially associates with lysosomal structures. In the present study, we show that this preferential association to lysosomes occurs in regions of the cell rich in lysosomal and Golgi structures.This work was performed while Dr Gorden was visiting professor of the Institute of Histology and Embryology, University of Geneva, Geneva, Switzerland.This work was supported by grant No. 3.120.77 from Swiss National Science Foundation. We thank M.M. Sidler-Ansermet, O. Jerotic and N. Maalaoui for their valuable help. 相似文献
970.
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