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891.
Anna Sterniczuk Elbieta I. Waajtys-Rode Anna B. Wojtczak 《Cell biochemistry and function》1991,9(1):13-21
The flux through branched-chain alpha-ketoacid dehydrogenase and the activity of the branched-chain alpha-ketoacid dehydrogenase complex were measured in hepatocytes isolated from fed, starved and alloxan diabetic rats. The highest rate of branched-chain alpha-ketoacid oxidation was found in hepatocytes isolated from starved rats, slightly lower in those from fed rats, and significantly lower in diabetic hepatocytes. The amount of the active form of branched-chain alpha-ketoacid dehydrogenase was only slightly diminished in diabetic hepatocytes, whereas the flux through the dehydrogenase was inversely correlated with the rate of endogenous ketogenesis. The same was observed in hepatocytes isolated from starved rats when branched-chain alpha-ketoacid oxidation was measured in the presence of added oleate. In both cases the diminished flux through the dehydrogenase, restored by a short preincubation of hepatocytes with insulin, was paralleled by a decrease of fatty acid-derived ketogenesis. The significance of these findings is discussed in relation to the role of insulin in branched-chain alpha-ketoacid oxidation in liver of diabetic rats. 相似文献
892.
893.
894.
The development of tumorigenic conditions in the carcinogen-exposed rat colon was studied using selected morphological, histochemical, immunohistochemical and biochemical methods of analysis. Rats were treated with two carcinogens: 1,2-dimethylhydrazine and N-methyl-N'-nitro-N-nitrosoguanidine alone or with deoxycholic acid as a tumor promoter. It was found that 3 months after treatment of animals with the carcinogens the following changes were developed in colonic tissue: infiltration of lymphocytes in the mucous membrane, high increase in mitotic index among epithelial cells, negative reactions of colonic cells for neutral mucopolysaccharides and sulfomucins and positive reactions to carboxyl groups, nonsulfated acid mucosubstances and tissue polypeptide antigens. An increase in the activity of ornithine decarboxylase in colonic tissue was developed within the same time period and has been seen only in those tissues which were characterized by the development of precancerous conditions. Individual variations were observed in the manifestation of the studied parameters in rat neoplastic colonic tissues. It is suggested that these differences reflect an individual sensitivity of animals to carcinogens and the magnitude of the dysplastic processes induced in the colon. 相似文献
895.
896.
Changes in composition of both total aerobes and anaerobes of rat intestinal microflora do not appear to affect the metabolism of taurolithocholic acid. 相似文献
897.
E I Williams 《BMJ (Clinical research ed.)》1984,288(6411):119-121
A study was carried out in two large urban practices to determine the number of patients aged over 75 years who had had no contact with the primary care team during one year and to examine their medical and social characteristics. Although their general health was considered to be good, over half needed treatment or other action and half had no identifiable career. 相似文献
898.
B I Marakusha V G Petrovskaia K I Volkovo? 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1986,(10):3-8
Mutants, resistant to neamine and spectinomycin, have been isolated from S. typhimurium and S. dublin highly virulent strains. The neamine-resistant mutants can be divided into 3 classes in accordance with their sensitivity to streptomycin: sensitive, resistant to low and high concentrations of this antibiotic. The transduction analysis with the use of bacteriophage P 22 has revealed that the spectinomycin-resistant mutations under study are spc A mutations, while the mutations leading to resistance to neamine in class Near Strr 500 are nea B mutations. The mutation leading to resistance to spectinomycin (spc A) has been found to produce no changes in the virulence of salmonellae in the intraperitoneal infection of mice. The mutations leading to resistance to neamine and streptomycin (nea B and str A) have been found to decrease virulence. 相似文献
899.
900.
A I Vengerovski? V S Chuchalin O V Paul's A S Saratikov 《Biulleten' eksperimental'no? biologii i meditsiny》1987,103(4):430-432
The hepatoprotective agents, silybinin and essentiale, were shown to prevent the development of lipid metabolism disturbances in the liver and serum of rats with CCl4-hepatitis. Slow accumulation of triglycerides, lysophosphatidylcholine and cardiolipin was observed in animals treated with these drugs, while phosphatidylcholine liver level remained high. Silybinin and essentiale inhibited the production of lipid hydroperoxide, Shiff basis, malonic dialdehyde, intensified the function of tissue antioxidants, activated liver beta-hydroxybutyrate dehydrogenase and depressed the activation of serum phospholipase A. 相似文献