全文获取类型
收费全文 | 8813篇 |
免费 | 230篇 |
国内免费 | 1篇 |
专业分类
管理学 | 1186篇 |
民族学 | 50篇 |
人口学 | 883篇 |
丛书文集 | 44篇 |
理论方法论 | 791篇 |
现状及发展 | 1篇 |
综合类 | 102篇 |
社会学 | 4390篇 |
统计学 | 1597篇 |
出版年
2023年 | 52篇 |
2021年 | 55篇 |
2020年 | 128篇 |
2019年 | 180篇 |
2018年 | 218篇 |
2017年 | 302篇 |
2016年 | 223篇 |
2015年 | 162篇 |
2014年 | 195篇 |
2013年 | 1588篇 |
2012年 | 280篇 |
2011年 | 270篇 |
2010年 | 180篇 |
2009年 | 170篇 |
2008年 | 209篇 |
2007年 | 179篇 |
2006年 | 210篇 |
2005年 | 184篇 |
2004年 | 179篇 |
2003年 | 165篇 |
2002年 | 191篇 |
2001年 | 196篇 |
2000年 | 194篇 |
1999年 | 196篇 |
1998年 | 157篇 |
1997年 | 144篇 |
1996年 | 145篇 |
1995年 | 134篇 |
1994年 | 124篇 |
1993年 | 120篇 |
1992年 | 126篇 |
1991年 | 145篇 |
1990年 | 143篇 |
1989年 | 157篇 |
1988年 | 96篇 |
1987年 | 121篇 |
1986年 | 101篇 |
1985年 | 132篇 |
1984年 | 106篇 |
1983年 | 115篇 |
1982年 | 94篇 |
1981年 | 95篇 |
1980年 | 88篇 |
1979年 | 92篇 |
1978年 | 92篇 |
1977年 | 64篇 |
1976年 | 77篇 |
1975年 | 69篇 |
1974年 | 63篇 |
1973年 | 48篇 |
排序方式: 共有9044条查询结果,搜索用时 500 毫秒
351.
Control‐based imputation for sensitivity analyses in informative censoring for recurrent event data
下载免费PDF全文
![点击此处可从《Pharmaceutical statistics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Fei Gao Guanghan F. Liu Donglin Zeng Lei Xu Bridget Lin Guoqing Diao Gregory Golm Joseph F. Heyse Joseph G. Ibrahim 《Pharmaceutical statistics》2017,16(6):424-432
In clinical trials, missing data commonly arise through nonadherence to the randomized treatment or to study procedure. For trials in which recurrent event endpoints are of interests, conventional analyses using the proportional intensity model or the count model assume that the data are missing at random, which cannot be tested using the observed data alone. Thus, sensitivity analyses are recommended. We implement the control‐based multiple imputation as sensitivity analyses for the recurrent event data. We model the recurrent event using a piecewise exponential proportional intensity model with frailty and sample the parameters from the posterior distribution. We impute the number of events after dropped out and correct the variance estimation using a bootstrap procedure. We apply the method to an application of sitagliptin study. 相似文献
352.
353.
354.
355.
356.
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
![点击此处可从《Child & Family Social Work》网站下载免费的PDF全文](/ch/ext_images/free.gif)
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
357.
Caroline B. R. Evans Katie L. Cotter Paul R. Smokowski 《Child and Adolescent Social Work Journal》2017,34(6):543-555
Current research on how adolescents cope with bullying is primarily quantitative, examines youth in Grades 1 through 6, and neglects to specifically assess how victims of bullying cope with being bullied. The current qualitative study explored the coping strategies of 22 rural middle- and high-school youth victimized by bullying. Results indicated that youth report using an array of emotion focused coping strategies (an internal coping strategy that focuses on emotion regulation) and problem focused coping strategies (active behaviors that are aimed to decrease or eradicate the stressor). These coping strategies included help seeking, physical and verbal aggression, standing up for themselves, and prosocial bystander behavior. While the majority of coping strategies were similar between middle- and high-school participants, these groups reported utilizing verbal and physical aggression in different ways. Further, certain coping strategies, such as help seeking and lashing out with physical and verbal aggression, were utilized as both emotion- and problem-focused coping strategies. Implications are discussed. 相似文献
358.
Cyberbullying has been recognized as a serious social concern. Considering the varied contexts of online engagement by children and youth is increasingly necessary to adequately understand their experiences and the impact of their participation. An online context which requires further attention is gaming platforms, which are especially popular among boys. Methods: Using a theoretical approach of social dominance, this paper analyzed secondary data drawn from a mixed methods study of cyberbullying to investigate the prevalence and experience of gaming among a quantitative survey sample (n?=?670) of 4th, 7th, and 10th grade students, as well as the experience and impact of gaming on a qualitative interview sub-sample (n?=?57). Gaming prevalence rates are provided. Boys were significantly more likely to engage in internet gaming (though the effect size was small); χ² (1, n?=?669)?=?10.11, p?=?0.001, phi?=??0.123, 95% CI (?0.207, ?0.047). Qualitative content analysis (QCA) identified four themes: (1) aggression (exceeding what was required to achieve game objectives) characterized gaming culture and pervaded gaming platforms; (2) anonymity contributed to the culture of aggression; (3) participants often did not consider aggression cyberbullying, but rather just a part of the culture of gaming platforms; and (4) participants’ responses to aggressive behaviors. Certain behaviors on gaming platforms may not be appropriately recognized as cyberbullying. Implications for social work practice with children and youth are provided. 相似文献
359.
Michael B. Berg Linda Lin Madeleine White Jacqueline Alfonso-Barry 《Journal of American college health : J of ACH》2017,65(6):372-379
Objective: The current research aimed to understand differences in smoking-related identity among college students and to illustrate the distinct characteristics of nonidentified smokers (NIS). Participants: Students from 2 colleges in Massachusetts (N = 538; April 2016). Methods: Respondents reported by online survey whether or not they had smoked a cigarette in the past 30 days and if they self-identified as smokers. Nonsmokers (NIS) and identified smokers (IS) were then compared on their smoking attitudes and behavior. Results: NIS made up 12.5% of the sample and 64% of all tobacco users. NIS perceived themselves as less addicted and were more confident in their ability to quit smoking. They also were less likely to smoke alone, buy their own cigarettes, or have friends who smoked. Conclusions: College health officials can best motivate NIS to quit smoking by focusing on peer norms and the potential of long-term addiction. 相似文献
360.
P. González-Torre S. Lozano B. Adenso-Díaz 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2017,28(2):822-838
Hundreds of thousands of people in Europe are daily receiving food, thanks to local food banks, run basically by volunteers who collect donations and distribute them to organizations. In this paper, data from a sample of food banks working in 13 European countries are analysed using Data Envelopment Analysis (DEA), trying to learn about their profiles and find some clues about the efficiency of their operations, comparing them according to variables such as the number of volunteers and permanent staff, the tonnage of food delivered and the number of people served. Significant inefficiencies were found in the sector as a result of high performance of some food banks, thus setting a high level standard of operational efficiency. Some additional results regarding food bank sizes and performance are presented. 相似文献