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A closer look at unicellular organisms and their behavior as autonomous and social beings sheds new light on the nature of cognition. This allows, at the same time, a search for minimal conditions that help to identify the yet unknown appearance of cognition during evolution. Positive results might also serve as principles for the construction of intelligent artefacts as striven for in artificial intelligence and cognitive robotics research. Analyzing the abilities of prokaryotes and unicellular eukaryotes and comparing them to the abilities of "higher" organisms, we conclude that common definitions of cognition are not specific enough. The attempt to define cognition by focusing on the coupling between stimulus and response and asserting that (to have cognition) it has to be indirect and modifiable fails, simply because in all organisms every reaction to a stimulus is indirect and modifiable. A definition of cognition based on such a distinction cannot hold unless one is willing to ascribe cognitive capacities also to Escherichia coli bacteria, for instance. Viewing cognition as the sum of abilities necessary for coping with a complex physical and social environment is also highly questionable, i.e. unspecific. We show that functions comparable to the cognitive functions "perception" and "memory" in higher organisms can well be identified in unicellular beings. The "architecture" of the bacterial (prokaryotic) sensorimotor apparatus is also in some structures, but particularly at the functional level, comparable with that of higher organisms and should be, as a consequence, indicative of cognition. Furthermore, we discuss other, somewhat more delimitable, phenomena like detection of identity, counting, adaptation, habituation and learning in ethological categories and compare them to findings from the microorganismic world. In this context, we argue that so-called "true learning" and the appearance of nervous systems are not break-points in the evolution of cognition. The presence of nervous systems means only a huge amplification of the recognition power of individual organisms. The molecular net that realizes the regulation and transduction of signals in unicellular beings is comparable to the processes within a neural net, and a population of unicellular organisms can be viewed as an individual, multicellular net with amplified recognition power. Finally, we show that sophisticated forms of cooperation and competition developed also in populations of unicellular organisms. This seems not to be true for the phenomena imagination (rehearsal) and introspection, also to be seen as stemming from social problem-solving needs. As for these aspects, further research is needed, however, to put them on firm scientific grounds. Zusammenfassung. Eine genaue Betrachtung einzelliger Lebewesen und ihres Verhaltens als autonome und soziale Wesen wirft neues Licht auf die Natur von Kognition. Das erlaubt gleichzeitig eine Suche nach minimalen Bedingungen, die bei der Bestimmung des Erscheinens von Kognition in der Evolution helfen. Positive Ergebnisse könnten auch als Prinzipien für die Konstruktion intelligenter Artefakte dienen, wie sie in der Künstlichen Intelligenz und der kognitiven Robotikforschung angestrebt werden. Ein Vergleich der Fähigkeiten von Einzellern mit denen von "höheren" Organismen führt uns zu dem Schluß, daß gängige Definitionen von Kognition nicht spezifisch genug sind. Der Versuch, Kognition über die Indirektheit und Modifizierbarkeit der Kopplung zwischen Reiz und Reaktion zu definieren, scheitert, weil in allen Organismen Reiz-Reaktionsverbindungen indirekt und modifizierbar sind. Eine solche Definition ist nicht haltbar, es sei denn, man ist bereit, z.B. auch Escherichia coli-Bakterien kognitive Eigenschaften zuzubilligen. Die Definition von Kognition als Summe der Eigenschaften, die notwendig sind, um in einer komplexen physikalischen und sozialen Umgebung zu bestehen, ist ebenfalls hinterfragbar und unspezifisch. Wir zeigen, daß Leistungen, die mit den Kognitionsleistungen "Wahrnehmung" und "Gedächtnis" in höheren Organismen vergleichbar sind, in Einzellern nachweisbar sind. Die sensomotorische Komplexität von Einzellern ist auch in vieler Hinsicht strukturell, vor allem aber funktionell vergleichbar mit derjenigen höherer Organismen und kann deshalb als ein Hinweis auf Kognition gewertet werden. Darüber hinaus diskutieren wir andere, abgrenzbare Phänomene, wie Erfassung von Identität, Zählen, Adaptation, Habituation und Lernen, aus der Sicht der Verhaltensforschung und vergleichen sie mit Befunden aus der Welt der Mikroorganismen. In diesem Zusammenhang bestreiten wir, daß sogenanntes "echtes Lernen" und das Erscheinen von Nervensystemen Bruchstellen in der Evolution von Kognition sind. Die Anwesenheit von Nervensystemen bedeutet nur den Übergang von Systemen mit einem relativ begrenzten (Erkennungs-) Potential zu solchen mit einem riesigen Potential. Das molekulare Netz, das die Regulation und Transduktion von Signalen in Einzellern realisiert, ist vergleichbar mit den Prozessen innerhalb eines Nervennetzes. Eine Population von einzelligen Organismen kann als individuelles, multizelluläres Netz mit erhöhtem Erkennungspotential angesehen werden. Schließlich zeigen wir, daß raffinierte Formen von Kooperations- und Konkurrenzverhalten auch in Einzellerpopulationen vorhanden sind. Eine ähnliche Aussage scheint nicht für Phänomene wie Imagination (Probehandeln) und Introspektion möglich zu sein, die auch im Zusammenhang mit der Bewältigung sozialer Probleme zu sehen sind. Eine genaue naturwissenschaftliche Erfassung solcher Aspekte, die erst einen Vergleich zwischen Mehrzellern und Einzellern erlauben würde, ist allerdings noch zu leisten. 相似文献
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Joseph Sandler 《Psychometrika》1952,17(2):223-229
A technique is outlined which may facilitate the rotation of factor axes to a meaningful position. It is based on certain relationships between the results of test and person factor analysis, and consists essentially of supplementing the test factor space with tests which are thetest-equivalents of persons or groups of persons. These persons may be, for instance, well-known types in the domain being investigated, or even freaks. The ways in which these persons may be selected and used to determine the final rotated position of the factor axes is discussed. 相似文献
127.
The factor analysis of repeated measures psychiatric data presents interesting challenges for researchers in terms of identifying the latent structure of an assessment instrument. Specifically, repeated measures contain both within and between individual sources of variance. Although a number of techniques exist for separating out these 2 sources of variance, all are problematic. Recently, researchers have proposed that exploratory multilevel factor analysis (MFA) be used to appropriately analyze the latent structure of repeated measures data. The chief objective of this report is to provide a didactic step-by-step guide on how MFA may be applied to psychiatric data. In the discussion, we describe difficulties associated with MFA and consider challenges in factor analyzing life event appraisals in psychiatric samples. 相似文献
128.
Hojat M Mangione S Nasca TJ Gonnella JS Magee M 《The Journal of social psychology》2005,145(6):663-672
The authors designed the present study to examine the association between individuals' scores on the Jefferson Scale of Physician Empathy (JSPE; M. Hojat, J. S. Gonnella, S. Mangione, T. J. Nasca, & M. Magee, 2003; M. Hojat, J. S. Gonnella, T. J. Nasca, S. Mangione, M. Vergare, & M. Magee, 2002; M. Hojat, S. Mangione, T. J. Nasca, M. J. M. Cohen, J. S. Gonnella, J. B. Erdmann, J. J. Veloski, & M. Magee, 2001), a self-report empathy scale, during medical school and ratings of their empathic behavior made by directors of their residency training programs 3 years later. Participants were 106 physicians. The authors examined the relationships between scores on the JSPE (with 20 Likert-type items) at the beginning of the students' 3rd year of medical school and ratings of their empathic behavior made by directors of their residency training programs. Top scorers on the JSPE in medical school, compared to Bottom scorers, obtained a significantly higher average rating of empathic behavior in residency 3 years later (p < .05, effect size = 0.50). The findings support the long-term predictive validity of the self-report empathy scale, JSPE, despite different methods of evaluations (self-report and supervisors' ratings) and despite a time interval between evaluations (3 years). Because empathy is relevant to prosocial and helping behavior, it is important for investigators to further enhance our understanding of its correlates and outcomes among health professionals. 相似文献
129.
Hattiangadi N Pillion JP Slomine B Christensen J Trovato MK Speedie LJ 《Brain and language》2005,92(1):12-25
We present a case that is unusual in many respects from other documented incidences of auditory agnosia, including the mechanism of injury, age of the individual, and location of neurological insult. The clinical presentation is one of disturbance in the perception of spoken language, music, pitch, emotional prosody, and temporal auditory processing in the absence of significant deficits in the comprehension of written language, expressive language production, or peripheral auditory function. Furthermore, the patient demonstrates relatively preserved function in other aspects of audition such as sound localization, voice recognition, and perception of animal noises and environmental sounds. This case study demonstrates that auditory agnosia is possible following traumatic brain injury in a child, and illustrates the necessity of assessment with a wide variety of auditory stimuli to fully characterize auditory agnosia in a single individual. 相似文献
130.
Paul?Mooney Joseph?B.?RyanEmail author Brad?M.?Uhing Robert?Reid Michael?H.?Epstein 《Journal of Behavioral Education》2005,14(3):203-221
The purpose of this review was to report on the effectiveness and focus of academic self-management interventions for children and adolescents with emotional and behavioral disorders. Twenty-two studies published in 20 articles and involving 78 participants met inclusionary criteria. The overall mean effect size (ES) across those studies was 1.80 (range –0.46 to 3.00), indicating effects were generally large in magnitude and educationally meaningful. Self-monitoring interventions were the predominant type of self-management technique used by researchers. The mean ES for intervention types were self-evaluation (1.13), self-monitoring (1.90), strategy instruction techniques (1.75), self-instruction techniques (2.71), and multiple-component interventions (2.11). Interventions targeted improvement in math calculation skills more than any other area. The mean ES by academic area were math interventions (1.97), writing (1.13), reading (2.28), and social studies (2.66). There was evidence to support a claim of the generalization and maintenance of findings. Implications, limitations, and areas for future research are discussed. 相似文献