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21.
EB Nikol'skaia OV Iagodina BA Grinberg MM Dianova 《Canadian Metallurgical Quarterly》1998,70(3):50-56
Isolation of highly purified and highly molecular monoamine oxidase (MAO) from pig liver mitochondria have been worked out. Specific activity of isolated preparation is 2700 times higher than of original mitochondria homogenate. Enzyme solubilization by digitonin, affinity chromatography purification and ultrafiltration underlie this method. MAO catalytic properties changing during the process of purification by different methods have been investigated. Substrate specificity was studied; kinetic parameters of enzymatic desemination were calculated. 相似文献
22.
AL Evdonin DB Tvorogov NV Tsupkina NN Nikol'ski? ND Medvedeva 《Canadian Metallurgical Quarterly》1998,40(7):648-651
It is known that the growth factor activates appropriate membrane receptors which become starting points of cascades of protein-protein interactions leading to cellular response. Recent data suggest that different signalling pathways may cross-talk during the cellular response. Here we show that phosphoinositide-specific phospholipase C gamma 1, one of the key elements in phosphoinositide pathway of signal transduction, is physically associated with members of the STAT pathway. The precipitation of phospholipase C gamma 1, using polyclonal antibody in A-431 cells, leads to co-immunoprecipitation of STAT1 alpha and STAT1 beta, as well as STAT3. The formation of such complexes was observed in both unstimulated and EGF stimulated cells. The participation of SH3-domains in the formation of such complexes is discussed. 相似文献
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NV Tat'ianko LL Gromashevskaia AD Vovk MG Kasatkina OV Liashok VI Matiash SP Iasinovy? IaN Kovgan 《Canadian Metallurgical Quarterly》1996,(5-6):119-122
In this paper, characterization is given of clinical and biochemical features of VH B course against the background of narcomania. Recordable in such patient populations are high percentage of delta hepatitis (14.2%), unusual severity of the intoxication syndrome, protracted course with exacerbations (12.2%) and recurrences (8%), outcome being a chronic hepatitis (14.2%), slower normalization of biochemical indicators, persistently low ratio of AIAT activity in diluted and whole blood sera. The persistence of viral markers in drug addicts discharged from the hospital (68%) is fraught with danger of spreading viral hepatitis of prophylactic measures are not strictly observed. 相似文献
25.
K. I. Shein I. R. Shein N. I. Medvedeva E. V. Shalaeva M. V. Kuznetsov A. L. Ivanovskii 《The Physics of Metals and Metallography》2006,102(6):604-610
A comparative analysis of the atomic relaxation and electronic structure of niobium (100) and (110) surfaces has been carried out using the VASP-PAW method. The relaxation-induced changes in interlayer spacings of surface layers demonstrate an oscillating behavior but they substantially differ for the two analyzed surfaces; namely for the (110) surface with the closest atomic packing two outermost surface layers are contracted by 4.3% and the relaxation becomes noticeable for three outer layers, while for the more “open” (100) surface these quantities equal 13.1 and six layers, respectively. An analysis of the layer-by-layer distribution of the densities of states, spatial distribution of the charge density, and densities of states at the Fermi level indicates that the most considerable changes near Fermi level take place for (100) surface. 相似文献
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This paper analyzes the cost-effectiveness of the use of renewable energy sources (RES) and peat in production of electric and heat energy in rural places of the country by comparing tariffs (prices) of energy versus total expenditures on generation of electric and heat energy when using RES and peat. The appraisal of a cost-effective scale in application of energy plants working on RES and peat in the rural side in Russia is made by using a model-information set developed at the Energy Institute of the National Research University (Higher School of Economics). It is shown that with the current tariffs, the production by use of RES and peat may become economically effective, which means to achieve 1.8 billion kW/h of electric and 250 million GJ of heat energy per year, and, in the long run, 30 billion kW of electric and up to 400 million GJ per year. In comparison of total expenditures on production of electric and heat energy in rural areas (which are considerably above the established tariffs), it becomes cost effective to produce the electric energy of up to 12 billion kW in the nearest years and up to 80 billion kW in the long run. The need for the governmental policy motivating the projects based on use of RES and peat and the lines of this policy for the rural areas of the country are outlined. 相似文献
29.
E. P. Petrov E. V. Medvedeva 《Journal of Communications Technology and Electronics》2010,55(3):307-315
A method for the synthesis of algorithms for nonlinear filtering of statistically connected (correlated) video sequences of digital halftone images distorted by a white Gaussian noise is proposed. The method is based on the use of hidden Markov chains as a mathematical model for video sequences of digital halftone images, which, in limited observation intervals, can be represented by multidimensional Markov chains. 相似文献
30.
DW Dawson OV Volpert SF Pearce AJ Schneider RL Silverstein J Henkin NP Bouck 《Canadian Metallurgical Quarterly》1999,55(2):332-338
Mal II, a 19-residue peptide derived from the second type 1 properdin-like repeat of the antiangiogenic protein thrombospondin-1 (TSP-1), was inactive in angiogenesis assays. Yet the substitution of any one of three L-amino acids by their D-enantiomers conferred on this peptide a potent antiangiogenic activity approaching that of the intact 450-kDa TSP-1. Substituted peptides inhibited the migration of capillary endothelial cells with an ED50 of 8.5 nM for the D-Ile-15 substitution, 10 nM for the D-Ser-4 substitution, and 0.75 nM for the D-Ser-5 substitution. A peptide with D-Ile at position 15 could be shortened to its last seven amino acids with little loss in activity. Like whole TSP-1, the Mal II D-Ile derivative inhibited a broad range of angiogenic inducers, was selective for endothelial cells, and required CD36 receptor binding for activity. A variety of end modifications further improved peptide potency. An ethylamide-capped heptapeptide was also active systemically in that when injected i.p. it rendered mice unable to mount a corneal angiogenic response, suggesting the potential usefulness of such peptides as antiangiogenic therapeutics. 相似文献