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51.
The results of a combined roentgenoradionuclide investigation of the lungs were studied in 45 persons at risk of developing chronic nonspecific pulmonary diseases, diagnosed in a mass screening of 3000 workers at an industrial enterprise. The results of fluorographic, roentgenoscopic and roentgenographic investigations of the lungs, roentgenopneumopolygraphy and radionuclide investigation of lung perfusion (pulmoscintigraphy with 99mTc-labeled albumin macroaggregates) were compared. During this combined investigation the signs of nonspecific pulmonary diseases were diagnosed in 40% of the patients, changes of the pulmonary blood flow--in 71%, changes of ventilation--in all the examinees. A conclusion was made of the necessity of additional combined investigation of patients belonging to risk groups, identified during mass screenings.  相似文献   
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Plasma Physics Reports - The results of studies of optical properties of plasmas in the framework of the self-consistent method of moments, which are in satisfactory agreement with experimental...  相似文献   
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In acute experiments on cats, the diameter changes of the arterio-venous anastomoses in a number of vascular zones and their shunting coefficient were studied under the pressor reflexes; the method of injections of the microspheres was used. In these experiments the shunting capacity of the arterio-venous anastomoses was shown to be decreased in the small intestine, the spleen, the kidney and the gastrocnemius muscle under the pressor synocarotid reflex and the electrical stimulation of the somatic afferents.  相似文献   
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The inhibition of neurotoxic esterase activity in chicken brain has been studied in vitro and in vivo. Aphos exposure, causing chicken paralysis, has demonstrated that the initial stage of delayed neurotoxicity was significant esterase activity inhibition (by 60-80%) within 3-24 hours after the pesticide administration. The inhibition of cholinesterase activity occurred both in the blood and sciatic nerve. The delayed conduction through peripheral nerves caused by demyelination has been revealed in the latent period (before the clinical signs of intoxication).  相似文献   
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Applied Biochemistry and Microbiology - This review concerns the mechanisms of bacterial cell survival based on the induction of hibernation factors (HFs) that suppress protein synthesis via the...  相似文献   
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We investigated the role of the ATP-sensitive potassium channel opener pinacidil and blocker glibenclamide on guinea pig liver mitochondrial function, and a possible significance of pinacidil in the pharmacological treatment during myocardium dystrophy. First, a series of experiments was performed to determine the effect of pinacidil and glibenclamide on mitochondrial oxygen consumption. We found that pinacidil increased the rate of mitochondrial respiration for FAD-generated substrate (succinate oxidation), but was most effective for α-ketoglutarate oxidation with enhancement of respiratory control ratio. Oxidation of FAD-generated substrate inhibited efficiency of phosphorylation for α-ketoglutarate oxidation in pinacidil-treated animals. Glibenclamide decreased the rate of respiration with the lowest value of efficiency of phosphorylation, especially for α-ketoglutarate oxidation. A second series of experiments was performed to determine the effects of pinacidil and glibenclamide on oxidative phosphorylation during adrenaline-induced myocardium dystrophy. The increase in respiratory control ratio and efficiency of phosphorylation for α-ketoglutarate oxidation was greater than for succinate oxidation in mitochondria of pinacidil-pretreated animals during myocardium dystrophy. Inhibitory analysis with malonate suggested that endogenous succinate increased oxidation of NADH-generated substrates in mitochondria. Pinacidil is mainly involved in the adrenaline-induced alterations of mitochondrial function due to elevation of phosphorylation efficiency for α-ketoglutarate oxidation and a decreased level of lipid peroxidation.  相似文献   
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In a cross-sectional study, the serum concentrations of inhibin B and prolactin of 96 male current welders were compared with the concentrations measured in 96 age-matched referents. Also, 23 patients who were all former welders diagnosed as having welding-related manganism were studied. The current welders' geometric mean (GM) airborne exposure to manganese (Mn) was 121 µg m-3 (range 7-2320). The serum concentrations of prolactin adjusted for age and smoking habits (GM 193 mIU l-1 vs. 166 mIU l-1; p=0.047) and inhibin B adjusted for alcohol consumption (arithmetic mean (AM) 151 ng l-1 vs. 123 ng l-1; p=0.001) were higher in the welders compared with the referents. The whole blood Mn concentration was associated with the serum prolactin concentrations. Tobacco smoking resulted in lower serum prolactin concentrations. The GM serum prolactin concentrations of the patients did not significantly differ from that of the referents, but their AM serum inhibin B concentration was statistically significantly lower. The results may suggest an effect of Mn on the pituitary that is reversible upon cessation of exposure. Lower inhibin B concentrations in the patients could point to a functional impairment of the testicular Sertoli cells, that may be caused by a welding fume component or other factors in their work environment.  相似文献   
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