首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   20603篇
  免费   366篇
  国内免费   2篇
管理学   3096篇
民族学   77篇
人才学   1篇
人口学   1959篇
丛书文集   85篇
教育普及   2篇
理论方法论   1797篇
现状及发展   1篇
综合类   323篇
社会学   9782篇
统计学   3848篇
  2023年   104篇
  2021年   124篇
  2020年   306篇
  2019年   416篇
  2018年   507篇
  2017年   689篇
  2016年   560篇
  2015年   382篇
  2014年   514篇
  2013年   3154篇
  2012年   716篇
  2011年   659篇
  2010年   495篇
  2009年   414篇
  2008年   487篇
  2007年   516篇
  2006年   509篇
  2005年   487篇
  2004年   447篇
  2003年   404篇
  2002年   455篇
  2001年   544篇
  2000年   559篇
  1999年   468篇
  1998年   343篇
  1997年   314篇
  1996年   328篇
  1995年   307篇
  1994年   290篇
  1993年   289篇
  1992年   345篇
  1991年   322篇
  1990年   288篇
  1989年   295篇
  1988年   288篇
  1987年   253篇
  1986年   246篇
  1985年   280篇
  1984年   268篇
  1983年   253篇
  1982年   220篇
  1981年   184篇
  1980年   168篇
  1979年   197篇
  1978年   179篇
  1977年   161篇
  1976年   138篇
  1975年   159篇
  1974年   121篇
  1973年   119篇
排序方式: 共有10000条查询结果,搜索用时 124 毫秒
51.
Determining the size and demographiccharacteristics of substance abuse populationsis extremely important for implementing publicpolicies aimed at the control of substanceabuse. Such information not only assists in theallocation of limited treatment resources bythe state, but also in the monitoring ofsubstance abuse trends over time and in theevaluation of innovative policy initiatives. Inthis study, we develop three composite measuresof treatment need. We then use these measuresto estimate treatment need for alcohol abuseand for controlled substance abuse within eachof Florida's 67 counties. This study providesan important empirical component of communityplanning, quantifying and, to a limited degree,specifying the level of need for the substanceabuse treatment of community residents. Anadditional benefit is the development of a costeffective and unobtrusive methodology fordetermining empirically when levels of need arechanging so that treatment levels can beadjusted accordingly. With proper use,policymakers can readily employ the methodologydeveloped in this study in Florida andelsewhere to make better-informed decisions inthe allocation of finite substance abusetreatment resources.  相似文献   
52.
A comprehensive set of variables that have been supported as contributing to overall health and general well-being were analyzed to determine their simple structure using factor analysis and their relative contribution using Pearson correlation. The contributors to general well-being had been theoretically grouped into: emotions, beliefs, temperaments, behaviors, sittuations, experiences and health. The empirical factor structure was compared with the theoretical structure used to develop the variables. Stability was investigated by comparing results with those of another geographically separated group. All subjects were normally functioning working adults. The results demonstrated the feasibility and potential usefulness of using self-report questionnaires with multivariate procedures to measure components of the global general well-being concept.  相似文献   
53.
Despite high expectations, students of the 1960 and 1976 presidentialdebates were unable to find much evidence that these eventssignificantly affected voters' candidate preferences. As a result,scholars have turned increasingly to cognitive consistency theoriesto explain viewers' reactions (Or nonreactions) to debates.This article argues that one key mediating variable determiningwhether or not voters are influenced by debates is their levelof political knowledge. Looking at the largely ignored 1980Carter-Reagan debate, we find that voters with generally lowlevels of knowledge are particularly affected by the debate,and significant shifts in candidate preferences do occur amongthis group. The evidence suggests that the debate was an importantfactor in Ronald Reagan's bid to unseat his Democratic opponent.  相似文献   
54.
Asian and White middle school children were shown photographs of unknown Afro-Caribbean, Asian, and White individuals of approximately the same age as themselves, and asked which one wax most like them, which one they would prefer to be, which ones they would prefer to engage in various activities with, and finally, to allocate positive and negative traits to the three groups or to nobody. A similar majority of both Asian and While children selected an own-race photograph as being most like them, but only about a half selected the own-race photograph as the one they would most like to he. For sharing activities, children showed a strong own-tender preference, followed by an own-race preference. White children stated a greater preference for sharing activities with White children, then with Afro-Caribbean children, and least with Asian children. Asian children preferred Asian and White children the most, Afro-Caribbean the least. On a stereotypes test, similar trends were obtained; White children evaluated While children highest and Asian lowest; Asian children tended to evaluate Asian children highest but to a nonsignificant extent. The relative proportion of Asian/White children in school appeared to have little systematic influence on the results, thus arguing against the contact hypothesis of prejudice reduction in its simple form.  相似文献   
55.
Recent studies have shown that group differences in marital stability and satisfaction can be predicted based on premarital relationship quality. There is also a growing literature indicating that there are distinct types of relationships, both premaritally and developmentally over time. This study examined the relationship between the four premarital types (Vitalized, Harmonious, Traditional, and Conflicted) identified by Fowers and Olson (1992) and relationship outcome over a 3-year period with 393 couples. A substantial relationship was found, with conflicted couples being the most likely to separate or divorce. Vitalized couples had the highest levels of satisfaction, followed by Harmonious, Traditional, and Conflicted couples. Traditional couples were less likely to have divorced than Harmonious couples, even though Harmonious couples had higher premarital relationship satisfaction scores.  相似文献   
56.
This paper presents the results of a study that identified how often a probabilistic risk assessment (PRA)should be updated to accommodate the changes that take place at nuclear power plants. Based on a 7-year analysis of design and procedural changes at one plant, we consider 5 years to be the maximum interval for updating PRAs. This conclusion is preliminary because it is based on the review of changes that occurred at a single plant, and it addresses only PRAs that involve a Level 1 analysis (i.e., a PRA including calculation of core damage frequency only). Nevertheless, this conclusion indicates that maintaining a useful PRA requires periodic updating efforts. However, the need for this periodic update stems only partly from the number of changes that can be expected to take place at nuclear power plants–changes that individually have only a moderate to minor impact on the PRA, but whose combined impact is substantial and necessitates a PRA update. Additionally, a comparison of two generations of PRAs performed about 5 years apart indicates that PRAs must be periodically updated to reflect the evolution of PRA methods. The most desirable updating interval depends on these two technical considerations as well as the cost of updating the PRA. (Cost considerations, however, were beyond the scope of this study.)  相似文献   
57.
Resocialization is pulled out of its structuralist roots and recast into an interactionist framework. Building on a substantive theory of the resocialization experience of becoming an adoptive parent, three theoretical properties of interactionist resocialization are presented. These can be summarized as involving unlearning and relearning some aspects of a core identity; the interpretation and active reconstruction of that identity which has reciprocal effects on all actors involved; and finally, the effects of both situational and trans-situational norms that give shape to the resocialization experience. Suggestions are made for other substantive areas of research that could be used for comparative analysis in order to further refine a formal theory of interactionist resocialization.  相似文献   
58.
We consider estimation of the number of cells in a multinomial distribution. This is one version of the species problem: there are many applications, such as the estimation of the number of unobserved species of animals; estimation of vocabulary size, etc. We describe the results of a simulation comparison of three principal frequent-ist' procedures for estimating the number of cells (or species). The first procedure postulates a functional form for the cell probabilities; the second procedure approxi mates the distribution of the probabilities by a parametric probability density function; and the third procedure is based on an estimate of the sample coverage, i.e. the sum of the probabilities of the observed cells. Among the procedures studied, we find that the third (non-parametric) method is globally preferable; the second (functional parametric) method cannot be recommended; and that, when based on the inverse Gaussian density, the first method is competitive in some cases with the third method. We also discuss Sichel's recent generalized inverse Gaussian-based procedure which, with some refine ment, promises to perform at least as well as the non-parametric method in all cases.  相似文献   
59.
1. Special attention is particularly important in addressing the mental health needs of HIV-infected women. These needs may involve issues such as concerns about present or future pregnancy; child-rearing, often as single parents; poverty, illicit drug use or addiction; and the potential lack of support services. 2. Diagnosis of HIV infection in women may be overlooked, as the clinical signs that routinely trigger the suspicion of HIV illness in men are often interpreted to reflect depression or psychological factors, such as stress or overwork, rather than raise the suspicion of HIV infection in women. 3. Understanding a woman's illness cognition is an important component of designing strategies that can enhance coping. The picture a woman generates regarding her illness is a composite of her experiences and responses, and determines to a large extent what she will do in response to her illness.  相似文献   
60.
A large number of states adopted tort reforms in the mid-1980s to limit the dramatic surge in insurance losses and premiums. Evidence based on liability insurance data by state indicates that these reforms substantially influenced general liability insurance. The levels of losses, premiums, and loss ratios (a measure of insurance profitability) all reflected the impact of the reforms. The large-scale reform efforts in 1986 were particularly influential. Medical malpractice insurance was much less sensitive to the reform efforts.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号