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411.
Our studies have shown that physical activity (bicycle ergometry) alters the biochemical status of male volunteers. We observed a significant decrease of glucose level and an increase in concentration of magnesium, phosphorus and especially of lactic acid in capillary blood after 5 min of bicycle ergometry start. Creatine phosphokinase activity and the concentration of triglycerides did not differ significantly from the original values. The tendency of changes in the examined parameters was the same in the supine and in the sitting positions. Therefore, biochemical investigations may complement essentially the physiological and neurophysiological tests of human adaptability to physical loads. The method of dry chemistry described in this study can be effectively used in a space flight as the rapid method for evaluation of biochemical parameters of the body.  相似文献   
412.
Conventional influenza vaccines are based on a virus obtained in chicken embryos or its components. The high variability of the surface proteins of influenza virus, hemagglutinin and neuraminidase, requires strain-specific vaccines matching the antigenic specificity of newly emerging virus strains to be developed. A recombinant vaccine based on a highly conservative influenza virus protein M2 fused to a nanosized carrier particle can be an attractive alternative to traditional vaccines. We have constructed a recombinant viral vector based on potato X virus that provides for expression in the Nicotiana benthamiana plants of a hybrid protein M2eHBc consisting of an extracellular domain of influenza virus M2 protein (M2e) fused to hepatitis B core antigen (HBc). This vector was introduced into plant cells by infiltrating leaves with agrobacteria carrying the viral vector. The hybrid protein M2eHBc was synthesized in the infected N. benthamiana plants in an amount reaching 1–2% of the total soluble protein and formed virus-like particles with the M2e peptide presented on the surface. Methods of isolation and purification of M2eHBc particles from plant producers were elaborated. Experiments on mice have shown a high immunogenicity of the plant-produced M2eHBc particles and their protective effect against lethal influenza challenge. The developed transient expression system can be used for production of M2e-based candidate influenza vaccine in plants.  相似文献   
413.
The main physicochemical characteristics of the major isoform of the laccase secreted by the fungus Trametes hirsuta 072 were studied. The enzyme belongs to the group of high redox potential laccases (E T1 0 790 ± 5), and it oxidizes with high efficiency various substrates of phenolic nature. The gene of this isoform was cloned, and its nucleotide sequence was determined. The length of the complete gene is 2134 bp. It comprises 11 exons and 10 introns. Analysis of the amino acid sequence of T. hirsuta 072 laccase demonstrated a high homology to the other laccases secreted by fungi of the genus Trametes.  相似文献   
414.
Beer is a natural product and is a multicomponent system that has both positive and negative consumer properties. Organoleptical off-flavors of beer are difficult to eliminate. Yeasts are the main active component of the system. The relationship between beer quality and yeast usage is well known. New industrial strains for brewery are continuously developed. An industrial yeast Saccharomyces cerevisiae strain was obtained and showed high technological properties, including efficient fermentation, a reduced production of sulfur hydrate, and a high diacetyl reduction rate. The advantages made it possible to develop new brands of beer and nonalcoholic products. The commercial use of the strain was patented. The strain was deposited in the Russian Collection of Industrial Microorganisms.  相似文献   
415.
The correlation between the rates of protein and nucleic acid synthesis and the activity of the key enzymes of glycolysis (hexokinase, phosphofructokinase) and pentose phosphate cycle (glucose-6-phosphate dehydrogenase) in the mitotic cycle of human diploid fibroblasts synchronized by double thymidine block was studied. It was found that the removal of the thymidine block is followed by short-term (presumably, non-specific) simultaneous stimulation of matrix syntheses, as well as by glycolytic and pentose phosphate cycle enzyme syntheses. By the beginning of the S-phase, all the processes appear to be inhibited, followed by gradual activation of glycolysis and pentose phosphate cycle reactions. The implementation of the cell cycle is concomitant with stepwise transitions of protein and hexokinase synthesis rates and ATP content to one of the following levels--basal, intermediate or maximal. Changes in the activity of glucose-6-phosphate dehydrogenase in the course of the cell cycle appear as oscillations, those in phosphofructokinase as alternative states. At stage M, the oscillatory processes are temporarily quenched, whereas the ATP content occupies an intermediate level. In contrast with diploid fibroblasts, in transformed T9 cells the enzyme activity is much higher, and the fluctuations in activity throughout the cell cycle are less noticeable. Presumably, in transformed cells the enzyme activity is at the maximum level and is not prone to effector regulation.  相似文献   
416.
The effect of the physiological concentration of cyclic adenosine-3' ,5'-monophosphate (cAMP) analogues on the proliferation of mouse bone marrow stem hemopoietic cells (CFUs) was examined. The stimulating effect was estimated from the decrease in CFUs expressed in the percentage derived from comparing the number of spleen colonies in the control and experimental groups treated with hydroxyurea 10(-3) M (incubation with hydroxyurea resuted in the cell death in S-phase). Cyclic AMP stimulted the proliferation of CFUs by 60%, while its analogues such as 8-(N-chloroacetylaminoethylamino)-cAMP, 1-(N-chloroacetylaminoethyoxy)-cAMP and 1-(N-(p-fluorosulfonyl)-benzoylaminoethoxy)-cAMP stimulated the proliferation by 39.2%, 32.4% and 21.9%, respectively. Therefore, the synthetic analogues of cAMP were not only far from inhibiting the proliferation of CFUs but, on the contrary, exerted a stimualting effect unlike most antineoplastic alkylating drugs that depress hemopoiesis up to its total aplasia.  相似文献   
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Diacarb or lasix in combination with olivomycin increased the antibiotic antiblastomic activity and toxicity when used for the course treatment of mice with transplanted lymphosarcoma LIO-I. The chemotherapeutic indices of such combinations did not differ from those of olivomycin used alone. Diacarb decreased excretion of olivomycin with the urine in healthy mice, while lasix increased it.  相似文献   
420.
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