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   694篇
  免费   10篇
教育   396篇
科学研究   62篇
各国文化   7篇
体育   169篇
综合类   2篇
文化理论   12篇
信息传播   56篇
  2023年   4篇
  2022年   18篇
  2021年   20篇
  2020年   24篇
  2019年   42篇
  2018年   56篇
  2017年   48篇
  2016年   53篇
  2015年   26篇
  2014年   46篇
  2013年   94篇
  2012年   36篇
  2011年   31篇
  2010年   21篇
  2009年   16篇
  2008年   11篇
  2007年   11篇
  2006年   8篇
  2005年   12篇
  2004年   9篇
  2003年   15篇
  2002年   17篇
  2001年   13篇
  2000年   17篇
  1999年   3篇
  1998年   11篇
  1997年   2篇
  1996年   2篇
  1995年   5篇
  1994年   2篇
  1993年   1篇
  1992年   3篇
  1991年   2篇
  1990年   2篇
  1989年   1篇
  1988年   2篇
  1987年   1篇
  1986年   1篇
  1985年   1篇
  1984年   3篇
  1983年   2篇
  1982年   2篇
  1981年   1篇
  1980年   1篇
  1978年   1篇
  1977年   2篇
  1975年   1篇
  1974年   1篇
  1973年   1篇
  1968年   1篇
排序方式: 共有704条查询结果,搜索用时 15 毫秒
191.
Although the environmental light/dark cycle is the main zeitgeber for the human species, the social cues seem to be important in the synchronization of circadian rhythms. In Brazil, the existence of two school schedules—one with only morning classes (MG) and other with only afternoon classes (AG)—allows the investigation of the effect of school activities on light exposure and sleep/wake patterns in children. Forty‐seven children wore wrist actimeters for a week for registration of light and sleep data. MG children presented shorter sleep duration on school days than the children from the AG. The results showed that during school days MG children were exposed to bright light earlier in the morning when compared to AG children. Nevertheless, there were no differences in light exposure after sunset. The results reflect the role of school schedules and artificial light in shaping light exposure, and its association with sleep timing in children.  相似文献   
192.
In outdoor activities, it seems reasonable that the longer children spend in spontaneous physical activity (PA), the higher the probability of being active. Indeed, the time spent outdoor has been identified as a variable consistently associated with the children’s PA. Outdoor playing, such as the organized sports practice, appears associated with healthier lifestyle standards. All the recommendations mention the importance of increasing daily PA practice in children and teenagers, but few studies highlight the relationship between outdoor play and the recommended PA levels. The purpose of this study is to investigate the relationships between the frequency of outdoor play, the frequency of the organized sports practice, and the compliance of the recommendations for PA practice in children in the inner city area of Porto. The sample of this study is composed of 422 individuals (mean age of 11.6 years). Two hundred and twenty-five of them were girls and 197 were boys from the sixth grade (elementary schools located in the inner city area of Porto). PA was objectively evaluated using accelerometers. Participants reported frequency of participation in different PA contexts, such as sports practice and outdoor play. The results show a predictor effect of participating in sports three or more times per week on compliance of PA guidelines.

In conclusion, organized sports practice seems more effective than outdoor play to reach the recommended levels of PA in children.  相似文献   
193.
Variability analysis has been used to understand how competitive constraints shape different behaviours in team sports. In this study, we analysed and compared variability of tactical performance indices in players within complex I at two different competitive levels in volleyball. We also examined whether variability was influenced by set type and period. Eight matches from the 2012 Olympics competition and from the Portuguese national league in the 2014–2015 season were analysed (1496 rallies). Variability of setting conditions, attack zone, attack tempo and block opposition was assessed using Shannon entropy measures. Magnitude-based inferences were used to analyse the practical significance of compared values of selected variables. Results showed differences between elite and national teams for all variables, which were co-adapted to the competitive constraints of set type and set periods. Elite teams exploited system stability in setting conditions and block opposition, but greater unpredictability in zone and tempo of attack. These findings suggest that uncertainty in attacking actions was a key factor that could only be achieved with greater performance stability in other game actions. Data suggested how coaches could help setters develop the capacity to play at faster tempos, diversifying attack zones, especially at critical moments in competition.  相似文献   
194.
VOSviewer (version 1.6.17, July 22, 2021). Centre for Science and Technology Studies, Leiden University, The Netherlands. https://www.vosviewer.com; free, donations accepted.Bibliometrix (version 3.1, Sep 24, 2021). Department of Economics and Statistics, University of Naples Federico II, Italy. ;gro.xirtemoilbib@ofni https://www.bibliometrix.org/; free, donations accepted.  相似文献   
195.
196.
对电子商务实验的开设问题提出以课程需要、应用需要以及以基本技能训练和学生创造性能力培养两方面切入实验内容的安排 ,并提供了一个实验安排的样本  相似文献   
197.
腐败的表现是多方面的。主要表现在经济活动、组织人事、执纪执法、生活作风、结交朋友、亲属管理等方面。产生腐败的原因是复杂的 ,主要有攀比心理、侥幸心理、从众心理、拜金心理。我们应采取加强教育、依靠法制、搞好监督等措施 ,将反腐败斗争进行到底。  相似文献   
198.
The objective of this study is to analyze secondary school students' interactions (conflicts, controversies, and arguments) as they participate in an intact classroom activity designed to facilitate their understanding of heat energy and temperature. The study is based on 32 ninth-grade students in a public school in Londrina, Brazil. Results obtained show that the differentiation between heat energy and temperature constitutes considerable difficulties for the students, and can be considered as part of the hard-core of their understanding (Lakatos, 1970, Criticism and the Growth of Knowledge, Cambridge University Press, Cambridge, UK, pp. 91–196). Student interactions (video taped) were classified into an Alternative Model, Transitional Model, and Scientific Model, depending on the degree to which they reflected a progressive transition in their hard-core. Students generally resisted a change in their conceptual understanding. Some students were able to question the hard-core of their beliefs and construct a Transitory Model. Some students experienced a further progressive transition by constructing a Scientific Model, based on the understanding that Temperature only measures the energy of agitation. Methodology used also provided a glimpse of how a particular student grappled with the conflicts in order to facilitate progressive transition in understanding. It is concluded that given the opportunity to discuss, reflect, consider alternative/conflicting situations, students can construct models that increase progressively in their heuristic/explanatory power.  相似文献   
199.
INTRODUCTIONAntisenseoligodeoxynucleotides (ASODN )caninhibittranscriptionandinterferewithspe cialgeneexpression .AfixedpointontheK rasgenewithhighmutationrateinpancreaticcarci nomaoffersanintracellulartargetforpancreaticcarcinomagenetherapywithASODN (Cai…  相似文献   
200.
The present article focuses on the counter stories of two Chilean social studies high school teachers. Counter stories describe how teachers use their professional experience to confront those mega narratives composed of dominant educational policies that impinge upon their pedagogical practices. The mega narrative described in this study as a citizenship education mega policy narrative is composed by citizenship educational guidelines that have become influenced by other market-driven educational policies, and is not only present in Chile but has also been influenced by policies coming from countries such as England and the US. Therefore, the discussions that emerge from these counter stories on the nature of this mega narrative and the ways through which teachers can confront it through their teaching, and the implications that all this has for the field of citizenship education, do not only fill a gap in Chilean research but also contribute to discussions on counter and mega narratives in the field of citizenship education within a wider international scope.  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