全文获取类型
收费全文 | 26333篇 |
免费 | 341篇 |
国内免费 | 45篇 |
专业分类
教育 | 18257篇 |
科学研究 | 3111篇 |
各国文化 | 198篇 |
体育 | 1985篇 |
综合类 | 12篇 |
文化理论 | 250篇 |
信息传播 | 2906篇 |
出版年
2021年 | 225篇 |
2020年 | 360篇 |
2019年 | 521篇 |
2018年 | 1239篇 |
2017年 | 1294篇 |
2016年 | 1053篇 |
2015年 | 479篇 |
2014年 | 599篇 |
2013年 | 3983篇 |
2012年 | 594篇 |
2011年 | 818篇 |
2010年 | 735篇 |
2009年 | 562篇 |
2008年 | 658篇 |
2007年 | 723篇 |
2006年 | 416篇 |
2005年 | 434篇 |
2004年 | 502篇 |
2003年 | 411篇 |
2002年 | 323篇 |
2001年 | 624篇 |
2000年 | 525篇 |
1999年 | 426篇 |
1998年 | 237篇 |
1997年 | 265篇 |
1996年 | 249篇 |
1995年 | 211篇 |
1994年 | 239篇 |
1993年 | 186篇 |
1992年 | 338篇 |
1991年 | 325篇 |
1990年 | 321篇 |
1989年 | 347篇 |
1988年 | 292篇 |
1987年 | 269篇 |
1986年 | 296篇 |
1985年 | 348篇 |
1984年 | 269篇 |
1983年 | 273篇 |
1982年 | 243篇 |
1981年 | 210篇 |
1980年 | 196篇 |
1979年 | 273篇 |
1978年 | 239篇 |
1977年 | 196篇 |
1976年 | 186篇 |
1975年 | 169篇 |
1974年 | 175篇 |
1973年 | 176篇 |
1971年 | 144篇 |
排序方式: 共有10000条查询结果,搜索用时 250 毫秒
1.
Jonathan S. Jones Anna-Lynne R. Adlam Abdelmalek Benattayallah Fraser N. Milton 《Child development》2022,93(3):815-830
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.
Daniel C. Kopala-Sibley Marilyn Cyr Megan C. Finsaas Jonathan Orawe Anna Huang Nim Tottenham Daniel N. Klein 《Child development》2020,91(1):110-128
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
5.
6.
7.
8.
Anthony J. Sadar 《Science & Education》2018,27(1-2):233-235
9.
Piret Luik Reelika Suviste Marina Lepp Tauno Palts Eno Tõnisson Merilin Säde Kaspar Papli 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(1):153-165
Learners who enrol in massive open online courses (MOOCs) have different backgrounds and tend to have different motivations than learners in traditional courses. Based on value-expectancy theory, an instrument was developed to measure motivation for enrolling in a programming MOOC. A study with 1229 adult participants in Estonian-language programming course “About Programming” was conducted to validate the instrument. Results of confirmatory factor analysis validated the 7-factor scale named factors influencing enrolment in MOOC (FIEM). FIEM comprises three factors of expectancies, three factors of values and one factor of social influence. The highest and lowest rated motivational factors influencing enrolment in programming MOOC are discussed in the paper. Interest in and expectations for the course, personal suitability of distance learning and suitability for family and work are the highest-rated motivational factors for those who enrol in MOOC. Usefulness related to own children, social influence and usefulness to related to certification were the lowest rated. The results of this study can be useful for designers of programming MOOCs and the developed scale might be used in future studies. 相似文献
10.
ABSTRACTThe preservation of artefacts in museum collections is profoundly affected by fluctuations in temperature and, especially, relative humidity (RH). Since the late nineteenth century, many studies have been carried out on the best way to control hygrothermal conditions. In old buildings located in maritime temperate climate zones (such as Portugal) with strong thermal inertia, and which have low ventilation rate (relative to the volume and number of visitors), daily and seasonal hygroscopic inertia may help to assure the maintenance of RH stabilization conditions. The use of expensive active systems may be minimized through the passive behaviour of internal finishing building materials. This work presents the results of an experimental laboratory study conducted in a flow chamber to demonstrate the enormous potential of hygroscopic materials in stabilizing interior relative humidity. Based in these results and in-situ monitoring in a museum housed in a building, located in Porto, with a typical construction of the 1950s (granite masonry and reinforced concrete slabs), a numerical analysis was done to quantify the influence of hygroscopic materials in stabilizing the interior relative humidity. 相似文献