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141.
Several studies have shown that a phonological deficit is the origin of developmental dyslexia, because dyslexics have important difficulties in mapping orthographic to phonological codes. However, visual criteria are still used for the diagnosis of dyslexia and to develop methods of intervention. This study attempts to determine whether there are visual problems in dyslexic children. To this aim, dyslexic children and children without reading difficulties, matched by chronological age, participated in two experiments. One study was based on the Reversal test and the other was a visual decision task in which participants had to decide whether two letters were the same or different. There were 40 pairs of letters, to measure reaction times and mistakes. The results showed that dyslexics had similar performance to controls in the detection of different visual stimuli. Developmental dyslexics do not appear to have visual perceptual problems, but a particular difficulty to retrieve the phonological code of graphemes.  相似文献   
142.
Outsourcing of jobs to contract workers who work alongside a client's employees has changed the human resource landscape of many organizations. In this study we examine how a contract worker's perceived employment status similarity to the client's own standard employees influences his/her affective commitment to both the client and the employer and ultimately intent to quit the employer. Using a sample of 623 contract workers, we found strong support for our hypotheses. In particular, findings indicate an important role for perceived employment status at the client organization in driving contract worker's attitudes and that contract workers consider both the client and the employer when making decisions to leave the employer. Implications for managing contractor relationships are discussed.  相似文献   
143.
Much has been written about the situations most often feared by persons with social phobia, and several self-report measures are frequently used to assess such feared situations. However, it is not clear whether the situations feared by persons with social phobia form unidimensional or multidimensional factors. If these situations are multidimensional, reliance on a total score of feared situations would not reflect important differences between those dimensions. This research examined the multidimensional nature and multicultural validity of a newly developed instrument (the Social Anxiety Questionnaire for Adults [SAQ-A]) in two studies with a total of 539 patients diagnosed with social phobia and 15,753 nonpatients from 20 different countries. The structure (five clear and solid factors) and psychometric properties of the final instrument (the SAQ-A30) support the multidimensional nature of social anxiety and provide a new perspective in the assessment of social phobia.  相似文献   
144.
People perform leisure activities (LA) every day; pursuits that entail applying cognitive, physical and social abilities. As in old age, doing LA during early and middle adulthood is related to a reduced risk of dementias, probably by generating a cognitive reserve. As it is possible that a relation between doing LA and working memory (WM) efficiency exists in young adults, we assessed whether the diversity and frequency of LA are related to WM efficiency in this population. Ninety-three healthy young subjects solved the n-back task at two levels of difficulty (2, 3), and answered an LA questionnaire on the activities in which they had participated in the month prior to the experiment. Subjects were classified separately on their scores for (1) diversity (high/low) and (2) frequency (high/low) in order to test the relation between each variable and WM efficiency. Though no differences were found, a subsequent analysis of the average of diversity and frequency ratios of LA performance taken together-the diversity/frequency index-showed that low diversity plus low frequency was significantly associated with reduced WM efficiency at this age; results that suggest that frequent participation in diverse LA during youth is related to WM efficiency.  相似文献   
145.
Sleep deprivation reduces vigilance or arousal levels, affecting the efficiency of certain cognitive functions such as learning and memory. Here we assessed whether the differential outcomes procedure (DOP), a learning procedure that has proved useful to ameliorate episodic memory deficits, can also improve memory performance in sleep-deprived participants. Photographs were presented as sample faces. A probe face was then presented for recognition after either short or long delays. In the differential outcomes condition a unique reinforcer followed correct responses. In the non-differential outcomes condition reinforcers were provided in a random manner. The results indicated that the DOP prevented the recognition memory to decrement during the long delay in the control group, replicating previous findings. The sleep-deprived group showed DOP benefits mainly with the short delay, when working memory could be affected by low arousal. These findings confirm that the DOP can overcome impaired recognition memory due to sleep deprivation conditions.  相似文献   
146.
J Gervain  R Guevara Erra 《Cognition》2012,125(2):263-287
Does statistical learning (Saffran, Aslin, &; Newport, 1996) offer a universal segmentation strategy for young language learners? Previous studies on large corpora of English and structurally similar languages have shown that statistical segmentation can be an effective strategy. However, many of the world’s languages have richer morphological systems, with sometimes several affixes attached to a stem (e.g. Hungarian: iskoláinkban: iskolá-i-nk-ban school.pl.poss1pl.inessive ‘in our schools’). In these languages, word boundaries and morpheme boundaries do not coincide. Does the internal structure of words affect segmentation? What word forms does segmentation yield in morphologically rich languages: complex word forms or separate stems and affixes? The present paper answers these questions by exploring different segmentation algorithms in infant-directed speech corpora from two typologically and structurally different languages, Hungarian and Italian. The results suggest that the morphological and syntactic type of a language has an impact on statistical segmentation, with different strategies working best in different languages. Specifically, the direction of segmentation seems to be sensitive to the affixation order of a language. Thus, backward probabilities are more effective in Hungarian, a heavily suffixing language, whereas forward probabilities are more informative in Italian, which has fewer suffixes and a large number of phrase-initial function words. The consequences of these findings for potential segmentation and word learning strategies are discussed.  相似文献   
147.
148.
The influence of parents and teachers in the decisions made by adolescents regarding study options has not been widely documented in Spain. The main aim of this qualitative study consisted of analyzing the opinions of parents and secondary school teachers about their role in the different academic and professional choices boys and girls make. Seven focus groups (4 with 27 parents and 3 with 22 secondary school teachers) from 5 schools located in urban and rural areas of Catalonia (Spain) were carried out in order to explore how both groups perceive Information and Communication Technology (ICT) professionals, gender differences in study options and their own role in adolescents’ choice of study options. Our findings show that parents and teachers hold stereotypes about ICTs and consider that gender does not condition adolescents’ study choices. Both groups saw themselves as playing a secondary role in adolescents’ academic and professional choices. Some gender differences among parents and teachers emerged regarding their perception of the ICT professionals and their own role and of others in shaping adolescents’ study choices.?The findings and their practical implications are discussed.  相似文献   
149.
Presently, little is known about the effect of curved backgrounds against which the target stimulus is presented on precision in stereoacuity. The experiment analyzed the influence of stimulus orientation and 3D background configuration on stereoscopic vision. Participants were instructed to perform 3D visual alignment tasks on a modified version of the Howard-Dolman apparatus, whereupon precision in depth perception for different curved backgrounds (flat, black, concave, and convex) was evaluated. In addition, the influence of stimulus orientation (0 degrees, 45 degrees, and 90 degrees) on precision was examined. The findings revealed an underestimation in the perceived depth in all background configurations, indicating highest and lowest precision outcomes for convex and concave backgrounds, respectively. In addition, a significant interaction of background and orientation was found. It was concluded that, in a real environment, background local depth cues are integrated with target stimuli to contribute to depth perception.  相似文献   
150.
Mixed martial arts (MMA) have become a fast-growing worldwide expansion of martial arts competition, requiring high level of skill, physical conditioning, and strategy, and involving a synthesis of combat while standing or on the ground. This study quantified the effort-pause ratio (EP), and classified effort segments of stand-up or groundwork development to identify the number of actions performed per round in MMA matches. 52 MMA athletes participated in the study (M age = 24 yr., SD = 5; average experience in MMA = 5 yr., SD = 3). A one-way analysis of variance with repeated measurements was conducted to compare the type of action across the rounds. A chi-squared test was applied across the percentages to compare proportions of different events. Only one significant difference (p < .05) was observed among rounds: time in groundwork of low intensity was longer in the second compared to the third round. When the interval between rounds was not considered, the EP ratio (between high-intensity effort to low-intensity effort plus pauses) was 1:2 to 1:4. This ratio is between ratios typical for judo, wrestling, karate, and taekwondo and reflects the combination of ground and standup techniques. Most of the matches ended in the third round, involving high-intensity actions, predominantly executed during groundwork combat.  相似文献   
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