全文获取类型
收费全文 | 20752篇 |
免费 | 418篇 |
国内免费 | 8篇 |
专业分类
21178篇 |
出版年
2021年 | 180篇 |
2020年 | 317篇 |
2019年 | 306篇 |
2018年 | 473篇 |
2017年 | 469篇 |
2016年 | 489篇 |
2015年 | 376篇 |
2014年 | 415篇 |
2013年 | 1652篇 |
2012年 | 778篇 |
2011年 | 809篇 |
2010年 | 487篇 |
2009年 | 455篇 |
2008年 | 612篇 |
2007年 | 620篇 |
2006年 | 491篇 |
2005年 | 423篇 |
2004年 | 420篇 |
2003年 | 388篇 |
2002年 | 394篇 |
2001年 | 763篇 |
2000年 | 770篇 |
1999年 | 514篇 |
1998年 | 218篇 |
1997年 | 201篇 |
1996年 | 164篇 |
1995年 | 157篇 |
1993年 | 160篇 |
1992年 | 382篇 |
1991年 | 341篇 |
1990年 | 375篇 |
1989年 | 363篇 |
1988年 | 338篇 |
1987年 | 312篇 |
1986年 | 329篇 |
1985年 | 319篇 |
1984年 | 254篇 |
1983年 | 218篇 |
1979年 | 218篇 |
1978年 | 174篇 |
1975年 | 209篇 |
1974年 | 266篇 |
1973年 | 213篇 |
1972年 | 217篇 |
1971年 | 180篇 |
1970年 | 170篇 |
1969年 | 204篇 |
1968年 | 217篇 |
1967年 | 175篇 |
1966年 | 192篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
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
2.
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
3.
4.
Wolfgang Hell Gerd Gigerenzer Siegfried Gauggel Maria Mall Michael Müller 《Memory & cognition》1988,16(6):533-538
If subjects are asked to recollect a former response after having been informed about the correct response, their recollection tends to approach the correct response. This effect has been termedhindsight bias. We studied hindsight bias in an experiment requiring numerical responses to almanac-type questions for physical quantities. We varied (1) the time at which the correct information was provided, (2) the encoding of the original responses by asking/not asking subjects to give a reason for the respective response, and (3) the motivation to recall correctly. We found that hindsight is less biased if reasons are given and if the correct information is provided at an earlier time. Motivation had only interactive effects: (1) With high motivation to recall correctly, the time the correct information was provided had no influence. (2) With reasons given, the variation of motivation showed no effect. These results rule out purely motivational and purely automatic explanations. 相似文献
5.
6.
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
7.
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
8.
In two experiments, key-peck responding of pigeons was compared under variable-interval schedules that arranged immediate reinforcement and ones that arranged unsignaled delays of reinforcement. Responses during the nominal unsignaled delay periods had no effect on the reinforcer presentations. In Experiment 1, the unsignaled delays were studied using variable-interval schedules as baselines. Relative to the immediate reinforcement condition, 0.5-s unsignaled delays decreased the duration of the reinforced interresponse times and increased the overall frequency of short (<0.5-s) interresponse times. Longer, 5.0-s unsignaled delays increased the duration of the reinforced interresponse times and decreased the overall frequency of the short interresponse times. In Experiment 2, similar effects to those of Experiment 1 were obtained when the 0.5-s unsignaled delays were imposed upon a baseline schedule that explicitly arranged reinforcement of short interresponse times and therefore already generated a large number of short interresponse times. The results support earlier suggestions that the unsignaled 0.5-s delays change the functional response unit from a single key peck to a multiple key-peck unit. These findings are discussed in terms of the mechanisms by which contingencies control response structure in the absence of specific structural requirements. 相似文献
9.
The effects of two alternative sources of food delivery on the key-peck responding of pigeons were examined. Pecking was maintained by a variable-interval 3-min schedule. In the presence of this schedule in different conditions, either a variable-time 3-min schedule delivering food independently of responding or an equivalent schedule that required a minimum 2-s pause between a key peck and food delivery (a differential-reinforcement-of-other-behavior schedule) was added. The differential-reinforcement-of-other-behavior schedule reduced response rates more than did the variable-time schedule in most instances. The delay between a key peck and the next reinforcer consistently was longer under the differential-reinforcement-of-other-behavior schedule than under the variable-time schedule. Response rates and median delay between responses and reinforcers were negatively correlated. These results contradict earlier conclusions about the behavioral effects of alternative reinforcement. They suggest that an interpretation in terms of response–reinforcer contiguity is consistent with the data. 相似文献
10.
K Friemert 《Psychiatrie, Neurologie, und medizinische Psychologie》1988,40(11):671-677
Basing on the author's experiences during his study stay at the Serbsky All-Union Research Institute for General and Forensic Psychiatry in Moscow a report is given about the theoretical foundations and the carrying-out of forensic-psychiatric expert-opinions in the field of penal as well as civil law in the U.S.S.R. Some peculiarities in comparison with the practice in the G.D.R. are taken in special account. 相似文献