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Vladimir D. Savitsky Ludmila G. Bezus'ko Natalia G. Butich Zoya M. Tsymbaliuk Olena V. Savitska Timur V. Bezus'ko 《Aerobiologia》1996,12(3):209-211
This article presents the results of aeropalynological observations in Kiev, carried out with a gravimetric method, during
January–October, 1994. The six most abundant pollen types were: Betulaceae (21%), Chenopodiaceae/Amaranthaceae (10%), Ambrosia
(10%), Artemisia (9%) Pinaceae (8%) and Poaceae (6%). Seasonal fluctuations of the atmospheric presence of tree/shurb and
herb/grass pollen during the period March–September, 1993 and 1994, are also shown. 相似文献
283.
Measuring the physiological heterogeneity of natural and industrial microbial populations is essential to studying, modelling and monitoring of microbial populations. It was discovered that populations of Escherichia coli and Bacillus megaterium growing in medium with ethanol as an external source of energy have two actively respiring but physiologically different subpopulations. Cells of one subpopulation have negligibly low alcohol dehydrogenase (ADH) activity (ADH-L cells) and cells of the other have high ADH activity (ADH-H cells). The subpopulation of ADH-H bacterial cells was measured using 10 min incubations of cells in a 1% solution of allyl alcohol for fast selective killing of cells with high activity of ADH and flow cytometry detection of dead cells after this incubation. The content of ADH-H cells during exponential phase of batch culture varied from 9 % to 90 % and lowered to zero for a few hours during starvation of the population. ADH-L cells are actively respiring cells and not depolarized cells. The simultaneous presence of ADH-L and ADH-H cells growing in the medium with ethanol can be explained by the fact that ADH-H cells oxidize actively external ethanol whereas ADH-L cells oxidize only intracellular storage carbohydrates. The method for enumeration of cells with high ADH activity can be used to monitor the heterogeneity of bacterial populations consuming ethanol as a sole source of carbon and energy. 相似文献
284.
Kostyantyn V Dmytruk Oleh V Smutok Olena B Ryabova Galyna Z Gayda Volodymyr A Sibirny Wolfgang Schuhmann Mykhailo V Gonchar Andriy A Sibirny 《BMC biotechnology》2007,7(1):33
Background
Accurate, rapid, and economic on-line analysis of ethanol is very desirable. However, available biosensors achieve saturation at very low ethanol concentrations and thus demand the time and labour consuming procedure of sample dilution. 相似文献285.
Olena Jacenko 《BioEssays : news and reviews in molecular, cellular and developmental biology》1995,17(4):277-281
Development of gene transfer systems provides a key tool for understanding gene function. Exciting and often unexpected consequences from embryo manipulations are yielding insights into molecular mechanisms underlying development under normal and pathogenic states, and are providing animal models for diseases. Contributing to this progress is the elegant work on c-fos(1), where Wagner and coworkers identify this proto-oncogene as a primary factor which directs cell differentiation along the osteoclast/macrophage lineages, and thus regulates bone remodeling. Their studies support a link between skeletogenesis, marrow formation and hematopoiesis, and may help to delineate mechanisms underlying the oncogenic transformation of skeletal and hematopoietic cells. 相似文献