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   390篇
  免费   45篇
  国内免费   87篇
  2024年   1篇
  2023年   11篇
  2022年   12篇
  2021年   11篇
  2020年   19篇
  2019年   14篇
  2018年   24篇
  2017年   16篇
  2016年   17篇
  2015年   17篇
  2014年   16篇
  2013年   37篇
  2012年   26篇
  2011年   40篇
  2010年   25篇
  2009年   27篇
  2008年   34篇
  2007年   24篇
  2006年   30篇
  2005年   27篇
  2004年   19篇
  2003年   14篇
  2002年   7篇
  2001年   7篇
  2000年   6篇
  1999年   6篇
  1998年   1篇
  1996年   2篇
  1995年   3篇
  1994年   4篇
  1993年   2篇
  1992年   3篇
  1989年   2篇
  1988年   1篇
  1987年   2篇
  1986年   2篇
  1985年   2篇
  1983年   1篇
  1982年   3篇
  1981年   2篇
  1980年   2篇
  1979年   2篇
  1976年   1篇
排序方式: 共有522条查询结果,搜索用时 31 毫秒
31.
妊娠合并结核是一种对母婴健康危害极大的妊娠期疾病。在妊娠期结核病中,多数患者无明显症状,早期症状与妊娠期某些生理反应相似,加之妊娠与结核病的相互影响,x线、CT等重要的影像学检查受限,致使本病易被误诊或误治。某些抗结核药物对母婴的不良影响,使其治疗难以实施,由于结核病本身及治疗后可能对胎儿的影响,在临床上是否终止妊娠往往难以决策。本文就妊娠合并结核诊治过程中的相关问题进行综述,以期为临床诊治决策提供帮助。  相似文献   
32.
现场中的信息缺失会影响人类对事件的记忆,这对证人证言研究是非常重要的,但以往对之却鲜有研究.本研究以大学生为被试,运用信息缺失范式,采用视频录像材料,通过2个实验探讨了间隔时间和记忆负荷对错误记忆的影响.结果表明:(1)间隔时间没有影响真实记忆和错误记忆,但信心水平却随着间隔时间的延长而变化;(2)记忆负荷高低没有影响真实记忆却影响了错误记忆,在关键信息呈现条件下,降低记忆负荷可以减少错误记忆的发生;(3)信息性质会影响人们的记忆,关键信息呈现条件下的错误记忆和真实记忆均高于关键信息缺失的条件.  相似文献   
33.
Previous studies have found that attention is automatically oriented in the direction of other people's gaze. This study directly investigated whether the perceiving gaze direction modulates the orienting of observers' attention. Gaze perception was manipulated by changing the face context (head orientation) of the gaze cue: the perceived gaze angle was increased (or decreased) when the head and gaze are congruent (or incongruent), while the local‐feature information of the eye region was preserved for all stimuli. The results showed that gaze‐cueing effects were enhanced when the perceived gaze direction was averted more toward left or right, and reduced when the perceived gaze direction was closer to direct gaze. The results suggest that gaze‐cueing effects are based on mechanisms specialized for gaze perception, and the magnitude of gaze‐cueing effects was probably a function of the perceived gaze direction.  相似文献   
34.
35.
In this study, we examine when creativity is positively or negatively related to firm performance. Building on the creation–implementation tension theorized in the literature and the attention capacity perspective, we argue that the relationship between creativity and firm performance is contingent on riskiness orientation, firm size, and realized absorptive capacity. Data were collected from 761 core knowledge employees, 148 CEOs, and 148 HR executives from 148 high‐technology firms. The results indicated that core knowledge employee creativity was negatively related to firm performance when riskiness orientation was high. The relationship was positive when realized absorptive capacity was high. Finally, the relationship was more positive in small firms than in large firms. We discuss the implications of our findings for creativity research and managerial practices.  相似文献   
36.
对信息源的正向跟随倾向对决策效果的影响*   总被引:1,自引:0,他引:1  
采用实验研究的方法,检验了二元选择情形下高准确率信息源(准确率x >50%)和低准确率信息源(准确率为1?x)对决策者预测效果的影响。尽管从逻辑上二者从准确率层面具有完全相等的信息价值,然而研究结果显示,决策者更倾向于采用正向跟随而非逆向跟随的方式处理来自信息源的信息。这导致低准确信息源的价值未能得以充分利用。学习和信息源的规范性对该信息处理倾向起到调节作用。  相似文献   
37.
We report the study of the effect of strain rate on the compressive behaviour of a Zr56Al10.9Ni4.6Cu27.8Nb0.7 bulk metallic glass. The results indicated that both the strength and plasticity of the glass increase with increasing the strain rate up to 10?5 s?1, above which the strength and plasticity start to decrease. The enhanced mechanical properties under a strain rate of 10?5 s?1 are due to the emission/propagation rate of the shear bands being consistent with the strain rate.  相似文献   
38.
Carbon nanotubes have been intensively studied owing to their great potential in nanoelectronics and nanomechanical devices. Recently, experimental results have shown that single-walled carbon nanotubes (SWCNTs) change their electronic properties when subjected to strain. In this study, the electromechanical characteristics of SWCNT networks were investigated for the application of printable strain sensors on flexible substrates. SWCNT films were formed on plastic substrates of poly(ethylene terephthalate) using a spray process. In this manner, we were able to control the transparency and obtain uniform electrical properties of the films. The films are isotropic on account of the random orientation of bundles of SWCNTs. Experimental results showed a nearly linear change in the resistance across a film when it was subjected to tensile strain, even in the inelastic range of the flexible substrate. The results demonstrate the potential use of SWCNT films for highly sensitive printable strain sensors on a macroscale.  相似文献   
39.

Lead zirconate titanate (PZT) (Pb(Zr0.52Ti0.48)O3) and barium titanate (BaTiO3) thin films have been successfully prepared using a novel sol-gel- hydrothermal (SG-HT) technique at low temperatures, which involves a combination of the conventional sol-gel process and a hydrothermal method. Highly (111)-oriented PZT thin films with a single perovskite phase and polycrystalline BaTiO thin films with well developed crystallites were obtained at a processing temperature as low as 1600C. The microstructural characteristics demonstrate that the SG-HT-derived PZT and BaTiO3 thin films with good crystallinity and surface morphology are converted from the amorphous phase to the desired perovskite phase on platinum-coated and bare silicon substrates at a low processing temperature of 100-200 C. These results suggest that the SGHT technique, which is of great significance because of its low processing temperature, will become a potential and promising process for fabricating PZT, BaTiO3 and other oxide thin films.  相似文献   
40.
贪婪是人性的重要特点之一,也是哲学、经济学等领域经常讨论的话题.本文首先梳理了贪婪的概念,并将问题聚焦在对于物质的贪婪上.然后总结了贪婪的特点,并提出贪婪的定义.接着阐述了情境因素如何影响个体对贪婪的态度,以及贪婪动机如何影响自利行为.贪婪决策是个体决定是否做出贪婪行为的心理过程,受到自我意识和情绪的影响.贪婪决策过程模型整合了控制性、自动化两类加工方式,阐释了自利倾向与道德自觉相互作用的机制.本文对以上内容逐次进行讨论,并提出了未来研究的方向.  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