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   16260篇
  免费   298篇
  国内免费   2篇
管理学   2302篇
民族学   96篇
人才学   5篇
人口学   1493篇
丛书文集   105篇
理论方法论   1755篇
综合类   274篇
社会学   8295篇
统计学   2235篇
  2021年   73篇
  2020年   234篇
  2019年   362篇
  2018年   355篇
  2017年   499篇
  2016年   403篇
  2015年   306篇
  2014年   396篇
  2013年   2636篇
  2012年   512篇
  2011年   497篇
  2010年   394篇
  2009年   407篇
  2008年   409篇
  2007年   454篇
  2006年   402篇
  2005年   444篇
  2004年   453篇
  2003年   348篇
  2002年   394篇
  2001年   417篇
  2000年   343篇
  1999年   327篇
  1998年   283篇
  1997年   254篇
  1996年   241篇
  1995年   236篇
  1994年   232篇
  1993年   243篇
  1992年   223篇
  1991年   228篇
  1990年   205篇
  1989年   201篇
  1988年   199篇
  1987年   192篇
  1986年   168篇
  1985年   210篇
  1984年   213篇
  1983年   194篇
  1982年   178篇
  1981年   137篇
  1980年   156篇
  1979年   157篇
  1978年   139篇
  1977年   127篇
  1976年   132篇
  1975年   140篇
  1974年   124篇
  1973年   98篇
  1972年   77篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Longitudinal data often contain missing observations, and it is in general difficult to justify particular missing data mechanisms, whether random or not, that may be hard to distinguish. The authors describe a likelihood‐based approach to estimating both the mean response and association parameters for longitudinal binary data with drop‐outs. They specify marginal and dependence structures as regression models which link the responses to the covariates. They illustrate their approach using a data set from the Waterloo Smoking Prevention Project They also report the results of simulation studies carried out to assess the performance of their technique under various circumstances.  相似文献   
42.
The paradigm in disability supports is shifting away from institutional services and professional control towards self-determination and community involvement of people with disabilities. The assumption that the best way to provide disability supports is for government to give money to agencies or services, rather than directly to people with disabilities and their support networks, is being challenged. This article reports on findings and themes from a Canadian study that investigated individualised funding projects from different parts of the world. Ten of fifteen of the most 'promising initiatives' were selected for more detailed study and analysis. Projects analysed were from Canada, the US, and Australia. Themes emerging from the study included the fact that values and principles mattered, a policy framework provided coherence and equity, infrastructure supports for individuals were separate from service system, the facilitator-broker role differed from case management, allocation of individualised funds was designed to be equitable and account able to the funder and person, and a 'learn as you go' philosophy maximised positive outcomes. This research project demonstrates that individualised support and funding, when embedded in the new paradigm of disability and community, builds capacity of individuals, families, and communities.  相似文献   
43.
Boundary Spaces     
While shows like The X-Files and 24 have merged conspiracy theories with popular science (fictions), some video games have been pushing the narrative even further. Electronic Art's Majestic game was released in July 2001 and quickly generated media buzz with its unusual multi-modal gameplay. Mixing phone calls, faxes, instant messaging, real and "fake' websites, and email, the game provides a fascinating case of an attempt at new directions for gaming communities. Through story, mode of playing, and use of technology, Majestic highlights the uncertain status of knowledge, community and self in a digital age; at the same time, it allows examination of alternative ways of understanding games' role and purpose in the larger culture. Drawing on intricate storylines involving government conspiracies, techno-bio warfare, murder and global terror, players were asked to solve mysteries in the hopes of preventing a devastating future of domination. Because the game drew in both actual and Majestic-owned/-designed websites, it constantly pushed those playing the game right to borders where simulation collides with " factuality'. Given the wide variety of "legitimate' conspiracy theory, alien encounters and alternative science web pages, users often could not distinguish when they were leaving the game's pages and venturing into " real' World Wide Web sites. Its further use of AOL's instant messenger system, in which gamers spoke not only to bots but to other players, pushed users to evaluate constantly both the status of those they were talking to and the information being provided. Additionally, the game required players to occupy unfamiliar subject positions, ones where agency was attenuated, and which subsequently generated a multi-layered sense of unease among players. This mix of authentic and staged information in conjunction with technologically mediated roles highlights what are often seen as phenomenon endemic to the Internet itself; that is, the destabilization of categories of knowing, relating, and being.  相似文献   
44.
45.
46.
Determining the size and demographiccharacteristics of substance abuse populationsis extremely important for implementing publicpolicies aimed at the control of substanceabuse. Such information not only assists in theallocation of limited treatment resources bythe state, but also in the monitoring ofsubstance abuse trends over time and in theevaluation of innovative policy initiatives. Inthis study, we develop three composite measuresof treatment need. We then use these measuresto estimate treatment need for alcohol abuseand for controlled substance abuse within eachof Florida's 67 counties. This study providesan important empirical component of communityplanning, quantifying and, to a limited degree,specifying the level of need for the substanceabuse treatment of community residents. Anadditional benefit is the development of a costeffective and unobtrusive methodology fordetermining empirically when levels of need arechanging so that treatment levels can beadjusted accordingly. With proper use,policymakers can readily employ the methodologydeveloped in this study in Florida andelsewhere to make better-informed decisions inthe allocation of finite substance abusetreatment resources.  相似文献   
47.
48.
49.
Career and personal counseling are inextricably intertwined. Career problems have a strong emotional component. Career indecision and procrastination may be better interpreted as zeteophobia, the fear of career exploration. Trait and factor theory pictures career counseling as unrealistically simplistic and leads neophytes to view it as boring. Training all counselors to integrate career and personal counseling would lead to better service for clients.  相似文献   
50.
In the development of many diseases there are often associated random variables which continuously reflect the progress of a subject towards the final expression of the disease (failure). At any given time these processes, which we call stochastic covariates, may provide information about the current hazard and the remaining time to failure. Likewise, in situations when the specific times of key prior events are not known, such as the time of onset of an occult tumour or the time of infection with HIV-1, it may be possible to identify a stochastic covariate which reveals, indirectly, when the event of interest occurred. The analysis of carcinogenicity trials which involve occult tumours is usually based on the time of death or sacrifice and an indicator of tumour presence for each animal in the experiment. However, the size of an occult tumour observed at the endpoint represents data concerning tumour development which may convey additional information concerning both the tumour incidence rate and the rate of death to which tumour-bearing animals are subject. We develop a stochastic model for tumour growth and suggest different ways in which the effect of this growth on the hazard of failure might be modelled. Using a combined model for tumour growth and additive competing risks of death, we show that if this tumour size information is used, assumptions concerning tumour lethality, the context of observation or multiple sacrifice times are no longer necessary in order to estimate the tumour incidence rate. Parametric estimation based on the method of maximum likelihood is outlined and is applied to simulated data from the combined model. The results of this limited study confirm that use of the stochastic covariate tumour size results in more precise estimation of the incidence rate for occult tumours.  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