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201.
The polyhedral surface lattice of coated vesicles consists of three-legged hexameric protein complexes called triskelions which constitute the basic assembly unit. The triskelion is a molecular complex of molecular weight 630,000 (Mr 630K) composed of three clathrin heavy chains (subunit 180K) and three light chains (subunits 33K and 36K) (refs 2,3). The presence of additional coated vesicle-specific proteins in the 100-130K and 50-55K range have been reported. We previously described the presence of a cyclic nucleotide- and Ca2+-independent protein kinase activity in coated vesicles which was confirmed by others. This protein kinase specifically phosphorylates the 50K protein (pp50). In this report, we show that the coated vesicle kinase and its 50K protein substrate are part of a stable multimolecular system. In addition we show that the clathrin-light chain complex stimulates the pp50 phosphorylation and only light chains are implicated in this stimulation and that the pp50 phosphorylation does not seem to be affected by the vesicle. 相似文献
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203.
L Zech G Gahrton L Hammarstr?m G Juliusson H Mellstedt K H Robèrt C I Smith 《Nature》1984,308(5962):858-860
Rare cases of chronic lymphocytic leukaemia (CLL) in man stem from the malignant proliferation of T cells. The disease is usually more aggressive clinically than B-cell-derived CLL. Various haematological tumours are associated with specific chromosome aberrations (for example, refs 1, 2). Only limited numbers of T-cell CLL patients have so far been studied cytogenetically and, whereas chromosome 12 seems particularly to be involved in B-cell CLL, several markers have been found in T-cell tumours. Recently, by stimulating malignant clones with different mitogens, novel chromosome abnormalities have been detected in T-cell CLL. Using the same approach for additional cases of T-cell CLL, we now report that the most consistent chromosome change is an inversion of the long arm of chromosome 14, inv(14)(q11 q32), in four of five patients. Another remarkable chromosome aberration is trisomy for the long arm of chromosome 8, found in three of five patients. 相似文献
204.
Summary The ascorbic acid content of brown adipose tissue increased 62% when rats underwent cold acclimation; however, the increase was 126% when rats living in the cold were fed a basal diet supplemented with 2% ascorbic acid. These findings suggest a role for ascorbic acid in this tissue during nonshivering thermogenesis.Bureau of Nutritional Sciences, publication No. 113. 相似文献
205.
206.
H. Schmitt Hélène Schmitt Simone Fénard 《Cellular and molecular life sciences : CMLS》1973,29(10):1247-1249
Résumé La destruction extensive de l'aire dépressive bulbaire provoque chez le chat une chute de la pression artérielle, du rythme cardiaque et une diminution de l'activité électrique du nerf splanchnique. La clonidine ne provoque alors qu'une augmentation de la pression artérielle, sans hypotension secondaire, ni diminution des potentiels splanchniques. La perte des influences sympatho-inhibitrices de la clonidine est encore plus nette chez le chien, car la destruction extensive de cette aire ne provoque qu'une diminution légère de la pression artérielle et de l'activité électrique du nerf splanchnique. 相似文献
207.
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C Hélène T Montenay-Garestier 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,288(1):143-146
Mixed aggregates of tryptophan and 1, N6-ethenoadenosine (epsilon Ado) are formed in frozen aqueous solutions at 77 K. In these aggregates one observes a quenching of tryptophan fluorescence by small amounts of epsilon Ado together with a sensitized fluorescence of epsilon Ado. About 70 tryptophan molecules are able to transfer their energy to one epsilon Ado molecule. 相似文献
209.
210.
J. L. Andrieu M. Ollagnier M. Lièvre I. Hugueny R. Tédone G. Faucon 《Cellular and molecular life sciences : CMLS》1979,35(7):892-893
Summary Carbocromen prevents to some extent, particularly in subendocardial layer, carbohydrate cardiac metabolism alterations induced by the ischemia obtained by intermittent occlusion of left coronary artery.Acknowledgments. Financial support from the U.E.R. of biologie Humaine is gratefully acknowledged. 相似文献