全文获取类型
收费全文 | 198728篇 |
免费 | 8614篇 |
国内免费 | 155篇 |
专业分类
207497篇 |
出版年
2020年 | 2811篇 |
2019年 | 3475篇 |
2018年 | 3914篇 |
2017年 | 4276篇 |
2016年 | 4902篇 |
2015年 | 3962篇 |
2014年 | 4823篇 |
2013年 | 23530篇 |
2012年 | 5558篇 |
2011年 | 4898篇 |
2010年 | 4304篇 |
2009年 | 4996篇 |
2008年 | 4874篇 |
2007年 | 4519篇 |
2006年 | 4837篇 |
2005年 | 4669篇 |
2004年 | 4219篇 |
2003年 | 3794篇 |
2002年 | 3592篇 |
2001年 | 4718篇 |
2000年 | 4468篇 |
1999年 | 3960篇 |
1998年 | 2964篇 |
1997年 | 2760篇 |
1996年 | 2666篇 |
1995年 | 2494篇 |
1994年 | 2463篇 |
1993年 | 2421篇 |
1992年 | 3280篇 |
1991年 | 3096篇 |
1990年 | 2963篇 |
1989年 | 2814篇 |
1988年 | 2770篇 |
1987年 | 2735篇 |
1986年 | 2743篇 |
1985年 | 2945篇 |
1984年 | 2876篇 |
1983年 | 2597篇 |
1982年 | 2479篇 |
1981年 | 2424篇 |
1980年 | 2280篇 |
1979年 | 2647篇 |
1978年 | 2419篇 |
1977年 | 2319篇 |
1976年 | 2141篇 |
1975年 | 2319篇 |
1974年 | 2490篇 |
1973年 | 2397篇 |
1972年 | 1929篇 |
1971年 | 1856篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Tests of central auditory function and measures of receptive and expressive language abilities were administered to 10 children suspected of having central auditory processing disorders. Eight of the 10 subjects displayed expressive language difficulties, suggesting a need to examine more closely the relationship between expressive language and central auditory processing. 相似文献
972.
A group of 10 educable mentally impaired children (M age = 10 yr., 4 mo.) were assessed for use of phonological process under three speaking conditions: production of single words, imitated sentences, and connected speech samples. Only the process of gliding showed significant differences in use among conditions. Results generally indicated that any of those three speaking conditions were viable for eliciting use of phonological processes by such subjects. Results are also discussed in terms of individual differences. 相似文献
973.
M J Urban 《Perceptual and motor skills》1992,74(2):515-541
Unconscious or subliminal perception has historically been a thorny issue in psychology. It has been the subject of debate and experimentation since the turn of the century. While psychologists now agree that the phenomenon of visual subliminal stimulation is real, disagreement continues over the effects of such stimulation as well as to its existence in other sensory modalities, notably the auditory. The present paper provides an overview of unresolved issues in auditory subliminal stimulation which explains much of the difficulty that has been encountered in experimental work in this area. A context is proposed for considering the effects of auditory subliminal stimulation and an overview of current investigations in this field is provided. 相似文献
974.
This investigation was conducted to examine whether older adults would improve their performance when given statements intended to make them feel important to a research study as well as statements concerning their over-all well-being. Women (n = 14) and men (n = 15) with mean ages of 76.0 yr. and 75.1 yr., respectively, were randomly assigned into a control group, a positive reinforcement group, and a group given statements of personal importance. Dependent measures on a rotary pursuit task, screw-and-nut assembly task, and an interest questionnaire were obtained during three separate visits. Data were analyzed with a 3 x 3 (Groups x Days) analysis of variance. While no significant group effects were found on any measure, a significant main effect was obtained for days, indicative of learning. 相似文献
975.
A soft contact-lens system for achieving unilateral visual stimulation in a free vision format is described. Initial testing with light transmittance and visual perimetry indicated that the lenses created artificial visual-field deficits. The efficacy of the lenses as a technique for lateralizing visual input was evaluated by examining within-subject differences in performance on two visuospatial tasks. Speed and accuracy of performance were greater with visual input directed to the right hemisphere. These data support the lens design as a useful alternative to tachistoscopic procedures and previous lens systems. 相似文献
976.
Differences in visual-motor tracking by 8- to 9-yr.-old boys diagnosed with Minimal Brain Dysfunction or healthy have been analyzed. The subject's task was to use two computer keys to control a cursor line within a target which moved horizontally in two directions over the display. Target size and speed were the experimental variables. Off-target incidences and durations were measured and evaluated. The latter were longer and the former were more frequent on small targets for boys with brain dysfunction than for healthy boys. The two measures correlated negatively in most situations. The perceptual-motor style expressed by means of the distribution of coincidences of the two measures being over or under a criterion set equal to the corresponding averages of the healthy boys was different in the two groups. Brain-damaged boys were characterized mostly by the combination of high incidence of low duration misses for small and fast targets and by high incidence of high duration misses for large and slow targets, whereas most healthy boys showed a few misses of low duration for large and slow targets and few misses of high duration for small and fast targets. 相似文献
977.
This paper suggests a method to supplant missing categorical data by reasonable replacements. These replacements will maximize the consistency of the completed data as measured by Guttman's squared correlation ratio. The text outlines a solution of the optimization problem, describes relationships with the relevant psychometric theory, and studies some properties of the method in detail. The main result is that the average correlation should be at least 0.50 before the method becomes practical. At that point, the technique gives reasonable results up to 10–15% missing data.We thank Anneke Bloemhoff of NIPG-TNO for compiling and making the Dutch Life Style Survey data available to use, and Chantal Houée and Thérèse Bardaine, IUT, Vannes, France, exchange students under the COMETT program of the EC, for computational assistance. We also thank Donald Rubin, the Editors and several anonymous reviewers for constructive suggestions. 相似文献
978.
979.
980.
Deborah G. Mayo 《Synthese》1992,90(2):233-262
I document some of the main evidence showing that E. S. Pearson rejected the key features of the behavioral-decision philosophy that became associated with the Neyman-Pearson Theory of statistics (NPT). I argue that NPT principles arose not out of behavioral aims, where the concern is solely with behaving correctly sufficiently often in some long run, but out of the epistemological aim of learning about causes of experimental results (e.g., distinguishing genuine from spurious effects). The view Pearson did hold gives a deeper understanding of NPT tests than their typical formulation as accept-reject routines, against which criticisms of NPT are really directed. The Pearsonian view that emerges suggests how NPT tests may avoid these criticisms while still retaining what is central to these methods: the control of error probabilities.A portion of this research was carried out during tenure of a National Endowment for the Humanities Summer Stipend Fellowship; I gratefully acknowledge that support. A version of this paper was presented at the 1987 meeting of the Society for Exact Philosophy. This paper benefited from discussions and communications with George Barnard and Isaac Levi. I thank Harlan Miller for helpful comments on earlier drafts. 相似文献