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71.
It was shown in rats that stress is accompanied by a decrease in osmotic resistance and antioxidant protection of erythrocytes and an increase in their volume and diameter; cholesterol esters were reduced, the amounts of malone dialdehyde, cholesterol, sphingomyelin, and phospholipid lysofractions were increased. Comparative data on the membrane protecting activity of extracts of Laminaria japonica and Eleutherococcus senticosus are presented. Administration of these extracts caused the normalization of the parameters of erythrocytes in rats.  相似文献   
72.
A novel simple synthetic protocol for the preparation of both (2S,4R)- and (2S,4S)-FGlu, applying Michael addition of methyl α-fluoroacrylate to a NiII complex of glycine Schiff base with BPB, was elaborated. In addition, same reaction of mentioned complex with ethyl α-bromoacrylate leads to the NiII complex of the Schiff base of BPB with (2S,4R)-4-bromo-glutamic acid monoester, that can be transformed into the corresponding complexes of 1-aminocyclopropane-1,2-dicarboxylic acid. The decomposition of the diastereoisomerically pure complexes leads to corresponding enantiomerically enriched (ee > 98%) amino acids.  相似文献   
73.
In the process of biooxidation at 39°C in a continuous mode of the gold-arsenic concentrate from the Olympiadinskoe deposit, which was pretreated by chemical leaching with ferric ions, by a microbial association from the BIO department reactors of the Polyus gold mining company, a bacterial culture designated as strain HT-4 was isolated. The bacterium was a spore-forming rod 0.5–0.6 × 1.4–2.0 μm with a flagellum. The optimal temperature for growth and Fe2+ oxidation was 55°C. The strain grew in the pH range from 1.21 to 2.10 with the optimum at pH 1.6. The organism was incapable of lithotrophic and organotrophic growth. It grew mixotrophically by Fe2+ oxidation in the presence of 0.02% yeast extract. The DNA G+C base content was 48.6 mol %. Based on comparative phylogenetic analysis of 1472-bp nucleotide sequences of 16S rRNA genes, strain HT-4 was classified as Sulfobacillus thermosulfidooxidans. Analysis by pulse-field gel electrophoresis revealed a unique profile of the NotI fragments of the chromosomal DNA. These results demonstrate the strain and species diversity of sulfobacilli in microbial associations involved in biooxidation of concentrates in different technological conditions. The strain “S. olympiadicus S-5” dominated in the process of biooxidation of original concentrate not treated with ferric iron, while S. thermosulfidooxidans HT-4 was predominant in biooxidation of the chemically leached concentrate.  相似文献   
74.
By means of determination analysis, optimum values of phytoplankton biomass and its divisions are calculated. These values provide development of high biomass of such primary consumers as zooplankters. It is shown that representatives of Rotatoria have higher levels of optimum biomass than Crustacea. In the Kara region it is possible to ascertain the increase of such levels for Cladocera in comparison with Copepoda. The prediction of zooplankton communities’ development is carried out using values of optimum biomass of phytoplankton. Accuracy of the forecast in the Azov area is highest, i.e., quantitative requirements of zooplankton for fodder phytoplankton here are poorly subject to variability in time.  相似文献   
75.
One hundred and seven healthy full-term newborns were examined in this study. The cardiointer-valogram (CIG) was continuously recorded on the fifth to seventh day of life. An electropolygram (EPG) was recorded in 14 newborns along with the CIG and included the electroencephalogram, electrooculogram, electrocardiogram, and pneumogram. The functional state of the infants was continuously monitored, and calm or active wakefulness and active or calm sleep were distinguished using common criteria. Quantitative analysis of the sleep EPG was used to differentiate sleep phases by a standard method. The CIG was analyzed during orthodox (OS) and paradoxical (PS) sleep, and three different CIG types were distinguished by visual assessment and differential criteria established previously. The three types of CIG considerably differed in the structure and power spectrum of slow oscillations of R-R intervals, especially in the range from 0.04 to 0.15 Hz. The type I CIG was recorded during OS. At the end of this phase, the variability range increased while the amplitude of the mode and the tension index were reduced, indicating the type II CIG, with a duration of 3–4 min. All three CIG types were observed during PS; the type III CIG dominated, accounting for 58.3 ± 4.6% of the phase duration. A relationship was found between the CIG types and the cyclic organization of sleep, pointing to a difference in mechanisms regulating the heart rate in different functional states of the central nervous system in newborns.Translated from Fiziologiya Cheloveka, Vol. 31, No. 2, 2005, pp. 90–95.Original Russian Text Copyright © 2005 by Evsyukova, Kondrateva.  相似文献   
76.
Enzyme preparations were isolated from the culture liquid of five mutant strains of the cellulase producer Penicillium verruculosum. The hydrolytic activities of these preparations against unbleached eucalypt cellulose was compared to that of commercial preparations of Trichoderma reesei (T. longibrachiatum). In the majority of cases, P. verruculosum enzymes provided higher yields of reducing sugars (RSs) and glucose. A correlation was found between the yield of RSs and the avicelase activity of the preparations in the reaction mixture.Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 2, 2005, pp. 210–212.Original Russian Text Copyright © 2005 by Skomarovsky, Gusakov, Okunev, Soloveva, Bubnova, Kondrateva, Sinitsyn.  相似文献   
77.
We conducted a lifetime study of the content of oxidized and methylated guanine in the urine of intact and irradiated mice. For statistical processing of the results, we used the trial period method created by A.A. Konradov, which was unpublished during the author’s lifetime. We prove that there are oscillating components in the age dependence of the concentration of oxidized and methylated guanine in mice urine. For intact animals, a 7-month oscillation period is the most probable (p = 0.001). For irradiated mice, a disruption in the seasonal oscillation rhythm in the concentration of oxidized and methylated guanine in urine was noted, which is peculiar to radiation-accelerated aging.  相似文献   
78.
The interaction of endotoxins--lipopolysaccharides (LPS) different in degree of the O-specific chain polymerization--with 20- and 130-kD chitosan was studied using the competitive binding of LPS with the complex of chitosan-anionic dye (tropaeolin 000-2) and the direct binding of (125)I-labeled LPS with chitosan immobilized on Sepharose 4B. The interaction of 20-kD chitosan with LPS was non-cooperative, and immobilization of the polycation on Sepharose resulted in its binding to (125)I-labeled LPS with a positive cooperativity. The interaction of LPS possessing a long O-specific chain with 130-kD chitosan was characterized by negative cooperativity. Binding constants of LPS with the polycation and the number of binding sites per amino group of chitosan were determined. The interaction affinity and stoichiometry of the LPS-chitosan complexes significantly depend on the LPS structure and concentration in the reaction mixture. The increase in the length of carbohydrate chains of LPS results in increase in the binding constants and decrease in the bound endotoxin amount.  相似文献   
79.
The morphological diversity of antennal sensory organs in larvae of Galeruca sp. (Coleoptera, Chrysomelidae), Limnephilus centralis (Trichoptera, Limnephilidae), and Eristalis tenax (Diptera, Syrphidae) was studied. A sensory cone on the antenna was found in all the species studied. The cuticular part of the antennal cone is pierced with pores. No significant differences in the shape of the antennal cone were revealed. The innervation patterns of the antennal cone varied from single cells in the leaf beetle larvae to groups of cells with a common scolopoid sheath in the fly larvae. The cone combines several types of sensilla that perform mechanoreceptor, olfactory, and gustatory functions. The morphology and ultrastructural organization of the antennal cone in relation to the heterogeneity of the larval habitats are described.  相似文献   
80.
Original materials on the fauna of the northern macroslope of the Sette-Daban Mountain Ridge are presented. Birds and mammals population in different habitats in the basin of the Allakh-Yun River are characterized.  相似文献   
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