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   1488篇
  免费   24篇
  国内免费   2篇
教育   1114篇
科学研究   106篇
各国文化   23篇
体育   96篇
综合类   1篇
文化理论   13篇
信息传播   161篇
  2022年   11篇
  2021年   17篇
  2020年   23篇
  2019年   38篇
  2018年   59篇
  2017年   52篇
  2016年   58篇
  2015年   24篇
  2014年   35篇
  2013年   311篇
  2012年   32篇
  2011年   47篇
  2010年   35篇
  2009年   26篇
  2008年   34篇
  2007年   33篇
  2006年   35篇
  2005年   19篇
  2004年   36篇
  2003年   23篇
  2002年   20篇
  2001年   15篇
  2000年   29篇
  1999年   22篇
  1998年   16篇
  1997年   25篇
  1996年   27篇
  1995年   27篇
  1994年   28篇
  1993年   15篇
  1992年   21篇
  1991年   21篇
  1990年   17篇
  1989年   14篇
  1988年   10篇
  1987年   9篇
  1986年   9篇
  1985年   16篇
  1984年   17篇
  1983年   16篇
  1982年   12篇
  1981年   20篇
  1980年   11篇
  1979年   8篇
  1978年   12篇
  1976年   11篇
  1975年   8篇
  1969年   6篇
  1927年   6篇
  1923年   6篇
排序方式: 共有1514条查询结果,搜索用时 140 毫秒
81.
82.
83.
84.
85.
86.
Biomimetic scaffolds approaching physiological scale, whose size and large cellular load far exceed the limits of diffusion, require incorporation of a fluidic means to achieve adequate nutrient/metabolite exchange. This need has driven the extension of microfluidic technologies into the area of biomaterials. While construction of perfusable scaffolds is essentially a problem of microfluidic device fabrication, functional implementation of free-standing, thick-tissue constructs depends upon successful integration of external pumping mechanisms through optimized connective assemblies. However, a critical analysis to identify optimal materials/assembly components for hydrogel substrates has received little focus to date. This investigation addresses this issue directly by evaluating the efficacy of a range of adhesive and mechanical fluidic connection methods to gelatin hydrogel constructs based upon both mechanical property analysis and cell compatibility. Results identify a novel bioadhesive, comprised of two enzymatically modified gelatin compounds, for connecting tubing to hydrogel constructs that is both structurally robust and non-cytotoxic. Furthermore, outcomes from this study provide clear evidence that fluidic interconnect success varies with substrate composition (specifically hydrogel versus polydimethylsiloxane), highlighting not only the importance of selecting the appropriately tailored components for fluidic hydrogel systems but also that of encouraging ongoing, targeted exploration of this issue. The optimization of such interconnect systems will ultimately promote exciting scientific and therapeutic developments provided by microfluidic, cell-laden scaffolds.  相似文献   
87.
Libraries must continually adapt to meet the ever-changing needs of users. Doing so requires the ability to be flexible and respond quickly. This is a case study of how The George Washington University Libraries rethought its approach to collection development using a cross-functional, team-based strategy that leveraged the benefits of Agile project management. Adopting an Agile approach to collection development maximized the impact of the library’s financial resources and enabled staff to develop new skills. This project underscores the value of collaboration, agility, and experimentation in libraries.  相似文献   
88.
Infants become sensitive to emotion expressions early in the 1st year and such sensitivity is likely crucial for social development and adaptation. Social interactions with primary caregivers may play a key role in the development of this complex ability. This study aimed to investigate how variations in parenting behavior affect infants' neural responses to emotional faces. Event‐related potentials (ERPs) to emotional faces were recorded from 40 healthy 7‐month‐old infants (24 males). Parental behavior was assessed and coded using the Emotional Availability Scales during free‐play interaction. Sensitive parenting was associated with increased amplitudes to positive facial expressions on the face‐sensitive ERP component, the negative central. Findings are discussed in relation to the interactive mechanisms influencing how infants neurally encode positive emotions.  相似文献   
89.
90.
As elite youth sport becomes more organized and professionalized, the role of the family is increasingly acknowledged as being significant in the development of young talent. High-profile examples across a range of professional sports, both positive and negative, have drawn attention toward this important stakeholder. Accordingly, this review first examines the key issues in relation to family involvement in talent development in relation to what is perceived as good and bad practice on behalf of the family. Next the key theoretical underpinning is considered, Family Systems Theory, and how it may be integrated within elite youth sport. Finally, the article concludes with a summary of where the current literature leaves us and where we can progress from here. Two possible inputs are suggested that could benefit the effectiveness of family involvement: a focus on the family holistically and a second on the role different family members can play.  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