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   34452篇
  免费   502篇
  国内免费   33篇
教育   24371篇
科学研究   3212篇
各国文化   369篇
体育   3159篇
综合类   12篇
文化理论   300篇
信息传播   3564篇
  2021年   341篇
  2020年   525篇
  2019年   749篇
  2018年   1044篇
  2017年   960篇
  2016年   969篇
  2015年   599篇
  2014年   786篇
  2013年   6255篇
  2012年   734篇
  2011年   807篇
  2010年   642篇
  2009年   622篇
  2008年   704篇
  2007年   637篇
  2006年   617篇
  2005年   544篇
  2004年   592篇
  2003年   483篇
  2002年   476篇
  2001年   840篇
  2000年   735篇
  1999年   623篇
  1998年   360篇
  1997年   385篇
  1996年   414篇
  1995年   350篇
  1994年   369篇
  1993年   312篇
  1992年   499篇
  1991年   509篇
  1990年   487篇
  1989年   514篇
  1988年   458篇
  1987年   449篇
  1986年   456篇
  1985年   530篇
  1984年   421篇
  1983年   427篇
  1982年   353篇
  1981年   339篇
  1980年   355篇
  1979年   466篇
  1978年   371篇
  1977年   334篇
  1976年   267篇
  1975年   250篇
  1974年   247篇
  1973年   249篇
  1971年   216篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
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   
102.
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   
103.
赛艇运动的项目特性及训练指导思想   总被引:13,自引:4,他引:9  
通过对赛艇运动项目决定成绩的因素,如供能系统、专项素质、生理特性的分析,确定了赛艇运动的特性及规律,并据此特性科学地提出了该项目的训练指导思想.  相似文献   
104.
对奥运会及我国大型运动会发行体育彩票融资的研究   总被引:1,自引:0,他引:1  
当代大型运动会明显表现出对资金的高需求,但是目前各国中央政府的财政收入不足是各国政府共同面临的普遍问题,这将严重影响政府对大型运动会的投入,而发行体育彩票正是解决这一问题的主要手段之一.笔者就奥运会发行体育彩票的情况和我国举办大型运动会发行体育彩票的情况及存在问题作一论述,并对我国大型运动会通过发行体育彩票的融资提出建议.  相似文献   
105.
106.
How will the expansion of the concept of construct validity affect validation practice in employment testing? How does the need for consequential validity differ in educational and employment testing? How do the research bases differ for performance assessment in these settings? Are there parallel trends in policies for test use in education and industry?  相似文献   
107.
108.
109.
This paper examines end-user, online searching using data from a questionnaire mailed to 150 Canadian health professionals in practice settings. The response rate was 83% (n = 124). The data provide a demographic profile of early adopters of end-user searching in the health care community. Positive correlations with the user's level of implementation of end-user searching were found for the following variables: amount of time spent in research activities, amount of system training received, and use of Medical Subject Headings (MeSH). There was a negative association between the amount of time spent in patient care and implementation level. General practitioners and family physicians had lower implementation levels than physicians in other specialties. Successful implementers were more likely to be computer literate and to place a high value on formal information sources such as books, journals, and libraries. Health professionals using so-called "user-friendly" or menu-based software had lower levels of personal commitment to using online databases, as measured by a combination of continuance of use, willingness to pay personally, type of recommendations made to colleagues, and hardware ownership.  相似文献   
110.
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