全文获取类型
收费全文 | 18247篇 |
免费 | 882篇 |
国内免费 | 15篇 |
专业分类
19144篇 |
出版年
2020年 | 256篇 |
2019年 | 281篇 |
2018年 | 394篇 |
2017年 | 420篇 |
2016年 | 419篇 |
2015年 | 313篇 |
2014年 | 349篇 |
2013年 | 1449篇 |
2012年 | 624篇 |
2011年 | 704篇 |
2010年 | 412篇 |
2009年 | 386篇 |
2008年 | 519篇 |
2007年 | 497篇 |
2006年 | 450篇 |
2005年 | 377篇 |
2004年 | 377篇 |
2003年 | 361篇 |
2002年 | 365篇 |
2001年 | 718篇 |
2000年 | 721篇 |
1999年 | 484篇 |
1998年 | 207篇 |
1997年 | 201篇 |
1996年 | 163篇 |
1995年 | 150篇 |
1993年 | 157篇 |
1992年 | 380篇 |
1991年 | 330篇 |
1990年 | 359篇 |
1989年 | 341篇 |
1988年 | 325篇 |
1987年 | 302篇 |
1986年 | 318篇 |
1985年 | 306篇 |
1984年 | 256篇 |
1983年 | 213篇 |
1979年 | 204篇 |
1978年 | 180篇 |
1976年 | 144篇 |
1975年 | 195篇 |
1974年 | 254篇 |
1973年 | 202篇 |
1972年 | 207篇 |
1971年 | 170篇 |
1970年 | 150篇 |
1969年 | 201篇 |
1968年 | 205篇 |
1967年 | 163篇 |
1966年 | 188篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
The present study is concerned with the perceptual information about the body and space underlying the act of catching a ball. In a series of four experiments, subjects were asked to catch a luminous ball under various visual conditions. In general, catching in a normally illuminated room was contrasted with catching the luminous ball in an otherwise completely dark room. In the third and fourth experiments, intermediate conditions of visual information were included. The results suggest that it is possible to catch a ball with one hand when only the ball is visible, but performance is better when the subject has the benefit of a rich visual environment and two hands. The second experiment indicated that subject performance does improve with practice in the dark, but time spent in the darkened room itself doesn't result in a significant decrement in performance. Results of the third study suggest that vision of one's hand does not aid in the performance of this task whereas the presence of a minimal visual frame appears to aid performance. The final study examined the relation between catching performance and body sway under similar visual conditions. Results of this experiment imply that persons who exhibit relatively little postural sway in full-room lighting performed better at this catching task. 相似文献
32.
The influence of positive and negative moods on children's recall and recognition memory and impression-formation judgments was investigated in a two-list experimental design. A total of 161 schoolchildren, 8 to 10 years old, were presented with audiovisual information containing positive and negative details about 2 target children. Each presentation was preceded by happy or sad mood manipulations. One day later, the children were again placed in a happy or sad mood, and their recall and recognition memory and impression-formation judgments were assessed. Results showed that memory was better when (a) the children felt happy during encoding, retrieval, or both; (b) the material was incongruent with learning mood; (c) the 2 target characters were encountered in contrasting rather than in matching mood states; and (d) recall mood matched encoding mood. A happy mood increased the extremity of both positive and negative impression-formation judgments. Results are contrasted with experimental data obtained with normal or depressed adults, and implications are considered for contemporary theories of mood effects on cognition and for social-developmental research. 相似文献
33.
Speech nonfluency in response to questions about the marital relationship was used to assess anxiety. Subjects were 31 husbands and 31 wives, all white, college educated, from middle- to lower-middle-class families, and ranging from 20 to 30 years of age. Three types of nonfluencies were coded: filled pauses, unfilled pauses, and repetitions. Speech-disturbance ratios were computed by dividing the sum of speech nonfluencies by the total words spoken. The results support the notion that some issues within marriage are more sensitive and/or problematic than others, and that, in an interview situation, gender interacts with question content in the production of nonfluencies. 相似文献
34.
A D Pick C F Palmer B L Hennessy M G Unze R K Jones R M Richardson 《Journal of experimental child psychology》1988,45(1):28-51
Children's perception of scale and contour in melodies was investigated in five studies. Experimental tasks included judging transposed renditions of melodies (Studies 1 and 3), discriminating between transposed renditions of a melody (Study 2), judging contour-preserving transformations of melodies (Study 4), and judging similarity to a familiar target melody of transformations preserving rhythm or rhythm and contour (Study 5). The first and second studies showed that young children detect key transposition changes even in familiar melodies and they perceive similarity over key transpositions even in unfamiliar melodies. Young children also are sensitive to melodic contour over transformations that preserve it (Study 5), yet they distinguish spontaneously between melodies with the same contour and different intervals (Study 4). The key distance effect reported in the literature did not occur in the tasks of this investigation (Studies 1 and 3), and it may be apparent only for melodies shorter or more impoverished than those used here. 相似文献
35.
Although peers' and teachers' evaluations of children's prosocial behavior and peers' sociometric ratings frequently have been used in studies of social development, the validity of young children's ratings of others has been questioned, as has that for teachers' ratings of prosocial behavior. In this study, preschoolers' ratings of peers' sociometric status and prosocial behavior, as well as teachers' ratings of children's prosocial dispositions, were obtained. These were correlated with children's naturally occurring prosocial or social behavior; ratings of prosocial behavior also were correlated with children's prosocial moral reasoning and prosocial self-attributions. Peers' sociometric ratings were positively related to children's sociability whereas prosocial ratings were related to helping (but not sharing) behavior. Teachers' ratings of prosocial behavior were not related to frequency of prosocial behaviors, but were positively related to developmentally mature moral judgments and self-reported motives. 相似文献
36.
Training in systemic therapy necessitates a structured approach to teaching systemic thinking. The Systemic Therapy Sessions Summary Form, a record-keeping method, is presented as a tool for enhancing training in systemic therapy. The purpose of this form is to provide the structure for the trainee to develop circular hypotheses, to connect reflexively the assessment and intervention components of therapy, and to maintain a sense of the evolving nature of therapy across sessions. A case example illustrates the use of this record-keeping format. 相似文献
37.
38.
39.
Serotonergic and opiate interactions in the modulation of drug- and environmental-induced analgesia were assessed in 6-day-old Sprague-Dawley-derived rat pups using tail-flick testing procedures. In these experiments the serotonergic antagonist metergoline was observed to attenuate both the analgesia induced by the opiate agonist morphine and the analgesia induced by isolation from siblings and the dam, an environmental manipulation which has previously been shown to be associated with increases in opiate activity. In contrast, the opiate antagonist naloxone was observed to be ineffective in blocking not only analgesia induced by the serotonergic agonist quipazine, but also analgesia induced by long-term deprivation from the dam and food, a manipulation that has been previously reported to induce increases in serotonergic utilization. These results suggest that in the neonate, as in the adult, the serotonergic modulation of nociception appears to occur "downstream" from the opiate systems serving to regulate nociception following both drug- and environmental-induced alterations in pain sensitivity. Analgesia induced by long-term deprivation from food and the dam appears to be strongly related to increases in serotonergic activity and relatively unaffected by opiate antagonism, whereas analgesia induced by isolation from siblings and the dam may be related to increases in opiate activity, but modulated by serotonergic systems serving to regulate pain responsivity. Thus alterations in the environment, mediated at least in part by alterations in opiate and serotonergic activity, appear to play an important role in influencing the sensitivity of the neonate to pain stimuli. 相似文献
40.
Paul K. Moser 《Erkenntnis》1988,28(2):231-251
Epistemological probability is the kind of probability relative to a body of evidence. Many philosophers, including Henry Kyburg and Roderick Chisholm, hold that all epistemological probabilities reflect a relation between an evidential body of propositions and other propositions. But this article argues that some epistemological probabilities for empirical propositions must be relative to non-propositional evidence, specifically the contents of non-propositional perceptual states. In doing so, the article distinguishes between internalism and externalism regarding epistemological probability, and argues for a version of awareness internalism. The article draws three main concluding lessons. First, epistemological probability is not to be identified with the sort of objective, experience-independent probability that is familiar from statistical and propensity interpretations of probability. Second, it is doubtful that epistemological probability is measurable, in any useful way, by real numbers, even if it admits of comparative assessments. Third, contrary to the familiar claim of C. I. Lewis, epistemological probability should not be viewed as requiring a basis of certainty. 相似文献