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781.
Somatic chromosomes of four common bats of Allahabad 总被引:1,自引:0,他引:1
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784.
R. K. Bhatnagar K. G. Mukerji K. K. Maggon T. A. Venkitasubramanian 《Applied microbiology and biotechnology》1979,7(1):99-102
Summary The effect of lithium on growth and aflatoxin production in chemically defined medium was studied on three aflatoxigenic strains of Asperigillus flavus group. The three strains used differed in their aflatoxin producing capacities. The possible mechanism of lithium induced stimulation of aflatoxin biosynthesis is discussed. 相似文献
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786.
A protease activity associated with the micrococcal nuclease-solubilized chromatin from mouse seminiferous tubules has been characterized. Proteolysis of histone H1 and core histones is stimulated in the presence of 3 M urea. The pH optimum of this protease is between pH 8 and 9, and the activity is not inhibited by trypsin or chymotrypsin-active site inhibitors. Leupeptin is an effective inhibitor of the protease at low concentrations. Soluble chromatin from neonatal and prepubertal mice lacks this proteolytic activity until three to four weeks after birth. That the protease activity is localized in the dinucleosomes and higher oligomers but is lacking in mononucleosome populations suggests its association with the linker DNA. Rat testis-soluble chromatin apparently lacks such a protease activity. The developmental expression of this protease and its in situ localization are consistent with a role in histone displacement during mouse spermiogenesis. 相似文献
787.
A K Ganguly S S Sathiamoorthy O P Bhatnagar 《Quarterly journal of experimental physiology and cognate medical sciences》1978,63(1):89-92
Gastric mucosal mast cell population was studied following sub-diaphragmatic vagotomy in albino rats, 6 and 12 h after pylorus ligation. Sub-diaphragmatic vagotomy significantly increased the gastric mucosal mast cell population in both 6 and 12 h groups, the increase being more in the latter. The results suggest that the vagal impulses act on the gastric mucosal mast cells causing their degranulation. Following vagotomy the contents stay bound within the mast cells. Increase in mast cell population with the longer experimental situation was possibly due to the continuation of normal turnover of the mast cells in the gastric mucosa. The present study, however, does not lead to a conclusion that the vagal influence on mast cell population is similar throughout the gastro-intestinal tract. 相似文献
788.
Using radioimmunoassay and 3 region specific antisera toward bovine neurotensin (NT), the NT-like peptides in chicken have been shown to differ from NT but to strongly resemble its COOH-terminal region. Three substances were identified, one of which resembled NT biologically and appeared to share 7 or 8 of its COOH-terminal residues. The two other peptides were smaller than NT but seemed to possess 4–6 residue homologies with it. Tissue distribution studies indicated that the chicken pancreas and thymus had unusually high levels of this material (>200 fold that in rat) and that the 3 substances were distributed differently in tissues. Chromatographic studies showed that the peptides obtained from brain, intestine, thymus, and pancreas were similar. These results, demonstrating evolutionary conservation of the COOH-terminal region of NT, are in keeping with the known importance of this region for biological activity. These findings also suggest the existence of an NT-family of peptides serving multiple biological roles. 相似文献
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