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OV Sivochalova 《Canadian Metallurgical Quarterly》1995,(9):1-4
Modern demographic situation stressed the problems of human reproductive health associated with industrial medical topics. The article suggests to regard a family (child and two parents) as a unit under study in industrial medicine. This methodic approach should work in scientific programs reviewing influence of industrial ecology and environmental factors on reproductivity. The authors suggest elaboration of universal strategy for ecologic and epidemiologic studies to form a scientific branch "Epidemiology of reproductive health" and to elaborate methods for better health management during the present demographic crisis. 相似文献
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KS Makarova IuI Vul'f IA Seledtsov VA Ratner 《Canadian Metallurgical Quarterly》1995,31(12):1614-1629
Transposons of gypsy group are assigned to LTR-containing retrotransposons present in the genomes of invertebrates, fungi, and plants. In this work, a theoretical analysis of the potential products of ORFs of these retrotranposons was conducted. Alignments were obtained and trees of similarity were constructed for domains of the POL region. On the basis of the obtained data, two hypothetically monophyletic subgroups of transposons were distinguished within the framework of the gypsy group, settling the genomes of taxonomically related organisms (the subgroup of "true" gypsy of insects and the subgroup of gypsy-like transposons of plants and fungi). A number of peculiarities of the topology of these trees hypothetically indicate cases of genetic conversion and recombination of domains accompanying the evolution of this group. The amino acid substitution fixation rate was evaluated on the basis of comparison of sequences of the protein products of ORFs. Estimates of the time of divergence of subgroups of gypsy-group transposons are significantly less than estimates of the times of divergence of their host species. One explanation for this discrepancy might be the hypothesis of settlement by transposons of the genomes of isolated host species. 相似文献
14.
NS Kislitsina BA Katsnel'son LI Privalova OV Driakhlova 《Canadian Metallurgical Quarterly》1995,(10):31-34
The authors proved that animals having higher natural antioxidant activity and lower intensity of lipid peroxidation are more resistant to fibrogenic effects of quartz. The peritoneal macrophages obtained from those animals show higher resistance to quartz exposure "in vitro". Parameters characterizing antioxidant system should be included into a group of indexes describing propensity to silicosis. 相似文献
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LIa Iukel'son OV Krasil'nikov EE Gussakovski? BA Tashmukhamedov 《Canadian Metallurgical Quarterly》1977,22(5):806-810
It has been stated that boiled for three hours haemocytocardiotoxin (HT) from cobra poison loses "direct" hemolytic activity and is unable to potentiate a haemolytic effect of phospholipase A. Surface activity of HT does not change. It is shown that in the course of heat denaturation the aggregation of toxin molecules to dimers and trimers takes place and electrophoretic mobility is decreased. The fluorescence of HT tyroxin residues supported the fact of its irreversible heat denaturation. 相似文献
16.
The problem of constructing linear regression models in the presence of errors in input and output data is considered. A statistical
test for detecting measurement errors in input data is proposed that does not require a preliminary consistent estimation
of the coefficients under the assumption of the presence of errors. The test is validated by Monte-Carlo statistical simulation. 相似文献
17.
M. N. Palatnikov I. V. Biryukova S. M. Masloboeva O. V. Makarova O. E. Kravchenko A. A. Yanichev N. V. Sidorov 《Inorganic Materials》2013,49(7):715-720
This paper reports a comparative study of the homogeneity of LiNbO3〈Mg〉 (≥5 mol % Mg) crystals grown from a charge synthesized using Nb2O5〈Mg〉 prepared through homogeneous magnesium doping of a reextract in the Nb2O5 extraction step, and LiNbO3〈Mg〉 crystals prepared through direct doping of a growth charge. The LiNbO3〈Mg〉 crystals were characterized by optical microscopy and Raman spectroscopy. The results demonstrate that the LiNbO3〈Mg〉 crystals prepared using homogeneous doping are more structurally uniform. 相似文献
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