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121.
Daniel Aggio Olia Papacosta Lucy T. Lennon Sarah Ash Peter H. Whincup S. Goya Wannamethee Barbara J. Jefferis 《European review of aging and physical activity》2018,15(1):16
Background
Previous physical activity (PA) tracking studies have examined the stability of overall PA and/or PA types, but few have investigated how specific types of sport/exercise track over the life course. The aim of this study was to determine how specific sports/exercises in midlife track and predict future sport/exercise and PA in men transitioning to old age.Methods
Seven thousand seven hundred thirty-five men (aged 40–59?years) recruited in 1978–80 were followed up after 12, 16 and 20?years. At each wave men self-reported participation in sport/exercise. Frequent sport/exercise participants (>?1/month) reported the types of sport/exercise they engaged in. Men also reported total PA, health status, lifestyle behaviours and socio-demographic characteristics. Stability of each sport/exercise was assessed using kappa statistics and intraclass correlation coefficients. Logistic regression estimated the odds of participating in sport/exercise and being active at 20-year follow up according to specific types of sport/exercise in midlife.Results
Three thousand three hundred eighty-four men with complete data at all waves were included in analyses. Tracking of specific sports/exercises ranged from fair to substantial, with golf being the most common and most stable. Bowls was the most frequently adopted. Odds of participating in sport/exercise and being active in old age varied according to sport/exercise types in midlife. Golf and bowls in midlife were the strongest predictors of sport/exercise participation in old age. Golf, cricket and running/jogging in midlife were among the strongest predictors of being active in old age. Compared to participating in just one sport/exercise in midlife, sampling multiple sports/exercises was more strongly associated with sport/exercise participation and being active in old age.Conclusion
The stability of sport/exercise participation from midlife to old age varies by type. Specific sports/exercises in midlife may be more likely to predict future PA than others. However, participating in a range of sports/exercises may be optimal for preserving PA into old age.122.
123.
A common objective of cohort studies and clinical trials is to assess time-varying longitudinal continuous biomarkers as correlates of the instantaneous hazard of a study endpoint. We consider the setting where the biomarkers are measured in a designed sub-sample (i.e., case-cohort or two-phase sampling design), as is normative for prevention trials. We address this problem via joint models, with underlying biomarker trajectories characterized by a random effects model and their relationship with instantaneous risk characterized by a Cox model. For estimation and inference we extend the conditional score method of Tsiatis and Davidian (Biometrika 88(2):447–458, 2001) to accommodate the two-phase biomarker sampling design using augmented inverse probability weighting with nonparametric kernel regression. We present theoretical properties of the proposed estimators and finite-sample properties derived through simulations, and illustrate the methods with application to the AIDS Clinical Trials Group 175 antiretroviral therapy trial. We discuss how the methods are useful for evaluating a Prentice surrogate endpoint, mediation, and for generating hypotheses about biological mechanisms of treatment efficacy. 相似文献
124.
Patient heterogeneity may complicate dose‐finding in phase 1 clinical trials if the dose‐toxicity curves differ between subgroups. Conducting separate trials within subgroups may lead to infeasibly small sample sizes in subgroups having low prevalence. Alternatively,it is not obvious how to conduct a single trial while accounting for heterogeneity. To address this problem,we consider a generalization of the continual reassessment method on the basis of a hierarchical Bayesian dose‐toxicity model that borrows strength between subgroups under the assumption that the subgroups are exchangeable. We evaluate a design using this model that includes subgroup‐specific dose selection and safety rules. A simulation study is presented that includes comparison of this method to 3 alternative approaches,on the basis of nonhierarchical models,that make different types of assumptions about within‐subgroup dose‐toxicity curves. The simulations show that the hierarchical model‐based method is recommended in settings where the dose‐toxicity curves are exchangeable between subgroups. We present practical guidelines for application and provide computer programs for trial simulation and conduct. 相似文献
125.
Agreement and discrepancy between children,parents, and social workers on school‐based effort avoidance in child welfare services 下载免费PDF全文
Hanna Maria Weber Franz Petermann Stefan Rücker Peter Büttner 《Child & Family Social Work》2017,22(4):1431-1439
A multiperspective approach is beneficial for obtaining reliable and multifaceted pictures of child behaviour problems. The goal of the present study is to examine interrater agreement on school‐based effort avoidance between children receiving child welfare services, parents, and social workers. Given previous findings, interrater agreement is expected to be low. Self‐reported data on school‐based effort avoidance were gathered for children and adolescents in child welfare services. Additionally, social workers (using the Teacher‐Report Checklist for social and learning behaviour) and parents (using the parallel version of the self‐rating questionnaire on school‐based effort avoidance) were asked to complete an external assessment tool to compare children's perspectives with the ratings of significant adults. The results confirmed significant discrepancies between parents' and children's ratings on effort avoidance tendencies. Furthermore, there were only small to moderate correlations between children's self‐ratings and the adults' assessments; however, the consensus between adults was higher than the interrater agreement between children and social workers. Discrepancies in ratings from multiple informants underline the importance of integrating multiple perspectives, especially children's perspectives, in the diagnostic process in order to plan and adapt appropriate care and treatment. 相似文献
126.
127.
Peter Van Aelst Patrick van Erkel Evelien D’heer Raymond A. Harder 《Information, Communication & Society》2017,20(5):715-732
Attention in the mass media is seen as crucial for electoral success. However, most ordinary candidates hardly get any attention in the news. With social media outlets becoming ever more popular, the question is whether the overall asymmetry in attention for candidates still holds today. Do candidates who dominate the traditional media during the campaign also dominate the social media? Or can candidates make up for a lack of mass media coverage by attracting attention on these new media platforms? This paper aims to answer these questions by pairing Twitter activity and Twitter popularity with newspaper attention for a large number of individual candidates in the 2014 Belgian election campaign. We expand the normalization versus equalization debate by not only looking at how much a new medium is used, but also at its success in terms of popularity and audience reach. Our findings show that the two platforms are indeed related, mainly because a small political elite dominates both old and new media. Twitter popularity and Twitter activity (albeit to a lesser extent) are higher among powerful politicians. We elaborate on why these findings are so much in line with the normalization hypothesis. 相似文献
128.
129.
Although subprime mortgage lending and unemployment were largely responsible for the wave of foreclosures during the Great Recession, additional sources of financial risk may have exacerbated the crisis. We hypothesize that many parents sending children to college were financially overextended and vulnerable to foreclosure as the economy contracted. With commuting zone panel data from 2006 to 2011, we show that increasing rates of college attendance across the income distribution in one year predict a foreclosure rate increase in subsequent years, net of fixed characteristics and changes in employment, refinance debt, house prices, and 19-year-old population size. We find similar evidence of college-related foreclosure risk using longitudinal household data from the Panel Study of Income Dynamics. Our findings uncover a previously overlooked dimension of the foreclosure crisis, and highlight mortgage insecurity as an inadvertent consequence of parental investment in higher education. 相似文献
130.
Irga Peter J. Burchett Margaret D. O’Reilly Gabe Torpy Fraser R. 《Urban Ecosystems》2016,19(2):885-898
Urban Ecosystems - Many street trees in urban areas are deciduous and drop leaves during autumn. These leaves are a potential growing substrate for fungi, which when aerosolized and inhaled, can... 相似文献