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   26878篇
  免费   449篇
  国内免费   397篇
  2023年   63篇
  2022年   77篇
  2021年   130篇
  2020年   194篇
  2019年   189篇
  2018年   3707篇
  2017年   3012篇
  2016年   2479篇
  2015年   371篇
  2014年   263篇
  2013年   679篇
  2012年   857篇
  2011年   2774篇
  2010年   2778篇
  2009年   1767篇
  2008年   2103篇
  2007年   2600篇
  2006年   406篇
  2005年   525篇
  2004年   417篇
  2003年   317篇
  2002年   220篇
  2001年   192篇
  2000年   232篇
  1999年   144篇
  1998年   90篇
  1997年   79篇
  1996年   74篇
  1995年   41篇
  1994年   41篇
  1993年   42篇
  1992年   57篇
  1991年   66篇
  1990年   63篇
  1989年   54篇
  1988年   51篇
  1987年   35篇
  1986年   24篇
  1985年   36篇
  1984年   42篇
  1983年   36篇
  1982年   29篇
  1981年   26篇
  1980年   27篇
  1979年   29篇
  1976年   25篇
  1975年   19篇
  1974年   20篇
  1973年   21篇
  1971年   27篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
161.
162.
本文研究了正常猕猴脑电图特征,将16只动物按其年龄分为哺乳期、未成年期和成年期3组。并对其中12只动物进一步观察氯丙嗪对脑电图的影响,其主要结果如下: 猕猴脑电图自发电位频率随年龄的增长而增加;振幅随年龄的增长而降低。对光刺激所呈现的“节律同化”现象,在未成年期最明显,成年期次之。 氯丙嗪能引起猕猴不同程度的脑电图变化,主要表现为全皮层高振幅慢波。氯丙嗪能改善对光脉冲刺激所呈现的“节律同化”现象。  相似文献   
163.
The concept “impossible figure” is analyzed by formalizing the interpretations of a polyhedral figure by an observer, and defining several types of inconsistency in such interpretations. Tests for these inconsistencies are developed using simple graph theory, and a sufficient condition is established for the feasibility of an interpretation. Finally, techniques are derived for the automatic construction of usual or unusual multibar figures.  相似文献   
164.
A number of experimental studies have consistently shown the locus of spatial S-R compatibility effects to be the selection of the response within an abstract memory code. The purpose of the present study was to test, in the particular case of wheel rotations, the general proposition that any response that a subject internally codes in terms of left and right may be interfered with by the lateral location of the stimuli in a Simon paradigm. Experiment 1 showed that the auditory Simon effect occurred in a task where the subjects had to rotate a steering wheel bimanually either clockwise or counterclockwise according to sound pitch, despite the fact that responses of this kind are undefined with respect to laterality. Experiment 2 confirmed this result in a unimanual rotation condition and suggested that the ear-rotation compatibility effect may be added to the effect of a biomechanical factor, pronation versus supination, supporting the idea of an abstraction motor code. In Experiment 3, subjects rotated the steering wheel with their hands on the lowest part of the wheel. When the response movement made the spot of a C.R.T. move laterally in accordance with the performed rotation, the subjects coded their response directly in terms of its effect on the visual display. For subjects not receiving visual feedback, no compatibility effect occurred. however, the individual data were compatible with the notion that some subjects in this group coded their responses in terms of wheel rotations, and others in terms of hand movements.  相似文献   
165.
In a transfer-of-control experiment with rats, Pavlovian CSs were tested for the specificity of their effects. The instrumental behavior consisted of a discriminative, conditional two-lever choice task in which qualitatively different appetitive reinforcers were contingent upon the two correct choices. In a Pavlovian phase, subjects experienced conditioning to establish either a CS+ or CS? for one reinforcer or a CS+ or CS? for the other reinforcer. Finally, in a test, these CSs were presented when there was the opportunity to make choice responses. The CS+s evoked choices of the lever which had eventuated in the reinforcer that had served as the Pavlovian US, while the CS?s showed only a slight tendency to evoke the other choice responses. When the CSs were compounded with the original SDs, the CS+s had little effect upon the vigor of responding while the CS?s reduced the vigor of responding to the SD for the reinforcer that was the same as the US used in establishing the CS?. The results are discussed in terms of associative mediational theory and the reinforcer specificity of Pavlovian conditioned excitation and inhibition.  相似文献   
166.
Effects of the dimensionality of responsibility and causality attributions were investigated. An accident was described. Subjects cued to respond with causality attributions increased their attributions with event severity. Subjects cued to respond with moral responsibility attributions decreased attributional levels with increasing severity. Assignments of guilt varied specifically with the cued attributional concept.  相似文献   
167.
方格  刘范 《心理学报》1983,16(1):61-71
本研究的目的是继续探讨不同年龄儿童对运动速度认知发展的水平和特点。被试为5—11岁儿童共205人,每组28—30人。采用个别实验。主试改用仪器显示在三种不同条件下的两个光点的等速匀速运动。令儿童比较它们的运动速度。每做完一个项目后不管儿童回答是否正确都要求他们说明理由。 实验结果表明:1)本实验条件下儿童对光点运动速度的认知同对玩具小汽车速度的认知有大体相同的发展趋势和年龄阶段的特点。2)本实验中儿童对光点速度的认知在以下几方面有别于对玩具小汽车运动速度的认知:a.从8岁起儿童依据两个光点之间的距离判断速度的人次随年龄增加。b.当儿童不能整合时、空因素时,空间因素的优势作用有减弱的趋势。3)较大儿童能采取各种策略主动解决问题。  相似文献   
168.
5—13岁儿童空间认知发展的研究——判别相等面积的再探   总被引:2,自引:0,他引:2  
李文馥  刘范 《心理学报》1983,16(1):90-99
本实验是《5—11岁儿童两种空间关系认知发展的实验研究》的继续,但将内部被占面积改为圆形。结果表明:儿童判别面积从直觉判断发展到推理判断之间经历一种过渡形态。表现为,在同一判别中直觉和推理活动交错;能将被占面积各部分整合成整体,但对剩余面积部分的判别受直觉因素束缚;理解等量减等量所余相等原理,但不能用来解决面临的课题等四种形式。完成这种过渡需要解决三个相互联系的问题。也再次证明儿童判别面积这种空间认知发展,在一定年龄范围存在着阶段性特点,同时儿童这种认知能力的显露程度又以课题条件难易为转移。  相似文献   
169.
刘范  赵淑文 《心理学报》1983,16(2):30-35
本文探讨了8—15岁儿童掌握交集概念的发展水平及解答交集应用题的过程,分析了儿童认知过程中各认知成分的交互作用。 实验结果表明:小学儿童已具有掌握简单交集概念的心理基础;对交集的认知包括概念、表象、感知操作等成分的交互作用,其中表象、感知操作成分具有重要意义;儿童解交集课题是一种主动积极的认知活动,他们主动思考,采取策略,通过实物和图片的帮助而上升到概念水平上的理解。  相似文献   
170.
Rats were either exposed or not exposed to a mouse in their living cage for a 48-hr period. At the end of this time a bilateral lesion was made in the medial accumbens region or in the medial hypothalamus. When tested 2 days postoperatively, the killing frequency among rats that had been exposed to mice preoperatively was not significantly lower than that of rats that were not preoperatively exposed. The ineffectiveness of preoperative experience in suppressing the mouse killing induced by medial accumbens and medial hypothalamic lesions is similar to that found previously with dorsal-median raphe lesions and olfactory bulb lesions and is in contrast to the ease with which preoperative experience prevents mouse killing induced by septal lesions and serotonergic lesions induced by 5,7-dihydroxytryptamine.  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