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41.
Allele frequencies of the G-->T polymorphism at the regulatory region of the Collal gene in the population of the northwestern Russia (control group) and in osteoporotic patients were estimated by the RFLP method based on PCR-mediated site-directed mutagenesis. Three patient groups with radiologically confirmed osteoporosis were examined. Group 1 consisted of 64 patients with severe osteoporosis complicated by fractures (SO); group 2 included 15 children with idiopathic osteoporosis (IO); group 3 consisted of 98 women with postmenopausal osteoporosis developed at the background of estradiol-deficiency state (PMO). The frequency of functionally defective allele s in the control group was 16.7%. It was statistically different from that in the SO patients (48.4%) (P < 0.01) and in the IO children (40%) (P < 0.01). The frequency of allele s in the PMO patients constituted 23.0% and it was similar to that in the control group (P > 0.05). Analysis of the Collal alleles provides early detection of the individuals with hereditary predisposition to osteoporosis and prophylaxis of the disease at the presymptomatic stage.  相似文献   
42.
Two parts of a geometrical figure are consecutively presented to healthy adult subjects in the left and right visual fields; the subjects have to compare them mentally and to decide whether these parts form a standard figure or not. Correctness of the reaction is controlled by a computer which lights up on the screen the words "good" or "error". The number of correct decisions of this visual-spatial task does not depend on the hemisphere to which information is addressed. The reaction time is substantially shorter if the information comes "directly" to the right hemisphere. Due to better training in the left hemisphere interhemispheric difference in reaction time gradually disappears in repeated tests. Training to mental "constructing" takes place only in the tests following positive feedback stimulus. Analysis of amplitude-temporal parameters of P300 wave shows that at correct decision of the visual-spatial task the level of activation in the right hemisphere is higher than in the left one.  相似文献   
43.
The nuclei of the rat liver, heart, thymus and of the mouse liver isolated in sucrose gradient reveal ATPase sensitive to bicarbonate, sulfite, azide and thiocyanate. The admixture of mitochondria and submitochondrial particles in the nuclear preparation was found negligible, which could not contribute to the anion ATPase in the nuclei. This was demonstrated by the calculation and by the introducing of mitochondria into the nuclear preparations.  相似文献   
44.
Liberation of inorganic ions (potassium and phosphorus), nucleotides and protein from the cells of Candida guilliermondii and rat erythrocytes was studied. It was found that leakage of these components depended on the incubation time, antibiotic dose and amount of the cell material. The potassium ions proved to be most sensitive to the antibiotic: even at low concentrations of roseofungin (2-4 microgram/ml) the amount of the intracellular potassium changed. A decrease in the dry mass and volume concentration in the cells of Candida guilliermondii and lysis in the red blood cells were observed in addition to the leakage of the above intracellular components. The cells of Candida guiliermondii at the beginning of the semilogarithmic growth phase were especially sensitive to roseofungin. The coefficient of roseofungin distribution in the cells of Candida guiliermondü was evaluated. The maximum distribution coefficient was observed at roseofungin concentrations of 40 and 80 microgram/ml for the 4- and 18-hour cultures respectively. Therefore, the effect of roseofungin is characteristic of polyens.  相似文献   
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Uterine leiomyoma (UL) is a benign and most common tumor that affects 20–45% of women of fertile age. In this study, we analyzed the MED12 gene second exon nucleotide sequence from 15 DNA samples extracted from LM of 15 subjects with uterine leiomyoma and 15 DNA samples extracted from peripheral blood leukocytes of the same female subjects. It was shown that somatic mutations in the MED12 gene occur in 73% of cases with deletions of varying sizes and missense mutations being most common at codon 44. Mutations in the MED12 gene could play an indirect role in leiomyoma progression by modifying the activity of other genes that encode proteins involved in growth and tumor progression.  相似文献   
48.
An analysis of literary data concerning the physico-chemical properties of the hydrophobic fragment of bacterial, mitochondrial and chloroplast ATP-synthases has been carried out. The distribution patterns of enzyme subunits and of the whole enzyme complex are reviewed on the basis of amino acid analysis data taking account of physico-chemical characteristics of constituent amino acids. The roles of subunits, their invariant and other amino acids in the hydrophobic fragment function are discussed.  相似文献   
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The activity of ATPase was studied in highly purified rat liver and thymus cell nuclei, HCO3-, CO3(2-) and SO3(2-) stimulated nuclear ATPase in 1.5--2 times. HSO3- did not affect the enzyme activity, and NO3-, J-, ClO4-,F- and SCN- inhibited it. Bicarbonate increased V and decreased Ka for ATP. SCN- inhibited HCO3--ATPase activity non-competitively with respect to HCO3-. Mg2+-ATPase activity did not depend on pH, and HCO3-component of the activity was decreased under alkaline pH. Mg2+, Mn2+ and Co2+ increased the initial ATPase activity and helped its stimulation with HCO3-. Ba2+, Ni2+ and Zn2+ inhibited the ATPase activity, and Ca2+ did not affect it, Nuclear ATPase is sensitive to 2,4-dinitrophenol and DNAase. It is suggested that cell nuclei have their own H+-ATPase differing for some characteristics from mitochondrial H+-ATPase.  相似文献   
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