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Lebedeva EV Alawi M Fiencke C Namsaraev B Bock E Spieck E 《FEMS microbiology ecology》2005,54(2):297-306
Samples from three hot springs (Alla, Seya and Garga) located in the northeastern part of Baikal rift zone (Buryat Republic, Russia) were screened for the presence of thermophilic nitrifying bacteria. Enrichment cultures were obtained solely from the Garga spring characterized by slightly alkaline water (pH 7.9) and an outlet temperature of 75 degrees C. The enrichment cultures of the ammonia- and nitrite oxidizers grew at temperature ranges of 27-55 and 40-60 degrees C, respectively. The temperature optimum was approximately 50 degrees C for both groups and thus they can be designated as moderate thermophiles. Ammonia oxidizers were identified with classical and immunological techniques. Representatives of the genus Nitrosomonas and Nitrosospira-like bacteria with characteristic vibroid morphology were detected. The latter were characterized by an enlarged periplasmic space, which has not been previously observed in ammonia oxidizers. Electron microscopy, denaturing gradient gel electrophoresis analyses and partial 16S rRNA gene sequencing provided evidence that the nitrite oxidizers were members of the genus Nitrospira. 相似文献
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The research of distribution of blood group ABO, Rhesus, Lewis, Secretor, C5+-component of choline esterase and the ability to taste PTC among Moscow population patients suffering from duodenal ulcer is carried out in comparison with the control. Statistically authentic association of the disease with 0(I) blood group, unsecretor and the association of joint signs (coefficients of association are 1.32, 2.17 and 2.62 respectively) is found. Authenticity of relation with disease is not proved during the investigation of other signs. The values of risk to fall ill for the patients possessing and not possessing the signs of duodenal ulcer are obtained (concerning separate factors and joint factors). It is established that the combination of 0(I) blood group and unsecretor increases the risk of the diseases in 2.4 times as compared with the patients possessing A, B, AB blood groups and secretors. 相似文献
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M. V. Nabozhenko N. V. Lebedeva S. V. Nabozhenko V. D. Lebedev 《Entomological Review》2016,96(1):101-113
The taxocene of lichen-feeding darkling beetles from the tribe Helopini is studied in the steppes of the south of Rostov Province. The species of lichens grazed on by the representatives of this tribe are identified for the first time and dependence of circadian activity and spatial distribution of adults on temperature and air humidity is shown. Global warming and human activities may have caused degradation of steppe lichen communities that formed the dietary base for the lichen-feeding darkling beetles in natural ecosystems. As a result, 3 out of 4 beetle species completely left steppe biotopes for tree shelterbelts. This caused a change in the trophic relationships (transition from epigeic to epiphytic lichens) and in the spatial distribution of darkling beetles, promoted the establishment of competitive interactions, and increased the duration of circadian and seasonal activity due to the lengthening of the periods with optimum temperature and air humidity for each species. 相似文献
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A S Fokin N T Shutova L N Lebedeva E D Klimenko 《Biulleten' eksperimental'no? biologii i meditsiny》1975,79(5):28-31
In a chronic experiment (up to 6 years) on dogs (13) a protracted functional overstrain of the CNS was associated with an additional action changing the hormonal background (castration and mercasolyl injection). A steady hypercholesteremia, atherosclerotic changes in different intraorganic arteries, particularly in the myocardium, developed in dogs; dystrophic processes occurred in the parenchyma of various organs. An important role of functional overstrain of the CNS as one of the leading factors of the "risk" determining the development of disturbances of the regulation of lipid metabolism and formation of the atherosclerotic process in the vessels was demonstrated. 相似文献