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   23509篇
  免费   410篇
管理学   2919篇
民族学   131篇
人才学   8篇
人口学   2226篇
丛书文集   141篇
教育普及   2篇
理论方法论   2302篇
现状及发展   1篇
综合类   281篇
社会学   11713篇
统计学   4195篇
  2023年   111篇
  2021年   107篇
  2020年   362篇
  2019年   543篇
  2018年   531篇
  2017年   758篇
  2016年   578篇
  2015年   439篇
  2014年   550篇
  2013年   3950篇
  2012年   793篇
  2011年   700篇
  2010年   573篇
  2009年   556篇
  2008年   637篇
  2007年   634篇
  2006年   583篇
  2005年   586篇
  2004年   613篇
  2003年   544篇
  2002年   558篇
  2001年   602篇
  2000年   481篇
  1999年   484篇
  1998年   413篇
  1997年   369篇
  1996年   366篇
  1995年   356篇
  1994年   335篇
  1993年   337篇
  1992年   354篇
  1991年   366篇
  1990年   314篇
  1989年   309篇
  1988年   303篇
  1987年   271篇
  1986年   266篇
  1985年   301篇
  1984年   284篇
  1983年   283篇
  1982年   231篇
  1981年   197篇
  1980年   215篇
  1979年   210篇
  1978年   180篇
  1977年   180篇
  1976年   161篇
  1975年   152篇
  1974年   125篇
  1973年   101篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure.  相似文献   
62.
Racial differences in urban neighboring   总被引:2,自引:0,他引:2  
Despite mixed expectations generated by existing theories and evidence, this analysis documents clear racial differences in urban neighboring behavior. Using data from a survey of Nashville, Tennessee, residents, we show that blacks interact with their neighbors more often than whites do, and in a greater variety of ways. The only noteworthy similarity between the two groups is the positive impact of neighboring on feelings of community affect. Overall, our results support the view that neighbor relations — like other kinds of informal participation — have helped blacks cope with constrained social opportunities and provided them with access to resources unavailable through formal institutional channels.Revised version of a paper presented at the annual meeting of the American Sociological Association, San Francisco, August 1989.  相似文献   
63.
Readers wishing to correspond with Mr. O’Connell may do so through the editorial office of the Journal.  相似文献   
64.
Differential participation after recruitment remains a black box in the social-movement and voluntary-association literatures. This paper identifies several dimensions of membership participation in a professional social-movement organization (SMO) with a national membership and analyzes the determinants of differential involvement in these forms. In general, members' ideological beliefs, social and organizational ties, perceptions about their SMO, and communication with SMO officials all predict participation across the various forms. Our findings extend previous work on differential participation in three ways. First, we statistically isolate cultural dimensions of postrecruitment participation and, in so doing, complement recent ethnographic research. Second, our findings suggest that the distinct dimensions of external and internal participation found by Knoke (1988) in a national sample of voluntary associations may not generalize to national SMOs studied individually. Third, our results indicate that models combining ideological and microstructural factors should explain the multiple forms of participation in SMOs lacking these distinct dimensions.  相似文献   
65.
Abstract Agroforestry, the practice of raising crops and trees together in ways that are mutually beneficial, provides farmers with an alternative to more conventional farming practices. In this paper, we apply Bourdieu's concepts of “field” and “habitus” in an attempt to better understand the practice of farming and the role that agroforestry may have in farming systems. Analysis is based on qualitative and quantitative interviews of farmers and other key informants in two regions, Fox‐Wyaconda Watershed in northeast Missouri and Scott County in southeast Missouri. Within the field of farming, farmers emphasized the importance of economic, family and rental relations. Important habitus considerations include different interpretations of what constitutes farming and what constitutes forestry. Based on Bourdieu's theoretical framework, we offer three alternative paths of social change that may lead to more widespread utilization of agroforestry.  相似文献   
66.
We analyse whether the psychological pricing in the private sector has a public sector counterpart in tax policy. Analysing the main theoretical arguments for the existence of price points, and applying them to the public sector, suggests that psychological taxing reveals itself by the use of non-0 ending tax rates. The tax rate endings of the local income taxes, which are set by 308 Flemish municipalities in the fiscal year 1998, suggests the presence of psychological taxing. Non-0 endings occur more frequently in municipalities where demand for public policy is more elastic (and where, therefore, the benefits to the politicians from setting a tax just below a tax point is higher). The pre-tax income inequality and the level of the tax rate positively affect psychological taxing. The latter effect is reinforced in those municipalities where the existing tax rate is above the average tax rate in neighbouring municipalities and below their neighbours’ minimum, although this effect has a limited effect and is offset the further below the minimum the tax is set.  相似文献   
67.
This paper reports on the organization of care management froma longitudinal study of community care for people resettledfrom long-stay learning disability and psychiatric hospitals.The findings from a 12-year follow-up of care management arrangementsin 12 learning disability and eight mental health study siteservices are described. The diversity of care management arrangementsfound at earlier points in the evaluation remained evident.Also, many of the former ‘care in the community’service users were excluded from mainstream care managementarrangements in their localities. The difficulty of developingperson-centred arrangements in learning disability and the lackof integration of the Care Programme Approach and care managementwere evident. The findings and observations are placed in thewider policy and practice context, with suggestions for takingcare management forward nationally and locally.  相似文献   
68.
69.
In this paper, the history of atmospheric science is traced, from the earliest discussions from meteorologists, and the first meetings to describe this new research area. The development of atmospheric science proceeded in three phases with each phase being marked by the attempt to organize resources, and bring into the atmospheric science network, scientists from other fields. I argue here that this construction of a science provides evidence of the social nature of science as well as the importance of organizations to the creation of a science.  相似文献   
70.
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