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171.
Pseudozyma fusiformata BKM Y-2821--a producer of antifungal glycolipid]   总被引:2,自引:0,他引:2  
The yeast Pseudozyma fusiformata (the order Ustilaginales) produces an extracellular low-molecular-weight protease-resistant thermostable fungicide, which was active against more than 80% of the 280 yeast and yeastlike species tested. The fungicide, extracted with methanol and purified by column and thin-layer chromatography, was found to consist of glucose and saturated fatty acids.  相似文献   
172.
The peripheral blood and central lymph of rats under experimental myocardial infarction was studied by means of light microscopy and electric conductivity measurement. Both hypertensive rats and animals 3 days after myocardial infarction had similar quantity of neutrophils in peripheral blood. Lymph cells count of hypertensive rats by middle lymphocytes is similar to the animals 1 day after myocardial infarction. The correlation between lymph and blood electric conductivity and its cell composition was noted.  相似文献   
173.
NO-dependent mechanisms of adaptation to hypoxia.   总被引:3,自引:0,他引:3  
In studying NO-dependent mechanisms of resistance to hypoxia, it was shown that (1) acute hypoxia induces NO overproduction in brain and leaves unaffected NO production in liver of rats; (2) adaptation to hypoxia decreases NO production in liver and brain; and (3) adaptation to hypoxia prevents NO overproduction in brain and potentiates NO synthesis in liver in acute hypoxia. Dinitrosyl iron complex (DNIC, 200 microg/kg, single dose, iv), a NO donor, decreases the resistance of animals to acute hypoxia by 30%. Nomega-nitro-L-arginine (L-NNA, 50 mg/kg, single dose, ip), a NO synthase inhibitor, and diethyl dithiocarbamate (DETC, 200 mg/kg, single dose, iv), a NO trap, increases this parameter 1.3 and 2 times, respectively. Adaptation to hypoxia developed against a background of accumulation of heat shock protein HSP70 in liver and brain. A course of DNIC reproduced the antihypoxic effect of adaptation. A course of L-NNA during adaptation hampered both accumulation of HSP70 and development of the antihypoxic effect. Therefore, NO and the NO-dependent activation of HSP70 synthesis play important roles in adaptation to hypoxia.  相似文献   
174.
Neurons of the Wulst region, an analog of the mammalian visual cortex, were studied in Golgi-impregnated preparations of brain of non-precocial 1-day old nestlings of the pied flycatcher Ficedula hypoleuca. At this age, vision does not function in nestlings, their behavior is provided by an acoustic analyzer. Two populations of nerve cells, large and small juvenile neurons, were differentiated at visual examination. The comparative morphometry has shown these groups to differ significantly from each other by most studied parameters: the area of the profile field of their soma, the total length of dendrites, branching of the cell, the number of the maximal branching foci, the character of distribution of dendrite free endings in three concentric zones of the cell dendritic field. The distribution of dendrites in the dendritic neuron field was similar in the both groups of neurons. An increased density of dendrites was observed from the side of the afferent input. At the same time, study of orientation of the longest dendrite has shown it to be located parallel to the plane of the afferent input practically in all cells of the both groups. It is suggested that such orientation of the longest dendrite broadens the area of cell contacts, which is necessary for search for the maximal number of afferents. The predominant orientation of dendrites in the direction to the afferent input forms foundation for establishing a more extended zone of contacts with growing visual afferents.  相似文献   
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A concept of the divertor and the technology for organizing the edge plasma in a fusion neutron source based on a spherical tokamak (FNS-ST) are described. The experimental data on the characteristics of the peripheral plasma in modern tokamaks are extrapolated to the FNS-ST conditions with the help of semi-analytical models. The effects depending on the magnetic configuration and on the geometry and materials of the divertor and the first-wall elements are considered. Possible designs of the FNS-ST divertor and the first wall are described. Using an original model, it is shown that the maximum density of the heat flux at the divertor plates in a double-null magnetic configuration does not exceed 5?C6 MW/m2, which complies with modern engineering capabilities. Methods for further improvement of the FNS-ST divertor concept are analyzed.  相似文献   
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