全文获取类型
收费全文 | 3770篇 |
免费 | 199篇 |
国内免费 | 1篇 |
专业分类
3970篇 |
出版年
2024年 | 10篇 |
2023年 | 50篇 |
2022年 | 42篇 |
2021年 | 78篇 |
2020年 | 91篇 |
2019年 | 134篇 |
2018年 | 156篇 |
2017年 | 156篇 |
2016年 | 160篇 |
2015年 | 127篇 |
2014年 | 123篇 |
2013年 | 438篇 |
2012年 | 238篇 |
2011年 | 237篇 |
2010年 | 137篇 |
2009年 | 108篇 |
2008年 | 170篇 |
2007年 | 151篇 |
2006年 | 114篇 |
2005年 | 136篇 |
2004年 | 131篇 |
2003年 | 126篇 |
2002年 | 90篇 |
2001年 | 62篇 |
2000年 | 72篇 |
1999年 | 46篇 |
1998年 | 33篇 |
1997年 | 25篇 |
1996年 | 26篇 |
1995年 | 20篇 |
1994年 | 12篇 |
1993年 | 24篇 |
1992年 | 31篇 |
1991年 | 32篇 |
1990年 | 38篇 |
1989年 | 25篇 |
1988年 | 30篇 |
1987年 | 26篇 |
1986年 | 31篇 |
1985年 | 28篇 |
1984年 | 25篇 |
1983年 | 19篇 |
1982年 | 9篇 |
1980年 | 9篇 |
1979年 | 13篇 |
1978年 | 12篇 |
1977年 | 13篇 |
1974年 | 12篇 |
1971年 | 8篇 |
1968年 | 8篇 |
排序方式: 共有3970条查询结果,搜索用时 0 毫秒
41.
W. M. de Muynck 《Synthese》1995,102(2):293-318
The axiomatic approaches of quantum mechanics and relativity theory are compared with approaches in which the theories are thought to describe readings of certain measurement operations. The usual axioms are shown to correspond with classes of ideal measurements. The necessity is discussed of generalizing the formalisms of both quantum mechanics and relativity theory so as to encompass more realistic nonideal measurements. It is argued that this generalization favours an empiricist interpretation of the mathematical formalisms over a realist one. 相似文献
42.
Scientific Discovery A. Kantorovich 1993 New York, State University of New York Press $17.95
A Model of the Universe Storrs McCall, 1994 Clarendon Press, Oxford 288pp. plus 15pp. appendices, plus 14pp. references plus index 0198240538 £30.00
Explanation David Hillel Ruben (ed. 1993) Oxford University Press pp vi + 365 ISBN 019875129X. Pb £9.95, Hb £27.50 相似文献
43.
Vilhjálmur Árnason 《Theoretical medicine and bioethics》1994,15(3):227-242
The purpose of this paper is to evaluate the significance of the existential notion of authenticity for medical ethics. This is done by analyzing authenticity and examining its implications for the patient-professional relationship and for ethical decision-making in medical situations. It is argued that while authenticity implies important demand for individual responsibility, which has therapeutic significance, it perpetuates ideas which are antithetical both to authentic interaction between patients and professionals and to fruitful deliberation of moral dilemmas. In order to counteract these consequences, an alternative idea of authenticity is introduced. According to this idea, authenticity is not regarded primarily as individual sovereignty, but as an ability to participate in a dialogue in which the subjectivity of both partners is respected. Such practice, based on mutual trust and responsibility, would enhance common decision-making and overcome the alienation between patients and professionals. 相似文献
44.
45.
Peter Suedfeld Brian de Vries Susan Bluck Alistair B. C. Wallbaum Paul W. Schmidt 《International journal of psychology》1996,31(5):177-190
Although there are measurable differences in integrative complexity among solutions that individuals generate in dealing with problems, it is uncertain to what extent people comprehend, recognize, and have preferences among different levels of complexity. Integrative complexity is a function of differentiation (the perception of several attributes within, or perspectives about, a topic) and integration (combining the differentiated characteristics in an interactive or synthesizing solution). The current paper reports two experiments dealing with how university students perceive, interpret, and choose among solutions differing in complexity. Experiment 1 showed that subjects accurately rated the complexity of described solutions differing along the continuum, but that their assessment of their own responses differed from the results of expert scoring. Their self-estimated complexity was highly correlated with their preferences, and preferred complexity was reliably higher than either expert- or self-assessed complexity of subject-generated solutions. Subjects were able to hypothesize quite accurately about environmental and endogenous factors likely to affect complexity. Experiment 2 found that in response to problem scenarios, solutions selected as being potentially most effective were consistently more complex than solutions that participants considered themselves most likely to use. The idea of complexity seems to be intuitively recognizable and understandable by untrained subjects: They can and do distinguish among problem solutions (self-generated or presented) that vary on that dimension, and are able to assess accurately the effects of relevant variables. Such subjects also share the bias shown by experts in favour of the superiority of more complex approaches. 相似文献
46.
Idsart Kingma Michiel P. de Looze Huub M. Toussaint Hans G. Klijnsma Tom B.M. Bruijnen 《Human movement science》1996,15(6):833-860
In studies related to human movement, linked segment models (LSM's) are often used to quantify forces and torques, generated in body joints. Some LSM's represent only a few body segments. Others, for instance used in studies on the control of whole body movements, include all body segments. As a consequence of the complexity of 3-dimensional (3-D) analyses, most LSM's are restricted to one plane of motion. However, in asymmetric movements this may result in a loss of relevant information. The aim of the current study was to develop and validate a 3-D LSM including all body segments. Braces with markers, attached to all body segments, were used to record the body movements. The validation of the model was accomplished by comparing the measured with the estimated ground reaction force and by comparing the torques at the lumbo-sacral joint that resulted from a bottom-up and a top-down mechanical analysis. For both comparisons, reasonable to good agreement was found. Sources of error that could not be analysed this way, were subjected to an additional sensitivity analysis. It was concluded that the internal validity of the current model is quite satisfactory. 相似文献
47.
Two experiments were carried out in order to try to resolve the controversy about whether the semantic processing of a word necessarily involves all the elements of its meaning. In the first experiment, subjects categorized a list of auditorially presented words according to whether or not they were natural consumable solids (e.g., “apple“). They were then given an unexpected test of their ability to recall the whole list, which contained equal numbers of words with none, one, two, or all three of the target components. The results confirmed the prediction that the greater the number of components a word has in common with a target category, the better it will be recalled. The second experiment used a visual presentation of a list of words, which subjects scanned for members of a particular target category. There were four different target categories assigned to independent groups of subjects. The results again confirmed the prediction. On the assumption that memorability in such tasks is determined by amount of processing, we conclude that some elements of the meaning of a word can be processed without having to process all of them. 相似文献
48.
This paper describes a computational method for weighted euclidean distance scaling which combines aspects of an analytic solution with an approach using loss functions. We justify this new method by giving a simplified treatment of the algebraic properties of a transformed version of the weighted distance model. The new algorithm is much faster than INDSCAL yet less arbitrary than other analytic procedures. The procedure, which we call SUMSCAL (subjectivemetricscaling), gives essentially the same solutions as INDSCAL for two moderate-size data sets tested.Comments by J. Douglas Carroll and J. B. Kruskal have been very helpful in preparing this paper. 相似文献
49.
S. A. Corson E. O’L. Corson R. E. Becker B. E. Ginsburg A. Trattner R. L. Connor L. A. Lucas J. Panksepp J. P. Scott 《Integrative psychological & behavioral science》1980,15(1):5-11
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
50.