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   2726篇
  免费   43篇
  国内免费   4篇
教育   1917篇
科学研究   312篇
各国文化   38篇
体育   159篇
综合类   1篇
文化理论   43篇
信息传播   303篇
  2022年   26篇
  2021年   30篇
  2020年   53篇
  2019年   91篇
  2018年   110篇
  2017年   96篇
  2016年   84篇
  2015年   59篇
  2014年   74篇
  2013年   688篇
  2012年   63篇
  2011年   72篇
  2010年   44篇
  2009年   35篇
  2008年   53篇
  2007年   36篇
  2006年   35篇
  2005年   41篇
  2004年   38篇
  2003年   37篇
  2002年   38篇
  2001年   21篇
  2000年   34篇
  1999年   28篇
  1998年   21篇
  1997年   24篇
  1996年   26篇
  1995年   21篇
  1994年   15篇
  1993年   26篇
  1992年   22篇
  1991年   26篇
  1990年   26篇
  1989年   28篇
  1988年   19篇
  1987年   28篇
  1986年   15篇
  1985年   16篇
  1984年   17篇
  1983年   16篇
  1982年   19篇
  1981年   23篇
  1980年   22篇
  1979年   21篇
  1978年   22篇
  1976年   17篇
  1974年   18篇
  1971年   16篇
  1967年   17篇
  1966年   17篇
排序方式: 共有2773条查询结果,搜索用时 0 毫秒
141.
The authors used a large sample of children (N ≈ 7,400) participating in the Early Childhood Longitudinal Study--Kindergarten Cohort (ECLS-K) to estimate kindergarten children's academic achievement growth trajectories in reading and mathematics. The authors were particularly interested in whether the growth trajectories of children with learning disabilities (LD) or speech language impairments (SLI)--as well as those of other groups of children--were consistent with a cumulative or compensatory developmental cycle. Both LD and SLI children displayed significantly lower levels of kindergarten reading achievement than nondisabled children. However, and over the subsequent 5 years of elementary school, only children with SLI lagged increasingly behind nondisabled peers in their reading skills growth. The authors observed a different pattern for mathematics achievement. Children with LD, but not SLI, lagged increasingly behind nondisabled children in their mathematics skills growth. The authors also observed some consistency in "poor-get-poorer" effects across reading and mathematic achievement for additional population subgroups. Those kindergarten children who were from lower socioeconomic status families, who were African American, and who more frequently displayed learning-related behavior problems initially had lower levels of reading and mathematics achievement and also lagged increasingly behind in their acquisition of these skills over time. Some groups of children, including those with SLI, experience a cumulative rather than a compensatory cycle of achievement growth.  相似文献   
142.
In this paper, we utilize transmission-line matrix simulations to study the electromagnetic properties of hyperbolic metamaterial grids, which are synthesized by arranging unloaded transmission lines over electrical ground planes, such that the unit cells are rectangular in shape. The hyperbolic grids support Bragg and Hyperbolic resonant modes that have rectangular and hyperbolic dispersion surfaces, respectively. We demonstrate the formation of these resonant modes in the hyperbolic grids and their refraction, and spatial scanning properties via circuit simulations. The simulation results are compared with experimental results of a two-layer anisotropic hyperbolic metamaterial.  相似文献   
143.
Repeated-sprint training often involves short sprints separated by inadequate recovery intervals. The effects of interval duration on metabolic and performance parameters are unclear. We compared the effects of two training programmes, differing in rest interval duration, on muscle (vastus lateralis) metabolism and sprint performance. Sixteen men trained three times a week for 8 weeks, each training session comprising 2-3 sets of two 80-m sprints. Sprints were separated by 10 s (n = 8) or 1 min (n = 8). Both training programmes improved performance in the 100-, 200-, and 300-m sprints, but the improvement was greater in the 10-s group during the final 100 m of the 200- and 300-m runs. Independent of interval duration, training mitigated the drop of muscle ATP after two 80-m sprints. The drop in phosphocreatine and the increases in glucose-6-phosphate and fructose-6-phosphate after two 80-m sprints were greater in the 10-s group. In conclusion, training with a limited number of repeated short sprints (≤10 s) may be more effective in improving speed maintenance in 200- and 300-m runs when performed with a 1:1 rather than a 1:6 exercise-to-rest ratio. This may be due to a greater activation of glycolysis caused, in part, by the limited resynthesis of phosphocreatine during the very short rest interval.  相似文献   
144.
International Journal of Science and Mathematics Education - This research study investigated conceptions about buoyancy held by 55 elementary preservice teachers enrolled in a science methods...  相似文献   
145.
This article looks at 360° feedback, as well as mistakes and misuses that are often made in its implementation and use. Too often individuals look for tools to give them facts to support predetermined opinions rather than gathering facts to support individuals in their growth and development process. By identifying these issues and addressing them up front, larger issues that can negatively affect the overall culture of an organization can be avoided.  相似文献   
146.
Sexuality education programs can be broadly categorized as either risk-avoidance or risk-reduction approaches. Health educators in Utah public schools must teach a state mandated risk-avoidance curriculum which prohibits the advocacy or encouragement of contraception. Multiple national surveys indicate that parents prefer a risk-reduction approach to sexuality education that promotes abstinence and the use of condoms or contraception for prevention of unwanted pregnancy and sexually transmitted infection. To date, no survey of Utah parents has been conducted.

This study utilized an Internet survey to gather data from 344 Utah parents to analyze their preferences regarding school-based sexuality education, sexuality topics, and support for objectives from the National Sexuality Education Standards. The vast majority of Utah parents surveyed support a risk-reduction approach to sexuality education, a wide variety of sexuality topics, and the majority of National Sexuality Education Standards. Statistically significant differences were identified by parents’ education, income, attendance at religious services, and political affiliation. Results support that Utah laws and education policies should be reexamined to provide for instruction that aligns with professional recommendations, best-practice recommendations based on peer-reviewed research, parental attitudes, and the needs of Utah teens.  相似文献   
147.
Schools are an important context for both basic and applied scientific research. Unlike the laboratory, however, the physical and social conditions of schools are not under the exclusive control of scientists. In this article, we liken collecting data in schools to putting on a theatrical production. We begin by describing the large cast of characters whose collaborative efforts make school‐based research possible. Next, we address the critics, including the university Institutional Review Board (IRB) and school administrators, whose feedback often improves the final study design. We then turn our attention to set building, stage directions, and rehearsals—key steps in the iterative process of refining study procedures. We end with a discussion of the day of data collection itself and activities that take place after the curtain drops. Throughout, we make recommendations based on our recent experience collecting data at several high schools.  相似文献   
148.
Gale  George 《Metascience》2019,28(2):317-319
  相似文献   
149.
150.
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