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71.
S. G. Prokushkin T. N. Bugaenko N. D. Sorokin L. N. Kaverzina O. A. Zyryanova 《Biology Bulletin》2004,31(1):42-50
It is shown that larch of the prefire generation is the main edificator at the early stages of progressive successions in burned-out areas. Its environment-forming effect manifests itself most strongly in the phytogenic field of living trees, where edaphic conditions similar to those in primary larch forests are formed within ten years after the fire. This is accompanied by an increase in the numbers of microorganisms utilizing organic and mineral nitrogen, as well as in the rate of nitrogen mineralization in plant microgroups of this zone. Hence, living trees remaining in a burned-out area promote restoration of the initial edaphic conditions. 相似文献
72.
Studying morphological changes of the myocardium in the organic, cellular and subcellular levels of experimental animals (dogs) has shown that standard physical load on tradmill band graded only by external parameters of work (time of running, its speed etc.) causes different changes in different animals. In contrast to it, the method of individually graded physical load proposed by the author (1970, 1972) considers the depth of myocardium responses, the degree of its morphofunctional changes corresponding to certain stages of changes in the parameters of cardio-vascular activity and respiratory system. Using the relationship of pulse rate and frequency of respiration as a diagnostic test made it possible to establish 6 stages of myocardium responses to physical load. Each of these stages has a complex of morpho-functional changes in the myocardium and corresponds to certain adaptive shifts on the organism level. On these foundations one can prognoze the depth of morphological changes in the myocardium basing upon diagnostic tests. So, the proposed experimental model of individual selection of the value of physical load according to responses of the organism rather than to external parameters of work as well as the established principle of the stage character of adaptive responses may be used in the practice of investigators for directed influence on the myocardium to form its certain qualities. 相似文献
73.
Dimitry Y. Sorokin Martijn Diender Alexander Y. Merkel Michel Koenen Nicole J. Bale Martin Pabst Jaap S. Sinninghe Damsté Diana Z. Sousa 《Environmental microbiology》2021,23(7):3460-3476
An anaerobic enrichment with CO from sediments of hypersaline soda lakes resulted in a methane-forming binary culture, whereby CO was utilized by a bacterium and not the methanogenic partner. The bacterial isolate ANCO1 forms a deep-branching phylogenetic lineage at the level of a new family within the class ‘Natranaerobiia’. It is an extreme haloalkaliphilic and moderate thermophilic acetogen utilizing CO, formate, pyruvate and lactate as electron donors and thiosulfate, nitrate (reduced to ammonia) and fumarate as electron acceptors. The genome of ANCO1 encodes a full Wood–Ljungdahl pathway allowing for CO oxidation and acetogenic conversion of pyruvate. A locus encoding Nap nitrate reductase/NrfA ammonifying nitrite reductase is also present. Thiosulfate respiration is encoded by a Phs/Psr-like operon. The organism obviously relies on Na-based bioenergetics, since the genome encodes for the Na+-Rnf complex, Na+-F1F0 ATPase and Na+-translocating decarboxylase. Glycine betaine serves as a compatible solute. ANCO1 has an unusual membrane polar lipid composition dominated by diethers, more common among archaea, probably a result of adaptation to multiple extremophilic conditions. Overall, ANCO1 represents a unique example of a triple extremophilic CO-oxidizing anaerobe and is classified as a novel genus and species Natranaerofaba carboxydovora in a novel family Natranaerofabacea. 相似文献
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77.
A R Antonov Iu V Nacharov A S Sorokin G S Iakobson 《Biulleten' eksperimental'no? biologii i meditsiny》1992,114(7):27-29
It is shown that acute alcoholic intoxication causes essential changes of aldosterone content and balance of electrolytes in blood plasma of Wistar rat males. The SPL test revealed the inadequate reaction in the mineral-corticoid function of the adrenal glands in the rats with acute alcoholic intoxication. The method of the free choice of the load by the experimental rats is the most optimal way to assess. The rats with acute alcoholic intoxication displayed smaller tolerance to physical load. 相似文献
78.
V. N. Danilevich V. V. Sorokin Ya. P. Moiseev S. V. Sizova 《Doklady. Biochemistry and biophysics》2018,479(1):118-122
The patterns of formation of RNA nanoparticles (NPs) during thermal cycling of bacterial total tRNA in the presence of cations Ca2+, Mn2+, Ni2+, Zn2+, Co2+, and Cu2+ were studied. The optimal conditions for the production of NPs were found, and it was revealed that their size depends on the ratio of the concentrations of Me2+ and tRNA. The concentration of reagents for obtaining NPs of small size (from 5 to 100 nm) was selected. It was shown that tRNA-based nanoparticles can comprise short (20–50 nt) ribooligonucleotides, including aptamers and siRNAs. The stability of NPs during storage in buffer solutions of various composition was studied. It was found that the initial suspensions of NPs are quite stable, but they are rapidly destroyed in PBS buffer (pH 7.4). A simple and effective stabilizer (polyarginine) was found, the additives of which ensure the preservation of nanoparticles in PBS buffer for more than 5 h. Nanoparticles modified with the stabilizer are resistant to blood serum nucleases and can be used for transfection. 相似文献
79.
Kalenov Sergei V. Gordienko Mariia G. Murzina Ekaterina D. Poberezhniy Daniil Y. Baurin Dmitry V. Suzina Natalia E. Morozov Alexander N. Yakubovich Liubov M. Belov Alexey A. Panfilov Victor I. Yarovaya Oksana V. Il’in Michail M. Sorokin Vladimir V. Skladnev Dmitry A. 《Extremophiles : life under extreme conditions》2018,22(3):511-523
Extremophiles - Spray drying is appropriate for the preservation of halophilic microorganisms due to the nature of these microorganisms, as they survive in adverse environmental conditions by being... 相似文献
80.
Anna Mamaeva Zorigto Namsaraev Yevhen Maltsev Evgeniy Gusev Maxim Kulikovskiy Maria Petrushkina Alla Filimonova Boris Sorokin Nikita Zotko Vladimir Vinokurov Dmitry Kopitsyn Daria Petrova Andrei Novikov Denis Kuzmin 《Journal of applied phycology》2018,30(4):2237-2246
Manipulation of the nutrient concentration is an inexpensive and efficient method for increasing lipid and TAG accumulation in algal cells. However, high volumetric production requires finding a proper balance between the decrease of biomass production and the increase in the total lipid content. We isolated a strain of green microalga Bracteacoccus bullatus and increased its lipid content from 17 to 59% of biomass dry weight by manipulating of nitrogen and phosphorus content in the medium. The 10-fold reduction of the nitrogen and phosphorus concentration in the medium was the most efficient method of the lipid induction compared to nutrient deplete and high nutrient conditions. The oleic (48–64% mass of total fatty acids) and linoleic (14–24% mass of total fatty acids) acids dominated in the fatty acid profile, thus making this strain a suitable candidate for biodiesel production. 相似文献