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981.
An anti-ischemic effect of the delta-sleep-inducing peptide (DSIP) was found in rats. The DSIP effect was more obvious than that of the MK-801. The data obtained is discussed considering a possible use of the DSIP for brain stroke prophylaxis.  相似文献   
982.
The data obtained show that, at the initial stages of hypothermia, a decrease in the oxygen consumption and carbon dioxide production, cardiac output, and heart rate occurred in accordance with the temperature coefficient. Suppression of the tissue gas exchange was unrelated to disorders in the lung gas exchange but determined rather by a progressing weakening of heart activity, decrease in the cardiac output, and increase in the general vascular peripheral resistance.  相似文献   
983.
The results of the first methodical investigation into the aerobic methanotrophic communities inhabiting the bottom sediments of Lake Baikal are reported. Use of the radioisotopic method revealed methane consumption in 12 10- to 50-cm-long sediment cores. The maximum methane consumption rates (495-737 microl/(dm3 day) were recorded in sediments in the regions of hydrothermal vents and oil and gas occurrence. Methane consumption was most active in the surface layers of the sediments (0-4 cm); it decreased with the sediment depth and became negligible or absent at depths below 20 cm. The number of methanotrophic bacteria usually ranged from 100 to 1000 cells/cm3 of sediment and reached 1 million cells/cm3 in the regions of oil and gas occurrence. The 17 enrichment cultures obtained were represented mainly by morphotype II methanotrophs. Phylogenetic analysis of the enrichment cultures in terms of the amino acid sequence of the alpha subunit of the membrane-bound methane monooxygenase revealed the predominance of methanotrophs of the genus Methylocystis. The results obtained suggest the presence of an active aerobic methanotrophic community in Lake Baikal.  相似文献   
984.
985.
Six patients in the state of remission after the first episode ofjuvenile schizophrenia and seven sex- and age-matched mentally healthy subjects were examined by fMRI and ERP methods. The auditory oddball paradigm was applied. Differences in P300 parameters didn't reach the level of significance, however, a significantly higher hemodynamic response to target stimuli was found in patients bilaterally in the supramarginal gyrus and in the right medial frontal gyrus, which points to pathology of these brain areas in supporting of auditory selective attention.  相似文献   
986.
Ivanitskiĭ GR 《Biofizika》1999,44(5):773-795
By the example of the formation of dissipative patterns in Belousov-Zhabotinsky reactions and in population waves of mobile microorganisms, an attempt was made to analyze the development of the "autowave conception" in the last ten years. New results obtained at the Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, were demonstrated. The place of the "autowave conception" among other methods of studying nonlinear cooperative bioprocesses that form the basis of synergism is shown. The review was prepared on the occasion of the 275th anniversary of the Russian Academy of Sciences and the 2nd Biophysical Meeting of Russia.  相似文献   
987.
Associative cyanobacteria were isolated from the rhizoplane and velamen of the aerial roots of the epiphytic orchids Acampe papillosa, Phalaenopsis amabilis, and Dendrobium moschatum and from the substrate roots of Acampe papillosa and Dendrobium moschatum. Cyanobacteria were isolated on complete and nitrogen-free variants of BG-11 medium. On all media and in all samples, cyanobacteria of the genus Nostoc predominated. Nostoc, Anabaena, and Calothrix were isolated from the surface of the A. papillosa aerial roots, whereas the isolates from the substrate roots were Nostoc, Oscillatoria, and representatives of the LPP-group (Lyngbia, Phormidium, and Plectonema, incapable of nitrogen fixation). On the D. moschatum substrate roots, Nostoc and LPP-group representatives were also found, as well as Fischerella. On the aerial roots of P. amabilis and D. phalaenopsis grown in a greenhouse simulating the climate of moist tropical forest, cyanobacteria were represented by Nostoc, LPP-group, and Scytonema in the D. phalaenopsis and by Nostoc, Scytonema, Calothrix, Spirulina, Oscillatoria, and the LPP-group in P. amabilis. For D. moschatum, the spectra of cyanobacteria populating the substrate root zhizophane and the substrate (pine bark) were compared. In the parenchyma of the aerial roots of P. amabilis, fungal hyphae and/or their half-degraded remains were detected, which testifies to the presence of mycorrhizal fungi this plant. This phenomenon is attributed to the presence of a sheath formed by cyanobacteria and serving as a substrate for fungi.  相似文献   
988.
Angiogenesis is a complicated process, which is regulated by numerous cytokines and growth factors. Besides, the interaction of endothelial cells with extracellular matrix components, with other cell types and with each other is essential for the formation on new blood vessels. The initiation, continuation and completion of angiogenesis depend on the balance of pro- and antiangiogenic factors in the endothelium microenvironment. Factors that influence endothelial cell proliferation are necessary for vascular development and their normal functioning. The influence of new pharmaceutical agents on angiogenesis is commonly evaluated by results of in vivo assays, i.e. chick chorioallantoic membrane and rabbit cornea assays. However, reported results are not always objective. So, the aim of our study was to elaborate methods of estimation of endothelial cell proliferation as one of important stages of angiogenesis.  相似文献   
989.
The modem literature data were observed, which dedicated to the study of neurobiological studies of gamma-rhythm mechanisms, providing the cognitive functions in hymans: state of readiness and attention, providing of sensory indentification, perception and memorizations, decision-making, management of psychomotor response, emotional and semantic processing of an information. It was shown that synchronous gamma-activity is at integrative activity, which in deteriorated in pathology of thinking. Literature data were analysed concerning ot the changes of gamma-activity (spontaneous, evoked, provoked by photostimulation etc.) in a number of neuropsychiatric disorders: epilepsy, schizophrenia, Alzheimer's disease, attention deficit hyperactivity disorder, stroke etc. as compared with norm. The data observed testify to high significance of gamma-activity in the brain functioning.  相似文献   
990.
Comparative antimicrobial activity of lactoferrins from various sources (native lactoferrin from Laprot, human hololactoferrin, recombinant human lactoferrin isolated from the cultural medium of permissive cell culture transfected using pseudoadenovirus nanostructure with the human lactoferrin gene, and native bovine lactoferrin) was studied to prove the possibility of their use for development of antimicrobial drugs. It was shown that all the substances were active against the Bacillus standard strains. The antibacterial activity was almost independent of the degree of saturation the lactoferrin molecules with Fe3+. The native human lactoferrin was more active than hololactoferrin against Candida when evaluated by the minimum inhibitory concentration (MIC). Fe(3+)-Non aturated recombinant human lactoferrin demonstrated the antimicrobial activity (by MIC) similar to that of the native human lactoferrin. The results showed that native and recombinant human lactoferrins might be used for the development of intravenous and intracavitary dosage forms, while the native bovine lactoferrin could be useful in development of oral drugs.  相似文献   
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