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   28117篇
  免费   485篇
管理学   3368篇
民族学   145篇
人才学   6篇
人口学   2500篇
丛书文集   163篇
教育普及   5篇
理论方法论   2547篇
现状及发展   1篇
综合类   336篇
社会学   14303篇
统计学   5228篇
  2023年   142篇
  2021年   147篇
  2020年   403篇
  2019年   622篇
  2018年   652篇
  2017年   920篇
  2016年   651篇
  2015年   505篇
  2014年   633篇
  2013年   5096篇
  2012年   885篇
  2011年   833篇
  2010年   646篇
  2009年   600篇
  2008年   687篇
  2007年   692篇
  2006年   664篇
  2005年   602篇
  2004年   575篇
  2003年   523篇
  2002年   548篇
  2001年   684篇
  2000年   597篇
  1999年   601篇
  1998年   446篇
  1997年   395篇
  1996年   457篇
  1995年   453篇
  1994年   443篇
  1993年   422篇
  1992年   472篇
  1991年   468篇
  1990年   455篇
  1989年   427篇
  1988年   406篇
  1987年   366篇
  1986年   359篇
  1985年   387篇
  1984年   383篇
  1983年   332篇
  1982年   285篇
  1981年   244篇
  1980年   264篇
  1979年   266篇
  1978年   224篇
  1977年   216篇
  1976年   192篇
  1975年   192篇
  1974年   146篇
  1973年   122篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
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   
83.
Despite extensive study concerning involuntary departures by U.S. House members, little has been said about voluntary departures from the House–-quit behavior. This paper has three primary purposes: (1) to establish a theoretical framework that models the full range of choices a representative faces in any given term, (2) to measure the impact of different variables that affect representatives' quit behavior, and (3) to explain why Republicans have been more likely to pursue higher office than their Democratic colleagues.  相似文献   
84.
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   
85.
Readers wishing to correspond with Mr. O’Connell may do so through the editorial office of the Journal.  相似文献   
86.
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   
87.
88.
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   
89.
This paper describes the lifestyle model of gambling behavior in which compulsive gambling behavior is conceptualized as a lifestyle characterized by pseudoresponsibility, self-ascension, hypercompetitiveness, and social rule breaking/bending/ twisting. The underlying premise of this theory is that gambling behavior takes on the appearance of a lifestyle when it is viewed by the individual as a viable means of enhancing self-worth, minimizing personal insecurity, and controlling fear. Three primary areas of theoretical and research interest are covered in this paper: (1) the theoretical underpinnings of lifestyle theory; (2) the individual components (conditions, choice, cognition) of a gambling lifestyle; and (3) the developmental progression of a gambling lifestyle.The author would like to thank Henry Lesieur and anonymous reviewers of earlier versions of this paper for their helpful comments. The assertions and opinions contained herein are the private views of the author and should not be construed as official or as reflecting the views of the Federal Bureau of Prisons or United States Department of Justice.  相似文献   
90.
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