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   121975篇
  免费   1611篇
  国内免费   234篇
教育   84832篇
科学研究   13369篇
各国文化   1981篇
体育   9280篇
综合类   171篇
文化理论   1052篇
信息传播   13135篇
  2021年   927篇
  2020年   1662篇
  2019年   2559篇
  2018年   3033篇
  2017年   3320篇
  2016年   3370篇
  2015年   2303篇
  2014年   3181篇
  2013年   27272篇
  2012年   2331篇
  2011年   2660篇
  2010年   2300篇
  2009年   2611篇
  2008年   2347篇
  2007年   2066篇
  2006年   2326篇
  2005年   2304篇
  2004年   2988篇
  2003年   2317篇
  2002年   2127篇
  2001年   2001篇
  2000年   1673篇
  1999年   1529篇
  1998年   1456篇
  1997年   1515篇
  1996年   1693篇
  1995年   1466篇
  1994年   1460篇
  1993年   1469篇
  1992年   1485篇
  1991年   1391篇
  1990年   1387篇
  1989年   1313篇
  1988年   1169篇
  1987年   1104篇
  1986年   1124篇
  1985年   1398篇
  1984年   1274篇
  1983年   1274篇
  1982年   1246篇
  1981年   1169篇
  1980年   1159篇
  1979年   1216篇
  1978年   1195篇
  1977年   1106篇
  1976年   1001篇
  1975年   797篇
  1974年   799篇
  1973年   767篇
  1971年   622篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Undergraduate students who major in science make diverse career choices. Two such career choices are medical technologists and science teachers. One possible reason for science majors selecting different career choices might be attributed to varied personality dimensions. The purpose of this study was to identify a set of personality attributes that distinguish practicing medical technologists from practicing science teachers. The subjects of this study consisted of 83 medical technologists and 57 science teachers. Eysenck Personality (EPI) was utilized to investigate the personality attributes of subjects in terms of Eysenck's personality variable of Extroversion-Introversion and Neuroticism-Stability. Vocational Preference Inventory was utilized to investigate the vocational personality profile of subjects in terms of Holland's classification of occupations and work environment. Data with EPI revealed that there was no significant difference between medical technologists and science teachers with respect to Eysenck's personality variable of extroversion. However, there was found a significant difference between the two groups with respect to Eysenck's personality variable of neuroticism. Data with VPI revealed that there was no significant difference between medical technologists and science teachers with respect to Eysenck's personality variable of extroversion. Both the groups were characterized by the personality profile of IAS (Intellectual-Artistic-Social). This profile was different from that required earlier in literature.  相似文献   
992.
Over the years, professionals have hypothesized that a positive relationship exists between children's oral language proficiency and their written language performance. This study examined the following two aspects of the relationship between oral and written language: (a) Are specific linguistic components of language more closely related than others? (b) Do groups rated high, medium, or low on written language measures differ significantly in oral language proficiency? Measures of oral and written language were administered to 77 third-grade students. Results indicated that moderate relationships existed between grammatical aspects of oral and written language. Oral language proficiency was significantly different for groups rated high, medium, and low on the basis of written language performance.  相似文献   
993.
994.
995.
996.
This study aimed at investigating the relationship between intellectual, social, personal and personality variables of academically gifted secondary school students. A total of 297 tenth grade boys and girls were identified on the basis of three main criteria: 1. Academic achievement with special emphasis on Arabic language, science and math scores; 2. Behavioural traits; 3. General mental ability and general adjustment. Data related to socioeconomic status and personal characteristics were also collected. Results of the analysis of variance showed that there were significant differences between gifted and nongifted groups in general mental ability, achievement, general adjustment, behavioural traits, personal and social variables, in favour of the former.  相似文献   
997.
998.
The goal of this study was to examine the means used by textbook authors to introduce, define, and explain the mole concept in high school and introductory college chemistry textbooks. The analysis was framed by four questions:
  • 1 How is the mole defined?
  • 2 What concepts about the atom are introduced prior to the mole?
  • 3 Is Avogadro's constant presented as an experimentally determined value?
  • 4 What is the context for introducing the mole?
Twenty-nine high school and introductory college level chemistry texts were examined. After independent reading of appropriate sections of each text, discussion of differences, second or third readings of texts, and subsequent discussions, both authors reach 100% agreement concerning the results. Major conclusions were
  • 1 Two ways of defining the mole dominate the texts. One way defines the mole as Avogadro's number (6.02 × 1023) particles; the other method defines the mole in terms of carbon-12.
  • 2 All texts that present a definition in terms of C-12 introduce and define concepts about the atom prior to introducing the mole.
  • 3 Most texts at all levels point out that the value 6.02 × 1023 is an experimentally determined quantity.
  • 4 Nearly all texts discuss the mole in relation to die problem of finding a way to count particles that are too small to be directly weighed. Most texts also use a familiar counting unit, such as the dozen, to introduce the mole by analogy.
Four issues were discussed: (a) the defining attributes of the mole concept itself and the cognitive requirements for comprehending the two most frequently used definitions; (b) the connection between the definition of the mole presented in the text and the concepts about atoms that are introduced before the mole concept is developed; (c) the experimental nature of Avogadro's number; and (d) the context or setting for developing the mole concept.  相似文献   
999.
Cognitive theory suggests that a key to expert performance lies in the internal organization of the expert's knowledge. The authors contend that the type of technical illustration used during instruction influences knowledge organization and greatly impacts students' understanding of the content. This paper describes an experimental study that tested the impact of one type of conceptual illustration on students' understanding of the structure, function, and behavior of complex technical systems. The results show that supplementing traditional technical instruction with functional flow diagrams can improve overall system understanding. The functional flow diagrams were also found to be an effective instructional aid for enhancing students' conceptual understanding of the causal behavior of systems. In addition, the use of the functional flow diagram was found to significantly improve the subjects' ability to construct conceptual models that were similar to those of an expert. The implications of using conceptual diagrams for technical instruction are discussed and recommendations for future research in this area are provided.  相似文献   
1000.
While there is a clear need to address the ethical dimensions of cross-cultural counseling, the current literature lacks both a theoretical model of ethnic tolerance and a suitable measure for assessing the construct. The present study addressed this gap in the extant literature by (a) developing a measure of ethnic tolerance based upon extensive field work, (b) examining the measure's reliability and construct validity in light of two models of ethnic tolerance, and (c) examining the relationship of several factors (e.g., age, gender, and exposure to those of a different culture) to scores on the tolerance measure. Results indicated that the tolerance measure was best viewed as a unidimensional construct, had substantial content validity, and had modest construct validity. Respondents with more social contact with immigrants, as well as those who had positive experiences with immigrants, tended to score higher on the tolerance measure. Results underscore both the complexity of factors associated with tolerance and the need for counselor education programs to provide arenas for students to become aware of their own values and biases and how these may affect culturally-different clients.  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