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   19471篇
  免费   274篇
  国内免费   54篇
教育   14202篇
科学研究   1441篇
各国文化   225篇
体育   1493篇
综合类   46篇
文化理论   128篇
信息传播   2264篇
  2021年   208篇
  2020年   295篇
  2019年   447篇
  2018年   604篇
  2017年   631篇
  2016年   574篇
  2015年   379篇
  2014年   553篇
  2013年   4093篇
  2012年   522篇
  2011年   542篇
  2010年   474篇
  2009年   462篇
  2008年   485篇
  2007年   451篇
  2006年   495篇
  2005年   430篇
  2004年   315篇
  2003年   308篇
  2002年   268篇
  2001年   406篇
  2000年   332篇
  1999年   288篇
  1998年   205篇
  1997年   195篇
  1996年   200篇
  1995年   170篇
  1994年   177篇
  1993年   172篇
  1992年   240篇
  1991年   228篇
  1990年   263篇
  1989年   233篇
  1988年   196篇
  1987年   203篇
  1986年   201篇
  1985年   185篇
  1984年   192篇
  1983年   175篇
  1982年   137篇
  1981年   140篇
  1980年   137篇
  1979年   199篇
  1978年   167篇
  1977年   119篇
  1976年   129篇
  1975年   112篇
  1974年   106篇
  1973年   117篇
  1971年   113篇
排序方式: 共有10000条查询结果,搜索用时 375 毫秒
51.
Recent implementation of Nebraska's Standards-based Teacher-led Assessment and Reporting System (STARS) introduced a unique opportunity to examine the benefits and drawbacks of a teacher-led state assessment system. STARS is unique among state assessment systems in that statewide tests are replaced by locally developed assessments designed by teachers. Benefits of this system are found to be greater teacher use of results for instructional planning, greater diagnostic utility of the assessments, and gains in assessment literacy. Disadvantages include the time-consuming and stressful nature of creating localized assessments. Compatibility of STARS with the requirements of the No Child Left Behind Act are discussed.  相似文献   
52.
The aim was to examine cross-cultural variation in linguistic responsiveness to young children in 10 English-speaking mother–child dyads and 10 Italian-speaking mother– child dyads. All 20 children were late talkers who possessed delays in expressive vocabulary development but age-appropriate cognitive and receptive language skills. Dyads were filmed in 15 minute free play contexts, which were transcribed and coded for measures of maternal linguistic input (e.g. rate, MLU, labels, expansions) and child language productivity (e.g. utterances, different words used). The results revealed that the Italian mothers used more utterances, spoke more quickly and used a more diverse vocabulary than the Canadian mothers. The Italian children mirrored their mothers and also used more utterances and a more diverse vocabulary than the Canadian children. Mothers in both groups used similar percentages of responsive labels and expansions. However, Italian mothers responded to fewer of their children's vocalisations, using a smaller percentage of imitations and interpretations than the Canadian mothers. Correlations between maternal input and children's language productivity revealed that contingent language measures (e.g. imitations, interpretations, expansions) were related to high levels of productivity in children in both cultural groups. The results support the use of language interventions based on increasing maternal responsiveness for these children at the one-word stage of language development. They also point to differences that may be culturally based. For example, Italian mothers use faster rates of interaction and appear to have higher expectations for their children's verbal participation in interaction. This is reflected in higher rates of language production from their children, even though children in both cultural groups have similar vocabulary sizes.  相似文献   
53.
54.
An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.  相似文献   
55.
56.
57.
The research discussed in the present paper, set out to find how a sample of Singaporean adolescents perceived and managed different sources of stress. The sample totalled 212 pre-university students with equal numbers of boys and girls, and a mean age of 17 years 5 months. The students attended a number of junior colleges in the republic, with the sample ethnicity reflecting national proportions. Measures of stress included Behaviour Profile, Life Events, School Stress Factors, Home-School Stress Conditions and Stress Symptoms. All measures were administered as questionnaires.

The results showed that several features of Type A behaviour emerged and that school examinations, job aspirations, school work and homework were the principal stressors. Fear of the unexpected, exhaustion and lack of concentration were the most quoted stress symptoms. Science students appeared to be more stressed than arts students.

Among the main management strategies employed by these adolescents at home, were listening to music, reading and exercise, while stress in school was managed through self control, self-sufficiency and sharing problems with peers. In the main, most students seemed to be able to cope by adapting to stressful situations as they arose at a particular time.

Some of the more important implications of the above findings are discussed in the context of schooling in Singapore and in the wider context of society.  相似文献   

58.
Fielding H. Garrison's paper "The medical periodical and the scientific society" cited the Buffalo Medical Journal in the company of eminent periodicals published in Berlin, Boston, and Edinburgh. This article provides an overview of the Journal and places it in context of 19th-century medical journalism. The Journal is assessed in terms of original scientific contributions and as a source of social and local history.  相似文献   
59.
60.
This paper supplements information given in earlier papers on the UCLA MEDLARS Search Station. Four major machine problem areas in the operation of a decentralized station are identified: adjustments required to run a large information retrieval type program in an academic computing facility serving many users; handicap in running time for COBOL programs; advent of the third generation of computers with attendant preparation; and need for constant current communication among all members of a decentralized network system. Statistics are given for the initial operating period, January-May 1966: 119 search requests received, 109 formulated, and 60 fully processed. Parallel searches with other MEDLARS installations, comparisons of MEDLARS and manual Index Medicus searches, and other search activities are reported.  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