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   26712篇
  免费   1005篇
  国内免费   9篇
  27726篇
  2018年   378篇
  2017年   404篇
  2016年   428篇
  2015年   300篇
  2014年   371篇
  2013年   1969篇
  2012年   670篇
  2011年   707篇
  2010年   477篇
  2009年   438篇
  2008年   681篇
  2007年   621篇
  2006年   594篇
  2005年   511篇
  2004年   506篇
  2003年   512篇
  2002年   524篇
  2001年   676篇
  2000年   697篇
  1999年   534篇
  1998年   293篇
  1997年   298篇
  1996年   292篇
  1995年   269篇
  1992年   511篇
  1991年   491篇
  1990年   468篇
  1989年   444篇
  1988年   450篇
  1987年   424篇
  1986年   462篇
  1985年   453篇
  1984年   390篇
  1983年   348篇
  1982年   269篇
  1981年   293篇
  1979年   424篇
  1978年   347篇
  1977年   297篇
  1976年   303篇
  1975年   365篇
  1974年   455篇
  1973年   483篇
  1972年   358篇
  1971年   385篇
  1970年   342篇
  1969年   374篇
  1968年   451篇
  1967年   413篇
  1966年   429篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Insight reflects the unitary nature of psychic activity in contrast to the fragmentation created in abstracting categories for the purpose of study and discussion. The unique analytic clinical dyad offers a structure in which intrapsychic fragments can be actualized and integrated. As a result, the analyst's contribution is more crucially one of exploration than of revelation. Whatever the area of examination, past or present, the link to analytic immediacy offers the opportunity to make meanings meaningful, to convert known facts to psychic truths. The analyst's clinical task requires his private self-analysis as part of the collaborative exploration of how the patient's mind works. Higher level ego functioning, including acutely active remembering, is at times transiently loosened in order for the analyst to share in the clinical work of discovery. The words the analyst uses to communicate his understanding convey only approximate manifest meanings, though they structurally reveal deeper messages of importance to the patient. These verbal approximations help stimulate self-reflection in the analysand as a step in the process of gaining insight.  相似文献   
102.
EEG correlation analyses were conducted with children with and without specific learning weaknesses. Reduced left parietal correlation was found in children with dyslectic problems, and in children with adjustment and concentration problems, reduced bioelectric correlation. The frequent evidence of brain injury criteria suggests a link with general affectations of correlation but not specifically with cerebral correlation affections. It would appear to be appropriate to employ computer-assisted EEG correlation analysis, together with frequency analysis and the examination of evoked potentials in objective neurometric diagnosis where children with learning weaknesses are involved.  相似文献   
103.
104.
105.
106.
Ratings of pre-morbid intelligence level, derived from the hospital charts of 26 chronic schizophrenics, were correlated with the post-mortem brain volume measures of cortex, white matter, central grey matter, and ventricles. Contrary to hypothesis, no significant correlations were found.  相似文献   
107.
M. W. Bunder 《Studia Logica》1988,47(2):129-143
In the early thirties, Church developed predicate calculus within a system based on lambda calculus. Rosser and Kleene developed Arithmetic within this system, but using a Godelization technique showed the system to be inconsistent.Alternative systems to that of Church have been developed, but so far more complex definitions of the natural numbers have had to be used. The present paper based on a system of illative combinatory logic developed previously by the author, does allow the use of the Church numerals. Given a new definition of equality all the Peano-type axioms of Mendelson except one can be derived. A rather weak extra axiom allows the proof of the remaining Peano axiom. Note. The illative combinatory logic used in this paper is similar to the logic employed in computer languages such as ML.The author wishes to thank Dr. Roger Hindley for proofreading this paper and for making some useful suggestions. This paper was presented at the 1986 Annual Conference of the Australasian Association of Logic in Auckland, 9–12 July, 1986.  相似文献   
108.
Perception of translational heading from optical flow   总被引:3,自引:0,他引:3  
Radial patterns of optical flow produced by observer translation could be used to perceive the direction of self-movement during locomotion, and a number of formal analyses of such patterns have recently appeared. However, there is comparatively little empirical research on the perception of heading from optical flow, and what data there are indicate surprisingly poor performance, with heading errors on the order of 5 degrees-10 degrees. We examined heading judgments during translation parallel, perpendicular, and at oblique angles to a random-dot plane, varying observer speed and dot density. Using a discrimination task, we found that heading accuracy improved by an order of magnitude, with 75%-correct thresholds of 0.66 degrees in the highest speed and density condition and 1.2 degrees generally. Performance remained high with displays of 63-10 dots, but it dropped significantly with only 2 dots; there was no consistent speed effect and no effect of angle of approach to the surface. The results are inconsistent with theories based on the local focus of outflow, local motion parallax, multiple fixations, differential motion parallax, and the local maximum of divergence. But they are consistent with Gibson's (1950) original global radial outflow hypothesis for perception of heading during translation.  相似文献   
109.
After 12-15 ejaculatory series, each consisting of several short intromissions (2- to 3-s vaginal penetration) and an ejaculation, male golden hamsters adopt an altered copulatory pattern consisting of long intromissions (5- to 25-s penetration with intravaginal thrusting). Receptivity declines and the tendency for the female to attack the male increases at about the time of this shift in copulatory pattern. Because the mean interintromission interval (III) between short intromissions is about 8 s compared to 100 s between long intromissions, it is possible that females detect this difference and adjust their mating accordingly. When the III between short intromissions from a rested male was experimentally increased to 100 s by use of a halter and lead device, the duration of lordosis was significantly less than that displayed by females paired with control males (8-s III) and virtually the same as that displayed by females paired with males that produced only long intromissions. This suggests that the female uses the temporal patterning of intravaginal stimulation as one criterion for terminating mating with a particular male.  相似文献   
110.
This study assessed how confidence in judgments is affected by the need to make inferences about missing information. Subjects indicated their likelihood of taking each of a series of gambles based on both probability and payoff information or only one of these sources of information. They also rated their confidence in each likelihood judgment. Subjects in the Explicit Inference condition were asked to explicitly estimate the values of missing information before making their responses while subjects in the Implicit Inference condition were not. The manner in which probability information was framed was also manipulated. Experiment 1 employed hypothetical gambles and Experiment 2 employed gambles with real money. Expressed likelihood of taking gambles was higher when probability was phrased in terms of '% chance of winning' rather than '% chance of losing', but this difference was somewhat less with real gambles than with hypothetical gambles. Confidence ratings in each experiment were actually higher on incomplete information trials than on complete information trials in the Explicit Inference condition. Results were related to the general issue of confidence in judgments.  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