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Antibiotic 308-I isolated from Actinomadura recticatena and the products of its degradation were studied with the methods of electron impact mass spectrometry, chemical ionization with ammonia, field desorption and ion extraction from solution under atmospheric pressure. It was shown that by its composition and structure antibiotic 308-I was identical to antibiotic BBM-928 A.  相似文献   
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With the use of "isotopic method" a study was made of the main parameters of functional activity of serotoninergic elements of hypothalamus--the specific uptake and release of 5-OT. The animals used were sexually mature rats castrated on the first postnatal day. In sexually mature intact males the specific uptake of 3H-5-OT by serotoninergic structures of the anterior hypothalamus was significantly lower than in females. Castration of animals on the first day of life resulted in the increase of specific 5-OT uptake in sexually mature males up to that observed in females. There were no differences between the sexes in the rate of spontaneous release of 5-OT. However, response to K(+)-depolarization in the anterior hypothalamus of intact males was significantly lower than that in females. In the hypothalamus of males castrated neonatally the amplitude of the response to the effect of the depolarizing agent was increase up to the level observed in females. By the results obtained it is indicated that elimination of the effect of male hormones on the first postnatal day results in the increase of 5-OT uptake and release in the hypothalamus of sexually mature rat males.  相似文献   
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Under the conditions of continuous cultivation studies were carried out on a mixed culture (association) with two strains of yeasts: Candida sp., assimilating animal fats, and Candida scottii, assimilating reducing sugars. A complex nutrient medium of wood hydrolysate was used. It was established that in this medium, at a rate of dilution of D = 0.25 h?1, the mixed culture assimilates the fats and the sugars simultaneously. As a result of this the yield of absolutely dry yeasts with regard to the total sum of fats and sugars amounts to 71% in the case of incineration fat and to 82% in the case of technical pork fat. The contents of protein, amino acids, lipids and ashy substances in the yeasts obtained from a medium with fats do not differ substantially from those obtained from the same medium without fats.  相似文献   
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A study was made of protein degradation in rat thymocytes after exposure to ionizing radiation and dexamethasone. The pattern of degradation of 35S-methionine labelled proteins in gamma-irradiated cells and in those incubated in the presence of dexamethasone did not vary from that in control cells. No essential increase was noted in the intracellular protein degradation during interphase death of thymocytes.  相似文献   
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Characteristics of brain associative functions in children of 6 years old with different lability of nervous processes, were compared by methods of conditioning and informational analysis. In children with a low lability, these functions were 1.6 time slower than in other children. Enhanced demands to lability (limitation of time, acceleration of signals presentation) lead to their further slowing and successive inhibition. In children with a high lability, in such conditions an activation of brain associative functions was recorded followed by expressed successive excitation. These differences may be considered as typological. In cases of learned inertness of motor reactions, the characteristics of these functions corresponded to those in children with a high lability of nervous processes.  相似文献   
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