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941.
Orlowski D Elfving B Müller HK Wegener G Bjarkam CR 《Stress (Amsterdam, Netherlands)》2012,15(5):514-523
The aim of this study was to investigate whether the previously reported effect of chronic restraint stress (CRS) on hippocampal neuron morphology and spine density is paralleled by a similar change in the expression levels of synaptic scaffolding proteins. Adult male Wistar rats were subjected either to CRS (6 h/day) for 21 days or to control conditions. The resulting brains were divided and one hemisphere was impregnated with Golgi-Cox before coronal sectioning and autometallographic development. Neurons from CA1, CA3b, CA3c, and dentate gyrus (DG) area were reconstructed and subjected to Sholl analysis and spine density estimation. The contralateral hippocampus was used for quantitative real-time polymerase chain reaction and protein analysis of genes associated with spine density and morphology (the synaptic scaffolding proteins: Spinophilin, Homer1-3, and Shank1-3). In the CA3c area, CRS decreased the number of apical dendrites and their total length, whereas CA1 and DG spine density were significantly increased. Analysis of the contralateral hippocampal homogenate displayed an increased gene expression of Spinophilin, Homer1, Shank1, and Shank2 and increased protein expression of Spinophilin and Homer1 in the CRS animals. In conclusion, CRS influences hippocampal neuroplasticity by modulation of dendrite branching pattern and spine density paralleled by increased expression levels of synaptic scaffolding proteins. 相似文献
942.
Navigation assistance: a trade-off between wayfinding support and configural learning support 总被引:1,自引:0,他引:1
Current GPS-based mobile navigation assistance systems support wayfinding, but they do not support learning about the spatial configuration of an environment. The present study examined effects of visual presentation modes for navigation assistance on wayfinding accuracy, route learning, and configural learning. Participants (high-school students) visited a university campus for the first time and took a predefined assisted tour. In Experiment 1 (n = 84, 42 females), a presentation mode showing wayfinding information from eye-level was contrasted with presentation modes showing wayfinding information included in views that provided comprehensive configural information. In Experiment 2 (n = 48, 24 females), wayfinding information was included in map fragments. A presentation mode which always showed north on top of the device was compared with a mode which rotated according to the orientation of the user. Wayfinding accuracy (deviations from the route), route learning, and configural learning (direction estimates, sketch maps) were assessed. Results indicated a trade-off between wayfinding and configural learning: Presentation modes providing comprehensive configural information supported the acquisition of configural knowledge at the cost of accurate wayfinding. The route presentation mode supported wayfinding at the cost of configural knowledge acquisition. Both presentation modes based on map fragments supported wayfinding. Individual differences in visual-spatial working memory capacity explained a considerable portion of the variance in wayfinding accuracy, route learning, and configural learning. It is concluded that learning about an unknown environment during assisted navigation is based on the integration of spatial information from multiple sources and can be supported by appropriate visualization. 相似文献
943.
Villarejo C Fernández-Aranda F Jiménez-Murcia S Peñas-Lledó E Granero R Penelo E Tinahones FJ Sancho C Vilarrasa N Montserrat-Gil de Bernabé M Casanueva FF Fernández-Real JM Frühbeck G De la Torre R Treasure J Botella C Menchón JM 《European eating disorders review : the journal of the Eating Disorders Association》2012,20(3):250-254
944.
Ulrich Kühnen Marieke C. van Egmond Frank Haber Stefanie Kuschel Amina ?zelsel Alexis L. Rossi Youlia Spivak 《Social Psychology of Education》2012,15(1):59-76
The current study investigated the value of Socratic classroom communication (e.g., critical debate and challenging each other
on content matters) among students from various cultures (clustered into Western Europeans, Eastern Europeans and Non-Europeans)
and from members of faculty at an international university in Germany. Students from Western cultures where Socratic communication
had been valued in the school systems reported a greater ease of engaging in the respective communication style than did Eastern
European and Non-European students. Furthermore, we assessed how strongly the faculty valued the respective kinds of behavior.
The results show that overall students underestimated the extent to which Socratic communication behavior was esteemed by
members of faculty. In addition, faculty members perceived themselves to be more explicit about their pedagogical principles
than they were perceived by students. Finally, the easier it was for students to show Socratic classroom communication, the
more academically satisfied they were and the better their grades. The results are discussed with regard to practical implications
and the internationalization of universities. 相似文献
945.
Cunillera T Fuentemilla L Periañez J Marco-Pallarès J Krämer UM Càmara E Münte TF Rodríguez-Fornells A 《Cognitive, affective & behavioral neuroscience》2012,12(1):16-33
In this study, we sought to dissociate event-related potentials (ERPs) and the oscillatory activity associated with signals
indicating feedback about performance (outcome-based behavioral adjustment) and the signals indicating the need to change
or maintain a task set (rule-based behavioral adjustment). With this purpose in mind, we noninvasively recorded electroencephalographic
signals, using a modified version of the Wisconsin card sorting task, in which feedback processing and task switching could
be studied separately. A similar late positive component was observed for the switch and correct feedback signals on the first
trials of a series, but feedback-related negativity was observed only for incorrect feedback. Moreover, whereas theta power
showed a significant increase after a switch cue and after the first positive feedback of a new series, a selective frontal
beta–gamma increase was observed exclusively in the first positive feedback (i.e., after the selection of the new rule). Importantly,
for the switch cue, beta–alpha activity was suppressed rather than increased. This clear dissociation between the cue and
feedback stimuli in task switching emphasizes the need to accurately study brain oscillatory activity to disentangle the role
of different cognitive control processes. 相似文献
946.
This study examined the lexical representations and psycholinguistic mechanisms underlying the production and recognition of novel words with two pronunciation variants in French. Participants first learned novel schwa words (e.g., /??nyk/), which varied in their alternating status (i.e., whether these words were learned with one or two variants) and, for alternating words, in the frequency of their variants. They were then tested in picture-naming (free or induced) and recognition memory tasks (i.e., deciding whether spoken items were learned during the experiment or not). Results for free naming show an influence of variant frequency on responses, more frequent variants being produced more often. Moreover, our data show an effect of the alternating status of the novel words on naming latencies, with longer latencies for alternating than for nonalternating novel words. These induced naming results suggest that both variants are stored as lexical entries and compete during the lexeme selection process. Results for recognition show an effect of variant frequency on reaction times and no effect of variant type (i.e., schwa versus reduced variant). Taken together, our findings suggest that participants both comprehend and produce novel French schwa words using two lexical representations, one for each variant. 相似文献
947.
948.
Michael Zehetleitner Dragan Rangelov Hermann J. Müller 《Attention, perception & psychophysics》2012,74(5):879-890
Search performance is sequence-dependent. A specific finding observed in compound-search tasks consists of an interaction between cross-trial sequences (repetition vs. change) of the target-defining (primary) and response-defining (secondary) features: The effect of a target change is greater when the response stays the same than when the response changes. The present study tested whether this interaction arises from processes involved in target search or from later processes in compound tasks. Uncertainty about the upcoming target location??that is, the search component of compound tasks??was removed in different experiments, either by the use of exogenous spatial precues or by presenting only one, central item. Despite having removed the search component, we observed a robust interaction between target (primary) and response (secondary) feature sequences. These results suggest that this interaction originates from a processing stage concerned with discriminating the response feature of a single (selected) item, rather than from a search-related stage. Furthermore, the results support our multiple-weighting-systems hypothesis, according to which sequence effects in visual search tasks do not stem from a single, unitary mechanism; rather, multiple stages of processing on any given trial can lead to separate memory traces, which in turn have effects on different stages of processing on the subsequent trial. 相似文献
949.
Schlittmeier SJ Weissgerber T Kerber S Fastl H Hellbrück J 《Attention, perception & psychophysics》2012,74(1):194-203
Background sounds, such as narration, music with prominent staccato passages, and office noise impair verbal short-term memory even when these sounds are irrelevant. This irrelevant sound effect (ISE) is evoked by so-called changing-state sounds that are characterized by a distinct temporal structure with varying successive auditory-perceptive tokens. However, because of the absence of an appropriate psychoacoustically based instrumental measure, the disturbing impact of a given speech or nonspeech sound could not be predicted until now, but necessitated behavioral testing. Our database for parametric modeling of the ISE included approximately 40 background sounds (e.g., speech, music, tone sequences, office noise, traffic noise) and corresponding performance data that was collected from 70 behavioral measurements of verbal short-term memory. The hearing sensation fluctuation strength was chosen to model the ISE and describes the percept of fluctuations when listening to slowly modulated sounds (f(mod) < 20?Hz). On the basis of the fluctuation strength of background sounds, the algorithm estimated behavioral performance data in 63 of 70 cases within the interquartile ranges. In particular, all real-world sounds were modeled adequately, whereas the algorithm overestimated the (non-)disturbance impact of synthetic steady-state sounds that were constituted by a repeated vowel or tone. Implications of the algorithm's strengths and prediction errors are discussed. 相似文献
950.
Dr. Hans-Jürgen Wirth 《International Forum of Psychoanalysis》2013,22(2):94-107
Abstract The existence of man is distinguished by its split state: man stands in the middle of life yet still has an awareness of his own death. He has to compensate whatever is missing in him naturally at the societal level, created as culture, and at the individual level through creativity. Rank investigated the human ‘creative drive’, the anthropological aspiration to express oneself in creative works, and to overcome the fear of death with its help. Freud admired poets and artists, whose achievements he could not psychoanalytically access, but he considered science superior to the harmless and naïve arts. There are two anthropological radicals: premature birth and the consciousness of death. Freud's massive fear of death made it difficult for him to acknowledge the problem of death appropriately. In Rank's concept, the development of human creativity contributes towards the fear of death being alleviated so that the knowledge of death can be integrated into life; creativity belongs to the fundamental opportunities of man that may enable him to find a way through neurosis. Failure is as much a part of life as is creativity: those who do not experience and accept life in its tragic dimension are denied creativity. Only a creative person who accepts his partial failure finds the strength to continue to be creative without his imperfect work leading to the ritual repetition of the same thing again and again, that is, getting stuck in recidivism. 相似文献