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61.
62.
A P Harris 《Anesthesia and analgesia》1992,75(1):150-152
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Epithelial ovarian neoplasms of low malignant potential, also called borderline ovarian tumors, have various features of malignancy, but they do not invade the ovarian stroma. Women with these tumors usually are younger when diagnosed and have better prognoses than do women with invasive tumors. There have been few epidemiologic studies of borderline tumors, and it is unclear whether there are etiologic differences between the two types of tumor behavior. Combined data from nine case-control studies, conducted from 1974 to 1986 and representing 327 white women with tumors of low malignant potential and 4,144 white controls, were used to evaluate the relation between these tumors and personal characteristics related to invasive ovarian cancer. The risk profile for tumors of low malignant potential was found to be similar to that for invasive tumors, with two exceptions: Compared with that of invasive tumors, risk of borderline tumors was less clearly reduced among women who had used oral contraceptives and more clearly elevated among women with a history of infertility. 相似文献
65.
B. Vaidya P. E. Harris P. Barrett P. Kendall-Taylor 《Postgraduate medical journal》1997,73(866):817-819
We report a case of Riedel''s thyroiditis presenting with a systemic illness, life-threatening stridor and a stony hard goitre. Diagnosis was confirmed by open thyroid biopsy. Treatment with corticosteroid resulted in a dramatic improvement. A possible autoimmune mechanism in the pathogenesis of Riedel''s thyroiditis is discussed. 相似文献
66.
Sex-specific effects for body mass index (BMI) were explored in a newly established, population-based Norwegian twin panel. The sample includes 5,864 individuals, aged 18–25 years, who responded to a questionnaire containing items for zygosity classification, height, weight, health, health-related behaviors, well-being, and demographic information. Among the 2,570 intact pairs who returned the questionnaire there were 416 identical (MZ) male pairs, 387 fraternal (DZ) male pairs, 528 MZ female pairs, 443 DZ female pairs, and 796 unlike-sexed pairs. Alternate sets of models testing for either sex-specific genetic or environmental parameters were evaluated using structural equation analysis. Results from the most parsimonious model indicated that the genes contributing to variation in BMI are not identical for men and women; rather, some genetic effects were shared by the sexes and some were unique to each sex. Total variation in BMI could be explained by sex-specific additive genetic effects, as well as genetic and non-shared environmental effects common to men and women. Estimates of heritability were .708 for men and .789 for women, and the male-female genetic correlation was 0.622. The series of models specifying sex-specific shared environment also fit the data and suggests that shared environmental factors may be important for males but not for females. The findings raise questions concerning the relationship between sex-specific effects for BMI and sex differences in health outcomes. ©1995 Wiley-Liss, Inc. 相似文献
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The purpose of this paper is to evaluate the efficacy and clinical information obtained from the authors' first 17 consecutive descending venograms. All 17 patients had chronic venous disease refractory to standard conservative and surgical measures. The standard classification of valvular insufficiency was used in evaluating these venograms. There were no deaths, slight morbidity and minimal patient discomfort. In 16 patients meaningful clinical information was derived from the venograms, with 7 patients having deep venous valvular surgery. Descending venography will demonstrate the site of incompetent valves and estimate the degree of reflux. This test is necessary before anticipated reconstruction of deep vein valves. 相似文献
69.
The objective of this study was to determine the effect of reducing dietary fat content from 40 to 30% of total energy on body composition and insulin sensitivity in rats. Female Sprague-Dawley rats were fed either a control diet (30% energy as fat) or a high fat diet (40% energy as fat) for 10 wk. In vivo glucose tolerance tests indicated that both basal and glucose-stimulated insulin concentrations were elevated in rats fed the high fat diet. Two groups of rats offered the high fat diet were then fed the control diet (HF,C) and two that had received the high fat diet were then fed a diet (30% energy as fat) containing a fat-mimetic carbohydrate (HF,M). Two groups continued to receive the high fat diet and two groups continued to receive the control diet. Rats were killed 1 and 2 wk after the diet switch. In vivo glucose tolerance tests indicated that insulin sensitivity was corrected in HF,C and HF,M rats after 3 d. Body fat content was greater in rats fed the high fat diet and remained high after 7 d of consuming either diet with 30% of energy from fat. There was no effect of diet on liver fatty acid utilization or on diaphragm glucose oxidation. Adipocytes from all treatment groups were insulin resistant, possibly due to feeding status or age of the rats. The results of this study suggest that a moderate reduction in fat intake, from 40 to 30% of energy, can produce a rapid improvement of insulin sensitivity in insulin-insensitive rats, independent of changes in body fat content and irrespective of the means used to reduce dietary fat content. 相似文献
70.
Mechanisms of multidrug resistance in cancer treatment. 总被引:7,自引:0,他引:7