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   14008篇
  免费   1028篇
  国内免费   427篇
  2023年   179篇
  2022年   129篇
  2021年   200篇
  2020年   421篇
  2019年   448篇
  2018年   435篇
  2017年   466篇
  2016年   403篇
  2015年   292篇
  2014年   347篇
  2013年   1122篇
  2012年   237篇
  2011年   321篇
  2010年   281篇
  2009年   386篇
  2008年   432篇
  2007年   462篇
  2006年   467篇
  2005年   393篇
  2004年   332篇
  2003年   270篇
  2002年   220篇
  2001年   162篇
  2000年   129篇
  1999年   152篇
  1998年   109篇
  1997年   81篇
  1996年   80篇
  1995年   74篇
  1994年   53篇
  1993年   54篇
  1992年   58篇
  1991年   29篇
  1990年   35篇
  1989年   41篇
  1988年   30篇
  1987年   31篇
  1985年   465篇
  1984年   596篇
  1983年   510篇
  1982年   576篇
  1981年   548篇
  1980年   541篇
  1979年   486篇
  1978年   540篇
  1977年   432篇
  1976年   408篇
  1975年   334篇
  1974年   341篇
  1973年   288篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Shu-hsien Liu 《Zygon》1989,24(4):457-468
Abstract. The traditional Chinese idea of t'ien-jen-ho-i (Heaven and humanity in union) implies that humanity has to live in harmony with nature. As science and technology progress, however, the idea appears increasingly outmoded, and it becomes fashionable to talk about overcoming nature. Ironically, though, the further science reaches the more clearly are its limitations exposed. The exploitation of nature not only endangers many life forms on earth but threatens the very existence of the human species. I propose that a reconstruction of the traditional Chinese idea of T'ien-jen-ho-i will help us envisage a new and salutary relation between humanity and nature.  相似文献   
22.
Karl E. Peters 《Zygon》1989,24(4):469-485
Abstract. Developing a scientifically grounded philosophy of cosmic evolution, and using the moral norm of completeness as dynamic harmony, this paper argues that humans are a part of nature in both its conserving and emergent aspects. Humans are both material and cultural, instinctual-emotional and rational, creatures and creators, and carriers of stability and change. To ignore any of the multifaceted aspects of humanity in relation to the rest of nature is to commit one of a number of fallacies that are grounded in a dualistic-conquest mentality. Examples of some new developments in philosophy and theology, metaphorical images, and ritual show how to overcome dualism in favor of a dynamic harmony of humanity within nature.  相似文献   
23.
24.
Two cebus monkeys, with many years of experience matching a variety of static visual stimuli (forms and colors) within a standard matching-to-sample paradigm, were trained to press a left lever when a pair of displayed static stimuli were the same and to press a right lever when they were different. After learning the same/different task, the monkeys were tested for transfer to dynamic visual stimuli (flashing versus steady green disks), with which they had no previous experience. Both failed to transfer to the dynamic stimuli. A third monkey, also with massive past experience matching static visual stimuli, was tested for transfer to the dynamic stimuli within our standard matching paradigm, and it, too, failed. All 3 subjects were unable to reach a moderate acquisition criterion despite as many as 52 sessions of training with the dynamic stimuli. These results provide further evidence that, in monkeys, the matching (or identity) concept has a very limited reach; they consequently do not support the view held by some theorists that an abstract matching concept based on physical similarity is a general endowment of animals.  相似文献   
25.
Three adult subjects were taught a set of two-choice simultaneous discriminations, with three positive and three negative stimuli; all possible combinations of positive and negative stimuli yielded nine different pairs. The discriminations were repeatedly reversed and rereversed, the former positive stimuli becoming negative and the former negative stimuli becoming positive. With all subjects, a reversal of the contingencies for one pair of stimuli became sufficient to change their responses to all of the other pairs. The reversals had produced functional stimulus classes. Then, all subjects showed conditional discriminations emerging between members of a functional class; given a sample from one class and comparisons from both classes, they selected the comparison that was in the same class as the sample. Next, 2 of the subjects showed that the within-class conditional relations possessed the symmetric and transitive properties of equivalence relations; after having been taught to relate new stimuli to existing class members, the subjects then matched other class members to the new stimuli. Subsequent tests of two-choice discriminations showed that the conditional discriminations had transferred functional class membership to the new stimuli. The 3rd subject, who did not show equivalence relations among functional class members, was also found to have lost the within-class conditional relations after the equivalence tests.  相似文献   
26.
Two studies using a computer-simulated, strategy-formulation game and business students were conducted using simultaneous verbal protocols. It was found that a number of information-processing and information-evaluation thought processes were significantly related to game performance. Consistent with what is known about individual decision making, the present results suggest that, for the task used in this study, individuals who engage in causal analysis perform better than those who do not. But those who focus on negative emotions, blindly repeat previously successful decisions, and engage in illogical through processes perform more poorly than those who do not. Causal replication using real managers within organizational settings, however, is needed before firm conclusions can be drawn from this research.  相似文献   
27.
Within the framework of valence-instrumentality (VI) theory, a fourfold model is developed to predict the contribution which is made by one outcome of an alternative to the valence of that alternative. The proposed model uses four subjective conditional probabilities which are based on the presence and absence of an alternative, and on the occurrence and nonoccurrence of an outcome. Valence is defined as the difference between the attractiveness values of the occurrence of an alternative (or an outcome) and the nonoccurrence of an alternative (or an outcome). Also, differences between subjective probabilities replace instrumentalities. Alternative valence-instrumentality formulations are analyzed in relation to the proposed fourfold model. The proposed model can be understood as a consistent application of Vroom's model (1964, Work and motivation, New York: Wiley), while other models are judged to be relatively deficient. The fourfold model, in combination with a matrix formulation of expectancy concepts, addresses a number of criticisms of VI theory and makes possible a test of the theory within the limits of its own assumptions.  相似文献   
28.
This research investigated the relationships between technology, interdependence, job characteristics, and employee satisfaction, performance, and influence. Technology was operationalized at the individual level of analysis to include the dimensions of input uncertainty, conversion uncertainty, and output uncertainty. Pooled, sequential, and reciprocal interdependence was assessed. The results indicated that input and conversion uncertainty and interdependence were strongly related to such job characteristics as autonomy, skill variety, task identity, task significance, and task feedback. While the job characteristics related positively to employee satisfaction, input and conversion uncertainty related negatively to satisfaction, thus creating a mutual suppression effect. Although the uncertainty dimensions did not relate significantly to performance, there is some evidence that this negative relationship was being suppressed by the positive relationship between job characteristics and performance. Both the job characteristics and the technology dimensions related positively to influence. Results were discussed in terms of appropriate matches between technology and job characteristics.  相似文献   
29.
Tapping rate and variability were measured as 73 normal, right-handed children in Grades 1–4 engaged in speeded unimanual finger tapping with and without concurrent recitation. Speaking reduced the rate of tapping and increased its variability to a greater extent in younger children than in older children. Developmental changes in variability but not rate were attributable to a greater number of lengthy (>500 ms) pauses in the tapping of younger children. Speaking slowed the right hand more than the left, and the degree of this asymmetry was constant across grade levels. The right-hand effect for tapping rate was not attributable to lengthy pauses. In contrast, asymmetric increases in tapping variability occurred only among children in Grade 1 and only when lengthy pauses were included in the data. The results implicate three mechanisms of intertask interference: one involving capacity limitations, a second involving cross-talk between motor control mechanisms for speech and finger movement, respectively, and a third factor involving occasional diversion of attention from tapping to speaking. These mechanisms are discussed in relation to developmental changes in mental capacity.  相似文献   
30.
Subjects in Santa Barbara, California, and Groningen, The Netherlands, participated in a seven-person social dilemma game, presented in terms of a conservation of resources problem. Prior to their decision making in the social dilemma game, subject's social motive (altruistic, cooperative, individualistic, competitive) was assessed by means of two different classification procedures. On the basis of previous research findings American subjects were expected to display relatively more competitive social motives, and Dutch subjects relatively more cooperative ones. However, no indications of crosscultural differences were found neither with regard to the distribution of social motives nor with regard to the amount of resources taken for self in the social dilemma game. In both locations, competitive subjects took most resources for self, individualistic subjects took next most, cooperative subjects took less than individualists, and altruistic subjects took the least. In addition to predictive validity, indices of the convergent validity of two social motive assessment procedures were described.  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