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11.
This study examined the effect of Testofen, a specialised Trigonella foenum-graecum seed extract on the symptoms of possible androgen deficiency, sexual function and serum androgen concentrations in healthy aging males. This was a double-blind, randomised, placebo-controlled trial involving 120 healthy men aged between 43 and 70 years of age. The active treatment was standardised Trigonella foenum-graecum seed extract at a dose of 600?mg/day for 12 weeks. The primary outcome measure was the change in the Aging Male Symptom questionnaire (AMS), a measure of possible androgen deficiency symptoms; secondary outcome measures were sexual function and serum testosterone. There was a significant decrease in AMS score over time and between the active and placebo groups. Sexual function improved, including number of morning erections and frequency of sexual activity. Both total serum testosterone and free testosterone increased compared to placebo after 12 weeks of active treatment. Trigonella foenum-graecum seed extract is a safe and effective treatment for reducing symptoms of possible androgen deficiency, improves sexual function and increases serum testosterone in healthy middle-aged and older men.  相似文献   
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This paper presents three small sample tests for testing the heteroscedasticity among regression disturbances. The power of these tests are compared with two of the leading tests for this hypothesis, one by Goldfeld and Quandt [5] and the other by Theil [17]. We also provide a heuristic method of selecting the number of middle observations to be deleted for the Goldfeld-Quandt type of tests.  相似文献   
14.
饶伟新 《民族研究》2005,(6):92-100
针对目前客家学界认为今日"客家"的名称产生于明清时期,等同于明清文献中的"客佃"、"客籍"这一流行观点,本文以清代以来赣南文献中的"客佃"、"客籍"与"客家"为例,从区域社会史的角度对这些术语的具体历史语境和历史内涵进行考察和分析.指出清代的"客佃"、"客籍"作为清代移垦过程和户籍制度背景下特定的历史产物,其实是一个与"土著"、"土籍"相对的移民范畴,而今日所谓的"客家",则是在晚清民国以来社会文化变迁和学术发展背景下出现或建构的一个具有人类学意义的民系范畴,二者完全属于不同的历史范畴,故而不能相提并论.  相似文献   
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Nonparametric test statistics are constructed by considering the medians in subsamples of appropriate size taken -from n independent observations. These tests are shown to be sensitive to both heavy and moderate tailed distributions.  相似文献   
17.
In this paper we consider the problem of obtaining best linear unbiased estimators of individual response coefficients in a Random Coefficient Linear Regression (RCR} Model, comparing alternative estimators for these response vectors through a simulation study. We also provide an empirical example that illustrates the estimation procedure proposed here.  相似文献   
18.
A simple adaptation of a distribution-free method due to Scholz (1978) and Sievers (1978) for inference in a single regression setting is proposed for inference about the difference in slopes of two regression lines. We assume that the data are obtained from a designed experiment with common regression constants. A comparison of the proposed method to its competitors-one due to Hollander and the other due to Rao and Gore-indicates superiority of the new method.  相似文献   
19.
In this article, we present the effects of three hypothesized protective factors—social activities, school-related activities, and anti–substance use media messages—on adolescent tobacco and alcohol use. Data were drawn from the “Monitoring the Future” research project, which was conducted by the Institute for Social Research at the University of Michigan. The sample included 2,551 twelfth-grade students. The results of the structural equation model showed that exposure to media anti-drug messages had an indirect negative effect on tobacco and alcohol use through school-related activity and social activity. The results suggest that comprehensive ecological interventions encompassing media, family, and school can increase the preventive effects of adolescent's substance use.  相似文献   
20.
The MINQUE and its modifications are considered for estimating the variances of the balanced one-way random effects model. The effects of the a priori values on the estimators of the variances are examined in detail. The Mean Square Errors of the estimators are compared for variations in the prior values of the unknown variances.  相似文献   
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