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91.
Simon HJ  Divenyi PL  Lotze A 《Perception》2002,31(7):855-873
The effects of varying interaural time delay (ITD) and interaural intensity difference (IID) were measured in normal-hearing sighted and congenitally blind subjects as a function of eleven frequencies and at sound pressure levels of 70 and 90 dB, and at a sensation level of 25 dB (sensation level refers to the pressure level of the sound above its threshold for the individual subject). Using an 'acoustic' pointing paradigm, the subject varied the IID of a 500 Hz narrow-band (100 Hz) noise (the 'pointer') to coincide with the apparent lateral position of a 'target' ITD stimulus. ITDs of 0, +/-200, and +/-400 micros were obtained through total waveform delays of narrow-band noise, including envelope and fine structure. For both groups, the results of this experiment confirm the traditional view of binaural hearing for like stimuli: non-zero ITDs produce little perceived lateral displacement away from 0 IID at frequencies above 1250 Hz. To the extent that greater magnitude of lateralization for a given ITD, presentation level, and center frequency can be equated with superior localization abilities, blind listeners appear at least comparable and even somewhat better than sighted subjects, especially when attending to signals in the periphery. The present findings suggest that blind listeners are fully able to utilize the cues for spatial hearing, and that vision is not a mandatory prerequisite for the calibration of human spatial hearing.  相似文献   
92.
In the first part of this paper we review evidence suggesting that there exists a mechanism that selects input on the basis of its similarity to the required action. This response-based input selection differs from the more established space- and object-based input selection in that it is not constrained by the structure of the input. Our evidence suggests that the two-choice Stroop effect is caused by this response-based selection mechanism. By contrast, it is known that the flanker effect is determined by the space- and object- based selection mechanisms. We explore whether the conflict resolution of the Stroop and flanker tasks is different as well by embedding these two tasks in a PRP (Psychological Refractory Period) paradigm. We show that the Stroop and the PRP effects are additive whereas the flanker and the PRP effects are underadditive, suggesting that the processes in charge of the conflict resolution in the Stroop and the flanker tasks are indeed different. We discuss possible reasons for this difference, and discuss possible ways in which the response-based mechanism can be implemented in information processing models.  相似文献   
93.
The influence of a genetic risk factor, apolipoprotein E (apoE) epsilon4 variant, was assessed in older adults aged 70 to 94 on 3 occasions over 7 years. The results of latent growth curve analyses are reported for individuals genotyped for apoE at the 2nd measurement occasion (n = 601) and for a subsample of individuals without probable or definite dementia during the 1st or 2nd occasion (n = 434). ApoE-epsilon4 status was a significant predictor of level and change in memory performance and change in speed performance in the full sample, and of initial level and change in memory performance in the nondemented subsample. These results support previous findings that apoE-epsilon4 is associated with accelerated memory deterioration in individuals without clinical dementia.  相似文献   
94.
This article reviews relevant literature as to the labor pool of qualified individuals with disabilities and employment in information technology (IT) sector jobs. First, the article reviews the empirical literature on barriers to employment in IT for persons with disabilities. The examination then is extended to studies of barriers to employment for individuals with disabilities in other employment sectors. Findings illustrate the limited experiences that IT and non-IT companies have in employing and accommodating employees with disabilities. Implications are discussed for enhancing the employment of qualified workers with disabilities in IT through research, education, training, and mentoring programs.  相似文献   
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Numerous previous investigators have explained species differences in spatial memory performance in terms of differences in foraging ecology. In three experiments we attempted to extend these findings by examining the extent to which the spatial memory performance of echidnas (or "spiny anteaters") can be understood in terms of the spatio-temporal distribution of their prey (ants and termites). This is a species and a foraging situation that have not been examined in this way before. Echidnas were better able to learn to avoid a previously rewarding location (to "win-shift") than to learn to return to a previously rewarding location (to "win-stay"), at short retention intervals, but were unable to learn either of these strategies at retention intervals of 90 min. The short retention interval results support the ecological hypothesis, but the long retention interval results do not. Electronic Publication  相似文献   
98.
Scientific misconduct includes the fabrication, falsification, and plagiarism (FFP) of concepts, data or ideas; some institutions in the United States have expanded this concept to include “other serious deviations (OSD) from accepted research practice.” It is the absence of this OSD clause that distinguishes scientific misconduct policies of the past from the “research misconduct” policies that should be the basis of future federal policy in this area. This paper introduces a standard for judging whether an action should be considered research misconduct as distinguished from scientific misconduct: by this standard, research misconduct must involve activities unique to the practice of science and must have the potential to negatively affect the scientific record. Although the number of cases of scientific misconduct is uncertain (only the NIH and the NSF keep formal records), the costs are high in terms of the integrity of the scientific record, diversions from research to investigate allegations, ruined careers of those eventually exonerated, and erosion of public confidence in science. Existing scientific misconduct policies vary from institution to institution and from government agency to government agency; some have highly developed guidelines that include OSD, others have no guidelines at all. One result has been that the federal False Claims Act has been used to pursue allegations of scientific misconduct. As a consequence, such allegations have been adjudicated in federal courts, rather than judged by scientific peers. The federal government is now establishing a first-ever research misconduct policy that would apply to all research funded by the federal government regardless of which agency funded the research or whether the research was carried out in a government, industrial or university laboratory. Physical scientists, who up to now have only infrequently been the subject of scientific misconduct allegations, must nonetheless become active in the debate over research misconduct policies and how they are implemented since they will now be explicitly covered by this new federal wide policy. Disclaimer: The authors are grateful for the support for conduct of this research provided by the United States Department of Energy (DOE). The views expressed in this paper are solely those of the authors and were formed and expressed without reference to positions taken by DOE or the Pacific Northwest National Laboratory (PNNL). The views of the authors are not intended either to reflect or imply positions of DOE or PNNL.  相似文献   
99.
Confirmatory factor analysis and regression analyses of the Beavers Interactional Scales did not appear to support the model offered by its developers, namely, several specified family attributes contributing respectively to two global factors of Family Competence and Family Style. Moreover, regression analysis indicated that only three of 12 items predicted raters' assessments of Global Family Health, and one of seven items predicted Global Family Style. Individuals interested in the family dynamic centripetal/centrifugal might best think of that as a unitary entity and rate it accordingly.  相似文献   
100.
Postmodern sensibilities, generally associated with relational psychoanalysis, are applicable also in traditional and contemporary Freudian psychoanalytic contexts. Historically speaking, views of femininity and female sexuality may be ordered according to positions designated as premodern, modern, and postmodern. This temporal continuum provides a basis for incorporating aspects of postmodern feminist approaches to deconstructing gender into a more traditional yet contemporary psychoanalytic framework. The postmodern "crisis of category" is addressed through a critique from a modern psychoanalytic point of view of the gender stereotyping inherent in certain false binaries and either/or thinking of premodern psychoanalytic thinking regarding female (as well as male) sex and gender. The cultural changes brought about by the consciousness-raising of postmodern feminist and contemporary psychoanalytic thinking contribute significantly to evolutionary changes in the understanding of gender that are further internalized and represented intrapsychically. That is, sequential transformations in the internalization of new cultural norms influence the development of still more new cultural norms, so that progression in these identificatory markers of gender can be observed over successive generations.  相似文献   
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