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131.
In the wing disks of Drosophila slowly dividing cells of Minute mutations are progressively eliminated from Minute/Minute+ mosaic compartments by a process known as cell competition. From a study of two different Minutes we show here that the intensity of competition is greater in the more extreme Minute with the slowest rate of cell division. The way in which the more rapidly growing Minute+ clones grow and overcome the surrounding Minute cells is described and cell competition is shown to be a result of local interactions between slow- and faster-growing cells.  相似文献   
132.
The action of cyanogen bromide on the quite insoluble bovine proteolipid apoprotein allowed the determination of four peptide fragments: two of them constituted a 19 amino acid long C-terminal sequence of the apoprotein. Our results were in favour of the existence of only one subunit presenting a molecular weight closely related to 25,000 for which a schematic representation is given.  相似文献   
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Polyamines in rapid growth and cancer.   总被引:79,自引:0,他引:79  
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137.
Two glycoproteins characterized by their serological activities (HLA-A9 and HLA-B12), their isoelectric points and their molecular weights were purified from urine from a patient suffering from tubular proteinuria (cystinosis). Their physicochemical properties as well as an important increase of their specific activities during the different purification steps suggested that they behave as human leucocyte antigens (HLA) which had been excreted into urine. Their amino acid compositions and N-terminal sequences were different to those described for HLA solubilized from cultured human lymphoblast cell lines. The N-terminal sequences of the two serologically active glycoproteins were identical to the N-terminal sequence of another recently purified human urinary glycoprotein called human complex-forming glycoprotein. The relationship between HLA, human complex-forming glycoprotein and the serologically active urinary glycoproteins is discussed.  相似文献   
138.
The secondary structures of cow and sheep kappa-caseins were established according to the predictive rules of Chou and Fasman. The diagrams derived from this treatment allowed us to study the chymosin sensitive bond (milk-clotting process), as well as the glycosylation and phosphorylation sites, found to be situated in beta-turns. Despite a high variability between the primary structures of the COOH-terminal part (caseinoglycopeptide) of cow, sheep, and also other caseins, the secondary structures of the biologically important sites were found to be conserved.  相似文献   
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