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   36095篇
  免费   1084篇
  国内免费   2篇
管理学   4979篇
民族学   172篇
人才学   1篇
人口学   3367篇
丛书文集   150篇
教育普及   3篇
理论方法论   3292篇
现状及发展   1篇
综合类   418篇
社会学   17960篇
统计学   6838篇
  2023年   204篇
  2021年   243篇
  2020年   579篇
  2019年   833篇
  2018年   1011篇
  2017年   1331篇
  2016年   1027篇
  2015年   734篇
  2014年   979篇
  2013年   6105篇
  2012年   1264篇
  2011年   1215篇
  2010年   887篇
  2009年   739篇
  2008年   931篇
  2007年   888篇
  2006年   909篇
  2005年   796篇
  2004年   786篇
  2003年   690篇
  2002年   745篇
  2001年   894篇
  2000年   847篇
  1999年   778篇
  1998年   605篇
  1997年   539篇
  1996年   549篇
  1995年   539篇
  1994年   489篇
  1993年   505篇
  1992年   583篇
  1991年   565篇
  1990年   531篇
  1989年   500篇
  1988年   490篇
  1987年   425篇
  1986年   432篇
  1985年   480篇
  1984年   450篇
  1983年   409篇
  1982年   349篇
  1981年   293篇
  1980年   298篇
  1979年   341篇
  1978年   286篇
  1977年   260篇
  1976年   209篇
  1975年   227篇
  1974年   195篇
  1973年   167篇
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
161.
162.
163.
Relations between grandmother and partner involvement (coresidence, social support, child care) and Puerto Rican adolescent mothers' parenting behaviors were examined. Few associations between grandmother involvement and behavior emerged, and these were moderated by coresidence. In contrast, partner involvement showed a number of significant (positive) direct and moderated relations with behavior. For both providers, the direction of the relations between social support and behavior during teaching was the opposite depending on coresidence: Greater social support was related to the display of more positive behavior among coresiding mothers but to less competent behavior among non‐coresiding mothers. The relations between child care support and behavior differed across providers. For grandmothers, greater child care was related to less positive behavior during teaching among coresiding mothers but to more competent behavior among non‐coresiding mothers. For partners, greater child care was more strongly related to positive behavior during play among non‐coresiding than coresiding mothers. Results are discussed in light of Latino cultural values, developmental issues, and implications for intervention.  相似文献   
164.
Silphids in urban forests: Diversity and function   总被引:2,自引:0,他引:2  
Wolf  Jordan M.  Gibbs  James P. 《Urban Ecosystems》2004,7(4):371-384
Many ecologists have examined the process of how urbanization reduces biological diversity but rarely have its ecological consequences been assessed. We studied forest-dwelling burying beetles (Coleoptera: Silphidae)—a guild of insects that requires carrion to complete their life cycles—along an urban-rural gradient of land use in Maryland. Our objective was to determine how forest fragmentation associated with urbanization affects (1) beetle community diversity and structure and (2) the ecological function provided by these insects, that is, decomposition of vertebrate carcasses. Forest fragmentation strongly reduced burying beetle diversity and abundance, and did so far more pervasively than urbanization of the surrounding landscape. The likelihood that beetles interred experimental baits was a direct, positive function of burying beetle diversity. We conclude that loss of burying beetle diversity resulting from forest fragmentation could have important ecological consequences in urban forests.  相似文献   
165.
166.
Banks winners in tournaments are difficult to recognize   总被引:1,自引:0,他引:1  
Given a tournament T, a Banks winner of T is the top vertex of any maximal (with respect to inclusion) transitive subtournament of T. In this technical note, we show that the problem of deciding whether some fixed vertex v is a Banks winner for T is NP-complete. Received: 22 February 2002/Accepted: 20 June 2002 Supported by the START program Y43-MAT of the Austrian Ministry of Science. I would like to thank two thank the referees for a careful reading of the paper, for helpful remarks, and for many suggestions how to improve the presentation.  相似文献   
167.
We re-evaluate Andreu and Spanos's findings in favour of trend stationarity by considering the extended Nelson-Plosser data set. This expanded (to 1988) data set includes a period of rather different behaviour compared with the original Nelson-Plosser data used by Andreou and Spanos. We find that Andreou and Spanos's models (with only minor adjustments) exhibit remarable stability over this extended period, and indicate that their conclusions are more robust than they have shown.  相似文献   
168.
169.
Using findings from a study of the world of the wives of professional athletes, this article explores the complex motivations for and displays of trust, rapport, and group acceptance during ethnographic research. Episodic exchanges between a male ethnographer and female collaborators revealed subtle issues of gender and perceived relative worth. This article proposes the outsider strategy of “muted masculinity” as a means of exploring ethnographic issues in which the boundaries between insiders and outsiders are uncertain.  相似文献   
170.
Using an experimental design, this research examines the effect of the nation's first family cap on the births, abortions, and contraception use of over 8,000 women receiving public assistance in New Jersey. The family cap denies additional cash benefits to children conceived while the mother is receiving public assistance. Our research shows that a targeted welfare benefit manipulation does influence fertility behavior; however, the effect is conditioned by race. We find that Black women in the experimental group have a 21% lower birth rate and a 32% higher abortion rate than Black women in the control group. We do not find a birth effect for Hispanic or White women. We discuss the policy implications of the effects of a segmented family cap.  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