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   7672篇
  免费   181篇
  国内免费   1篇
管理学   1048篇
民族学   33篇
人口学   779篇
丛书文集   32篇
理论方法论   689篇
综合类   91篇
社会学   3742篇
统计学   1440篇
  2023年   40篇
  2020年   97篇
  2019年   146篇
  2018年   177篇
  2017年   256篇
  2016年   183篇
  2015年   127篇
  2014年   165篇
  2013年   1370篇
  2012年   246篇
  2011年   210篇
  2010年   148篇
  2009年   140篇
  2008年   150篇
  2007年   149篇
  2006年   175篇
  2005年   158篇
  2004年   154篇
  2003年   141篇
  2002年   157篇
  2001年   170篇
  2000年   173篇
  1999年   175篇
  1998年   142篇
  1997年   138篇
  1996年   130篇
  1995年   116篇
  1994年   116篇
  1993年   117篇
  1992年   122篇
  1991年   133篇
  1990年   133篇
  1989年   146篇
  1988年   91篇
  1987年   115篇
  1986年   97篇
  1985年   117篇
  1984年   100篇
  1983年   108篇
  1982年   83篇
  1981年   87篇
  1980年   79篇
  1979年   84篇
  1978年   85篇
  1977年   65篇
  1976年   70篇
  1975年   63篇
  1974年   59篇
  1973年   50篇
  1971年   42篇
排序方式: 共有7854条查询结果,搜索用时 890 毫秒
31.
本文为第三届“文化与城市可持续发展”国际会议的主题发言。本文介绍了会议背景 ,论述了文化及其与可持续发展的关系 ,都市化进程及其发展方向等问题 ,并着重阐述了本次会议的主题即“城市可持续发展中的文化指标” ,确立了本次会议的总体基调和基本政策  相似文献   
32.
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   
33.
34.
State governments exercise significant powers to regulate the economic and social activities of resident aliens. We review the laws of the six leading states of immigrant settlement regulating access of noncitizens to 23 occupations, updating existing studies from 1946–77. Citizenship requirements for these occupations have plummeted, a change we attribute to federal court decisions, advisory opinions of state attorneys general, and state legislative and administrative action. There are numerous additional citizenship requirements in the statutes of the six states, although these appear to be poorly enforced. The authority of states to regulate their political communities is the most important remaining constitutionally valid basis of citizenship requirements. States define their political community broadly, leading to questionable exclusions of noncitizens from important activities.  相似文献   
35.
This article explores two problems analysts face in determining how to estimate values for children's health and safety risk reductions. The first addresses the question: Do willingness‐to‐pay estimates for health risk changes differ across children and adults and, if so, how? To answer this question, the article first examines the potential effects of age and risk preferences on willingness to pay. A summary of the literature reporting empirical evidence of differences between willingness to pay for adult health and safety risk reductions and willingness to pay for health and safety risk reductions in children is also provided. The second dimension of the problem is a more fundamental issue: Whose perspective is relevant when valuing children's health effects—society's, children's, adults‐as‐children, or parents'? Each perspective is considered, followed ultimately by the conclusion that adopting a parental perspective through an intrahousehold allocation model seems closest to meeting the needs of the estimation problem at hand. A policy example in which the choice of perspective affects the outcome of a regulatory benefit‐cost analysis rounds out the article and emphasizes the importance of perspective.  相似文献   
36.
Conditional cash transfers are a departure from more traditional approaches to social assistance that represents an innovative and increasingly popular channel for the delivery of social services. Conditional cash transfers provide money to poor families contingent upon certain behaviour, usually investments in human capital such as sending children to school or bringing them to health centres on a regular basis. They seek both to address traditional short-term income support objectives and promote the longer-term accumulation of human capital by serving as a demand-side complement to the supply of health and education services. Evaluation results reveal that this innovative design has been quite successful in addressing many of the failures in delivering social assistance such as poor poverty targeting, disincentive effects and limited welfare impacts. There is clear evidence of success from the first generation of programmes in Brazil, Colombia, Mexico and Nicaragua in increasing enrolment rates, improving preventive healthcare and raising household consumption. Despite this promising evidence, many questions remain unanswered about conditional cash transfer programmes, including the replicability of their success under different  相似文献   
37.
This study concerned the immunological correlates of stress and work. Self reported stress, emotional state, ego-strength, and defensiveness were examined in relation to measures of cellular immunity (T-cell response to Con A and number of T4 and T8 cells) and humoral immunity (concentrations of immunoglobulins and complement components in plasma) in a group of 96 Norwegian female bank employees. The analyses showed that workload, the stress factor with the highest group mean, was associated with number of T-cells, while strain due to body posture during work was related to concentrations of IgM and C3. Further, depression was significantly correlated with IgM concentration and T-cell number, and anxiety with C3 concentration. T-cell activity was the immunological parameter most consistently associated with psychological well-being, showing positive correlations with defensiveness and ego-strength and negative correlations with anxiety and depression. In conclusion, T-cell number and concentrations of IgM and C3 were sensitive to both work-related stress experience and emotional distress. Coping abilities, indicated by the MMPI Ego-strength scale and emotional distress, were reflected in T-cell activity; insufficient coping was associated with low T-cell activity.  相似文献   
38.
39.
Certain issues that are being debated in psychology in a post-apartheid South Africa are discussed, namely the development of professional organizations, indigenous healing and psychology, the psychometric movement, and forms of methodological inquiry. It is argued that South African psychology is striving to become more appropriate to the majority of its peoples, whether it be on the professional or research fronts. There is a desire to develop indigenous epistemologies and not to become excessively reliant on Euro-American epistemological traditions. Psychology is struggling to make mental health resources available to all South Africans.  相似文献   
40.
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