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881.
The purpose of this study was to manipulate psychological stress and anxiety to investigate effects on ensuing perceptual-motor learning. Thirty-six participants attended two experimental sessions separated by 24 h. In the first session, participants were randomized to either a mental arithmetic task known to increase stress and anxiety levels or a control condition and subsequently completed training on a speeded precision pinch task. Learning of the pinch task was assessed at the second session. Those exposed to the high stress-anxiety mental arithmetic task prior to training reported elevated levels of both stress and anxiety and demonstrated shorter movement times and improved retention of movement accuracy and movement variability. Response execution processes appear to benefit from elevated states of stress and anxiety immediately prior to training even when elicited by an unrelated task.  相似文献   
882.
883.
The novel coronavirus disease (COVID-19) is highly contagious. More than 247 million cases have been confirmed by the end of October 2021. Seeking help earlier may slow the spread of COVID-19 because it may help in early detection of infected cases, and it facilitate tracing those who were with close contact with infected cases. The purpose of this study is to identify participants’ intentions toward COVID-19 seeking help and the factors affecting their decision. This is a cross-sectional study. An online survey using Google Forms was used for data collection. Hierarchical multiple regression analysis was used to explain intentions to seek help for COVID-19. The concepts included in the Theory of Planned Behavior and COVID-19 knowledge were used as predictors. The sample included 780 participants, with an average age of 28.60±9.86 years old. Most of the sample were female (67.4%) and having a bachelor’s degree (72.7%). Participants showed high level of knowledge regarding COVID-19, 73% of the sample had a total knowledge score equal to or higher than 85%. Also, participants had high positive attitudes and high intentions to seek help for COVID-19. The four predictors: Attitudes towards COVID-19, subjective norm, perceived behavioral control, and COVID-19 knowledge significantly explained intentions to seek help. Participants had high intentions to seek help for COVID-19, which was related to having positive attitudes toward seeking help, high social approval, high perceived controllability, and high COVID-19 knowledge levels. Regular awareness campaigns during early stages of pandemics should be performed to improve attitudes and knowledge level, which may improve prevention measures, and promote help seeking behaviors. Consequently, this may facilitate early detection of cases, and slow the spread of pandemics.  相似文献   
884.
Multicriteria decision analysis (MCDA) methods have been recently applied in many environmental problems. Major aims have been to structure and to analyse multifaceted and complex problems, to compare incommensurable impacts and to clarify the preference order of alternatives. Most MCDA tools concentrate on aiding the process of choice among alternatives. The choice usually occurs at the end of the decision‐making process, but MCDA tools can also assist earlier in the process. In this article, we present a new MCDA‐based method in order to create watercourse regulation alternatives, which meet the objectives of stakeholders. The method is comprised of three elements: (1) framework for the planning and learning process partly based on the Image Theory, (2) analysis and evaluation of ecological, social and economic impacts of regulation, and (3) visual interactive Excel implementation of value‐tree analysis (REGAIM‐model). We show how the method was applied in a complex watercourse regulation development project in Finland. Altogether 36 face‐to‐face computer‐aided interviews were undertaken with the REGAIM model with representatives of different stakeholder groups. We present the main results of the interviews and discuss how these interviews supported generation of new watercourse regulation alternatives. We also describe the advantages of the new approach in the participatory watercourse management, and discuss the applicability of Image Theory in the watercourse regulation context. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
885.
曾国藩易学精蕴,尤以其读《易》风格显著,它贯融于读《易》致思和读《易》致用之中。究其至要有八个方面以读《易》为正业,朗诵《周易》得义生情,读幕僚《易》作品、与其幕友切磋探《易》.切已读《易》有点评,读《易》把握是心经,读《易》有悟感人生,人文境之美,占卦。由此可以看出,曾国藩其人其事其思想,与《周易》甚有渊源。  相似文献   
886.
The paper provides a framework for representing belief-contravening hypotheses in games of perfect information. The resulting t-extended information structures are used to encode the notion that a player has the disposition to behave rationally at a node. We show that there are models where the condition of all players possessing this disposition at all nodes (under their control) is both a necessary and a sufficient for them to play the backward induction solution in centipede games. To obtain this result, we do not need to assume that rationality is commonly known (as is done in [Aumann (1995)]) or commonly hypothesized by the players (as done in [Samet (1996)]). The proposed model is compared with the account of hypothetical knowledge presented by Samet in [Samet (1996)] and with other possible strategies for extending information structures with conditional propositions. This research was funded by the National Science Foundation: “Game-Theoretic Foundation for Multi-Agent Systems”, IIS 9734923. Special Issue Formal Epistemology II. Edited by Branden Fitelson  相似文献   
887.
The current study provides the first published evidence that the parasympathetic component of the autonomic nervous system differentiates the response profiles between individuals diagnosed with borderline personality disorder (BPD) and controls. Respiratory sinus arrhythmia (RSA), a non-invasive marker of the influence of the myelinated vagal fibers on the heart, and heart period were collected during the presentation of film clips of varying emotional content. The BPD and control groups had similar initial levels of RSA and heart period. However, during the experiment the groups exhibited contrasting trajectories, with the BPD group decreasing RSA and heart period and the control group increasing RSA and heart period. By the end of the experiment, the groups differ significantly on both RSA and heart period. The correlation between the changes in RSA and heart period was significant only for the control group, suggesting that vagal mechanisms mediated the heart period responses only in the control group. The findings were consistent with the Polyvagal Theory [Porges, S. W. (1995). Orienting in a defensive world: Mammalian modifications of our evolutionary heritage: A Polyvagal Theory. Psychophysiology, 32, 301-318; Porges, S. W. (2001). The Polyvagal Theory: Phylogenetic substrates of a social nervous system. International Journal of Psychophysiology, 42, 123-146; Porges, S. W. (2003). Social engagement and attachment: A phylogenetic perspective. Annals of the New York Academy of Sciences, 1008, 31-47.], illustrating different adaptive shifts in autonomic state throughout the course of the experiment. The BPD group ended in a physiological state that supports the mobilization behaviors of fight and flight, while the control group ended in a physiological state that supports social engagement behaviors. These finding are consistent with other published studies demonstrating atypical vagal regulation of the heart with other psychiatric disorders.  相似文献   
888.
Modularity in the human brain remains a controversial issue, with disagreement over the nature of the modules that exist, and why, when, and how they emerge. It is a natural assumption that modularity offers some form of computational advantage, and hence evolution by natural selection has translated those advantages into the kind of modular neural structures familiar to cognitive scientists. However, simulations of the evolution of simplified neural systems have shown that, in many cases, it is actually non-modular architectures that are most efficient. In this paper, the relevant issues are discussed and a series of simulations are presented that reveal crucial dependencies on the details of the learning algorithms and tasks that are being modelled, and the importance of taking into account known physical brain constraints, such as the degree of neural connectivity. A pattern is established which provides one explanation of why modularity should emerge reliably across a range of neural processing tasks.  相似文献   
889.
The past and current states of research on social comparison are reviewed with regard to a series of major theoretical developments that have occurred in the past 5 decades. These are, in chronological order: (1) classic social comparison theory, (2) fear-affiliation theory, (3) downward comparison theory, (4) social comparison as social cognition, and (5) individual differences in social comparison. In addition, we discuss a number of expansions of research on social comparison as they are currently occurring, and we outline what we see as likely and desirable future directions, including an expansion of areas, methods, and conceptualizations, as well as a stronger focus on cognitive, neuroscientific, and evolutionary aspects of social comparison.  相似文献   
890.
Two experiments investigated preschoolers’ understanding of the relation between pretending and intentional action. In Experiment 1, both 3- and 4-year olds recognized that characters whose actions were intended as pretense were pretending. However, children also judged that characters whose actions gave them the appearance of an entity unintentionally were pretending to be that entity. In Experiment 2, 3-year olds reliably chose a character whose pretense actions were intentional as pretending over a character whose actions were guided by another intention. These data suggest that preschoolers have some understanding of the role of intentional action in pretense.  相似文献   
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