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   1171篇
  免费   43篇
  国内免费   1篇
教育   937篇
科学研究   54篇
各国文化   13篇
体育   50篇
文化理论   6篇
信息传播   155篇
  2023年   10篇
  2022年   15篇
  2021年   31篇
  2020年   29篇
  2019年   55篇
  2018年   55篇
  2017年   68篇
  2016年   73篇
  2015年   50篇
  2014年   63篇
  2013年   256篇
  2012年   43篇
  2011年   54篇
  2010年   36篇
  2009年   39篇
  2008年   37篇
  2007年   46篇
  2006年   30篇
  2005年   27篇
  2004年   28篇
  2003年   26篇
  2002年   13篇
  2001年   15篇
  2000年   11篇
  1999年   8篇
  1998年   4篇
  1997年   3篇
  1996年   7篇
  1995年   4篇
  1994年   3篇
  1993年   3篇
  1992年   6篇
  1990年   3篇
  1988年   2篇
  1987年   3篇
  1986年   5篇
  1985年   8篇
  1984年   5篇
  1983年   5篇
  1982年   3篇
  1981年   3篇
  1980年   3篇
  1979年   4篇
  1977年   3篇
  1974年   3篇
  1973年   2篇
  1972年   2篇
  1892年   1篇
  1890年   1篇
  1857年   3篇
排序方式: 共有1215条查询结果,搜索用时 93 毫秒
91.
Over the past decade, repeated calls have been made to incorporate more active teaching and learning in undergraduate biology courses. The emphasis on inquiry-based teaching is especially important in laboratory courses, as these are the courses in which students are applying the process of science. To determine the current state of research on inquiry-based teaching in undergraduate biology laboratory courses, we reviewed the recent published literature on inquiry-based exercises. The majority of studies in our data set were in the subdisciplines of biochemistry, cell biology, developmental biology, genetics, and molecular biology. In addition, most exercises were guided inquiry, rather than open ended or research based. Almost 75% of the studies included assessment data, with two-thirds of these studies including multiple types of assessment data. However, few exercises were assessed in multiple courses or at multiple institutions. Furthermore, assessments were rarely based on published instruments. Although the results of the studies in our data set show a positive effect of inquiry-based teaching in biology laboratory courses on student learning gains, research that uses the same instrument across a range of courses and institutions is needed to determine whether these results can be generalized.  相似文献   
92.
93.
Experimental analysis of social stimuli has typically been restricted to the presence or absence of verbal attention. In the present study, an ABAB design was used to assess the influence of proximity as a social stimulus. Close and distant proximity of a familiar adult was systematically manipulated to evaluate the effect of proximity on the on‐task behavior of a 15‐year‐old male with autism. Baseline, experimental analysis, and intervention phases were conducted within a self‐contained classroom. Pronounced effects of distant educator proximity to the participant were evident during both the experimental analysis and intervention, with increased on‐task behavior occurring in the distant condition. Future recommendations for the investigation of proximity as a relevant social stimulus are forwarded. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 189–196, 2005.  相似文献   
94.
95.
96.
97.
98.
Foreign firms patent in emerging economies with weak appropriability regimes at an increasing rate. This phenomenon constitutes a paradox since in such a setting foreign firms should have weak incentives to patent. In an attempt to resolve this paradox, we conducted an inductive analysis of 11 foreign firms that patent in such a setting, using the case of China as our empirical context. We identify four archetypes of foreign firms and three key antecedents the interaction of which determines which archetype a firm can be subsumed under.Our study complements the developed-economy focus of the extant appropriation literature by adding an international perspective. We extend previous econometric studies by identifying salient factors on the firm level that determine the extent to which a foreign firm patents in emerging economies with a weak appropriability regime, highlighting that the extent of a firm's motivation to maintain its freedom to operate can supersede imitability concerns. We also comment on the practical implications of these contributions for managers of foreign firms. Highlighting a structural conflict of interest between foreign firms from developed economies and the development goals of an emerging economy, we point to the generalizability of our results to a wide range of other emerging economies worldwide.  相似文献   
99.

Purpose

The purpose of the present review was to use existing, published data to provide an estimate of the amount of change in six-minute walk test distance (Δ6MWT) that represents a clinically meaningful change in individuals with chronic heart failure (CHF).

Methods

The present review included two separate literature searches of the CINAHL and Medline databases for articles that: (1) reported the intraclass correlation coefficient (ICC) of the 6MWT in individuals with CHF, and (2) used the 6MWT along with either aerobic capacity or health-related quality of life (HRQL) as study endpoints in randomized controlled trials (RCTs) of exercise-based intervention for individuals with CHF. The ICCs were used to calculate the minimum detectable difference (MDD) at the 95% confidence interval for each included study. The Δ6MWT associated with aerobic capacity and HRQL within-group effect sizes for the intervention and control groups in each included RCT was analyzed using receiver operating characteristic (ROC) curves.

Results

Thirteen articles reported the ICC for the 6MWT. The mean (standard deviation) MDD calculated based on these data was 43.1(16.8) m. Eighteen RCTs measured the 6MWT and either aerobic capacity and/or HRQL. A Δ6MWT of 40–45 m was associated with at least moderate aerobic capacity and HRQL effect sizes in the intervention groups. The Δ6MWT thresholds that discriminated between intervention and control groups using ROC curves revealed the following sensitivity/specificity for the respective thresholds: 19 m, 94.4/83.3%, 32 m, 83.3/94.4%, and 48 m 44.4/100% (AUC = .935, p = .009, CI95% .855, 1.015).

Conclusions

A Δ6MWT of approximately 45 m appears to exceed measurement error and be associated with significant changes in either aerobic capacity and/or HRQL.Key Words: heart failure, six-minute walk test, clinically meaningful change, minimum detectable difference  相似文献   
100.
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