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排序方式: 共有3603条查询结果,搜索用时 15 毫秒
991.
992.
DA Southgate WJ Branch MJ Hill BS Drasar RL Walters PS Davies IM Baird 《Canadian Metallurgical Quarterly》1976,25(10):1129-1135
During a metabolic ward study, the addition of dietary fiber in the form of wheat bran biscuits to the diet of five volunteer subjects resulted in an increase in the stool wet weight and fecal solids. The excretion of fecal solids was highly correlated with the intake of unavailable carbohydrates, and fecal losses of water were similarly correlated with fecal excretion of these constituents. The major component of the increase in fecal solids was due to the noncellulosic polysaccharide fraction of dietary fiber. There was an increased fecal excretion of nitrogen fat and energy by most subjects when the supplement was eaten. However, the increased loss of energy in the feces was only 40-80 kcal/day, and therefore a large supplemental intake of dietary fiber had only minor effects on energy metabolism. Supplemental fiber is thus unlikely to induce a useful loss of calories in the management of obesity. The addition of dietary fiber caused an increased excretion of most inorganic constituents, particularly sodium and phosphorus; increased excretion of iron and magnesium was also found in two subjects. 相似文献
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996.
RL Woosley DG McDevitt AS Nies RF Smith GR Wilkinson JA Oates 《Canadian Metallurgical Quarterly》1977,56(6):980-984
In a previous clinical study we demonstrated that tocainide is effective in the suppression of ventricular ectopic depolarizations (VEDs) after single oral doses. This information provided the basis for evaluating this drug's antiarrhythmic efficacy after multiple dose administration according to a loading-maintenance regimen. Twelve patients with stable VEDs were given loading doses of tocainide (400-600 mg) with maintenance doses every 12 hours. Every 48 hours the dose was increased until either arrhythmia suppression to less than 25% of VED frequency during placebo administration or side effects occurred. Computer analysis of 12-hr telemetric ECGs taken 24-36 hr after each dosage increment documented effective suppression (76-95%) in 8 of 12 patients. Those subjects demonstrating suppression were randomly assigned to a cross-over study of placebo or active drug at the dosage found effective in the dose-ranging phase. Dosages for the cross-over stage ranged from 400 to 1100 mg every 12 hours. Comparison of the two five-day periods documented suppression in these patients (mean +/- SE = 83.3 +/- 4%). No serious side effects or undue drug accumulation occurred during the study. The data indicate that tocainide can effectively suppress VEDs for 8-12 hours in many patients and that continuous suppression could be possible on an 8-12 hr dosage regimen. 相似文献
997.
Experiments were conducted to determine the effects of pargyline, a monoamine oxidase inhibitor, onmale rat reproductive organ weights, testicular histology, and plasma testosterone levels. Pargyline was administered to various groups of rats by implanting it, either dissolved or in a powder form, in Silastic tubing capsules. Additional rats were injected with pargyline solutions. The effects of pargyline.appeared to be age-related with younger animals, weighing under 400 gm (less than 100 days of age), showing a decrease in testicular and accessory organ weights and plasma testosterone. Older animals did not show a decrease in organ weights. Testicular histology in the pargyline-treated groups showed sloughage of cellular material into the tubular lumina, decreases in the number of cell layers, and a reduction of the number of mature spermatocytes. Other areas in the same testis were normal, however, and resembled control histology. The results suggest that pargyline can have detrimental effects on testicular function and that the effects may be age-related. 相似文献
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Finger ridge-counts of an American White, American Black and an African Black sample were subjected to factor analysis. The analysis was carried out using correlation matrices computed from 10-ridge counts, each finger being represented by its largest count, and from 20 ridge-counts, using both radial and ulnar counts for each finger. The 20 count analysis was much more informative, demonstrating the relative independence of the radial and ulnar sides of the fingers. Moreover, the radial and ulnar counts themselves generally resulted in two factors reflecting counts on the ulnar digits and the median digits. The independence of the thumb was also demonstrated. There was considerable intersample consistency, although some evidence of sex and race variation was observed. 相似文献