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911.
JR Sutton AC Bryan GW Gray ES Horton AS Rebuck W Woodley ID Rennie CS Houston 《Canadian Metallurgical Quarterly》1976,47(10):1032-1037
The severity of acute mountain sickness (AMS) was investigated in healthy volunteers, airlifted to high altitude (5,360 m). Blood gases were measured at 2,990 m and 5,360 m. Symptoms of AMS were found in all subjects, but ranged from malaise to vomiting with intractable headache. The clinical severity of AMS was directly related to the arterial PCO2 and inversely to pH, but unrelated to the PO2 on arrival at high altitude. However, PO2 fell and was lowest 48 h after arrival at high altitude in those subjects with the most severe AMS. These were the only subjects to show an increase in the alveolar-arterial PO2 difference and in the venous admixture ratio during the first 48 h. These abnormalities in gas exchange, which developed in the subjects with the most marked cerebral symptoms, suggest that the manifestations of cerebral and pulmonary dysfunction at altitude develop simultaneously, a finding that suggests coexisting cerebral and pulmonary edema. 相似文献
912.
The study involved three levels of dietary zinc (deficient, marginal, and adequate) and four hormonal conditions; namely, no steriods, norethindrone, mestranol, and norethindrone plus mestranol. The steroids were incorporated into diets and fed to 11-wk-old female Sprague-Dawley rats. After 10 wk of treatment, various tissues were excised for mineral assays by atomic-absorption spectrophotometry. Both steroids, reduced weight gain. Mestranol depressed plasma zinc, tibia copper and magnesium, and liver iron, but elevated the zinc levels in liver and erythrocytes, plasma copper, liver magnesium and calcium, and iron content of tibia and heart. In general, the effect was most prominent with adequate zinc but diminished in magnitude with the reduction of zinc intake. In addition, norethindrone increased heart iron and tibia calcium. Mestranol appeared to be the main causative factor and may have induced a possible shift of minerals from one pool to another. As expected, zinc deficiency resulted in the reduction of zinc concentrations of plasma, tibia, kidney, and pancreas, and the elevation of copper, iron, magnesium, and calcium concentrations of various tissues. 相似文献
913.
DG Hutson R Zeppa JU Levi ER Schiff AS Livingstone P Fink 《Canadian Metallurgical Quarterly》1977,185(5):605-612
Twenty-four patients with leukopenia and/or thrombocytopenia improved these deficiencies after distal splenorenal shunts. The average white blood cell count for 23 neutropenic patients increased by an average 1000 cells/cu.mm p less than .01. The average platelet count for 13 thrombocytopenic patients increased by more than 40,000, p less than .02. Analysis of the data showed that patients older than 50 years, with a history of alcoholic liver disease and sinusoidal hypertension greater than 15mm Hg were most likely to correct leukocyte and platelet defects after distal splenorenal shunts. 相似文献
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A method of measuring a time-dependent heat flux is described and results of a verification are presented.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 33, No. 1, pp. 111–115, July, 1977. 相似文献
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