全文获取类型
收费全文 | 1489篇 |
免费 | 36篇 |
专业分类
教育 | 967篇 |
科学研究 | 62篇 |
各国文化 | 33篇 |
体育 | 242篇 |
文化理论 | 17篇 |
信息传播 | 204篇 |
出版年
2023年 | 11篇 |
2022年 | 8篇 |
2021年 | 21篇 |
2020年 | 45篇 |
2019年 | 58篇 |
2018年 | 119篇 |
2017年 | 118篇 |
2016年 | 101篇 |
2015年 | 63篇 |
2014年 | 57篇 |
2013年 | 387篇 |
2012年 | 63篇 |
2011年 | 51篇 |
2010年 | 32篇 |
2009年 | 44篇 |
2008年 | 36篇 |
2007年 | 39篇 |
2006年 | 27篇 |
2005年 | 21篇 |
2004年 | 22篇 |
2003年 | 19篇 |
2002年 | 22篇 |
2001年 | 9篇 |
2000年 | 4篇 |
1999年 | 7篇 |
1998年 | 12篇 |
1997年 | 12篇 |
1996年 | 10篇 |
1995年 | 9篇 |
1994年 | 3篇 |
1993年 | 7篇 |
1992年 | 5篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1976年 | 8篇 |
1975年 | 6篇 |
1974年 | 6篇 |
1973年 | 3篇 |
1966年 | 2篇 |
排序方式: 共有1525条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
Women in American science 总被引:3,自引:0,他引:3
105.
Objectives: This article examines a strategic approach to developing e‐learning capability to enhance learning opportunities for the workforce of a healthcare organization. Emphasis is given to the procurement of a bespoke Managed Learning Environment (MLE). Strategic organizational issues impacting on future e‐learning developments are considered. Methods: The 2‐year implementation plan was evaluated through a two phase external research project. The first phase focused on the effectiveness of a training programme designed to build capacity for e‐learning within the Northern area and also included a virtual learning environment usability study which informed the MLE specification. The second phase evaluation is ongoing during 2005 and interim findings are presented. Results: The MLE has been piloted and on‐line learning packages have been acquired. There has been a phased take‐up of e‐learning opportunities and e‐tutor training. Some virtual Communities of Practice have been established. Key organizational issues have been identified and ongoing findings are informing strategic planning. Conclusions: The healthcare MLE is offering enhanced learning opportunities and assisting area healthcare providers in training their dispersed workforces. Blended learning strategies are most successful. The need for protected time for e‐learning is a key issue, financial savings are available. Progress has been slowed by identified organizational constraints—the MLE's benefits are widely recognized. 相似文献
106.
Rowe DA McDonald SM Mahar MT Raedeke TD 《Research quarterly for exercise and sport》2005,76(4):407-415
A multitrait-multimethod (MTMM) matrix was used to evaluate validity evidence for a digital image manipulation (DIM) body image measurement technique in young women. One hundred one young women completed the DIM procedure and the Thompson and Gray (1995) Contour Drawing Rating Scale to measure self-ideal discrepancy and size perception accuracy components of body image. Seven-day test-retest reliability was acceptable (R = .81-.95). Convergent validity for self-ideal discrepancy was higher (r = .74) than the corresponding heterotrait, monomethod coefficients (r = .46, r = .23) and heterotrait-heteromethod coefficients (r = .18, r = .12). However, the convergent validity coefficient for size perception accuracy was r = .12. The pattern of correlations in the MTMM matrix met the criteria of Campbell and Fiske (1959) for validity of these procedures to measure self-ideal discrepancy but not size perception accuracy. The DIM procedure addresses some of the criticisms associated with figure-rating scales, such as unrepresentativeness of the figures, scale coarseness, and restriction of range in responses. DIM, therefore, represents a realistic, valid alternative to figure-rating scales for measuring self-ideal discrepancy. 相似文献
107.
108.
PurposeThe aim of this study was to evaluate the efficacy of a 17-week, 3-component lifestyle intervention for enhancing health behaviors during the coronavirus disease 2019 (COVID-19) pandemic.MethodsA parallel-group (intervention and control) study was conducted amongst 79 airline pilots over a 17-week period during the COVID-19 pandemic. The intervention group (n = 38) received a personalized sleep, dietary, and physical activity (PA) program. The control group (n = 41) received no intervention. Outcome measures for sleep, fruit and vegetable intake, PA, and subjective health were measured though an online survey before and after the 17-week period. The changes in outcome measures were used to determine the efficacy of the intervention.ResultsSignificant main effects for time × group were found for International Physical Activity Questionnaire-walk (p = 0.02) and for all other outcome measures (p < 0.01). The intervention group significantly improved in sleep duration (p < 0.01; d = 1.35), Pittsburgh Sleep Quality Index score (p < 0.01; d = 1.14), moderate-to-vigorous PA (p < 0.01; d = 1.44), fruit and vegetable intake (p < 0.01; d = 2.09), Short Form 12v2 physical score (p < 0.01; d = 1.52), and Short Form 12v2 mental score (p < 0.01; d = 2.09). The control group showed significant negative change for sleep duration, Pittsburgh Sleep Quality Index score, and Short Form 12v2 mental score (p < 0.01).ConclusionResults provide preliminary evidence that a 3-component healthy sleep, eating, and PA intervention elicit improvements in health behaviors and perceived subjective health in pilots and may improve quality of life during an unprecedented global pandemic. 相似文献
109.
110.
Matthew J. Kennedy Harold D. Ladouceur Tiffany Moeller Dickson Kirui Carl A. Batt 《Biomicrofluidics》2012,6(4)
The present work describes the operation and simulation of a microfluidic laminar-flow mixer. Diffusive mixing takes place between a core solution containing lipids in ethanol and a sheath solution containing aqueous buffer, leading to self assembly of liposomes. Present device architecture hydrodynamically focuses the lipid solution into a cylindrical core positioned at the center of a microfluidic channel of 125 × 125-μm2 cross-section. Use of the device produces liposomes in the size range of 100–300 nm, with larger liposomes forming at greater ionic strength in the sheath solution and at lower lipid concentration in the core solution. Finite element simulations compute the concentration distributions of solutes at axial distances of greater than 100 channel widths. These simulations reduce computation time and enable computation at long axial distances by utilizing long hexahedral elements in the axial flow region and fine tetrahedral elements in the hydrodynamic focusing region. Present meshing technique is generally useful for simulation of long microfluidic channels and is fully implementable using comsol Multiphysics. Confocal microscopy provides experimental validation of the simulations using fluorescent solutions containing fluorescein or enhanced green fluorescent protein. 相似文献