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   247篇
  免费   3篇
  国内免费   1篇
教育   189篇
科学研究   12篇
各国文化   7篇
体育   19篇
文化理论   5篇
信息传播   19篇
  2022年   8篇
  2021年   5篇
  2020年   10篇
  2019年   9篇
  2018年   14篇
  2017年   10篇
  2016年   8篇
  2015年   6篇
  2014年   9篇
  2013年   50篇
  2012年   7篇
  2011年   10篇
  2010年   8篇
  2009年   2篇
  2008年   5篇
  2007年   4篇
  2006年   3篇
  2005年   3篇
  2004年   4篇
  2003年   4篇
  2002年   8篇
  2001年   2篇
  2000年   4篇
  1999年   3篇
  1998年   2篇
  1997年   4篇
  1993年   6篇
  1992年   6篇
  1991年   2篇
  1990年   3篇
  1989年   3篇
  1988年   2篇
  1987年   1篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1980年   3篇
  1977年   1篇
  1976年   1篇
  1973年   2篇
  1971年   1篇
  1970年   2篇
  1963年   1篇
  1958年   1篇
  1956年   1篇
  1921年   1篇
  1918年   1篇
排序方式: 共有251条查询结果,搜索用时 265 毫秒
161.
Beginning readers in shallow orthographies acquire word reading skills more quickly than in deep orthographies like English. In addition to extending this evidence base by comparing reading acquisition in English with the more transparent German, we conducted a longitudinal study and investigated whether different early reading skills made different contributions to word reading as a function of orthography. Children (n = 133) were recruited from the first year of primary school in New Zealand (age 5;8) and Germany (age 7;2) and from kindergartens in Germany (age 5;0) to provide both age- and schooling-matched samples. Parallel measures of phonemic awareness, vocabulary, decoding skill, and word reading (accuracy) were administered at two time points, 1 year apart. An advantage for orthography and school attendance existed for reading development. Vocabulary made a greater contribution to word reading in English than in German as did decoding skill. Findings underscore the relative importance of vocabulary and decoding skills for early reading in English.  相似文献   
162.
163.
164.
Schneider  William H. 《Minerva》2003,41(1):1-23
The Rockefeller Foundation helpedestablish two health research institutes inFrance during the German occupation and Vichyrule. These institutes were the precursors ofthe Institut National de Santé et de laRecherche Médicale (INSERM), the Frenchequivalent of the National Institutes of Healthin the United States. This essay rescues theseinstitutes from oblivion, and examines theirorigins and their significance.  相似文献   
165.
In two experiments, we investigated how learners comprehend the functioning of a three-pulley system from a presentation on a computer screen. In the first experiment (N = 62) we tested the effect of static vs. animated presentations on comprehension. In the second experiment (N = 45), we tested the effect of user-control of an animated presentation on comprehension. In both experiments the participants were university students. Comprehension was measured with a test including three comprehension indicators. The first experiment indicated that an animation as well as integrated sequential static frames enhanced comprehension. The second experiment showed that a controllable animation did not have a powerful effect on comprehension, except for learners with low spatial and mechanical reasoning abilities.  相似文献   
166.
We propose a blood separation microfluidic device suitable for point-of-care (POC) applications. By utilizing the high gas permeability of polydimethylsiloxane (PDMS) and phaseguide structures, a simple blood separation device is presented. The device consists of two main parts. A separation chamber with the phaseguide structures, where a sample inlet, a tape-sealed outlet, and a dead-end ring channel are connected, and pneumatic chambers, in which manually operating syringes are plugged. The separation chamber and pneumatic chambers are isolated by a thin PDMS wall. By manually pulling out the plunger of the syringe, a negative pressure is instantaneously generated inside the pneumatic chamber. Due to the gas diffusion from the separation chamber to the neighboring pneumatic chamber through the thin permeable PDMS wall, low pressure can be generated, and then the whole blood at the sample inlets starts to be drawn into the separation chamber and separated through the phaseguide structures. Reversely, after removing the tape at the outlet and manually pushing in the plunger of the syringe, a positive pressure will be created which will cause the air to diffuse back into the ring channel, and therefore allow the separated plasma to be recovered at the outlet on demand. In this paper, we focused on the study of the plasma separation and associated design parameters, such as the PDMS wall thickness, the air permeable overlap area between the separation and pneumatic chambers, and the geometry of the phaseguides. The device required only 2 μl of whole blood but yielding approximately 0.38 μl of separated plasma within 12 min. Without any of the requirements of sophisticated equipment or dilution techniques, we can not only separate the plasma from the whole blood for on-chip analysis but also can push out only the separated plasma to the outlet for off-chip analysis.  相似文献   
167.
168.
169.
170.
This paper consists of two major parts. First, research exploring possible interactions between metamemory and domain-specific knowledge in influencing children’s text recall and comprehension is briefly summarized. Overall, the findings indicate that metacognitive knowledge does make a difference even in cases where domain-specific knowledge is rich. Second, a recent experiment conducted in our lab and investigating the generalizability of this conclusion for sort-recall tasks is described in more detail. Third — and fourth-grade soccer experts and novices were first given a comprehensive metamemory questionnaire and then administered a sort-recall tasks using two different picture lists: whereas one list included items from various semantical categories (e.g., animals, clothes), the other list was composed of soccer pictures that could be classified in several categories such as players, kicks, or equipment. The results showed that although domain-specific knowledge had a strong impact on recall of the soccer list, general metacognitive knowledge made an independent contribution, particularly for the group of soccer experts. More specifically, good metamemory positively affected the recall of experts but had no impact on novices’ memory performance.  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