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281.
Résumé Le rétablissement de la réactivité du noyau oculo-moteur et du gyrus marginal pendant le sommeil a été mesuré chez le chat non-immobilisé. Comme paramètre de ce rétablissement on a utilisé le rapport de l'amplitude du second potentiel à celle du premier potentiel induit par stimulation du noyau vestibulaire médian, du colliculus supérieur et du noyau réticulaire oral du pont. On a constaté que le rétablissement de la réactivité à la stimulation du noyau vestibulaire médian diminue pendant le sommeil, ce qui n'est pas le cas des réponses à la stimulation du colliculus supérieur et du noyau réticulaire pontique, ni celui des réponses obtenues pendant l'éveil. On en a conclu que le rôle du noyau vestibulaire médian et du colliculus supérieur dans le mécanisme responsable des mouvements oculaires rapides pendant le sommeil est différent.
This work was aided by a grant-in-aid from the Indian Council of Medical Research, New Delhi. 相似文献
This work was aided by a grant-in-aid from the Indian Council of Medical Research, New Delhi. 相似文献
282.
Summary Each of the 2 groups of medial neurosecretory cells has 10–12 A and 2–3 B-cells. Each pars intercerebralis lateralis has 3–4 B-cells only. The 2 nervi corporis cardiaci I (NccI) join with the lateral wall of the aorta and Ncc II terminate in corpora cardiaca (Cc). Only 1 corpus allatum is present. The paraldehyde fuchsin positive neurosecretory material is stored in the dorsal aorta and not in the Cc which indicates the neurohaemal nature of the aorta.We are grateful to Prof. U.S. Srivastava for providing laboratory facilities and S.C.S.T. Uttar Pradesh for financial assistance. 相似文献
283.
284.
Summary Drought resistant cv. C-214 ofCicer arietinum L. showed higher accumulation of alanine, threonine, glutamine, -alanine, arginine, amino butyric acid, valine, leucine, phenylalanine than the susceptible cv. G130 under water stress. 相似文献
285.
A. Giridhari Singh Meera Tewari V. K. Madan C. P. Tewari 《Cellular and molecular life sciences : CMLS》1976,32(6):694-695
Summary Guanine deaminase solubilized from the light mitochondrial fraction of rat liver was activated by lecithin. The activation was proportional to the concentration of lecithin taken in the system. A ratio of 11 between the two constituents (protein and lecithin) was at least necessary for complete precipitation.Acknowledgment. The authors are grateful to Professor P.S.Krishnan, University of Calicut, Calicut, Kerala, for his interest. 相似文献
286.
D. V. Singh R. L. Campbell Y. N. Lin N. D. Nigro 《Cellular and molecular life sciences : CMLS》1977,33(11):1516-1518
Summary Treatment with propylthiouracil (PTU) resulted in a significant decrease in azoxymethane-induced intestinal tumors, total concentration of fecal bile acid as well as the fecal neutral steroids, cholesterol and coprostanol. Thus, a hypothyroid state induced by PTU treatment may affect intestinal carcinogenesis in this animal model by lowering the concentration of fecal bile acids and neutral steroids.We would like to acknowledge the excellent technical assistance of Dale Miller, Kenneth Kohn, Mathew McGee and Michael McLaughlin. We also wish to thank Dr M. S. Pak for the histological work, and Ms Mary Acree and Ms Kathleen Smith for the excellent secretarial assistance. Supported by the Maltida R. Wilson Fund. 相似文献
287.
众所周知,农产品交易的顺利进行需要一个有效可靠而的市场买卖信息系统,它能为农户提供关于到货、当前价格、大致价格趋势、交易价格等新鲜的市场信息。但要建立这样一个信息系统,需要在村级水平上建立信息站点,并对市场信息进行实时更新,然后提供给农户。 相似文献
288.
S. N. Singh A. K. Srivastava S. C. Gupta R. K. Chatterjee K. C. Saxena 《Cellular and molecular life sciences : CMLS》1990,46(7):742-744
Summary DuringAcanthocheilonema viteae infection, the specific activity of -glutamyltranspeptidase (-GT) increased in peritoneal exudate cells and bone marrow and decreased in lymphnodes ofMastomys natalensis throughout the course of infection. However, though there was an increase in specific activity of -GT in thymus and spleen during the prepatent phase ofA. viteae infection, the level either returned to normal or decreased during the latent phase of infection. A close correlation was observed between the host's immune status duringA. viteae infection and the level of -GT in lymphoid tissues.Communication No. 4535 from Central Drug Research Institute, Lucknow. 相似文献
289.
Models of circadian genetic oscillators involving interlinked feedback processes in molecular level genetic networks in Drosophila
melanogaster and Neurospora crassa are studied, and mechanisms whereby synchronization can arise in an assembly of cells are
examined. The individual subcellular circadian oscillatory processes are stochastic in nature due to the small numbers of
molecules that are involved, and are subject to large fluctuations. The authors investigate and present the simulations of
the stochastic dynamics of ensembles of clock-regulating proteins in different nuclei that communicate via ancillary small
molecules, environmental parameters, additive cellular noise, or through diffusive processes. The results show that the emergence
of collective oscillations is a macroscopic observable which has its origins in the microscopic coupling between distinct
cellular oscillators. 相似文献
290.
Isatin has been found to inhibit rat testicular alkaline phosphatase (EC 3.1.3.1). That the inhibition is non-competitive as well as non-allosteric is evident from a) the hyperbolic curve relating inhibition as a function of inhibitor concentration; b) the small change in enthalpy, free energy and entropy; c) the number of isatin molecules associating with 1 molecule of the enzyme (n=1.29); and, d) the decrease in the values of both Km and Vmax in the presence of isatin. 相似文献