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821.
Tests of psychomotor and motor speed at different levels of complexity were studied in random samples of men aged 31 to 35, 51 to 55, and 71 to 75 yr. The study was performed as a part of a larger research project on health and functional aging. Analyses indicated significantly slower responses among older men at all levels of test complexity (maximal knee extension velocity, tapping rate, simple and choice reaction and movement times). There were marked differences both between the youngest and the middle-aged groups and between the middle-aged and the oldest groups. Within the age groups high psychomotor and motor speed were associated with a favourable functioning of certain senses (vibration sensitivity and postural balance), with a high isometric muscular force, and with a high directly assessed aerobic capacity. The most important covariants of the speed functions within the age groups were, however, cognitive performance, length of education, and perceived health. 相似文献
822.
E C Lechelt 《Perceptual and motor skills》1986,62(2):356-358
A case is made for the use of tactile-vibratory stimulation in devising sensory-substitution systems for sensorily impaired humans. 相似文献
823.
R H Pindzola 《Perceptual and motor skills》1986,62(2):399-405
Movement rates of formant frequencies and the extents of articulatory change were spectrographically analyzed in the fLuent (VCV) utterances of 20 stutterers and nonstutterers. The velocities of articulator movement throughout the first vowel and velocities into the second vowel were not significantly different for the two groups. These mean rates of movement, although nonsignificant, were slower in stutterers and slightly more variable, and the extent of articulator movement was comparable. These results do not support the contentions that stutterers use coarticulatory movements that are too rapid or that stutterers have a poorer competence for rapid coordination of speech movements. The rationales of rate-control treatment methods to slow coarticulatory movements in stutterers need to be reexamined. 相似文献
824.
H M Knoff 《Perceptual and motor skills》1986,62(2):391-396
The performance of 81 gifted elementary students on the Visual Aural Digit Span test is discussed. The students generally showed advanced performance from Grade 1 through Grade 5 and from age 7-0 yr. through 11-11 yr. Performance at Grade 6 and the 12-0 to 12-11-yr.-old levels were generally at age-expected levels and were probably restricted due to the test's limited ceiling. Tables of means across grade and age and needs for further research are also presented. 相似文献
825.
Bandler and Grinder's hypothesis that eye-movements reflect sensory processing was examined. 28 volunteers first memorized and then recalled visual, auditory, and kinesthetic stimuli. Changes in eye-positions during recall were videotaped and categorized by two raters into positions hypothesized by Bandler and Grinder's model to represent visual, auditory, and kinesthetic recall. Planned contrast analyses suggested that visual stimulus items, when recalled, elicited significantly more upward eye-positions and stares than auditory and kinesthetic items. Auditory and kinesthetic items, however, did not elicit more changes in eye-position hypothesized by the model to represent auditory and kinesthetic recall, respectively. 相似文献
826.
827.
In some recent papers, the authors and Peter Gärdenfors have defined and studied two different kinds of formal operation, conceived as possible representations of the intuitive process of contracting a theory to eliminate a proposition. These are partial meet contraction (including as limiting cases full meet contraction and maxichoice contraction) and safe contraction. It is known, via the representation theorem for the former, that every safe contraction operation over a theory is a partial meet contraction over that theory. The purpose of the present paper is to study the relationship more finely, by seeking an explicit map between the component orderings involved in each of the two kinds of contraction. It is shown that at least in the finite case a suitable map exists, with the consequence that the relational, transitively relational, and antisymmetrically relational partial meet contraction functions form identifiable subclasses of the safe contraction functions, over any theory finite modulo logical equivalence. In the process of constructing the map, as the composition of four simple transformations, mediating notions of bottom and top contraction are introduced. The study of the infinite case remains open. 相似文献
828.
This paper discusses thecompatibility of the polychotomous Rasch model with dichotomization of the response continuum. It is argued that in the case of graded responses, the response categories presented to the subject are essentially an arbitrary polychotomization of the response continuum, ranging for example from total rejection or disagreement to total acceptance or agreement of an item or statement. Because of this arbitrariness, the measurement outcome should be independent of the specific polychotomization applied, for example, presenting a specific multicategory response format should not affect the measurement outcome. When such is the case, the original polychotomous model is called compatible with dichotomization.A distinction is made between polychotomization or dichotomization before the fact, that is, in constructing the response format, and polycho- or dichotomization after the fact, for example in dichotomizing existing graded response data.It is shown that, at least in case of dichotomization after-the-fact, the polychotomous Rasch model is not compatible with dichotomization, unless a rather special condition of the model parameters is met. Insofar as it may be argued that dichotomization before the fact is not essentially different from dichotomization after the fact, the value of the unidimensional polychotomous Rasch model is consequently questionable. The impact of our conclusion on related models is also discussed. 相似文献
829.
Frits E. Zegers 《Psychometrika》1986,51(4):559-562
A chance-corrected version of the family of association coefficients for metric scales proposed by Zegers and ten Berge is
presented. It is shown that a matrix with chance-corrected coefficients between a number of variables is Gramian. The members
of the chance-corrected family are shown to be partially ordered.
The author is obliged to Jos ten Berge for helpful comments. 相似文献
830.