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21.
This report summarizes the proceedings of a conference on quantitative methods for assessing the risks of developmental toxicants. The conference was planned by a subcommittee of the National Research Council's Committee on Risk Assessment Methodology 4 in conjunction with staff from several federal agencies, including the U.S. Environmental Protection Agency, U.S. Food and Drug Administration, U.S. Consumer Products Safety Commission, and Health and Welfare Canada. Issues discussed at the workshop included computerized techniques for hazard identification, use of human and animal data for defining risks in a clinical setting, relationships between end points in developmental toxicity testing, reference dose calculations for developmental toxicology, analysis of quantitative dose-response data, mechanisms of developmental toxicity, physiologically based pharmacokinetic models, and structure-activity relationships. Although a formal consensus was not sought, many participants favored the evolution of quantitative techniques for developmental toxicology risk assessment, including the replacement of lowest observed adverse effect levels (LOAELs) and no observed adverse effect levels (NOAELs) with the benchmark dose methodology.  相似文献   
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Summary.  The association of poor education and poor health has been consistently observed in many studies and in various countries. Thus far, studies examining the mechanisms underlying this association have looked at only a limited set of potential pathways. This study simultaneously examines six distinctive pathways, which have been hypothesized to link education and health and found support from previous studies. A causal analysis of education and health was performed using structural equation models. Data were used from six phases of the National Child Development Study, which is based on following up an initial sample of 17416 children who were born in 1958. The association between education and health appears to be explained by a combination of mechanisms: adolescent health and adult health behaviours for men and women, adult social class among men and parental social class among women. We conclude that improvements in population educational attainment may not automatically lead to improvements in population health, and that health policies for improving health and reducing health inequalities need to target specific causal pathways.  相似文献   
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Compliments are often viewed primarily as a linear event in which one person expresses approval or admiration of another. Far less attention has been given to the circular nature of compliments and the manner in which they enhance the positions of both the giver and the receiver of the compliment. Therapeutic compliments have proven to be highly effective means of motivating clients, while at the same time increasing therapeutic leverage. This article proposes that compliments should be purposefully given, and that the type of compliment should vary with the stage of therapy and the intended response of the client to the compliment.  相似文献   
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The arguments for and against policy measures designed to increase birth rates in European countries are reviewed. The author concludes that the deterioration of the environment associated with the growth of population in developed countries outweighs any arguments in favor of policy measures to increase fertility.  相似文献   
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"The purpose of this paper is to look at what has been achieved by the transmigration program [in Indonesia], to examine the major problems that have arisen and to consider the present constraints which now cast some doubt upon the future of the program." A historical overview of government policies from 1905 to 1988 is provided, and problems of land supply, land use, and lack of funds are discussed. Data are from the 1961 and 1980 Indonesian censuses. (SUMMARY IN FRE AND SPA)  相似文献   
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Information about board-and-care homes reported in the media and in federal committee hearings indicates that they are shoddy and exploitative environments that do not provide adequate care. Research done in board-and-care homes in recent years, however, demonstrates that they can provide adequate care and a satisfying environment for some of the people they serve. Policy at the federal, state, and local levels should be guided by both the need to assure the health and safety of board-and-care residents and the needs of residents and operators identified in scientific studies.  相似文献   
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How our current system works and what changes need to be made are the subjects of intense scrutiny by policy makers today. One of the primary areas of concern with our present health care system is its accessibility to the average American, in terms of both price and ability to obtain insurance. With an estimated 37 million Americans without health care insurance, and countless others severely underinsured, this issue will lie at the core of any health care reform that results from the current debate. One possible approach to the uninsured problem that might alleviate the situation is community rating.  相似文献   
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