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The iodine accumulation by strains of microscopic fungi Penecillium chrysogenum isolated from soddy-middle podzolic soils of Kirov region has been studied. It has been shown that fungi are able to accumulate from 5,0 X 10(-5) to 10,2% of iodine depending upon the medium iodine content and the degree of the organisms' tolerance to its high concentrations.  相似文献   
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Experimental pollinosis was modelled on guinea pigs. The animals were placed in a cell in which an allergen-water-dialyzed extract of ambrosia pollen was dispersed by means of coaxial pulveriser. Homocytotropic antibodies serving as indices of animal sensitization to the specific allergen formed in guinea pigs as a result of aerosol sensitization. Sensitization of the animals to the ambrosia allergen was accompanied by an increase of sensitivity of the broncho-pulmonary apparatus and was characterized by the bronchospastic reaction in resolving inhalation or inrtavenous injection of a specific allergen.  相似文献   
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Many studies suggest that MPF activation depends on protein phosphorylation or that MPF is itself a protein kinase. In the present report, cyclic variations of MPF activity have been correlated in vivo with changes in the extent of protein phosphorylation or in vitro with changes of a major protein kinase during the first cell cycles of fertilized starfish eggs. This cycling protein kinase neither requires cAMP nor Ca2+. Neither colchicine nor aphidicoline, which inhibits cleavage and chromosome replication respectively, was found to suppress the synchronous and cyclic variations of both MPF and protein kinase activities. Protein synthesis was found to be required for both MPF and protein kinase activities to reappear after their simultaneous drop at the time of mitotic or meiotic cleavages. Production of either MPF or protein kinase activities is not the immediate result of protein synthesis since there is a delay at each cell cycle between the time when protein synthesis is required and the time when both MPF and protein kinase activities are produced. This suggests that both MPF and protein kinase activities might involve some post-translational modification of a precursor protein synthesized during the preceeding cell cycle.  相似文献   
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The liver lesion in the CBA mice has been induced by administration of one of three agents five times every day; gamma-globulin fraction of antihepatocytotoxic serum in doses of 4.8 and 7.7 mg of protein per 100 g of body mass; gamma-globulin fraction of normal rabbit serum and bovine serum albumin in a dose of 4.8 mg of protein; three- four- or five-fold introduction of carbon tetrachloride in a dose of 0.5 ml per 100 g of body mass with oil (1:1) each three days; calibrated stenosis of the portal vein was produced. The total number of hemopoietic stem cells in the bone marrow was estimated by the colony-forming unit/spleen assay. Histological analysis of the colony-forming units was applied. The liver lesion was accompanied by a decrease in the ratio of the erythroid/granulocytic colonies.  相似文献   
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中国平脉树螽属五新种记述:直翅目:螽斯科:树螽亚科   总被引:2,自引:0,他引:2  
本文报道中国平脉树螽属5个新种。每个新种皆有详细的形态描述和形态特征图。所有模式标本存于北京农业大学昆虫标本室。  相似文献   
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Prevost, I. and Le Page–Degivry, M. Th. 1985. Changesin absicisic acid content in axis and cotyledons of developingPhaseolus vulgaris embryos and their physiological consequences.—J.exp. Bot. 36: 1900–1905.Changes in abscisic acid (ABA)content with time were measured in embryonic axes and in cotyledonsof Phaseolus vulgaris embryos using a radio–immunoassay.During embryogenesis, a similar pattern was observed in bothtissues: ABA increased to a maximum 29 d after an thesis, followedby a decrease as the seed matured. The level of ABA in the cotyledonswas always much higher than that in the axes. In in vitro cultures,the duration of the lag phase before germination of isolatedembryonic axes increased with ABA content. The presence of cotyledonsalways lengthened the lag phase; longer lag phases were associatedwith greater concentrations of ABA in the cotyledons. Moreoverthe presence of cotyledons stimulated the growth of seedlings. Key words: ABA distribution, embryo maturation, axis and embryo germinability  相似文献   
10.
Some data are reported on pathoanatomical changes, a status of the microcirculatory channel and the coagulogram of animals affected by high doses of ionizing radiation. The signs of disseminated intravascular blood coagulation have been revealed. The authors discuss the relationship between clinical manifestations with coagulopathy development and circulatory disturbances during intestinal and cerebral forms of acute radiation sickness.  相似文献   
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