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   13317篇
  免费   186篇
  国内免费   11篇
教育   9172篇
科学研究   1676篇
各国文化   114篇
体育   984篇
综合类   17篇
文化理论   160篇
信息传播   1391篇
  2022年   93篇
  2021年   138篇
  2020年   204篇
  2019年   272篇
  2018年   394篇
  2017年   416篇
  2016年   376篇
  2015年   251篇
  2014年   364篇
  2013年   2151篇
  2012年   323篇
  2011年   306篇
  2010年   297篇
  2009年   258篇
  2008年   276篇
  2007年   286篇
  2006年   269篇
  2005年   229篇
  2004年   256篇
  2003年   224篇
  2002年   235篇
  2001年   312篇
  2000年   332篇
  1999年   252篇
  1998年   138篇
  1997年   179篇
  1996年   174篇
  1995年   118篇
  1994年   130篇
  1993年   115篇
  1992年   196篇
  1991年   182篇
  1990年   213篇
  1989年   210篇
  1988年   180篇
  1987年   192篇
  1986年   172篇
  1985年   207篇
  1984年   150篇
  1983年   131篇
  1982年   124篇
  1981年   109篇
  1980年   112篇
  1979年   174篇
  1978年   130篇
  1977年   113篇
  1976年   89篇
  1975年   92篇
  1974年   94篇
  1973年   91篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
151.
Educational Studies in Mathematics - The success or failure of education systems in promoting student problem-solving skills depends on attitudinal, political, and pedagogical variables. Among...  相似文献   
152.

Amicus Curiae

A brief for individual merit in Michigan Covington &; burling for the national association of scholars  相似文献   
153.
The development of transferrable skillsets, articulated in statements of graduate learning outcomes, is emphasised in undergraduate science degree programmes. Science students enrolled in dual (double) degrees comprise a significant minority of Australian science undergraduates. Research comparing perceptions of single and dual degree students on their science learning outcomes has rarely been explored. The Science Students Skills Inventory was used to compare the perceptions of single (n = 640) and dual (n = 266) degree undergraduate science students. The instrument explored science graduate learning outcomes across six indicators: importance; the extent to which outcomes were included; the extent to which they were assessed; improvement; confidence; and likely future use. Analysis of findings, employing the plannedenactedexperienced curricula framework, offers insight into potential avenues towards coherence of the experienced curriculum by arguing the need for shared perceptions of graduate learning outcomes for single and dual degree science students. The key contribution of this study is a shift towards progressive curriculum development that draws on both single and dual degree student perspectives to achieve graduate learning outcomes. Recommendations include: whole-of-programmes curricular pathways premised on progressive development of learning outcomes that are inclusive of dual degree students, explicit interdisciplinary learning opportunities, and adoption of dual/single status as a demographic variable reported in future research.  相似文献   
154.
The aim was to study the genotoxic effect of high concentration of thyroxine (T4) in vivo in peripheral blood lymphocytes (PBL) of the patients suffering from thyroid disorders. The effect was compared by performing in vitro experiments with addition of increasing concentration of T4 (0.125–1 µM) in whole blood samples from healthy donors. Cytokinesis-blocked micronuclei (CBMN) assay method was used to assess the DNA damage in the PBL. The study included 104 patients which were grouped as control (n = 49), hyperthyroid (n = 31) and hypothyroid (n = 24). A significant increase in micronuclei (MN) frequency was observed in hyperthyroid patients when compared with the hypothyroid and euthyroid group thereby suggesting increased genotoxicity in hyperthyroidism (p < 0.001). A significant increase in MN frequency was observed at T4 concentration of 0.5 µM and above when compared to lower T4 concentrations (0.125 and 0.25 µM) and basal in in vitro experiments (p = 0.000). The results indicate that the T4 in normal concentration does not exhibit the genotoxic effect, as observed in both the in vivo and in vitro experiments. The toxicity of T4 increases at and above 0.5 μM concentration in vitro. Therefore acute T4 overdose should be handled promptly and effectively so as to avoid the possible genotoxic effect of high concentration of T4 in vivo.  相似文献   
155.
Two studies of a new science programme called WEE Science were conducted in two fifth-grade classrooms. The studies lasted for seven days in one of the classrooms and nine days in the other. At the beginning of the programme the students chose a science trade book from among the many that were selected and brought to the classroom. The students then formed groups based on the topics of the books and asked questions (Wondering) about the content. After choosing one of the 'wonderments' to pursue further, the students formed and implemented a plan for investigating (Exploring). In each classroom, each student explored, working in cooperating groups of two or more. The students then explained (Explaining) to a group of their peers what they had wondered and what and how they had explored. The students' wonderments, activities, plans, and explanations were recorded in a science notebook that had been designed for that purpose. In addition, the classrooms were videotaped while WEE Science was in progress. While the studies were successful in that most students eagerly participated in all phases of the project, some problems were encountered which created another round of wondering for the researchers. Some of these were: evaluating students' work, responding to science misconceptions of students, teaching some students to record observations in their notebooks, deciding where WEE Science would fit best in the curriculum, and anticipating its reception in the science education community.  相似文献   
156.
157.
158.
The link is equitability   总被引:1,自引:1,他引:1  
  相似文献   
159.
The relative importance of intramaze cues and extramaze cues in directing choice behavior on a radial arm maze was examined using a discrimination procedure which selectively rewarded rats for following only one set of cues. Rats in the intramaze group obtained food from a food cup on the end of each arm. Rats in the extramaze group obtained food from a food cup on a small platform just beyond the end of each arm. All rats were first shaped to perform correctly with the maze in a constant position. Then the maze was rotated to a new position after every choice. For rats in the intramaze group, the food moved with the arms, making intramaze cues relevant. For rats in the extramaze group, the food remained on the platforms (in the same position in the room), making extramaze cues relevant. Rats in the extramaze group performed almost perfectly during maze rotation, demonstrating that intramaze cues were not necessary to support accurate choice behavior. Rats in the intramaze group never performed better than chance, demonstrating that intramaze cues (from the rats, the reinforcement, and the apparatus) were not adequate to control choice behavior. The results of the present experiment are compared to those of other experiments describing the influence of “odor trails” or other olfactory stimuli on choice behavior in mazes.  相似文献   
160.
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