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901.
Pedro-Viejo AB 《Psicothema》2008,20(4):551-556
The adoption waiting period is a powerful stressor that can affect the well-being and configuration of future family life. Adoption research and practice have not paid enough attention to this phase. The principal aim of this study is to address prospective adoptive parents' experience of and coping with this period. For this purpose, 63 families answered a feelings scale, a coping resources scale and a needs questionnaire, all elaborated for the study. Results show that a shorter length of waiting time, using cognitive and learning coping strategies and associative participation were related to a better general experience of adoption whereas process-centred strategies were related to a worse experience of adoption. Families would like to see more speed in the process, more warmth and humanity in their relation with institutions and better information about their expedients. We conclude by proposing some activities and services during the waiting period that could be useful for post adoption.  相似文献   
902.
In this study, peer relationships of minors in residential care in a school context are analysed, both from the perspective of the peers and the teachers. Using a sociometric test and an evaluation protocol for teachers in 50 classrooms, a sample of 60 minors in care is compared to a normative sample of 843 minors. The results show that minors in residential care have a higher rate of rejection by their classmates in academic activities, but not for leisure ones. Furthermore, in comparison with the normative sample, they are more frequently described with negative adjectives. There is a high level of agreement between the peer evaluation and that of the teachers in the most visible aspects in the classroom. The implications of these results for the improvement of the adjustment of this group are discussed.  相似文献   
903.
Taking into account the studies about the measure of sensitivity in magnitude estimation tasks, we analyze the three most common measures used in this topic: Pearson's product-moment correlation between the logarithm of the stimulus and the logarithm of the response (R), the exponent of Stevens' power function (K), and the measure "M" proposed by Garriga-Trillo. Using a sample of participants greater than usual in psychophysical studies (180 participants), we designed an experiment with two sets of stimuli with different stimulus ranges. In each of these sets, we used two kinds of stimuli (line segments and squares). Our conclusions were: (1) we rejected the use of K as a sensitivity measure because the results provided by this index were the opposite of those expected when we compared the two stimulus ranges. (2) We also rejected the use of M because this measure is a linear transformation of Kendall's coefficient of concordance. (3) Lastly, we suggest the mathematical transformation proposed by Fisher to achieve a normal distribution, and recommend this transformation as the best sensitivity measure.  相似文献   
904.
Koning A  de Weert CM  van Lier R 《Perception》2008,37(9):1434-1442
We investigated the role of transparency, perceptual grouping, and presentation time on perceived lightness. Both transparency and perceptual grouping have been found to result in assimilation effects, but only for ambiguous stimulus displays and with specific attentional instructions. By varying the presentation times of displays with two partly overlapping transparent E-shaped objects, we measured assimilation in unambiguous stimulus displays and without specific attentional instructions. The task was to judge which of two simultaneously presented E-shaped objects was darker. With unrestrained presentation times, if a transparency interpretation was possible, assimilation was not found. Inhibiting a transparency interpretation by occluding the local junctions between the two E-shaped objects, did lead to assimilation. With short presentation times, if a transparency interpretation was possible, assimilation was now also found. Thus, we conclude that, although transparency appears to enhance assimilation, with unambiguous stimulus displays and without specific attentional instructions, perceptual grouping is more important for assimilation to occur.  相似文献   
905.
We compare two different styles of Higher-Order Unification (HOU): the classical HOU algorithm of Huet for the simply typed λ-calculus and HOU based on the λσ-calculus of explicit substitutions. For doing so, first, the original Huet algorithm for the simply typed λ-calculus with names is adapted to the language of the λ-calculus in de Bruijn's notation, since this is the notation used by the λσ-calculus. Afterwards, we introduce a new structural notation called unification tree, which eases the presentation of the subgoals generated by Huet's algorithm and its behaviour. The unification tree notation will be important for the comparison between Huet's algorithm and unification in the λσ-calculus whose derivations are presented into a structure called derivation tree. We prove that there exists an important structural correspondence between Huet's HOU and the λσ-HOU method: for each (sub-)problem in the unification tree there exists a counterpart in the derivation tree. This allows us to conclude that the λσ-HOU is a generalization of Huet's algorithm and that solutions computed by the latter are always computed by the former method.  相似文献   
906.
There is no agreement on how nanoethics should proceed. In this article I focus on approaches for discerning ethical issues in nanotechnology, which is as of yet one of the most difficult and urging tasks for nanoethics. I discuss and criticize two existing approaches for discerning ethical issues in nanotechnology and propose a network approach as alternative. I discuss debates in nanoethics about the desirable role of ethics in nanotechnological development and about the newness of ethical issues in nanotechnology. On basis of a critical analysis of both debates, I formulate a number of desiderata for a method for discerning ethical issues in nanotechnology and argue that the network approach that my colleagues and I have developed for ethical issues in research and development networks is also appropriate in nanotechnology.
Ibo van de PoelEmail:
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907.
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909.
Six studies examined how power affects responses to situational affordances. Participants were assigned to a powerful or a powerless condition and were exposed to various situations that afford different classes of behavior. Study 1 examined behavior intentions for weekdays and weekends. Studies 2 and 3 focused on responses to imaginary social and work situations. Study 4 examined planned behavior for winter and summer days. Finally, Studies 5 and 6 examined behavior and attention in the presence of situation-relevant and irrelevant information. Consistently across these studies, powerful individuals acted more in situation-consistent ways, and less in situation-inconsistent ways, compared with powerless individuals. These findings are interpreted as a result of the greater tendency for powerful individuals to process information selectively in line with the primary factors that drive cognition, such as affordances. One consequence of these findings is that powerful individuals change behavior across situations more than powerless individuals.  相似文献   
910.
ABSTRACT— When the perceptual system uses color to facilitate object recognition, it must solve the color-constancy problem: The light an object reflects to an observer's eyes confounds properties of the source of the illumination with the surface reflectance of the object. Information from the visual scene ( bottom-up information) is insufficient to solve this problem. We show that observers use world knowledge about objects and their prototypical colors as a source of top-down information to improve color constancy. Specifically, observers use world knowledge to recalibrate their color categories. Our results also suggest that similar effects previously observed in language perception are the consequence of a general perceptual process.  相似文献   
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