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Genes rplJ, coding for ribosomal protein L10 of Salmonella typhimurium and Klebsiella pneumoniae, have been cloned on pUC plasmid. The resultant multicopy recombinant plasmids were detrimental for the growth of normal JM101 E. coli host cells and harmless for the mutant JF3029 host. This negative effect is the evidence for the ability of heterologous L10 proteins to regulate expression of rplJL genes in E. coli. Nucleotide sequence was determined completely for S. typhimurium rplJL' DNA portion and partially for rplJL' genes of K. pneumoniae. According to the nucleotide sequence data obtained three amino acid substitutions differ L10 proteins of S. typhimurium and E. coli and the long range, providing for the coupled translations of L10 and L7/L12 cistrons in E. coli mRNA is also valid for S. typhimurium and K. pneumoniae.  相似文献   
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The epidemiological effectiveness of dipyridamol, an interferon-inducing agent used for the prevention of influenza and viral acute respiratory diseases, was tested in 4 epidemiological trials, 3 of them carried out as double blind trials. Observations were made in groups of adults (a research institute, a factory) and children (a kindergarten, a school), comprising 1040 subjects in the test groups and 771 subjects in the control groups. The drug was used during the whole epidemic period (January--March 1983) according to the following schedule: 1 oral administration in 8 days, in doses of 8 mg for adults, 50 mg for schoolchildren and 24 mg for children in the kindergarten. The epidemiological effectiveness of the drug was evaluated by comparing the total morbidity rates in influenza and acute respiratory diseases in the test and control groups. The results of 4 trials showed a pronounced epidemiological effectiveness of dipyridamol. The values of the epidemiological effectiveness index of the drug were 2.38 in the kindergarten, 1.55 at the school, 7.42 at the factory and 2.16 at the research institute. The results of the study of dipyridamol suggest that further investigations should be made with a view to use it for the mass prevention of influenza and acute respiratory diseases.  相似文献   
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On electrophoretic separation of lactate dehydrogenase (LDH, EC 1.1.1.27) isoenzymes in tissue extracts of heart, kidney, skeletal muscle, and liver in minks, ferrets, polar foxes, foxes, raccoon dogs, nutria, and chinchillas, species peculiarities were revealed in ratios of the agar gel electrophoretic fractions. Thus, a higher relative content of the enzyme A-subunits in the LDH spectra of liver and skeletal muscles was found in semiaquatic animals, minks and nutrias, in comparison with terrestrial animals, polar foxes, ferrets, and chinchillas. In raccoon dogs and chinchillas, a high relative content of the enzyme B-subunits was revealed in these organs. All these data are an example of biochemical specialization of functions at the molecular level to ecological environmental conditions.__________Translated from Zhurnal Evolyutsionnoi Biokhimii i Fiziologii, Vol. 41, No. 3, 2005, pp. 240–246.Original Russian Text Copyright © 2005 by Tyutyunnik, Kozhevnikova, Unzhakov, Meldo.  相似文献   
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The effect of simultaneous injections of apomorphine and l-DOPA on stereotypy, aggressiveness, on the exploratory motor activity, the threshold of emotional reactivity and aggressiveness elicited by painful electrical stimulation was studied in experiments on male albino rats. When injected separately, in control experiments, both compounds had similar effects on the exploratory-motor activity and the emotional behaviour, but when injected simultaneously in various doses a distinct antagonism between l-DOPA and apomorphine, according to all the behaviour tests, was noted (a decrease of sterotypy, aggressiveness and emotional reactivity). Against the background of l-DOPA apomorphine (5 mg/kg) increased the dopamine content in the forebrain and in the diencephalon even more. It is suggested that the increased level of the functionally active mediator suppressed the activity of postsynaptic receptors sensitive to it.  相似文献   
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