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   1109篇
  免费   45篇
  2023年   7篇
  2022年   12篇
  2021年   14篇
  2020年   15篇
  2019年   29篇
  2018年   32篇
  2017年   31篇
  2016年   48篇
  2015年   31篇
  2014年   25篇
  2013年   162篇
  2012年   58篇
  2011年   54篇
  2010年   29篇
  2009年   25篇
  2008年   31篇
  2007年   47篇
  2006年   40篇
  2005年   35篇
  2004年   32篇
  2003年   33篇
  2002年   36篇
  2001年   14篇
  2000年   28篇
  1999年   13篇
  1998年   11篇
  1997年   16篇
  1996年   7篇
  1995年   7篇
  1994年   14篇
  1993年   11篇
  1992年   10篇
  1990年   9篇
  1989年   11篇
  1988年   9篇
  1987年   14篇
  1986年   9篇
  1985年   14篇
  1984年   7篇
  1983年   8篇
  1982年   10篇
  1981年   13篇
  1980年   11篇
  1979年   8篇
  1978年   7篇
  1974年   6篇
  1973年   6篇
  1969年   4篇
  1968年   5篇
  1967年   4篇
排序方式: 共有1154条查询结果,搜索用时 15 毫秒
51.
Social Psychology of Education - Teacher expectation research has continued to establish an association between what teachers expect of their students and what students accomplish academically....  相似文献   
52.
Three experiments showed that constraints imposed early in learning have different effects on variability when they are in effect and after they are removed. Task constraints, which determine how something can be done, limited the number of possible responses in a computer game. Variability constraints, which specify how differently something must be done, required that each response differ from some number of prior responses. Less restrictive constraints (Experiments 1 and 2) produced higher variability during the constraints. More restrictive constraints (Experiments 2 and 3) led to higher variability after the constraints were relaxed. The authors discuss how these differences reflect strategies acquired during the constraints (default rules) and modified in closely related ways (exception rules) afterward.  相似文献   
53.
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   
54.
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   
55.
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   
56.
57.
58.
The average probability estimate of J > 1 judges is generally better than its components. Two studies test 3 predictions regarding averaging that follow from theorems based on a cognitive model of the judges and idealizations of the judgment situation. Prediction 1 is that the average of conditionally pairwise independent estimates will be highly diagnostic, and Prediction 2 is that the average of dependent estimates (differing only by independent error terms) may be well calibrated. Prediction 3 contrasts between- and within-subject averaging. Results demonstrate the predictions' robustness by showing the extent to which they hold as the information conditions depart from the ideal and as J increases. Practical consequences are that (a) substantial improvement can be obtained with as few as 2-6 judges and (b) the decision maker can estimate the nature of the expected improvement by considering the information conditions.  相似文献   
59.
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   
60.
Both the interrater and test-retest-retest reliability of axis I and axis II disorders were assessed using the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) and the Diagnostic Interview for DSM-IV Personality Disorders (DIPD-IV). Fair-good median interrater kappa (.40-.75) were found for all axis II disorders diagnosed five times or more, except antisocial personality disorder (1.0). All of the test-retest kappa for axis II disorders, except for narcissistic personality disorder (1.0) and paranoid personality disorder (.39), were also found to be fair-good. Interrater and test-retest dimensional reliability figures for axis II were generally higher than those for their categorical counterparts; most were in the excellent range (> .75). In terms of axis I, excellent median interrater kappa were found for six of the 10 disorders diagnosed five times or more, whereas fair-good median interrater kappa were found for the other four axis I disorders. In general, test-retest reliability figures for axis I disorders were somewhat lower than the interrater reliability figures. Three test-retest kappa were in the excellent range, six were in the fair-good range, and one (for dysthymia) was in the poor range (.35). Taken together, the results of this study suggest that both axis I and axis II disorders can be diagnosed reliably when using appropriate semistructured interviews. They also suggest that the reliability of axis II disorders is roughly equivalent to that reliability found for most axis I disorders.  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