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41.
The effect of superlow concentrations of KCl and CaCl2 solutions, obtained by diluting starting 1 M solutions of these salts 10(9)-10(15) times, on the fluctuations of pass band coefficients of water was studied. It was found that these solutions are substantially distinguished from bidistilled water by a high intensity of fluctuations of spectra in the infrared region. It was also shown that higher concentrations of solutions of these salts (at dilutions less than 10(8) times) have no strong and specific effect on fluctuations of the infrared spectrum: the intensity of fluctuations of the infrared spectra of these solutions practically coincides with that of control water. Possible reasons for this effect are discussed.  相似文献   
42.
The studies of 137Cs and 90Sr accumulation characteristics by birch wood (Betula pendula Roth.) growing in different edaphic conditions. Were conducted was stated that the increase in soil fertility from trophotops A to D results in 5-fold 137Cs transfer factor decrease and 2-fold decrease of 90Sr. Soil humidity increase for each grade of trophic net results happens the increase of 137Cs transfer factors to wood and decrease for 90Sr. Total activity of 37Cs and 90Sr in birch wood plantation depends on plantation productivity and on radionuclide transfer factors depending on different plantation conditions. In the most prevailing edaphotops (B2, B3, C2 and C3) birch wood accumulates 0.6-1.2% of 137Cs and 13-19% of 90Sr from total activity of radionuclides in biogeocenosis.  相似文献   
43.
The analysis of plutonium production factors has been carried out by using two methodical approaches: assessment of chromosomal aberrations level in routine and G-banded metaphases and molecular-cytogenetic investigation of aneugenic/clastogenic damages in cytokinesis-block binuclear lymphocytes by FISH with centromere specific DNA probes. The obtaining data point out for the first time about both aneugenic and clastogenic influences of incorporated 239Pu with activity range from 0.37 to 6.95 kBq. Correlation analysis of chromosome aberrations with cytome abnormalities allowed finding significant connection between number parameters of metaphase and interphase approaches. The results of this study support the suggestion that aberrant chromosomes are involved preferable in aneugenic events. The FISH technique in binucleated cytokinesis-blocked lymphocytes allows extending of detecting spectrum of chromosome damages and glance of aneugenic mechanisms. Correlations between metaphase and interphase-FISH results point out a high sensitivity of FISH cytome assay, which could be used as an independent test for detection both clastogenic and aneugenic environment influences.  相似文献   
44.
In experiments in mice, hamsters and dogs therapeutic radioprotective efficiency and toxicity of new water-soluble copolymer were studied. It was found that at intramuscular injection of the copolymer to dogs in a dose of 5 mg/kg 24 h after irradiation with a dose of 3.30 Gy (LD85/45) it showed pronounced therapeutic effect (68.1%). In mice and hamsters, the effect was less pronounced: 42-21% after irradiation with a dose of 8.0 Gy. The copolymer is low toxic substance and according to the State standards of Russian Federation belongs to the fourth class (harmless).  相似文献   
45.
The heart contractility and changes of lipid composition of isolated rat heart (n = 26) under total ischemia and ischemia-reperfusion was studied. The effect of N-stearoyl-ethanolamine under these conditions was investigated. N-stearoyl-ethanolamine leads to remodelling of fatty acyl chain composition of myocardial phospholipids: to drastic fall of polyunsaturated fatty acyl chains (18:2w6, 20:3w6, 20:4w6, 22:5w3, 22:5w6, 22:6w3 and 22:6w6) and enhancement of 18:0. This can be caused by N-stearoyl-ethanolamine-induced suppression of polyunsaturated fatty acids synthesis. Naturally occurring minor lipids--N-acyl phosphatidylethanolamine and its derivative N-acylethanolamine were detected in isolated rat heart under ischemia-reperfusion. It is notable that approximately 12% of total N-acylethanolamines were composed by anandamide. Treatment of N-acyl phosphatidylethanolamine by phospholipase D with subsequent fatty acyl chain analysis demonstrates that fatty acid composition of both N-acyl chains of N-acyl phosphatidylethanolamine and free N-acylethanolamine are similar and their main fatty acyl chains are 16:0, 18:0 and 20:4w6. It was shown that exogenous N-stearoyl-ethanolamine did not alter the levels of endogenous N-acyl phosphatidylethanolamine and N-acylethanolamine, but caused the decrease of lyso-phosphatidylcholine and phosphatidylglycerol levels. The rate of heart contractility and heart relaxation was found to increase during the early period of reperfusion. N-stearoyl-ethanolamine prevents this alteration and exerts a negative inotropic effect. It is concluded that membrane protective properties of N-stearoyl-ethanolamine at least partly depend on its ability to inhibit decrease amount of arachidonic and docosahexaenoic acids, to modulate the fatty acyl chains of cardiac phospholipids and to decrease the level of lyso-phosphatidylcholine.  相似文献   
46.
The authors state their opinion on this problem by analyzing their 5-year use of their programme specially developed for detection of breast disease, mainly cancer, among females visiting specialized rooms of non-mammological profiles (gastroenterology, endocrinology, rheumatology, pulmonology, neurology, cardiology, hematology, nephrology, etc.) in the consulting polyclinics of regional (territorial) hospitals and large city hospital-polyclinic complexes. In this period, mammographic studies were made in 9169 women included into a breast cancer-risk group. Of them 1370 young female patients with well-developed glandular tissue that makes mammographic diagnosis of presumed masses difficult underwent breast ultrasonography. Abnormalities were found in 6092 (66.44%) patients. Breast cancer and nodal benign masses (including cysts and fibroadenomas) were detected in 278 (3.03%) and 669 (7.30%) women, respectively. The detection rates of unpalpable breast malignant and benign masses carcinomas were 0.4 and 3.03%, respectively. The findings allow the authors to recommend their proposed screening programme for wide use in large regional (territoreal), city, and town polyclinic complexes.  相似文献   
47.
The review describes several modules of the GeneExpress integrated computer system concerning the regulation of gene expression in eukaryotes. Approaches to the presentation of experimental data in databases are considered. The employment of GeneExpress in computer analysis and modeling of the organization and function of genetic systems is illustrated with examples. GeneExpress is available at http://wwwmgs.bionet.nsc.ru/mgs/gnw/.  相似文献   
48.
Urokinase activates adhesion of monocytic U937 cells to fibrinogen-coated surface. This effect is due to urokinase proteolytic activity and does not depend on the urokinase binding to its receptor.  相似文献   
49.
The structural peculiarities of the most widespread oxysterols, the products of oxidative transformations of cholesterol are discussed. The transformations proceed with the participation of enzymatic systems of the body or as a result of various nonenzymatic reactions. The pathways of their formation from cholesterol are also considered. The role of oxysterols in the maintenance of cholesterol homeostasis and in the development of atherosclerosis is reviewed. The possibility of using oxysterols as markers of pathological processes is demonstrated.  相似文献   
50.
A comparative study of the conformation dynamics of a series of heptapeptides: the human alpha-fetoprotein fragment LDSYQCT and its seven analogues has been conducted. The effect of the dielectric constant of medium on the dynamics of heptapeptide conformation is considered. It is shown that electrostatic interactions have a marked effect on several accessible conformations and the dynamics of the behavior of amino acid residues.  相似文献   
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