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941.
942.
943.
The clinical manifestations of clonorchiasis were studied in 190 patients in the Amur River region. The severity of the disease correlated with the excretion rates of Clonorchis eggs. The peculiarity of the region is a rather low egg excretion; 66.8% of patients excreted as many as 100 eggs/g, 27.3%, up to 1000 eggs/g. Most examinees (94.3%) suffered from chronic gastroduodenitis and functional disorders of the biliary system.  相似文献   
944.
In the nearly 15-month mission aboard MIR the cosmonaut-physician and members of three crews (MIR-15, -16, and -17) carried out a program of hematological investigations. Most of the changes related to the red blood system and included reduction in hemoglobin and hematocrit. Erythrocytes had decreased concentration and took on abnormal forms. There were also signs of altered metabolism of erythrocytes. Of interest are phase-by-phase variations in the levels of erythrocytes in the course of long-term stay in microgravity, and absence of a convincing correlation between hemoglobin, erythrocyte and hematocrit levels. But for lymphocytosis that returned to the norm already on the first day of recovery, no material changes occurred to the leukocyte profile. Investigations at the landing site displayed erythropenia, decreased reticulocytes and ensuing reticulocyte reaction, and gradual regain of the erythrocyte number that can be viewed as a normal physiological reaction of the blood system to the set of factors of spaceflight and early readaptation. Besides, the investigations showed a large individually of blood reactions to prolonged stay in space flight.  相似文献   
945.
946.
The effect of neutron irradiation and post-irradiation thermal annealing on tensile and impact properties of Cr–Ni–Mo steel used for WWER-1000 reactor pressure vessel (RPV) manufacturing was studied. A gap in yield stress and ultimate tensile stress fluence dependence at the fluence range of 0–3×1023 neutrons m−2 was observed while ductile-to-brittle transition temperature (DBTT) was continuously increasing with damage dose. The post-irradiation annealing recovery of tensile properties was found to be higher than the one of impact properties. Over-recovery of tensile properties due to 460 and 490°C post-irradiation annealings were observed. The annealing effectiveness of WWER-440 and WWER-1000 grades was compared. Nickel was supposed to affect both the radiation sensitivity and the post-irradiation residual DBTT shift of WWER-1000 type steel.  相似文献   
947.
Current collective and individual dose rates to humans are estimated from the consumption of seafood harvested in the Arctic Seas. Statistical data on catches are used for the dose assessment, as well as observed data (1991-1994) on the radioactivity of marine biota. The actual collective dose rates to the world population are estimated to be: 2.7-4.5 manSv/year due to consumption of seafood from the Barents Sea, and 0.03 manSv/year-due to seafood from the Kara Sea. The contribution of 137Cs to the collective dose rate is about 90%. Current individual dose rates to high-rate consumers are estimated to be: 2.6 x 10(-6) Sv/year due to seafood from the Barents Sea; and 4.2 x 10(-6) Sv/year-due to seafood from the Kara Sea. The future radiological impact of the radioactive waste (RW) disposals in the Kara Sea is simulated for the period over 1000 years, using the regional box model of the Arctic Seas. The model predictions are made for three hypothetical scenarios of long-term radionuclide releases, prepared within the framework of the International Arctic Seas Assessment Project. The potential collective dose to world population truncated to 3000 AD is shown to be not higher than 0.13 manSv. The maximum individual dose rates from Arctic seafood consumption are estimated to be about 1.2 x 10(-7) Sv/year. The predicted doses are much smaller than the actual doses due to the current radioactive contamination of the Arctic Seas.  相似文献   
948.
The intestinal absorption of vitamin B12 and its blood content have been proved to lower in patients with chronic enterocolitis. Dietetics including kumiss and shubat promotes normalization of vitamin B12 absorption (p less than 0.05), its blood content growth (p less than 0.05), the intestinal microflora becoming normal.  相似文献   
949.
950.
The algorithms of numerical solution of the system of quasihydrodynamic equations, simulating a dense electron-hole plasma in binary heterostructures, are considered and treated.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 51, No. 3, pp, 492–501, September, 1986.  相似文献   
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