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   160956篇
  免费   2536篇
  国内免费   1415篇
教育   112122篇
科学研究   18171篇
各国文化   2000篇
体育   12584篇
综合类   3140篇
文化理论   1093篇
信息传播   15797篇
  2022年   957篇
  2021年   1887篇
  2020年   2428篇
  2019年   3095篇
  2018年   3416篇
  2017年   3885篇
  2016年   3855篇
  2015年   3737篇
  2014年   5400篇
  2013年   29900篇
  2012年   5577篇
  2011年   6270篇
  2010年   5747篇
  2009年   5817篇
  2008年   5709篇
  2007年   5274篇
  2006年   5295篇
  2005年   4761篇
  2004年   4690篇
  2003年   3643篇
  2002年   3420篇
  2001年   3031篇
  2000年   2285篇
  1999年   1796篇
  1998年   1508篇
  1997年   1548篇
  1996年   1710篇
  1995年   1482篇
  1994年   1471篇
  1993年   1472篇
  1992年   1519篇
  1991年   1437篇
  1990年   1439篇
  1989年   1360篇
  1988年   1233篇
  1987年   1143篇
  1986年   1177篇
  1985年   1443篇
  1984年   1310篇
  1983年   1298篇
  1982年   1249篇
  1981年   1078篇
  1980年   960篇
  1979年   1079篇
  1978年   1045篇
  1977年   960篇
  1976年   870篇
  1975年   706篇
  1974年   697篇
  1973年   675篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Working memory training improves children's cognitive performance on untrained tasks; however, little is known about the underlying neural mechanisms. This was investigated in 32 typically developing children aged 10–14 years (19 girls and 13 boys) using a randomized controlled design and multi-modal magnetic resonance imaging (Devon, UK; 2015–2016). Training improved working memory performance and increased intrinsic functional connectivity between the bilateral intraparietal sulci. Furthermore, improvements in working memory were associated with greater recruitment of the left middle frontal gyrus on a complex span task. Repeated engagement of fronto-parietal regions during training may increase their activity and functional connectivity over time, affording greater working memory performance. The plausibility of generalizable cognitive benefits from a neurobiological perspective and implications for neurodevelopmental theory are discussed.  相似文献   
2.
Early childhood is a sensitive period for learning and social skill development. The maturation of cerebral regions underlying social processing lays the foundation for later social-emotional competence. This study explored myelin changes in social brain regions and their association with changes in parent-rated social-emotional development in a cohort of 129 children (64 females, 0–36 months, 77 White). Results reveal a steep increase in myelination throughout the social brain in the first 3 years of life that is significantly associated with social-emotional development scores. These findings add knowledge to the emerging picture of social brain development by describing neural underpinnings of human social behavior. They can contribute to identifying age-/stage-appropriate early life factors in this developmental domain.  相似文献   
3.
As medical programs place increasing importance on competency-based training and surgical simulations for residents, anatomy laboratories, and body donation programs find themselves in a position of adapting to changing demands. To better assess the demand for “life-like” cadaveric specimens and evaluate the possible impacts that competency-based medical education could have upon the body donation program of McGill University, Canada, the authors tracked, over the course of the last 10 years, the number of soft-embalmed specimens, along with the number of teaching sessions and the residents enrolled in competency-based programs that are using cadaveric material. The results reveal that the number of soft-embalmed specimens used within residency training increased from 5 in 2009 to 35 in 2019, representing an increase from 6% of bodies to 36.5% of the total number of body donors embalmed in this institution. Correspondingly, the number of annual teaching sessions for residents increased from 19 in 2012 to 116 in 2019. These increases in teaching are correlated with increasing number of residents enrolled in competency-based programs over the last 3 years (Pearson r ranging from 0.9705 to 0.9903, and R2 ranging from 0.9418 to 0.9808). Those results suggest that the new skill-centered curricula which require residents to perform specific tasks within realistic settings, exhibit a growing demand for “life-like” cadaveric specimens. Institutions’ body donation programs must, therefore, adapt to those greater need for cadaveric specimens, which presents many challenges, ranging from the logistical to the ethical.  相似文献   
4.
Research in Higher Education - Given the significant need to increase and diversify graduate enrollments within computing fields, it is vital to understand what shapes students’ pathways to...  相似文献   
5.
6.
运用文献资料法、逻辑分析法等对加拿大孕期体力活动指南(2019)研制背景、方法和内容等进行分析,探究其特点和规律。主要结论:(1)孕期体力活动指南是目前该研究领域研究成果的继承和完善,重视不同类型体力活动与健康相关证据的收集,依据专家组共识、文献分析、体力活动与健康的剂量-效应关系,并通过公共意见咨询,确保指标制定过程的科学性、严谨性、适用性;(2)采用质量控制方法研制孕期体力活动指南,为受众群体提供合理化的体力活动强度、活动方式及活动安全防控等内容。建议:在“健康中国2030”目标引领下,应尽快研制我国孕期体力活动指南,为孕期体力活动提供科学依据,构建体医融合的服务模式  相似文献   
7.
Abstract

Supporting global health priorities through the development of robust health science librarianship partnerships is of significant importance. Increased demand for synthesizing evidence-based information, collating quality resources, and increasing research productivity to improve human health requires integration of library and information science skills and expertise. The Health Sciences Library (HSL) at the University of North Carolina at Chapel Hill (UNC), exists to be an indispensable partner in health information and knowledge, teaching and learning, and research. As global efforts at UNC expanded, the HSL sought to ensure that our global engagement strategy and integration were aligned with campus priorities and partner needs. The HSL created a global research partnership plan: identify resources that improve efficiency, increase access to information, build in-country capacity and expertise—all while strengthening collaborations across multiple countries. Creating a meaningful and sustainable engagement strategy was central to envisioning our path forward and can be used as a framework for consideration by librarians in similar settings.  相似文献   
8.
  • Scientific publication has been a key part of the scientific method since the inception of Philosophical Transactions in 1665.
  • The scientific publications industry has grown exponentially along with science, incorporating technological innovations along the way, and adapting journal processes and practices to changing needs of science as it matured.
  • Of all the technological innovations over more than 300 years, the move to online journals may be the most significant, making open access to content practical for the first time.
  • The open‐access movement is disrupting the economics of journal publishing, which is hoped will make the industry more competitive: the ability of the publications industry to adapt to open access will be a measure of its resilience.
  • The demand for articles published in reputable journals continues to grow as readers trust the credibility of peer reviewed journal articles, and good authors value the prestige of publishing in the best journals.
  • It is difficult to predict what new functionalities may be included in articles of the future or what additional services publishers and editors will provide, but there is every reason to believe that scientific journal articles are here to stay.
  相似文献   
9.
Seventy-nine 3-year olds and their mothers participated in a laboratory-based task to assess maternal hostility. Mothers also reported their behavioral regulation of their child. Seven years later, functional magnetic resonance imaging data were acquired while viewing emotional faces and completing a reward processing task. Maternal hostility predicted more negative amygdala connectivity during exposure to sad relative to neutral faces with frontal and parietal regions as well as more negative left ventral striatal connectivity during monetary gain relative to loss feedback with the right posterior orbital frontal cortex and right inferior frontal gyrus. In contrast, maternal regulation predicted enhanced cingulo-frontal connectivity during monetary gain relative to loss feedback. Results suggest parenting is associated with alterations in emotion and reward processing circuitry 7–8 years later.  相似文献   
10.
[目的/意义] 探索构建文献情报大数据知识资源体系,支撑面向多领域的智慧知识服务。[方法/过程] 基于AI应用需求,借鉴业界经验,梳理现有资源体系的问题,从多层次多维度扩展资源体系;构建可靠数据处理流程和计算平台,支持高效数据采集和处理;研发智能化数据治理工具,实现知识资源的有效治理,确保提供高质量数据资源。[结果/结论] 已初步形成覆盖多类型、多学科的科技文献大数据知识资源体系,构建完成高度自动化的数据采集治理流程,实施多重数据质量控制,积累数亿高质量数据,且为多个知识服务提供数据支撑。  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