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   119105篇
  免费   1865篇
  国内免费   278篇
教育   82363篇
科学研究   13318篇
各国文化   1981篇
体育   9388篇
综合类   204篇
文化理论   1066篇
信息传播   12928篇
  2021年   964篇
  2020年   1659篇
  2019年   2564篇
  2018年   3076篇
  2017年   3357篇
  2016年   3384篇
  2015年   2329篇
  2014年   3210篇
  2013年   27304篇
  2012年   2435篇
  2011年   2801篇
  2010年   2427篇
  2009年   2690篇
  2008年   2455篇
  2007年   2185篇
  2006年   2484篇
  2005年   2449篇
  2004年   3036篇
  2003年   2350篇
  2002年   2151篇
  2001年   2077篇
  2000年   1679篇
  1999年   1568篇
  1998年   1462篇
  1997年   1414篇
  1996年   1546篇
  1995年   1353篇
  1994年   1342篇
  1993年   1339篇
  1992年   1364篇
  1991年   1271篇
  1990年   1328篇
  1989年   1189篇
  1988年   1048篇
  1987年   996篇
  1986年   1019篇
  1985年   1247篇
  1984年   1162篇
  1983年   1076篇
  1982年   1075篇
  1981年   1014篇
  1980年   958篇
  1979年   1069篇
  1978年   1049篇
  1977年   955篇
  1976年   862篇
  1975年   705篇
  1974年   699篇
  1973年   676篇
  1972年   513篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
991.
Cell-cell interactions play a key role in regeneration, differentiation, and basic tissue function taking place under physiological shear forces. However, current solutions to mimic such interactions by micro-patterning cells within microfluidic devices have low resolution, high fabrication complexity, and are limited to one or two cell types. Here, we present a microfluidic platform capable of laminar patterning of any biotin-labeled peptide using streptavidin-based surface chemistry. The design permits the generation of arbitrary cell patterns from heterogeneous mixtures in microfluidic devices. We demonstrate the robust co-patterning of α-CD24, α-ASGPR-1, and α-Tie2 antibodies for rapid isolation and co-patterning of mixtures of hepatocytes and endothelial cells. In addition to one-step isolation and patterning, our design permits step-wise patterning of multiple cell types and empty spaces to create complex cellular geometries in vitro. In conclusion, we developed a microfluidic device that permits the generation of perfusable tissue-like patterns in microfluidic devices by directly injecting complex cell mixtures such as differentiated stem cells or tissue digests with minimal sample preparation.  相似文献   
992.
993.
This study sought to assess current and future school psychologists’ attitudes toward and preparedness to address the needs of lesbian, gay, bisexual, and transgender (LGBT) students in schools. Two‐hundred seventy‐nine school psychologists (n = 162, 58%) and school psychology graduate students (n = 117, 42%) were included in the study. Participants completed measures of attitudes toward LGBT students, preparedness to address the needs of LGBT youth, and social desirability. For both school psychologists and graduate students, increased education was associated with improved attitudes and increased preparedness to treat LGBT youth. For school psychologists, presence of a gay‐straight alliance was associated with increased knowledge about LGBT youth, as well as higher ratings of preparedness to treat LGBT youth; the same associations did not hold true for the graduate students. These findings have implications for the training and practice of school psychologists in addressing the needs of LGBT youth in schools.  相似文献   
994.
995.
996.
997.
The purpose of this investigation was to examine the efficacy of a new preschool oral language and early literacy curriculum package (Teaching Early Literacy and Language [TELL]) for children with developmental speech and/or language impairment (DSLI) either as a primary (e.g., specific to speech and/or language) or secondary impairment (e.g., developmental delay that includes DSLI). Participants included 118 children (30 females, 88 males, M age = 53.58 months) with DLSI and their 29 preschool teachers. The design was a randomized controlled trial (RCT) with assignment to experimental versus contrast conditions at the classroom level. Teachers in TELL classes received formal training, in-class support, and mentoring to implement the curriculum. Dependent measures for the children included scores on the Clinical Evaluation of Language Fundamentals-Preschool 2nd edition (CELF-P2), the Phonological Awareness Literacy Screening for Preschool (PALS-PreK), the Renfrew Bus Story (BUS), and a receptive and expressive vocabulary measure developed for this investigation (VOCAB). Results indicated that when compared to the contrast group, children in the TELL condition demonstrated greater gains on the phonological awareness subtest of the CELF-P2, the sentence length score of the BUS, the letter sounds, beginning sound awareness, and rhyme awareness subtests of the PALS-PreK, and VOCAB. Results suggest that the TELL curriculum package has promise for promoting gains in early literacy and oral language skills in preschool children with DLSI.  相似文献   
998.
One of the most controversial issues in special education over the last 40 years has been the extent to which students with learning disabilities (LD) should be educated in general education classrooms. Recent mandates in federal law requiring that all students with disabilities have access to the general education curriculum and make adequate yearly progress relative to this content have intensified this debate. In this article, a brief summary of research regarding the nature of instruction that produces significantly improved educational outcomes for students with LD is provided. This is followed by a review of research related to the delivery of this high‐quality instruction in inclusive, general education classrooms and in resource settings. We conclude that this research provides the foundation for reconsidering full inclusion and how services are delivered for elementary students with LD.  相似文献   
999.
1000.
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