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301.
The research was intended to identify the dimensions underlying self-perceived information needs and concerns of an elderly population. The spontaneously mentioned needs and concerns expressed in 271 letters from a sample of the population were extracted and a multidimensional scaling procedure was used to represent the 58 most frequently mentioned items in configurations of varying dimensionality. To interpret the multidimensional spaces, another sample of 176 elderly subjects was asked to rate the 58 concerns on eight properties. These ratings were then regressed onto the multidimensional configurations. The results indicate that the most frequently mentioned information needs and concerns of elderly persons can be parsimoniously understood in terms of three underlying dimensions: (1) Improving the Quality of Life vs Securing the Necessities of Life, (2) Health-related vs Not Health-related, and (3) Individual vs Societal Responsibility.  相似文献   
302.
The purpose of this study was to assess the relative interrelationships of age, sex, and depth of sport experience on initial practice of a soccer task for 46 4- to 9-yr.-old children. Each child practiced 1 transfer trial and 3 blocks of 3 trials. Measures recorded were performance time, goal attainment, and movement accuracy. Multivariate analyses of variance and multiple regressions yielded evidence for (a) a speed-accuracy tradeoff, (b) a relation of age to goal attainment, movement accuracy, and performance time on the transfer trial, and (c) a relation of age with Block 1 performance time. Experience was more related than sex to all variables except movement accuracy in Block 1 and consistency of goal attainment. Conclusions are that age and experience are the most important to the quality of performance, and no constructs were related to consistency on this task for this age group.  相似文献   
303.
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   
304.
The extraction of three-dimensional shape from shading is one of the most perceptually compelling, yet poorly understood, aspects of visual perception. In this paper, we report several new experiments on the manner in which the perception of shape from shading interacts with other visual processes such as perceptual grouping, preattentive search ("pop-out"), and motion perception. Our specific findings are as follows: (1) The extraction of shape from shading information incorporates at least two "assumptions" or constraints--first, that there is a single light source illuminating the whole scene, and second, that the light is shining from "above" in relation to retinal coordinates. (2) Tokens defined by shading can serve as a basis for perceptual grouping and segregation. (3) Reaction time for detecting a single convex shape does not increase with the number of items in the display. This "pop-out" effect must be based on shading rather than on differences in luminance polarity, since neither left-right differences nor step changes in luminance resulted in pop-out. (4) When the subjects were experienced, there were no search asymmetries for convex as opposed to concave tokens, but when the subjects were naive, cavities were much easier to detect than convex shapes. (5) The extraction of shape from shading can also provide an input to motion perception. And finally, (6) the assumption of "overhead illumination" that leads to perceptual grouping depends primarily on retinal rather than on "phenomenal" or gravitational coordinates. Taken collectively, these findings imply that the extraction of shape from shading is an "early" visual process that occurs prior to perceptual grouping, motion perception, and vestibular (as well as "cognitive") correction for head tilt. Hence, there may be neural elements very early in visual processing that are specialized for the extraction of shape from shading.  相似文献   
305.
The purpose of the present study was to analyse the arousing effects of noise on sleep inertia as a function of circadian placement of a one-hour nap. In a first experiment, we measured the effects of sleep inertia in a neutral acoustic environment after a one-hour nap placed either at 0100 or 0400 on response time during a spatial memory test. In a second experiment were analysed the effects of an intense continuous noise on sleep inertia. The results showed that noise produced a total abolition of sleep inertia after an early nap (0000 to 0100). This may be due to the arousing effect of noise; however, results are less clear after a late nap 0300 to 0400 as noise seems to be ineffective. This result is discussed in terms of either a function of time-of-day effect or of prior sleep intensity. Moreover, our data suggest a possible interaction of noise with partial sleep deprivation leading to a slight deleterious effect those subjects who did not sleep at all.  相似文献   
306.
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   
307.
Several theories on emotion and mood have stressed the close relationship between emotion and motivation. However, assumptions on mood contingent motivations have mainly been studied in the field of social behavior, and there are only few studies concerned with mood contingent task motivations, an area in which nit is possible to distinguish between two motivational sets, the deliberative and the implemented mind set. Assuming that positive mood is associated with a stronger task-oriented deliberative mind set, and that negative mood is associated with a stronger self-oriented deliberative mind set, and that implemented mind set should be intrinsically task-oriented during positive mood and instrumentally task-oriented during negative mood. The present paper is concerned with these assumptions from a subjective perspective: The respondents were asked about their lay perceptions of mood influences (positive, elated versus negative, sad mood) on task related motivations. In study I the respondents (N = 40) were asked about their deliberative mind sets during positive versus negative mood and about their general perceptions of mood influences on performance. In study II the respondents (N = 58) were requested to imagine situations which elicit positive, negative or neutral mood, and then to answer questions on deliberative and implemented mind sets during these states; they also hat to answer a general question about mood influences on task performance. Both quantitative and qualitative measures are used in these studies. The findings support the above general notions, and they additionally show that in the respondents' opinions negative mood effects are more variable than positive mood effects; further, that there are quite a few individual differences in assumed mood effects on task-related motivation.  相似文献   
308.
This study explored the relationship between individual strategies of coping and blood pressure responses during and after mental stress. Blood pressure behavior was measured noninvasively and continuously before, during and after a mental stress situation in 27 normotensive subjects. Coping strategies were assessed with the Stressverarbeitungsfragebogen (SVF; coping with stress inventory). Two extreme groups were formed on the basis of the scores in the SVF. Results were: (a) Individuals who used coping strategies characterized by controlling the situation directly and constructively, in contrast to probands not using these strategies, exhibited lower blood pressure during the stress situation and a faster return to baseline levels after cessation of stress. (b) Subjects using a coping behavior characterized by the use of defense mechanisms such as suppression and denial, also showed lower blood pressure during stress but a significantly delayed return to baseline levels of blood pressure after stress was concluded.  相似文献   
309.
A series of experiments investigated whether people could integrate nonspatial information about an object with their knowledge of the object's location in space. In Experiments 1 and 3, subjects learned the locations of cities on a fictitious road map; in Experiments 2, 4, and 5, subjects were already familiar with the locations of buildings on a campus. The subjects then learned facts about the cities on the maps or the buildings on the campus. The question of interest was whether or not these nonspatial facts would be integrated in memory with the spatial knowledge. After learning the facts, subjects were given a location-judgment test in which they had to decide whether an object was in one region of the space or another. Knowledge integration was assessed by comparing levels of performance in two conditions: (a) when a city or a building name was primed by a fact about a neighboring city or building, and (b) when a city or a building name was primed by a fact about a distant city or building. Results showed that responses in Condition a were faster or more accurate, or both faster and more accurate, than responses in Condition b. These results indicate that the spatial and nonspatial information were encoded in a common memory representation.  相似文献   
310.
Two studies compared the relative strength of motivational assumptions drawn from SIT (e.g. Tajfel, 1978) and memory-based assumptions drawn from the differential familiarity hypothesis (Linville, Fischer and Salovey, 1989) in explaining ingroup bias and the black sheep effect (Marques, 1986, 1990). In Study 1, 15 subjects estimated member distributions and gave overall ratings of an ingroup and two outgroups. In Study 2, 42 subjects performed similar tasks for ingroup or outgroup, and evaluated likeable and unlikeable group members. Results showed, first, that overall group ratings account better for ingroup bias than do central tendencies of group distributions. In addition, likeable and unlikeable ingroup members were, respectively, upgraded and downgraded relative to their outgroup counterparts. Finally, whole ingroup ratings as well as judgements of likeable and unlikeable ingroup members proved more independent from variability and central tendency of underlying distributions than did similar outgroup judgements. Results are discussed in light of motivational and knowledge-based determinants of group judgements.  相似文献   
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