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   7512篇
  免费   180篇
  国内免费   1篇
管理学   1063篇
民族学   44篇
人口学   644篇
丛书文集   22篇
理论方法论   634篇
综合类   70篇
社会学   3217篇
统计学   1999篇
  2023年   44篇
  2021年   49篇
  2020年   108篇
  2019年   172篇
  2018年   187篇
  2017年   275篇
  2016年   193篇
  2015年   126篇
  2014年   200篇
  2013年   1432篇
  2012年   225篇
  2011年   229篇
  2010年   171篇
  2009年   181篇
  2008年   192篇
  2007年   175篇
  2006年   192篇
  2005年   177篇
  2004年   151篇
  2003年   135篇
  2002年   164篇
  2001年   199篇
  2000年   199篇
  1999年   183篇
  1998年   135篇
  1997年   123篇
  1996年   104篇
  1995年   92篇
  1994年   137篇
  1993年   97篇
  1992年   124篇
  1991年   128篇
  1990年   115篇
  1989年   102篇
  1988年   88篇
  1987年   89篇
  1986年   90篇
  1985年   87篇
  1984年   91篇
  1983年   68篇
  1982年   70篇
  1981年   48篇
  1980年   59篇
  1979年   62篇
  1978年   48篇
  1977年   48篇
  1976年   38篇
  1975年   47篇
  1974年   40篇
  1971年   25篇
排序方式: 共有7693条查询结果,搜索用时 228 毫秒
521.
Wooddell V  Kaplan KJ 《Omega》1999,40(1):43-60
Ninety-six students were presented with eighteen different vignettes describing different types of active and passive observed suicide, assisted suicide, and euthanasia. Attitudes regarding the morality and desired legality of each situation were measured. Results indicated that the interaction between the doctor and the patient, and, to a lesser extent, the active or passive nature of the agent of death, were more important than the actual actions of the doctor in allowing or causing death to occur.  相似文献   
522.
Hammitt  James K.  Belsky  Eric S.  Levy  Jonathan I.  Graham  John D. 《Risk analysis》1999,19(6):1037-1058
Residential building codes intended to promote health and safety may produce unintended countervailing risks by adding to the cost of construction. Higher construction costs increase the price of new homes and may increase health and safety risks through income and stock effects. The income effect arises because households that purchase a new home have less income remaining for spending on other goods that contribute to health and safety. The stock effect arises because suppression of new-home construction leads to slower replacement of less safe housing units. These countervailing risks are not presently considered in code debates. We demonstrate the feasibility of estimating the approximate magnitude of countervailing risks by combining the income effect with three relatively well understood and significant home-health risks. We estimate that a code change that increases the nationwide cost of constructing and maintaining homes by $150 (0.1% of the average cost to build a single-family home) would induce offsetting risks yielding between 2 and 60 premature fatalities or, including morbidity effects, between 20 and 800 lost quality-adjusted life years (both discounted at 3%) each year the code provision remains in effect. To provide a net health benefit, the code change would need to reduce risk by at least this amount. Future research should refine these estimates, incorporate quantitative uncertainty analysis, and apply a full risk-tradeoff approach to real-world case studies of proposed code changes.  相似文献   
523.
The authors use longitudinal data from the National Longitudinal Survey of Youth to investigate whether the wage trajectories of male high school dropouts are affected by the acquisition of the General Educational Development (GED) credential, by postsecondary education, and by training. The authors show that acquisition of the GED results in wage increases for dropouts who left school with weak skills, but not for dropouts who left high school with stronger skills. College and training provided by employers are associated with higher wages for male dropouts.  相似文献   
524.
"Debates about United States border control policies have generally ignored the human costs of undocumented migration. We focus attention on these costs by estimating the number, causes and location of migrant deaths at the southwest border of the United States between 1993 and 1997.... Deaths from hyperthermia, hypothermia and dehydration increased sharply from 1993 to 1997 as intensified border enforcement redirected undocumented migration flows from urban crossing points to more remote crossing areas where the migrants are exposed to a greater risk of death."  相似文献   
525.
526.
Bayesian robustness is studied for ε-contamination classes of prior distributions. Nonparametric classes of contsminations such as the class of all unimodal spherically symmetric densities are considered here. Posterior φ-divergence and its curvature are used to measure the sensitivity of priors on the resulting posterior densities. Examples are provided to illustrate our results.  相似文献   
527.
This article outlines the development of an interactive video system designed to demonstrate differential approaches to family therapy using identical therapy situations. The primary purpose of the project is to resolve some of the confusion many novice family therapists experience while being exposed to the numerous family therapy approaches. Technical aspects of the interactive video system are also outlined.  相似文献   
528.
529.
530.
Independent samples are drawn from control and treatment populations with normal and compound normal distributions respectively. We derive the locally best invariant (LBI) tests through Wijsman’s representation for the detection of mixture departures from the normal distribution. These tests may be viewed as tests for the equality of control and treatment populations. Further, they are optimally robust for the model considered by Durairajan and Raman (1994).  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