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   63266篇
  免费   3164篇
  国内免费   500篇
管理学   1759篇
劳动科学   9篇
民族学   907篇
人才学   13篇
人口学   761篇
丛书文集   8151篇
理论方法论   2551篇
综合类   46921篇
社会学   3274篇
统计学   2584篇
  2024年   63篇
  2023年   373篇
  2022年   506篇
  2021年   662篇
  2020年   853篇
  2019年   838篇
  2018年   807篇
  2017年   1011篇
  2016年   1088篇
  2015年   1406篇
  2014年   3279篇
  2013年   4309篇
  2012年   4144篇
  2011年   4732篇
  2010年   3795篇
  2009年   3833篇
  2008年   4023篇
  2007年   4852篇
  2006年   4859篇
  2005年   4316篇
  2004年   4022篇
  2003年   3963篇
  2002年   3274篇
  2001年   2760篇
  2000年   1489篇
  1999年   471篇
  1998年   230篇
  1997年   163篇
  1996年   151篇
  1995年   107篇
  1994年   79篇
  1993年   63篇
  1992年   70篇
  1991年   43篇
  1990年   30篇
  1989年   29篇
  1988年   26篇
  1987年   12篇
  1986年   14篇
  1985年   27篇
  1984年   38篇
  1983年   27篇
  1982年   23篇
  1981年   12篇
  1980年   14篇
  1979年   18篇
  1978年   15篇
  1977年   7篇
  1976年   1篇
  1975年   3篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
近代巴蜀诗人李士棻曾被曾国藩誉为“太白醉魂”,为曾府门下“四川三李”之一,其诗作有浓郁的巴蜀文化特色。然李氏仕宦不显,长期以来学界对其关注不足,学界近年不多的相关研究,多围绕国内所存的文献,对其诗歌创作进行艺术分析,对诗人的生平介绍多简单略过,没有严谨的考证,目前仍然很有争议。通过搜罗国内外现存典籍,综合目前所见李士棻本人著述,辅以晚清近代重要报刊《申报》和与李氏有交往的朝鲜文人文献,考证其生卒年及别号,冀为今后的相关研究解决基础问题。  相似文献   
72.
公平关切影响决策行为,为分析公平关切对线上与线下销售渠道决策行为和竞争策略影响,构建线上与线下销售渠道博弈模型。基于博弈模型,对比分析四种公平关切情况对线上与线下决策变量和利润影响。进一步,为获得线上与线下稳定博弈结果,基于四种公平关切构建演化博弈模型,分析不同公平关切行为对销售渠道参与者决策行为影响。研究主要得到:一方采取公平关切时,会减少另一方收益;一方采取合作公平关切策略与另一方采取公平关切密切相关,也即当一方采取公平关切概率大于某一阀值时,另一方采取不公平关切;线上与线下经过长期演化博弈,演化稳定点为双方都采取公平关切。  相似文献   
73.
The modified Weibull distribution can be used quite effectively to model complex data from mechanical engineering or survival analysis studies that posses a monotonic or a bathtub-shape hazard rate. In this paper, we study the MLEs of the parameters of a modified Weibull distribution model in the presence of upper kth record values. The existence and uniqueness of the MLEs are proven in this case. Real data analysis is performed for illustrative purposes.  相似文献   
74.
Objective: The objective of this study was to understand substance use patterns of alcohol, marijuana, and simultaneous alcohol and marijuana (SAM) use among 2- and 4-year college students. Participants: Participants were 526 young adults aged 18–23 (n?=?355 4-year students; n?=?171 2-year students) recruited from February 2015 to January 2016 who were participating in a larger longitudinal study. Methods: Latent class analysis (LCA) was used to identify past-month classes of alcohol, marijuana, and SAM use. Results: Among both 2- and 4-year students, a four-class solution yielded the best-fitting model, with 2-year classes tending to include greater marijuana use and less alcohol use and 4-year classes tending to include heavy alcohol use. Demographic characteristics were largely similar across classes. Conclusions: Classes of alcohol, marijuana, and SAM use differed by education status. Screening and prevention efforts for 4-year students may need to be tailored for the needs of 2-year students.  相似文献   
75.
Objective: To examine differences in complete response rates for depression screening questions based on demographic characteristics. Methods: Cross-sectional study examining associations between demographic characteristics and completely responding depression-screening questions. Participants: “Healthy Minds Study” data, collected in a public University in February 2016, where 7,326 students participated. Results: women (AOR: 0.69; 95% CI =0.57–0.83) and gay/lesbian students (AOR: 0.24; 95% CI =0.10–0.60) had better complete response rates. Non-US (AOR: 1.46; 95% CI =1.03–2.07), black (AOR: 3.32; 95% CI =1.92–5.77), and Middle-Eastern students (AOR: 3.73; 95% CI =1.73–8.02) had lower complete response rates. Conclusions: Our study shows sex, gender, citizenship, and race categories have significant differences in complete response rates for the outcome. Our findings have several implications; including recognizing interventions for depression based on responders may not target those that tend to be “partial-responders”. Efforts in survey design, recruiting and completion of surveys should be maximized.  相似文献   
76.
本文研究了空气中多种醛酮的测定。目前国内仅对空气中甲醛的测定研究较多,国外报导的方法需用萃取、浓缩等一系列前处理过程,方法麻烦,易引入杂质造成污染。本文报导的方法系采用2.4—二硝基苯肼的甲醇强酸溶液吸收空气中醛酮直接注入液相色谱仪中进行分离测定。研究表明:本法分离效果好,重复性好,方法简便,速度快,测定的精密度和准确度符合微量分析误差的要求。  相似文献   
77.
The purpose of this brief is to present several case vignettes that illustrate omissions in the investigation of elder deaths. These vignettes demonstrate the need for a standardized approach in the conduct of medicolegal investigations of fatal elder abuse. For each of the described oversights, a recommendation is offered to address the gap in investigation processes, which in turn could improve the determination of cause and manner of elder death. Inherent limitations of resources and practical realities of death investigation are discussed and recommendations are made for future research. Viewed broadly, deficiencies in elder death investigations can lead to the underreporting of elder abuse and the reduction of legal options for victims, which may reflect a systemic pattern of social injustice.  相似文献   
78.
ABSTRACT

We urgently need a new global solidarity movement, but it will not be shaped like the old ones, with failing solidarity when it is most needed or at the service of anti-imperialist regimes. What we need, urgently, is a global movement for a just transition, combining social and environmental justice, as well as a strong movement against re-emerging fascism, in North and South.  相似文献   
79.
现阶段,我国步入了创新驱动引领升级的关键时期,科技创新受到了整个社会的空前重视。科技保险作为分散和转移科技风险的重要手段,可以为科技创新提供有力的风险保障。目前,我国科技保险工作已经进入全面推广阶段,虽然取得了一定的成效,但整体运行并不理想,科技企业参保率低,科技保险缺失严重。究其原因,主要在于制度供给不能适应科技企业对科技保险的需求,科技保险制度供求非均衡,在现行的科技保险制度下积聚着大量的潜在利润,而这些潜在利润既是科技保险制度非均衡的原因,又是科技保险制度创新的动力。  相似文献   
80.
Portfolio evaluation is the evaluation of multiple projects with a common purpose. While logic models have been used in many ways to support evaluation, and data visualization has been used widely to present and communicate evaluation findings, adopting logic models for portfolio evaluation and using data visualization to share findings simultaneously is surprisingly limited in the literature. With the data from a sample portfolio of 209 projects which aims to improve the system of early care and education (ECE), this study illustrated how to use logic model and data visualization techniques to conduct a portfolio evaluation by answering two evaluation questions: “To what extent are the elements of a logic model (strategies, sub-strategies, activities, outcomes, and impacts) reflected in the sample portfolio?” and “Which dominant paths through the logic model were illuminated by the data visualization technique?” For the first question, the visualization technique illuminated several dominant strategies, sub-strategies, activities, and outcomes. For the second question, our visualization techniques made it convenient to identify critical paths through the logic model. Implications for both program evaluation and program planning were discussed.  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