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971.
In this study, we investigated conditions and consequences of teacher popularity in primary schools. Teacher popularity is embedded in a theoretical framework that describes relationships between teacher competence, teaching quality, and student outcomes. In the empirical analyses, we used multilevel modeling to distinguish between individual students’ liking of the teacher and a teacher’s popularity as rated by the whole class (N?=?1070 students, 54 teachers). The classroom level composite of the extent to which students liked their teacher was a reliable indicator of teacher popularity. Teacher popularity was associated with teacher self-reports of self-efficacy and teaching enthusiasm and with external observers’ ratings of teaching quality. The grades students received were not related to the popularity ratings. In a longitudinal study, teacher popularity predicted students’ learning gains and interest development over and above the effects of teaching quality. These results suggest that teacher popularity can be a useful and informative indicator in research on students’ academic development and teacher effectiveness.  相似文献   
972.
When humans are about to manipulate an object, our brains use visual cues to recall an internal representation to predict its weight and scale the lifting force accordingly. Such a long-term force profile, formed through repeated experiences with similar objects, has been proposed to improve manipulative performance. Skillful object manipulation is crucial for many animals, particularly those that rely on tools for foraging. However, despite enduring interest in tool use in non-human animals, there has been very little investigation of their ability to form an expectation about an object’s weight. In this study, we tested whether wild chimpanzees use long-term force profiles to anticipate the weight of a nut-cracking hammer from its size. To this end, we conducted a field experiment presenting chimpanzees with natural wooden hammers and artificially hollowed, lighter hammers of the same size and external appearance. We used calibrated videos from camera traps to extract kinematic parameters of lifting movements. We found that, when lacking previous experience, chimpanzees lifted hollowed hammers with a higher acceleration than natural hammers (overshoot effect). After using a hammer to crack open one nut, chimpanzees tuned down the lifting acceleration for the hollowed hammers, but continued lifting natural hammers with the same acceleration. Our results show that chimpanzees anticipate the weight of an object using long-term force profiles and suggest that, similarly to humans, they use internal representations of weight to plan their lifting movements.  相似文献   
973.
Despite extant evidence of negative peer treatment of transgender adolescents and adults, little is known about how young children perceive transgender peers, particularly those who have socially transitioned or are living in line with their gender rather than sex at birth. Whereas children have been shown to be averse to gender nonconformity in peers, because many transgender children appear and behave in ways consistent with their expressed gender (but not their sex at birth), it is unclear how children evaluate these identities. In 2 studies, we investigated 5- to 10-year-old children’s (Ntotal = 113) preferences for transgender versus gender-“typical” peers who either shared their gender identity or did not. We also examined whether children categorized transgender peers by their sex or expressed gender, as it might inform their evaluations. Children preferred cisgender peers over transgender peers; however, they also liked peers of their own gender rather than the other gender (e.g., female participants preferred girls over boys), demonstrating that the oft-documented own-gender bias plays an important role even when children are reasoning about transgender peers. Children did not reliably categorize transgender peers by sex or gender; yet those who categorized transgender peers by their sex showed greater dislike of transgender peers. The current studies are the first to investigate cisgender children’s attitudes toward transgender children and suggest that perceptions of gender categorization and conformity play a role in children’s evaluations of transgender peers.  相似文献   
974.
The brain’s reward system undergoes major changes during adolescence, and an increased reactivity to social and nonsocial incentives has been described as a typical feature during this transitional period. Little is known whether there are sex differences in the brain’s responsiveness to social or monetary incentives during adolescence. The aim of this event-related potential (ERP) study was to compare the neurophysiological underpinnings of monetary and social incentive processing in adolescent boys versus girls. During ERP recording, 38 adolescents (21 females, 17 males; 13–18 years) completed an incentive delay task comprising (a) a reward versus punishment condition and (b) social versus monetary incentives. The stimulus-preceding negativity (SPN) was recorded during anticipation of reward and punishment, and the feedback P3 (fP3) along with the feedback-related negativity (FRN) after reward/punishment delivery. During anticipation of social punishment, adolescent boys compared with girls exhibited a reduced SPN. After delivery, male adolescents exhibited higher fP3 amplitudes to monetary compared with social incentives, whereas fP3 amplitudes in girls were comparable across incentive types. Moreover, whereas in boys fP3 responses were higher in rewards than in punishment trials, no such difference was evident in girls. The results indicate that adolescent boys show a reduced neural responsivity in the prospect of social punishment. Moreover, the findings imply that, once the incentive is obtained, adolescent boys attribute a relatively enhanced motivational significance to monetary incentives and show a relative hyposensitivity to punishment. The findings might contribute to our understanding of sex-specific vulnerabilities to problem behaviors related to incentive processing during adolescence.  相似文献   
975.
The analysis of timing in human movements requires a reference with which timing can be quantified. In reactive movements this reference is given by the stimulus. However, many movements do not respond to such an external event. In throwing, for instance, the hand opening for release has to be timed to an acceleration of the throwing arm. A common approach to analyzing release-timing variability is to choose a landmark in the movement that is supposed to have a fixed temporal relation to the release. Such distinct landmarks, however, are not always well definable. Therefore, the present article describes an alternative approach analyzing timing variability on the basis of the alignment of different trials relative to their kinematic shape, by shifting the trials in the time domain. The basic assumption behind this approach is that single throwing movements are one instance of an acquired movement template, and thus show a considerable similarity. In contrast, the location of the temporal moment of release varies from trial to trial, generating imprecision regarding the release timing. In trials synchronized with respect to the release, this variability can be assessed by shifting the kinematic profiles of the throwing movements in time such that they superimpose as closely as possible. As a result, the corresponding time shifts for all trials represent a measure of the release time deviations across trials, and the standard deviation of these deviations represents the timing variability. Aside from timing analyses in such movements as throwing, the approach can be applied to very different tasks with timing demands—for example, to neurophysiological signals.  相似文献   
976.
Background/Objective: Lower levels in well-being have been observed in individuals with Major Depression (MDD) and Social Phobia (SP), but well-planned direct comparisons with control individuals, not suffering from a mental disorder, are lacking. Furthermore, MDD is highly comorbid with anxiety disorders, and SP with depressive disorders. This study is among the first to examine differences in well-being in individuals with a clinical diagnosis of MDD or SP compared to individuals with no such diagnosis and to test differences in well-being within the combined diagnostic categories respective with and without anxiety-depressive comorbidity. Method: Participants were 119 individuals with a diagnosis of MDD, 47 SP and 118 controls. Results: Results revealed that overall well-being as well as emotional, psychological, and social well-being were lower in the MDD and SP group compared to the control group. Individuals with comorbidity reported lower well-being than individuals without comorbidity. Conclusions: These findings have clinical implications as presence of comorbidity may require a different therapeutic approach than with no comorbidity.  相似文献   
977.
Today, thanks to biomedical technologies advances, some persons with fertility issues can conceive. Transgender persons benefit also from these advances and can not only actualize their self-identified sexual identities but also experience parenthood. Based on clinical multidisciplinary seminars that gathered child psychiatrists and psychoanalysts interested in the fields of assisted reproduction technology (ART) and gender dysphoria, philosophers interested in bioethics, biologists interested in ART, and endocrinologists interested in pubertal suppression, we explore how new biotechnical advances, whether in gender transition or procreation, could create new ways to conceive a child possible. After reviewing the various medical/surgical techniques for physical gender transition and the current ART options, we discuss how these new ways for persons to self-actualize and to experience parenthood can not only improve the condition of transgender persons (and the human condition as a whole through greater equity) but also introduce some elements of change in the habitual patterns of thinking especially in France. Finally, we discuss the ethical issues that accompany the arrival of these children and provide creative solutions to help society handle, accept, and support the advances made in this area.  相似文献   
978.
Goodale and Milner's two visual system hypothesis is an influential model for the understanding of the primate visual system. Lesions of either the ventral (occipito‐temporal) or the dorsal (occipito‐parietal) stream produce distinct and dissociated syndromes in humans: visual agnosia is typical for ventral damage, whereas optic ataxia (OA) for dorsal damage. We studied the case of a 59‐year‐old left‐handed woman with a circumscribed lesion around the left posterior occipital sulcus, extending to the underlying white matter. Initially, she presented with a central visual field OA, which regressed to an OA to the right visual hemifield during the 3 months observation period. In addition, tachistoscopic experiments showed visual hemiagnosia to the right visual hemifield. In line with the findings of the neuropsychological experiments, the analysis of the structural MR data by means of a trackwise hodologic probabilistic approach revealed damage to the left superior longitudinal fasciculus and to the left inferior longitudinal fasciculus, indicating an impairment of both the dorsal and the ventral stream. The combination of OA and visual hemiagnosia in the same patient has never been previously described. The present case study thus provides further insights for the understanding of visual processing.  相似文献   
979.
When two overlapping tasks are processed, they hit a bottleneck at a central processing stage that prevents simultaneous processing of the two tasks. Thus far, however, the factors determining the processing order of the tasks at the bottleneck are unknown. The present study was designed to (re)investigate whether the arrival times of the two tasks at the central bottleneck are a key determinant of the processing order (cf. Sigman & Dehaene, 2006). To this end, we implemented a visual–auditory dual task with a random stimulus order, in which we manipulated arrival time by prolonging the initial, perceptual processing stage (stimulus analysis) of the visual task and compared the effects of this manipulation with those of one impacting the central bottleneck stage of the visual task. Additionally, we implemented two instruction conditions: Participants were told to respond either in the order of stimulus presentation or in the order they preferred. The manipulation of the visual perception stage led to an increase in task response reversals (i.e., the response order was different from the order of stimulus presentation), whereas there was no such increase when the bottleneck stage was manipulated. This pattern provides conclusive evidence that the processing order at the bottleneck is (at least in part) determined by the arrival times of the tasks at that point. Reaction time differences between the two instruction conditions indicated that additional control processes are engaged in determining task processing order when the participants are expressly told to respond in the order of stimulus presentation.  相似文献   
980.

Shielding visual search against interference from salient distractors becomes more efficient over time for display regions where distractors appear more frequently, rather than only rarely Goschy, Bakos, Müller, & Zehetleitner (Frontiers in Psychology 5: 1195, 2014). We hypothesized that the locus of this learned distractor probability-cueing effect depends on the dimensional relationship of the to-be-inhibited distractor relative to the to-be-attended target. If the distractor and target are defined in different visual dimensions (e.g., a color-defined distractor and orientation-defined target, as in Goschy et al. (Frontiers in Psychology 5: 1195, 2014), distractors may be efficiently suppressed by down-weighting the feature contrast signals in the distractor-defining dimension Zehetleitner, Goschy, & Müller (Journal of Experimental Psychology: Human Perception and Performance 38: 941–957, 2012), with stronger down-weighting being applied to the frequent- than to the rare-distractor region. However, given dimensionally coupled feature contrast signal weighting (cf. Müller J, Heller & Ziegler (Perception & Psychophysics 57:1–17, 1995), this dimension-(down-)weighting strategy would not be effective when the target and the distractors are defined within the same dimension. In this case, suppression may operate differently: by inhibiting the entire frequent-distractor region on the search-guiding master saliency map. The downside of inhibition at this level is that, although it reduces distractor interference in the inhibited (frequent-distractor) region, it also impairs target processing in that region—even when no distractor is actually present in the display. This predicted qualitative difference between same- and different-dimension distractors was confirmed in the present study (with 184 participants), thus furthering our understanding of the functional architecture of search guidance, especially regarding the mechanisms involved in shielding search from the interference of distractors that consistently occur in certain display regions.

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