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971.
The indications for hormone replacement therapy (HRT) in postmenopausal women is the treatment of climacteric symptoms and the prevention of osteoporosis. Women with systemic lupus erythematosus (SLE) are more likely to have a premature menopause, osteoporosis and cardiovascular disease. HRT can induce SLE flares and cardiovascular or venous thromboembolic events. Therefore it should not be used in women with active disease or those with antiphospholipid (aPL) antibodies. In general, it should be used only for patients without active disease, a history of thrombosis or aPL antibodies. Non-oral administration of estrogen is recommended because of its lesser effect on coagulation. With regard to the progestogen, progesterone or pregnane derivatives are preferred. Otherwise, non-estrogen-based strategies should be used. 相似文献
972.
WALTER J. WESSELS 《Journal of Labor Research》2007,28(1):135-146
Card and Krueger's (1995) difference-in-difference study of the 1990-1991 federal minimum wage hikes compared states by the proportion of workers directly affected by the minimum wage. They found "no evidence that the increase in the minimum wage significantly lowered teenage employment rates more in highly affected states" and they concluded the minimum wage did not reduce employment. Their paper was highly influential and convinced many that the minimum wage did not reduce employment. However, when I apply their model to the 1996-1997 federal minimum wage hike, I find that increases in the minimum wage significantly lowered teenage employment rates more in highly affected states. Using Card and Krueger's interpretation, this implies the minimum wage did reduce teenage employment. 相似文献
973.
The Experience-Earnings Profile: Productivity-Augmenting or Purely Contractual? Evidence from the UK
William J. Moore Robert J. Newman Geoffrey K. Turnbull 《Journal of Labor Research》2007,28(3):417-435
We test the human capital interpretation of the experience-earnings profile. Does the upward sloping portion of the experience-earnings
profile reflect on-the-job training which in turn causes the experience-productivity profile to slope upwards, or do purely
contractual factors determine the nature of life-cycle earnings. Herein, we provide additional evidence on the relationship
between productivity and earnings by examining earnings differentials in the UK academic labor market for economists. Using
a test first suggested by Mincer, we find that the empirical results are consistent with human capital theory. We find that,
although the positive relationship between earnings and experience persists when individual productivity measures are included
in the salary equations for lecturers and senior lecturers, the positive relationship becomes statistically insignificant
when the same productivity measures are included in the salary equations for professors. For lecturers and senior lecturers,
the experience-salary profile properly reflects the structure of the national pay scale rather than variations in individual
research productivity. At the professor level, where individual salaries are not determined by a pay scale, the data support
the human capital explanation of the positive experience-earnings profile.
相似文献
Robert J. NewmanEmail: |
974.
Proponents of the common factors movement in marriage and family therapy (MFT) suggest that, rather than specific models of therapy, elements common across models of therapy and common to the process of therapy itself are responsible for therapeutic change. This article-the second of two companion articles-reports on a study designed to further investigate common factors in couple therapy. We used grounded theory techniques to analyze data from interviews with MFT model developers Dr. Susan M. Johnson, Dr. Frank M. Dattilio, Dr. Richard C. Schwartz, former students of Dr. Johnson and Dr. Schwartz, and each of their clients who had been successful in couple therapy. This article reports model-independent variables, that is, general aspects of therapy that are not directly related to the therapist's model. Model-independent categories include client variables, therapist variables, the therapeutic alliance, therapeutic process, and expectancy and motivational factors, each with several subcategories. We also present a conceptual framework that outlines how model-dependent and model-independent common factors may interact to produce change. We discuss our findings and proposed framework in relation to the current common factors literature in psychology and MFT. We also discuss clinical, training, and research implications. 相似文献
975.
Communities across the nation have become increasingly concerned about inhalant use and use of harmful legal products among youth because of increasing prevalence rates and deleterious health consequences from abusing these products. The increasing concern of communities about inhaling and ingesting legal products has been coupled with increasing awareness and concern about ability of youth to access and abuse a variety of other legal retail products. There are few examples of scientifically designed community prevention projects that seek to reduce youth abuse of such legal products. This article describes a community prevention trial that is designed to reduce sales of inhalants and other harmful legal products to youth and demonstrates how the retailer component of the trial can be rigorously evaluated. It also shows how data from youth purchase attempts can complement survey data from retailers. 相似文献
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In recent years, a variety of regression models, including zero-inflated and hurdle versions, have been proposed to explain the case of a dependent variable with respect to exogenous covariates. Apart from the classical Poisson, negative binomial and generalised Poisson distributions, many proposals have appeared in the statistical literature, perhaps in response to the new possibilities offered by advanced software that now enables researchers to implement numerous special functions in a relatively simple way. However, we believe that a significant research gap remains, since very little attention has been paid to the quasi-binomial distribution, which was first proposed over fifty years ago. We believe this distribution might constitute a valid alternative to existing regression models, in situations in which the variable has bounded support. Therefore, in this paper we present a zero-inflated regression model based on the quasi-binomial distribution, taking into account the moments and maximum likelihood estimators, and perform a score test to compare the zero-inflated quasi-binomial distribution with the zero-inflated binomial distribution, and the zero-inflated model with the homogeneous model (the model in which covariates are not considered). This analysis is illustrated with two data sets that are well known in the statistical literature and which contain a large number of zeros. 相似文献
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