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991.
Mileĭkovskiĭ BIu Kiiashchenko LI Titkov ES 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2000,86(6):634-641
Activity of 44 mesencephalic locomotor area's (MLR) units and 38 pontine inhibitory area's (PIA) units was recorded during stimulation of the giganto-cellular reticular nucleus and oral pontine reticular nucleus inducing the hindlimb muscle tone inhibition in decerebrated rats. The muscle tone suppression was always accompanied by a decrease in the MLR and an increase in the PIA unit discharges. Stimulation of the brainstem inhibitory area seems to activate reticulospinal inhibitory system and suppress some MLR units relating to locomotion and muscle tone. 相似文献
992.
Denisenko VIu Kuz'mina TI 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2000,86(4):481-487
The effect of the PKC inhibitor on Ca2+ responses to prolactin in the pig granulosa cells was studied using fluorescent dye and chlortetracycline. The effect was shown to be connected with activation of the PKC. The Ro 31-8220 increased penetration of extracellular calcium and exit of calcium from intracellular stores. The data obtained suggest an involvement of the PKC in changes of calcium contents in the pig granulosa cells activated by prolactin. 相似文献
993.
994.
995.
Rates of carbon dioxide assimilation and methane oxidation were determined in various zones of the Rainbow Hydrothermal Field (36 degrees N) of the Mid-Atlantic Ridge. In the plume above the hydrothermal field, anomalously high methane content was recorded; the microbial population density (up to 10(5) cells/ml) was an order of magnitude higher than the background values; and the CO2 assimilation rate varied from 0.01 to 1.1 micrograms C/(1 day). Based on the data on CO2 assimilation, the production of organic carbon due to bacterial chemosynthesis in the plume was calculated to be 930 kg/day or 340 tons/year (about 29% of the organic carbon production in the photic zone). In the black smoke above active smokers, the microbial population density was as high as 10(6) cells/ml; the rate of CO2 assimilation made up 5-10 micrograms C/(1 day); the methane oxidation rate varied from 0.15 to 12.7 mu/(1 day); and the methane concentration ranged from 1.05 to 70.6 mu/l. In bottom sediments enriched with sulfides, the rate of CO2 assimilation was at least an order of magnitude higher than in oxidized metal-bearing sediments. At the base of an active construction site, whitish sediment was found, which was characterized by a methane high content (92 mu/dm3) and a high rate of oxidation (1.7 mu/(dm3 day)). 相似文献
996.
Vegetative experiments showed that the population density of antiphytopathogenic bacillar species introduced into the rhizosphere of spring wheat seedlings essentially depended on soil temperature and not on the soil moisture content. As a rule, the population of introduced bacilli increased with temperature. Under both low and optimal soil moisture contents, introduced bacilli were efficiently acclimated in the wheat rhizosphere. 相似文献
997.
Nikolaev IuA 《Mikrobiologiia》2000,69(5):597-605
Exchange of information between bacteria via physical signals, referred to as "distant interactions" (DI), is the subject of this review. All cases of DI reported to date are discussed, as well as the history of these studies and the place of DI in bacterial communication. Bacterial DI are a particular case of DI occurring in nature (in plants, animals, and fungi). Along with the chemical signals of intracellular communications, DI play a significant role in the life of microorganisms, especially during critical periods. 相似文献
998.
Parfenova VV Shimaraev MN Kostornova TIa Domysheva VM Levin LA Driukker VV Zhdanov AA Gnatovskiĭ RIu Tsekhanovskiĭ VV Logacheva NF 《Mikrobiologiia》2000,69(3):433-440
The vertical distribution of microorganisms during spring deep-water renewal in Lake Baikal was studied. The downward advection of trophogenic waters was found to create conditions for the extensive growth of microorganisms capable of decomposing and mineralizing organic carbon, nitrogen, and phosphorus in deep water layers. These processes occur annually at spring thermal bars near the underwater slope of Lake Baikal, whereas in its pelagic zone, the deep intrusions of waters rich in organic material are observed only in the years when enhanced deep-water renewal is accompanied by a high spring yield of phytoplankton. 相似文献
999.
Boiandin AN Lobova TI Krylova TIu Kargatova TV Popova LIu Pechurkin NS 《Mikrobiologiia》2000,69(2):243-247
Effect of different concentrations of salts on natural and recombinant strains of Bacillus subtilis and Escherichia coli was studied. The recombinant strain of B. subtilis was found to be more osmotolerant than the wild-type strain of this bacterium, whereas the opposite situation was observed for the recombinant and wild-type strains of E. coli. Some salts exerted a bacteriostatic effect on E. coli and B. subtilis. The adaptive capacity of recombinant strains depended on the number of plasmid copies in the cells. The introduction of recombinant bacteria into model ecosystems resulted in the generation of their variants with increased osmotolerance. 相似文献
1000.