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LN Iashina IP Gileva AB Ryzhikov VA Poryvaeva IA Riazankin TS Bondar'' LG Ovechkina OI Riazankina EG Malygin 《Canadian Metallurgical Quarterly》1997,36(3):36-40
The role and importance of accomplished fertility compared to the total number of pregnancies is discussed from the point of view of working activities, medico-social insurance and amount of risk insurance indemnities of women during different phases of the individual reproductive cycle for the period 1985-1995 in Bulgaria. It is pointed out that the continuing unfavourable demographic tendencies are directly linked with the level of the reproductive function of women. Their individual behaviour in the accomplishment of that function is motivated mainly by changes of economic factors, optimal social insurance indemnities during different phases of the cycle, success in the control of pregnancy complications and especially increasing emotional acceptance of abortions, which sharply exceed births. 相似文献
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Changes in the mu-rhythm power in response to sound (non-specific reactivity, NR) and related with the actual and imaginary movement with the right and left hand in response to sound (specific reactivity, SR) were studied in 38 right-handed patients with subdepressive psychogenic (PD) and endogenous (ED) disorders before and after successful complex treatment (pharmacotherapy and acupuncture) in comparison with 23 healthy subjects. The successful treatment was found to be accompanied by a certain extent of normalization of the disturbed SR which was different in PD and ED. The more complete recovery of the normal reactions in PD was mainly accounted for by the relative decrease in the NR and increase in the SR. The ED treatment predominantly modified the SR. Substantial reorganization of interhemispheric relations during movements in the PD patients resulted in disappearance of the abnormal ipsilateral reactions and transition to the contralateral reactions of the sensorimotor cortex. 相似文献
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A micellar electrokinetic capillary chromatography (MECC) method when compared to free solution capillary electrophoresis (CZE) was shown to offer improved selectivity and resolution for the separation of UV-absorbing components of human urine. Some of the factors affecting MECC separation e.g. methanol concentration, sodium dodecyl sulphate (SDS) concentration, beta-cyclodextrin (beta-CD) concentration, voltage, pH, temperature and electrolyte additives (urea, beta-CD and Brij 35) were optimised using chemometric techniques. Three-level three-factor (3(3)) factorial designs and simplex optimisation were used to achieve optimised conditions with the goal of obtaining the maximum number of peaks in the shortest possible analysis time. Using a TSP CE2000 instrument with detection from 195-300 nm and fitted with a 75 microns x 44 cm (37 cm effective length) fused silica capillary the final optimum conditions were found to be, an electrolyte consisting of 30 mM sodium tetraborate, pH 10, containing 75 mM SDS and 10 mM beta-CD, 15 degrees C, 20 kV, 4 s hydrodynamic injection of filtered urine. These conditions were capable of separating 70 peaks from a normal human urine pool in less than 12 min. The separation of components in urine using the optimised MECC was simpler, more reproducible, faster and gave better resolution than gradient reversed-phase high performance liquid chromatography. 相似文献
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We carried out PCR mutagenesis of the proU promoter of Salmonella typhimurium, in order to identify sequences important for its osmotic control. We obtained five mutations in the -35 element: two decreased the promoter strength, one increased it, and the others had no effect. However, none abolished osmotic control, suggesting that the sequence of the -35 element is not crucial for osmotic control. 相似文献
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