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951.
We conducted this study to determine the relationship between math preference and mastery for five middle school students with autism spectrum disorders. We randomly presented several math addition and subtraction problem formats to determine the students’ preferences. Results indicated that preference was idiosyncratic across students. In addition, preference was not related to mastery in some students. Results are discussed within a theoretical framework of matching law. Implications for practitioners are discussed.
Devender R. BandaEmail:
  相似文献   
952.
Exposure to an enriched environment (EE) has been shown to induce cortical plasticity. Considerable amount of research is focused on the effects of EE in the hippocampus; however, effects of EE on other brain regions and the mechanisms involved are not well known. To investigate this, we induced cortical plasticity by placing mice in an EE for one month and measured the effects of EE in the anterior cingulate cortex (ACC). Here, we show that EE enhanced the expression of the plasticity gene, egr-1, in the ACC of EE animals accompanied by enhanced cingulate long-term potentiation (LTP) and decreased cingulate long-term depression (LTD). The increased NMDA receptor NR2B/NR2A subunits current ratio is associated with the plasticity seen in the ACC while total protein levels remain unchanged. Furthermore, behavioral experiments show that these mice exposed to EE demonstrate enhanced responses to acute and long-term inflammation. Our findings suggest that exposure to EE alters physiological properties within the ACC which results in enhanced responses to inflammation.  相似文献   
953.
Imaging, electrophysiological studies, and lesion work have shown that the medial temporal lobe (MTL) is important for episodic memory; however, it is unclear whether different MTL regions support the spatial, temporal, and item elements of episodic memory. In this study we used fMRI to examine retrieval performance emphasizing different aspects of episodic memory in the context of a spatial navigation paradigm. Subjects played a taxi-driver game ("yellowcab"), in which they freely searched for passengers and delivered them to specific landmark stores. Subjects then underwent fMRI scanning as they retrieved landmarks, spatial, and temporal associations from their navigational experience in three separate runs. Consistent with previous findings on item memory, perirhinal cortex activated most strongly during landmark retrieval compared with spatial or temporal source information retrieval. Both hippocampus and parahippocampal cortex activated significantly during retrieval of landmarks, spatial associations, and temporal order. We found, however, a significant dissociation between hippocampal and parahippocampal cortex activations, with spatial retrieval leading to greater parahippocampal activation compared with hippocampus and temporal order retrieval leading to greater hippocampal activation compared with parahippocampal cortex. Our results, coupled with previous findings, demonstrate that the hippocampus and parahippocampal cortex are preferentially recruited during temporal order and spatial association retrieval--key components of episodic "source" memory.  相似文献   
954.
Context-induced drug craving and continuous drug use manifest the critical roles of specific memory episodes associated with the drug use experiences. Drug-induced conditioned place preference (CPP) in C57BL/6J mouse model, in this regard, is an appropriate behavioral paradigm to study such drug use-associated memories. Requirement of protein synthesis in various forms of long-term memory formation and storage has been phylogenetically demonstrated. This study was undertaken to study the requirement of protein synthesis in the learning and memory aspect of the conditioned place preference induced by cocaine and methamphetamine, two abused drugs of choice in local area. Since pCREB has been documented as a candidate substrate for mediating the drug-induced neuroadaptation, the pCREB level in hippocampus, nucleus accumbens, and prefrontal cortex was examined for its potential participation in the formation of CPP caused by these psychostimulants. We found that cocaine (2.5 and 5.0 mg/kg/dose)-induced CPP was abolished by the pretreatment of anisomycin (50 mg/kg/dose), a protein synthesis inhibitor, whereas methamphetamine (0.5 or 1.0 mg/kg/dose)-induced CPP was not affected by the anisomycin pretreatment. Likewise, cocaine-induced CPP was mitigated by another protein synthesis inhibitor, cycloheximide (15 mg/kg/injection) pretreatment, whereas methamphetamine-induced CPP remained intact by such pretreatment. Moreover, anisomycin treatment 2h after each drug-place pairing disrupted the cocaine-induced CPP, whereas the same treatment did not affect methamphetamine-induced CPP. An increase of accumbal pCREB level was found to associate with the learning phase of cocaine, but not with the learning phase of methamphetamine. We further found that intraaccumbal CREB antisense oligodeoxynucleotide infusion diminished cocaine-induced CPP, whereas did not affect the methamphetamine-induced CPP. Taken together, these data suggest that protein synthesis and accumbal CREB phosphorylation are essential for the learning and consolidation of the cocaine-induced CPP, whereas methamphetamine-induced CPP may be unrelated to the synthesis of new proteins.  相似文献   
955.
Two experiments examined the effects of majority and minority influence on attitude-consistent behavioral intentions. In the first experiment, when attitudes were changed via minority influence there was a greater likelihood to engage in an attitude-consistent behavioral intention than when attitudes were changed via majority influence. This suggests that minority influence leads to stronger attitudes (based on systematic processing) that are more predictive of behavioral intentions, while attitude change via majority influence is due to compliance through non-systematic processing. Further support for this interpretation comes from the finding that the amount of message-congruent elaboration mediated behavioral intention. When there was no attitude change, there was no impact on behavioral intention to engage in an attitude-consistent behavior. Experiment 2 explored the role of personal relevance of the topic and also included a real behavioral measure. When the topic was of low personal relevance, the same pattern was found as Experiment 1. When the topic was of high personal relevance, thus increasing the motivation to engage in systematic processing, attitudes changed by both a majority and minority source increased behavioral intention and actual behavior. The results are consistent with the view that both majorities and minorities can lead to different processes and consequences under different situations.  相似文献   
956.
The authors addressed the interactions between control of bimanual multijoint coordination tasks and posture. Participants (N = 6) performed 8 coordination patterns that differed in degree of complexity by using their bilateral elbows and wrists under 3 scaled motion speeds while standing on 2 force plates. Results indicated that producing complex bimanual multijoint coordinative tasks affected postural sway, thus resulting in an increase of sway activity. Behavioral as well as mechanical factors accounted for the increased disturbance in postural sway. Those findings suggest that performing complex coordination tasks disrupts postural control in normal young adults.  相似文献   
957.
The Hong Kong Government and the education sector encourage the whole population-from toddlers to senior citizens-to utilize information technology, and many do. Yet there are no studies exploring the patterns of adolescents using ICQ (I seek you) in Asian countries. This study was done in Hong Kong, which has the greatest number of ICQ users. A quantitative approach was adopted by administering self-constructed questionnaires to the students of one high school. One hundred and forty-seven adolescents volunteered to participate. The key findings of the study are (1) most of the adolescents have been using ICQ for 1-4 years; (2) most fit one of two patterns of use: either 2 or 3 days per week, or more than 5 days per week; (3) they spend less than 3 h per day on ICQ; (4) the main reasons for using ICQ are entertainment, relaxation, and socializing; and (5) parents are concerned about possible negative impacts on their children's academic performance because of using ICQ. Two main implications are drawn: proper use of ICQ can minimize parental distress and encourage adolescents to be less sedentary.  相似文献   
958.
959.
Today millions of players interact with one another in online games, especially massively multiplayer online role-playing games (MMORPGs). These games promote interaction among players by offering interdependency features, but to date few studies have asked what interdependency design factors of MMORPGs make them fun for players, produce experiences of flow, or enhance player performance. In this study, we focused on two game design features: task and reward interdependency. We conducted a controlled experiment that compared the interaction effects of low and high task-interdependency conditions and low and high reward-interdependency conditions on three dependent variables: fun, flow, and performance. We found that in a low task-interdependency condition, players had more fun, experienced higher levels of flow, and perceived better performance when a low reward-interdependency condition also obtained. In contrast, in a high task-interdependency condition, all of these measures were higher when a high reward-interdependency condition also obtained.  相似文献   
960.
Schizophrenia is a devastating mental illness and is characterized by hallucinations and delusions as well as social skills deficits. Generally, social skills training designed to help patients develop social skills includes role-playing, but this form of training has typical shortcomings, which are largely due to a trainer's difficulties to project emotion. Virtual reality (VR)-based techniques have the potential to solve these difficulties, because they provide a computer-generated but realistic three-dimensional world and humanlike avatars that can provide emotional stimuli. In this paper, we report on a method of implementing virtual environments (VEs) in order to train people with schizophrenia to develop conversational skills in specific situations, which could overcome the shortcomings of or complement conventional role-playing techniques. The paper reports the efficacy of the proposed approach in a preliminary clinical trial with 10 patients with schizophrenia.  相似文献   
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