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1.
2.
Effect of psychotropic substances on the development of alcoholic motivation in noninbred white rats
Iu V Burov A V Kampov-Polevo? L N Nikitina 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(3):289-291
The experiments have shown the capacity of antidepressant amitriptylin (0.5 mg/kg, i. p.) and tranquilizer phenazepam (0.1 mg/kg i. p.) to normalize the adaptive behaviour and almost completely prevent the development of alcohol motivation in animals with insufficient adaptive behaviour. It was established that in animals initially rejecting alcohol, chronic treatment with these drugs as well as d-amphetamine promoted alcohol motivation. The results obtained have proved our earlier hypothesis that preclinical search for drugs for the prevention and treatment of early stages of alcoholism is possible only in animals pre-selected according to their inclination to experimental alcoholism. 相似文献
3.
A number of motile strains of Azospirillum brasilense, A. lipoferum, and A. irakense, were found to possess tyrosinase activity both on the surface of and inside the cells. A. brasilense Sp245, Sp7, and A. irakense KBC-1 each possessed two forms of tyrosinase of different molecular masses; A. lipoferum 43, A. lipoferum 59b, and A. irakense KA-3 each had a single tyrosinase form of approximately the same molecular mass; and A. brasilense Sp107 possessed a single form of tyrosinase different from all the other forms. 相似文献
4.
The events that characterize egg formation and maturation inPteris cretica were investigated using transmission electronmicroscopy and electron microscope microprobe analysis. Theydid not differ significantly from those described for sexuallyreproducing ferns. The significance of these findings is discussedin relation to current theories concerning phase change in ferns. Pteris cretica, fern, apogamy, agamospory, transmission electron microscopy, oogenesis 相似文献
5.
L. A. Nikitina 《Development genes and evolution》1978,184(2):109-113
Summary Experiments with oocyte enucleation and transplantation of germinal vesicles show that already at the beginning of the period of rapid growth, the oocyte karyoplasm contains the substances necessary for the appearance in the cytoplasm of the ability to divide. 相似文献
6.
7.
E F Igina K A Tulemisova V S Golubchikov E T Nikitina 《Antibiotiki i khimioterapii͡a》1989,34(1):13-16
Physico-chemical properties of antibiotic complexes formed by various strains of Streptomyces griseoruber: VNIIA 1195, VNIIA 1193-INA 2022/55 and IMiV 1618 were compared. It was shown that the antibiotic complex 1195 differed by the electron absorption spectrum, chromatographic mobility and indicator properties from lateriomycins A and B produced by the type culture of S. griseoruber, Jamaguchi et Saburi, 1955 and strain 70717, as well as from prodigiozin produced by S. griseoruber, VNIIA 1193. By the absorption spectra and chromatographic mobility the components of the antibiotic complex 1195 were identical with cinerubins A and B, pyrromycin and eta- and xi-pyrromycinones included in the composition of antibiotic 1618 produced by S. griseoruber 1618 and differed in their quantitative contents and absence of epsilon-pyrromycinones. 相似文献
8.
A V Kamernitski? I S Levina L E Kulikova V V Korkhov G V Nikitina 《Bioorganicheskaia khimiia》1988,14(6):828-833
The synthesis of 2' beta-methyl-16 alpha,17 alpha-cyclohexanoprogesterone and its MM2 conformational analysis have been performed. The acetyl side chain was shown to have an unusual conformation with the torsion angle C13-C17-C20-O20 being -32.1 degrees. This conformation is by 5.4 kJ.mol-1 more stable than the usual one with the torsion angle 130.3 degrees. 2' beta-Methyl-16 alpha,17 alpha-cyclohexanoprogesterone proved to be inactive as a progestogen (pregnancy maintenance and McPhail tests). The lack of the activity may be due to the additional methyl group in D'-ring causing a change of the conformation of the 17 beta-acetyl side chain, thus hindering the formation of the conformation necessary for binding to the progesterone receptor. 相似文献
9.
The respiration chain in the membranes of whole Actinomyces roseoflavus (var. roseofungini) cells from the parent and secondary cultures is sensitive to KCN, non-sensitive to Triton X-100 treatment removing the antibiotic roseofungin from the cells, and has a very high for the bacteria respiration control. When the cells are in contact with atomic tritium at the temperature of liquid nitrogen, roseofungin is tritiated and binds to A. roseoflavus isolated membranes and whole cells, mostly to those of the parent culture as compared to the secondary culture. A fraction of membranes which lost NADH dehydrogenase in the course++ of purification was isolated from the cells disintegrated in the frozen state. 相似文献
10.
A M Ugolev B Z Zaripov N N Iezuitova A A Gruzdkov I S Rybin M I Voloshenovich A A Nikitina N T Punin MYuTokgaev 《Comparative biochemistry and physiology. A, Comparative physiology》1986,85(4):593-612
Literature data and the results of our investigations using both generally accepted and original perfusion techniques of the isolated loop of the rat small intestine in in vivo experiments are reviewed. Significant differences in the functioning of the small intestine under conditions of acute and chronic experiments are revealed. It has been established that in chronic experiments as compared to acute ones: (a) the absorption of glucose, galactose, fructose and glycine is 2-5 times higher; (b) Kt as well as Jmax values of the transport of these nutrients differ considerably; (c) Na+-independent mechanism of glucose and glycine transport predominates; (d) higher rates of membrane hydrolysis and more effective interactions between enzyme and transport systems of the enterocyte brush border membranes are observed; (e) functional characteristics of the small intestine affected by various experimental factors are more stable. The conclusion is made that it is necessary to revise current views of the scale and regularities of digestive-transport processes in the small intestine under physiological conditions. The importance of the suggested approaches for general and comparative physiology and biochemistry is discussed. 相似文献