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   43277篇
  免费   907篇
  国内免费   11篇
  2019年   280篇
  2018年   3810篇
  2017年   3149篇
  2016年   2647篇
  2015年   541篇
  2014年   447篇
  2013年   1948篇
  2012年   1225篇
  2011年   3039篇
  2010年   2891篇
  2009年   1849篇
  2008年   2224篇
  2007年   2736篇
  2006年   548篇
  2005年   703篇
  2004年   632篇
  2003年   574篇
  2002年   555篇
  2001年   790篇
  2000年   778篇
  1999年   581篇
  1998年   267篇
  1997年   245篇
  1996年   252篇
  1995年   226篇
  1992年   480篇
  1991年   463篇
  1990年   456篇
  1989年   419篇
  1988年   434篇
  1987年   396篇
  1986年   402篇
  1985年   406篇
  1984年   319篇
  1983年   293篇
  1981年   230篇
  1979年   372篇
  1978年   268篇
  1977年   225篇
  1976年   219篇
  1975年   287篇
  1974年   358篇
  1973年   373篇
  1972年   289篇
  1971年   288篇
  1970年   282篇
  1969年   256篇
  1968年   351篇
  1967年   304篇
  1966年   285篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Retired and emeritus members of APGA answered a survey on their lives in retirement, their recommendations to APGA concerning activities for retired members, their suggestions for training programs in geriatric counseling, and their advice to younger counselors on planning for retirement. The results indicate most retired counselors are financially comfortable and continue to lead happy and productive lives in retirement. In their recommendations the counselors emphasized the need to remain active and stressed the importance of planning well in advance of actual retirement. They had many specific suggestions for APGA programming.  相似文献   
993.
A 32-year-old male volunteer with an eight year history of chronic unilateral tinnitus (ear-ringing) participated in a behavioral assessment strategy that included a series of measurement and modification procedures. A psychophysical matching technique was employed throughout a planned combination of procedures to assess and manipulate the intensity or loudness of tinnitus responses. Following baseline assessment, measurements were conducted at varying times of the day, concomitant with exposure to music, during progressive relaxation training, and under conditions of caffeine consumption. The value of careful assessment to describe cues and conditions associated with tinnitus and its reduction are discussed with implications for behavior treatment design and evaluation.  相似文献   
994.
995.
Heidegger's conception of death as an attitude toward life, overlooked in current literature on death and dying, offers potential for deepening our understanding of the care of non-critically ill patients. By breaking away from the notion of death as an event distinct from life and viewing it as an anticipated possibility at every moment of life, Heidegger provides insight into our attempts to evade death through our fundamental attitudes and value commitments, which in turn determine our behavior and actions. When combined with a method of application — the Nietzschean principle of reversal — these insights permit the understanding of diverse types of human mentality confronted with significant situations. Among the most important applications of these conceptions is to persons in need of medical care, and the resultant types, which are sampled as hypothetical cases, carry important implications for the sensitive care and psychosocial management of non-terminally ill patients.  相似文献   
996.
BANDAID is an intelligent computer-assisted instruction (ICAI) system designed for students learning to program in BASIC. The major thesis is that beginning students need a friendly environment, that is, one in which information about the language and the system are immediately available. The system accepts most commands without switching levels: BASIC lines are parsed on input with very specific error messages. An editor allows corrections of BASIC lines. The program can be traced while running, and an indefinite number of HELP comments can be written for the system. Without leaving the BASIC environment, the user can interact with the CMS monitor of the main machine running the program. Although no English language comments or questions are allowed, the system is modular so that additions of restrictive dialogue interaction and guided tutoring are possible. Illustrations are presented showing the capabilities of the system. The paper also presents some of the implementation details of BANDAID. A flexible system requires implementation in LISP, so examples of how the system programmer interacts with LISP during debugging are given. Although still incomplete, the system runs satisfactorily and can be used easily by beginning students and by psychologists interested in how people learn complex subjects.  相似文献   
997.
Several recent studies by Lehiste have reported that changes in fundamental frequency (F0) can serve as a cue to perceived vowel length and, furthermore, that the perceived lengthening of the vowel can influence perception of the voicing feature of stop consonants in syllable-final position. In Experiment 1, we replicated Lehiste’s basic results for stop consonants in final position. Experiment 2 extended these results to postvocalic fricatives. The final consonant in syllables of intermediate vowel duration was more often perceived as voiced when F0 was falling than when F0 was monotone. In Experiment 3, we examined the F0 contours produced by eight talkers before postvocalic stop consonants and fricatives in natural speech for minimal pairs of words differing in voicing. The amount of change of F0 over the vowel was no greater before voiced than voiceless consonants, suggesting that the earlier perceptual effects cannot be explained by appealing to regularities observed in the production of F0 contours in vowels preceding postvocalic consonants.  相似文献   
998.
It has long been known that subjects in certain inference tasks will seek evidence which can confirm their present hypotheses, even in situations where disconfirmatory evidence could be more informative. We sought to alter this tendency in a series of experiments which employed a rule discovery task, the 2-4-6 problem first described by Wason. The first experiment instructionally modified subjects confirmatory tendencies. While a disconfirmatory strategy was easily induced, it did not lead to greater efficiency in discovering the rule. The second experiment introduced subjects to the possibility of disconfirmation only after they had developed a strongly held hypothesis through the use of confirmatory evidence. This manipulation also failed to alter the efficiency of rule discovery. In the third experiment, subjects were taught to use multiple hypotheses at each step, in the manner of Platt's “Strong Inference”. This operation actually worsened performance. Finally, in the fourth experiment, the structure of the problem was altered slightly by asking subjects to seek two interrelated rules. A dramatic increase in performance resulted, perhaps because information which in previous tasks was seen as merely erroneous could now be related to an alternative rule. The four studies have broad implications for the psychological study of inference processes in general, and for the study of scientific inference in particular.  相似文献   
999.
A model of childhood hyperkinesis, using the Telomian-beagle hybrid dog, is described, demonstrating the interactions of genetics and separation in the development of this syndrome and in the favorable responses of some of these dogs to amphetamine. This work represents the collaboration of three laboratories, utilizing chiefly methods of inhibitory training. Inducing separation distress enhanced the resistance to inhibitory training and the favorable responses to amphetamine.  相似文献   
1000.
As students progress to higher and higher levels in the acquisition of a skill their number gets smaller and smaller. This article concerns the average length of time it takes the members of these successively smaller groups to complete earlier stages of skill acquisition. In the data presented, which concern Red Cross swimming, the more advanced a group is the less time its members take on the average to complete a preceding stage (sequential precession). The discussion section brings out a second relation in the same data: Namely, the further the same students advance in skill acquisition the smaller the advantage they enjoy over other students at the same level (diminishing returns).  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