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   1138篇
  免费   33篇
管理学   196篇
民族学   6篇
人口学   113篇
丛书文集   2篇
理论方法论   107篇
综合类   11篇
社会学   601篇
统计学   135篇
  2023年   16篇
  2022年   12篇
  2021年   10篇
  2020年   32篇
  2019年   38篇
  2018年   48篇
  2017年   61篇
  2016年   57篇
  2015年   29篇
  2014年   48篇
  2013年   153篇
  2012年   42篇
  2011年   50篇
  2010年   41篇
  2009年   36篇
  2008年   44篇
  2007年   39篇
  2006年   28篇
  2005年   32篇
  2004年   37篇
  2003年   25篇
  2002年   21篇
  2001年   23篇
  2000年   19篇
  1999年   27篇
  1998年   17篇
  1997年   21篇
  1996年   12篇
  1995年   16篇
  1994年   13篇
  1993年   8篇
  1992年   7篇
  1991年   10篇
  1990年   9篇
  1989年   5篇
  1988年   6篇
  1987年   10篇
  1986年   7篇
  1985年   13篇
  1984年   10篇
  1983年   6篇
  1982年   6篇
  1981年   6篇
  1980年   3篇
  1976年   3篇
  1975年   2篇
  1971年   1篇
  1970年   4篇
  1967年   2篇
  1965年   1篇
排序方式: 共有1171条查询结果,搜索用时 15 毫秒
941.
Competing risk methods are time‐to‐event analyses that account for fatal and/or nonfatal events that may potentially alter or prevent a subject from experiencing the primary endpoint. Competing risk methods may provide a more accurate and less biased estimate of the incidence of an outcome but are rarely applied in cardiology trials. APEX investigated the efficacy of extended‐duration betrixaban versus standard‐duration enoxaparin to prevent a composite of symptomatic deep‐vein thrombosis (proximal or distal), nonfatal pulmonary embolism, or venous thromboembolism (VTE)–related death in acute medically ill patients (n = 7513). The aim of the current analysis was to determine the efficacy of betrixaban vs standard‐duration enoxaparin accounting for non‐VTE–related deaths using the Fine and Gray method for competing risks. The proportion of non‐VTE–related death was similar in both the betrixaban (133, 3.6%) and enoxaparin (136, 3.7%) arms, P = .85. Both the traditional Kaplan‐Meier method and the Fine and Gray method accounting for non‐VTE–related death as a competing risk showed equal reduction of VTE events when comparing betrixaban to enoxaparin (HR/SHR = 0.65, 95% 0.42‐0.99, P = 0.046). Due to the similar proportion of non‐VTE–related deaths in both treatment arms and the use of a univariate model, the Fine and Gray method provided identical results to the traditional Cox model. Using the Fine and Gray method in addition to the traditional Cox proportional hazards method can indicate whether the presence of a competing risk, which is dependent of the outcome, altered the risk estimate.  相似文献   
942.
ABSTRACT

In this paper, we present the extension of the analysis of time-dependent limiting characteristics the class of continuous-time birth and death processes defined on non-negative integers with special transitions from and to the origin. From the origin transitions can occur to any state. But being in any other state, besides ordinary transitions to neighboring states, a transition to the origin can occur. All possible transition intensities are assumed to be non-random functions of time and may depend on the state of the process. We improve previously known ergodicity and truncation bounds for this class of processes that were known only for the case when transitions from the origin decay exponentially (other intensities must have unique uniform upper bound). We show how the bounds can be obtained if the decay rate is slower than exponential. Numerical results are given in the queueing theory context.  相似文献   
943.
Reliable subnational mortality estimates are essential in the study of health inequalities within a country. One of the difficulties in producing such estimates is the presence of small populations among which the stochastic variation in death counts is relatively high, and thus the underlying mortality levels are unclear. We present a Bayesian hierarchical model to estimate mortality at the subnational level. The model builds on characteristic age patterns in mortality curves, which are constructed using principal components from a set of reference mortality curves. Information on mortality rates are pooled across geographic space and are smoothed over time. Testing of the model shows reasonable estimates and uncertainty levels when it is applied both to simulated data that mimic U.S. counties and to real data for French départements. The model estimates have direct applications to the study of subregional health patterns and disparities.  相似文献   
944.
Previous psychological and public health research has highlighted the impact of legal recognition of same-sex relationships on individual identity and mental health. Using a sample of U.S. sexual minority (N = 313) and heterosexual (N = 214) adults, participants completed a battery of mental health inventories prior to the nationwide legalization of same-sex marriage. Analyses of covariance (ANCOVAs) examining identity revealed sexual minority participants living in states where same-sex marriage was banned experienced significantly higher levels of internalized homonegativity than sexual minority participants living in states where same-sex marriage was legal, even after controlling for state-level political climate. Mental health ANCOVAs revealed sexual minority participants residing in states without same-sex marriage experienced greater anxiety and lower subjective wellbeing compared to sexual minority participants residing in states with same-sex marriage and heterosexual participants residing in states with or without same-sex marriage. Implications for public policy and future research directions are discussed.  相似文献   
945.
Only recently has research begun to investigate the interplay between work characteristics, leisure time physical activity (LTPA), health, and well-being. So far, however, this research lacks a theoretical foundation. In this article, we introduce the physical activity-mediated Demand–Control (pamDC) model as a new theoretical framework. The two key ideas of the pamDC model are (1) that job demands and job control affect LTPA and (2) that LTPA partially mediates the effects of job demands and job control on health and well-being. We present eight propositions explaining how work characteristics affect LTPA, health, and well-being. For each of these propositions, we discuss empirical evidence and theoretical foundations. We then sketch a research agenda on how to adopt the pamDC model as a new theoretical framework for future research linking work characteristics, LTPA, and health. Finally, we discuss the practical implications of our new model.  相似文献   
946.
For twenty years, technocratic planning and management approaches have dominated good‐governance reforms in developing countries. This is true even for newer ‘participatory’ and ‘citizen‐driven’ reforms that still struggle to engage with powerful informal forces affecting public service delivery. This article presents evidence from a case study of decentralised education‐system reform in Guinea, revealing a wide range of influential dynamics outside the technical realm. These corroborate the argument for ‘good‐fit’ alternatives to traditional governance approaches and concrete measures to better capture the constructive and disable the destructive effects of informality on development.  相似文献   
947.
Schools have been identified as playing a key role in supporting the children of prisoners. This paper reports on a study, which explored the support provision offered in schools to children who experience parental imprisonment. By interviewing school representatives, stakeholders, parents and children, we illustrate the support available in schools, the issues that arise and ways in which support provision can be strengthened. Our findings indicate that children of prisoners often constitute a ‘forgotten’ group in schools, and we suggest that an awareness of these children and the challenges they face needs to be raised amongst education practitioners and policy‐makers.  相似文献   
948.
Restrictions on monetary payout may promote player engagement in gambling as a form of entertainment rather than as a source of income. Our objective was to evaluate the effects of monetary prize magnitude upon gambling behaviour in a community sample, and the degree to which this association is moderated by gambling risk factors. One hundred and eighty-seven adults completed an online survey assessing motivation, impulsivity and affect. Participants were given a series of vignettes and asked to estimate how much they would gamble to win monetary prizes of increasing amounts with and without accrued gambling debt. Participants reported increased gambling in response to increased monetary payout. Debt moderated these outcomes, such that electronic gaming machine (EGM) and lottery expenditures and number of lottery games played decreased with increased debt; this effect was most pronounced at elevated monetary prizes. The association between duration of EGM play and monetary payout was moderated by gender only. Results suggest that self-reported gambling behaviours increased with monetary payout even across qualitatively different gambling products, and across gamblers with different motivations for gambling, levels of impulsivity, and negative affect. The restriction of monetary payouts warrants further research attention as a form of problem gambling prevention.  相似文献   
949.
950.
This article describes part of a mixed-method study investigating family and professional perspectives on home adaptations for disabled children. The methods were an online survey of staff involved in adaptations processes (n =39), semi-structured interviews with families with disabled children (n = 48) and an online survey for families (n = 16). One of the wider study’s recommendations was that families need to be enabled to engage with processes proactively. This article focuses on families’ experiences of the meaning attributed to adapting the home and highlights that, although satisfied with the completed adaptation, families were dissatisfied with the process they had been through. Thus, despite the need for the meaning of home being central to the adaptation process, families felt excluded from the process as it progressed. This had a negative impact on the continuing use of the adaptation and affected the meaning of home for families with a disabled child.  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