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排序方式: 共有371条查询结果,搜索用时 15 毫秒
1.
Maternal weight gain, infant birth weight, and diet: causal sequences   总被引:4,自引:0,他引:4  
The causal sequence maternal nutrition----maternal weight gain----infant birth weight is not sustained by available evidence except under extreme nutritional deprivation. For maternal weight change, diet effects of near starvation are unequivocal. With chronic undernutrition or social deprivation, diet effects are inapparent or modest (conditional on pregnancy stage, diet supplement, and prepregnancy weight). For birth-weight change, diet effects of near starvation are likewise unequivocal and modest with chronic undernutrition or social deprivation. The complete causal sequence has been demonstrated only below a famine threshold. Outside famine, effects are modest (conditional on baseline nutrition, timing, and content of diets, possibly also on infant sex and energy expenditure). High-protein concentrations have produced adverse effects. Micronutrients and consequent fluid retention could have favorable effects. Diet effects on birth weight apparently bypass maternal weight change. Hence, to enhance birth weight, maternal diet appears to deserve more attention than does weight gain.  相似文献   
2.
This paper concerns the diagnostic classification of nonaffective acute remitting psychosis (NARP), which we also term acute brief psychosis. We argue that NARP can be delineated from both schizophrenia and the affective psychoses and considered as a single diagnosis. As indicated by the term NARP, four criteria would be central to the diagnosis: 1. nonaffective, 2. acute onset (over less than two weeks), 3. recovery within a brief duration (less than six months), and 4. psychosis broadly defined. We review the rationale and the empirical evidence for this proposed classification.  相似文献   
3.
Authors and authorship--reform or abolition?   总被引:5,自引:5,他引:0       下载免费PDF全文
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4.
The Critical Time Intervention Project is a three-year clinical trial which tests a time-limited, supportive intervention to reduce recurrent homelessness among mentally ill men moving from a shelter to the community. Along with a comparison of nights spent homeless and other outcomes, the evaluation of the Critical Time Intervention includes a comparison of the relative costs of the intervention, compared to usual treatment. Such cost effectiveness analyses are difficult to perform and are rarely applied to mental health treatments. This paper presents the general scheme of this analysis and discusses critical issues in the construction and measurement of cost variables. Preliminary results which have implications for the cost analysis are presented.  相似文献   
5.
The problems of separating highly confounded hereditary and environmental factors are reviewed from an epidemiological point of view. Once the fact rather than the appearance of familial aggregation is established, one can search for and analyze strong indicators of either genetic or environmental effects, and ultimately attempt their separation by strong design. Indicators of genetic effects are classified according to the presence or absence of family recurrence. In the presence of family recurrence, three analytic approaches are available: segregation analysis, linkage, and heritability estimates. In the absence of family recurrence, biological markers and endogamous groups can be used. Indicators of environmental effects are also classified according to the presence or absence of family recurrence of a disorder. In the presence of family recurrence, three environmental indicators are considered: non-Mendelian clustering, such as time of onset versus age in family clusters, and sex clusters; cohabitational effects; and maternal transmission. In the absence of family recurrence, environmental indicators include secular trends, migration, time and place clusters, family size, and birth order. Designs that aim to separate heredity and environment include twin studies, fixed clusters that include a variety of degrees of relatedness (particularly the family set-design), and comparisons of separately reared relatives. The strengths and weaknesses of twin studies and family set designs are reviewed. Separately reared relatives provide the most cogent tests of genetic and environmental hypotheses. Among these, separated twin pairs, half-sibs, and relatives separated through institutional placement or adoption are considered. Adoption strategies are illustrated by the Danish adoption studies of schizophrenia, criminality, and alcoholism, and these studies are reanalyzed from the perspective of epidemiological case-control and cohort studies. Finally, the potential uses of multiple family settings as they occur in the general population are briefly discussed.  相似文献   
6.
7.
Pioneering community-oriented primary care.   总被引:5,自引:0,他引:5  
This is a retrospective report on the importance of Kark and Cassel's 1952 paper on community-oriented primary care (COPC). In 1978, WHO and UNICEF endorsed COPC. However, the ideas girding and framing this approach had first been given full expression in practice some four decades earlier. In Depression-Era South Africa, Sidney Kark, a leader of the National Department of Health, converted the emergent discipline of social medicine into a unique form of comprehensive practice and established the Pholela Health Center, which was the explicit model for COPC. COPC as founded and practiced by Kark was a community, family and personal practice; it also was a multidisciplinary and team practice. Furthermore, the innovations of COPC entailed monitoring, evaluation, and research. Evaluation is the essence of Kark and Kassel's paper, which offers a convincing demonstration of the effects of COPC. Its key findings include the following: 1) that there was a decline in the incidence of syphilis in the area served by the health center; 2) that diet and nutrition improved; and 3) that the crude mortality rate as well as the infant mortality rate--the standard marker--declined in Pholela. In the succeeding decades, OPC had an international legacy (through WHO and H. Jack Geiger's influence in the US Office of Economic Opportunity), which came full circle in the 1980s, when a young generation of South Africans began to search their history for models for their health care programs at the dawn of the post-Apartheid Era.  相似文献   
8.
The reliability of self-reports of sexual behaviors related to HIV transmission was examined in a study of homeless men with severe mental illness. Thirty-nine patients of a New York City shelter psychiatric program were interviewed about their sexual behaviors in the past six months. The same interview was administered twice, with a one- to two-week interval between interviews. Test-retest reliability was assessed using kappa and intraclass correlation coefficients. Reliability estimates ranged from.49 to.93 for overall sexual activity, number of partners, and specific behaviors other than receptive anal sex. Reliability was lower for condom use. The authors conclude that reliable self-reports about sexual behavior can be obtained from homeless men with severe mental illness.  相似文献   
9.
Women in the time of AIDS: barriers, bargains, and benefits.   总被引:2,自引:0,他引:2  
We comment here on the implications of new HIV prevention technologies (physical and chemical barriers) for women's health and women's rights. Four relevant themes are selected that have emerged in the social and behavioral science literature: structural factors (global and national) limiting the availability of female condoms, control and empowerment with female-initiated HIV prevention technologies, covert use of female-initiated HIV prevention technologies, and male partners as part of the bargain for barriers. There is now a rich and diverse literature on all of these issues, relevant and informative (much is addressed in this issue), which we draw together in this commentary. Discussion of these themes suggests guidelines for policy, research, and action. First, the misconceptions, biases, and prejudices of global and national leaders, including donors, necessitate that we persevere in presenting data to them and engaging them in discussion. Second, we need to support women within their local social contexts to negotiate for their rights, balancing pragmatic approaches to their partners in their initiation of protection, and applying according to each situation as appropriate, a continuum from discretion and clandestine use to deception. Third, men have to be brought in as active participants, and their positive and negative experiences and interests inserted into practices and policies.  相似文献   
10.
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