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   10885篇
  免费   149篇
  国内免费   122篇
教育   7057篇
科学研究   1272篇
各国文化   111篇
体育   1669篇
综合类   20篇
文化理论   75篇
信息传播   952篇
  2021年   86篇
  2020年   169篇
  2019年   223篇
  2018年   304篇
  2017年   305篇
  2016年   284篇
  2015年   203篇
  2014年   261篇
  2013年   1743篇
  2012年   234篇
  2011年   243篇
  2010年   203篇
  2009年   227篇
  2008年   208篇
  2007年   196篇
  2006年   217篇
  2005年   194篇
  2004年   396篇
  2003年   364篇
  2002年   356篇
  2001年   409篇
  2000年   248篇
  1999年   174篇
  1998年   112篇
  1997年   103篇
  1996年   108篇
  1995年   121篇
  1994年   104篇
  1993年   86篇
  1992年   160篇
  1991年   128篇
  1990年   145篇
  1989年   165篇
  1988年   128篇
  1987年   136篇
  1986年   126篇
  1985年   143篇
  1984年   130篇
  1983年   129篇
  1982年   104篇
  1981年   90篇
  1980年   103篇
  1979年   142篇
  1978年   99篇
  1977年   78篇
  1976年   98篇
  1975年   70篇
  1974年   79篇
  1973年   71篇
  1971年   68篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
971.
The Antarctic continent on the planet Earth is full of environmental extremes. It is considered as natural stress model. Therefore, the present study examined the effect of harsh environment on the certain salivary markers of 28th Indian Antarctic expeditioners. Thirty healthy men and women (median age 36 year; range 22–61 year) participated in this study. Parameters measured were salivary IgA (SIgA), IgM (SIgM), TGF-β and cortisol level at three different time points: (I) before leaving India on 26th October 2008 for base line level; (II) after 1 month on-board journey on 31st January 2009 in Southern Ocean and (III) after 1 month staying at Maitri, Antarctica on 3rd March 2009. Our observation indicated that Ship borne journey and Antarctic environment increased the SIgA levels while that of SIgM level was not altered on-board but decreased by staying for 1 month at Antarctica. No significant alteration was found in the TGF-β and cortisol level at any point of time. The present study concluded that ship borne journey and Antarctic environment may induce the SIgA level while SIgM level decreased in environmental extremes of Antarctica.  相似文献   
972.
973.
Quantifying countermovement jump (CMJ) and landing knee flexion angle is important for performance and injury risk assessment. The purpose of the study was to compare electrogoniometer (El-Gon)- and video-derived CMJ and landing knee flexion angle. Twenty-two adults performed three CMJs while knee flexion angle was simultaneously assessed using an El-Gon and video. The average systematic offset (RMSE) of the El-Gon-derived knee flexion angle throughout the entire movement was 7.03°?±?2.69°. Excellent reliability was demonstrated by the El-Gon (ICCavg?=?0.92). Countermovement knee flexion angle, maximum landing knee flexion angle and flexion angle at maximum vertical ground reaction force were 12.0°, 10.9°, and 5.7° higher, respectively, when assessed using El-Gon (p?<?0.001), compared to video. Errors between instruments are likely due to El-Gon crosstalk, misalignment and/or axis determination. The El-Gon is a cost-effective and time-efficient alternative to video analysis for the assessment of knee flexion angle if the error is accounted for and the sensor is precisely attached.  相似文献   
974.
A lack of demographic information and data related to the achievement of short-term goals during substance abuse treatment among persons who are deaf or hard of hearing dictated the need for the study. New York State maintains a database on all individuals who participate in treatment. Within this database, 1.8% of persons in treatment for substance use disorder (SUD) were also deaf or hard of hearing. As hypothesized, members of the deaf and hard of hearing sample were older, likelier to be white, and likelier to be female, relative to the SUD-only group. For both groups, alcohol, heroin, and cocaine had the highest rates of reported use. Achievement of short-term goals in the areas of alcohol use, drug use, vocational/educational goals, and overall goals indicated no differences between the deaf and hard of hearing group and the SUD-only group. Implications of these findings are discussed.  相似文献   
975.
Children at risk for early reading difficulties were identified on entry into kindergarten, and half of these children received small-group intervention two to three times a week during their kindergarten year. The other half received whatever remedial assistance was offered by their home schools. These children were again assessed at the beginning of first grade, and those who continued to have difficulties in reading received either one-to-one daily tutoring offered by project teachers from the beginning to the end of first grade or whatever remedial assistance was offered by their home schools over the same time period. All target children were periodically assessed through the end of third grade. Results suggest that either kindergarten intervention alone or kindergarten intervention combined with first-grade intervention are both useful vehicles for preventing early and long-term reading difficulties in most at-risk children.  相似文献   
976.
Empirical data on the development of interaction, communication, and language in deafblind children is very rare. To fill this gap, a case study was conducted in which the interaction between a teacher and a deafblind boy age 3 years 4 months was analyzed. Sequential analysis of their interaction confirmed some general clinical impressions about interaction with deafblind children, and provided the basis for suggestions on how the interaction pattern might be changed.  相似文献   
977.
The moulding of the future of a nation depends on the teachers and the education they provide in schools. Research evidence from the US. National Assessment of Educational Progress (NAEP) confirms this to be the case. Quantitative analysis of data indicates that measures associated with pre-service teacher preparation are by far the strongest correlates of student achievement (Darling-Hammond 2000). The research report of Wilson, Floden, and Ferrini-Mundy (2001) also suggests a strong relationship between teacher preparation and teacher effectiveness. Other research studies similarly indicate that differences in teacher quality are the most crucial for student achievement when compared with variables such as class size, streaming, or the amount of homework (Anderson & Helms 2001; Mendro 1998; Powell & Anderson 2002; Rivkin, Hanushek & Kain 2001; Saunders & Horn 1994; Strong & Tucker 2000) as possible contributory factors. In the pursuit of improved student achievement, we therefore need to examine seriously the role of teacher variables, ranging from teacher qualifications and their subject matter knowledge, to what motivates them to take up teaching as a career and as a consequence, how they teach in classrooms.  相似文献   
978.
979.
980.
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