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251.
Leon Horsten 《Synthese》2005,146(1-2):111-127
Two simple generalized conversational implicatures are investigated :(1) the quantitative scalar implicature associated with ‘or’, and (2) the ‘not-and’-implicature, which is the dual to (1). It is argued that it is more fruitful to consider these implicatures as rules of interpretation and to model them in an algebraic fashion than to consider them as nonmonotonic rules of inference and to model them in a proof-theoretic way.  相似文献   
252.
There is a growing recognition of the central role of technology and knowledge management for market success of organizations. Little is empirically know, however, about this relationship. Drawing on the South African Innovation Survey, a unique dataset on innovative behavior of South African firms in manufacturing and services, this paper investigates the question to what extent and in which ways do technology and innovation management activities affect firms’ market position. Findings show that conducting technology strategy activities pays out. Moreover, especially a combination of internal and external technology audits seems to be beneficial for organizational performance.  相似文献   
253.
This study uses seven well-analyzed dreams to establish three empirical generalizations about dreams and works of art nested in dreams: (1) Those dreams attempt to deny a painful reality in some way depicted in the nested element; (2) they present an antithetical view of that reality (both denying and affirming); and (3) they are consistently associated with the problem of reality (the problem of deciding what is real or true). The explanation of these empirical generalizations is based on a hypothesis derived from Freud's 1911 formulation of the dream within a dream.  相似文献   
254.
In many regions of the brain, including the mammalian cortex, the strength of synaptic transmission can be bidirectionally regulated by cortical activity (synaptic plasticity). One line of evidence indicates that long-term synaptic potentiation (LTP) and long-term synaptic depression (LTD), correlate with the phosphorylation/dephosphorylation of sites on the alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit protein GluR1. Bidirectional synaptic plasticity can be induced by different frequencies of presynaptic stimulation, but there is considerable evidence indicating that the key variable is calcium influx through postsynaptic N-methyl-d-aspartate (NMDA) receptors. Here, we present a biophysical model of bidirectional synaptic plasticity based on [Ca2+]-dependent phospho/dephosphorylation of the GluR1 subunit of the AMPA receptor. The primary assumption of the model, for which there is wide experimental support, is that the postsynaptic calcium concentration, and consequent activation of calcium-dependent protein kinases and phosphatases, is the trigger for phosphorylation/dephosphorylation at GluR1 and consequent induction of LTP/LTD. We explore several different mathematical approaches, all of them based on mass-action assumptions. First, we use a first order approach, in which transition rates are functions of an activator, in this case calcium. Second, we adopt the Michaelis-Menten approach with different assumptions about the signal transduction cascades, ranging from abstract to more detailed and biologically plausible models. Despite the different assumptions made in each model, in each case, LTD is induced by a moderate increase in postsynaptic calcium and LTP is induced by high Ca2+ concentration.  相似文献   
255.
In the delivery of clinical services, outcomes monitoring (i.e., repeated assessments of a patient's response to treatment) can be used to support clinical decision making (i.e., recurrent revisions of outcome expectations on the basis of that response). Outcomes monitoring can be particularly useful in the context of established practice research networks. This article presents a strategy to disaggregate patients into homogeneous subgroups to generate optimal expected treatment response profiles, which can be used to predict and track the progress of patients in different treatment modalities. The study was based on data from 618 diagnostically diverse patients treated with either a cognitive-behavioral treatment protocol (n = 262) or an integrative cognitive-behavioral and interpersonal treatment protocol (n = 356). The validity of expected treatment response models to predict treatment in those 2 protocols for individual patients was evaluated. The ways such a procedure might be used in outpatient centers to learn more about patients, predict treatment response, and improve clinical practice are discussed.  相似文献   
256.
Targeted mutagenesis in mice has shown that genes from a wide variety of gene families are involved in memory formation. The efficient identification of genes involved in learning and memory could be achieved by random mutagenesis combined with high-throughput phenotyping. Here, we provide the first report of a mutagenesis screen that has generated memory mutants in the mouse. We tested a group of N-ethyl-N-nitrosourea (ENU) mutagenized mice in the conditioned fear paradigm. We screened for both dominant and recessive mutations that caused impairments in contextual or tone fear conditioning. Heritability testing confirmed three fear conditioning mutants, i.e., Forgetful, Slowlearner, and Scatterbrain. All three have a learning or short-term memory deficit in contextual fear conditioning. Forgetful was further characterized and showed a highly specific phenotype. The contextual fear-conditioning deficit was apparent when Forgetful was trained with tone-shock pairings, but not when trained with shock alone. The deficit was not due to changes in shock sensitivity or anxiety. Forgetful was not impaired in two other memory tests (hidden platform version of Morris water maze and object recognition). Our data show that a mutagenesis screen can generate mutant mice with highly specific memory phenotypes that can supplement existing mice with targeted mutations. Mapping of Slowlearner found linkage to a region of chromosome 12 (LOD score of 6.5 close to D12Mit171), which suggests that ENU mutants should enable the positional cloning of genes involved in memory formation.  相似文献   
257.
Faces are a rich and available source of social information, and the representation for faces is robust in adults (i.e. the face detection effect; Purcell & Stewart, 1988). The current study compared the developmental trajectory of the robustness of face perception against the trajectory for a non-face object. Participants (5-35 years old) were presented with rapid (17 and 33 millisecond) presentations of face and house stimuli and were instructed to identify the object category of the stimulus (face or house). There was an interaction between object type and age such that the developmental slope for face identification was steeper than the slope for house identification for the 17-millisecond presentation. These data show that faces are processed in a different way than a non-face object during the period from middle childhood through adolescence and adulthood, and this differential processing may involve the massive amount of exposure we have to faces.  相似文献   
258.
This paper continues a line of investigation begun in a previous paper on nested dreams and works of art in dreams (Balter 2005). Part I of the present paper seeks to establish that works of art with nested dreams and works of art within them display certain phenomena also observed in comparable dreams: (i) they unsuccessfully deny a painful reality represented in the nested element; (2) they present an antithetical view of that reality (both denying and affirming); and (3) they are consistently associated with the problem of reality (the problem of deciding what is real or true). Part II of this paper seeks to establish the heuristic value of this line of investigation in dreams and art to elucidate the origin of reality testing.  相似文献   
259.
The aesthetic illusion is the subjective experience that the content of a work of art is reality. It has an intrinsic relation to magic, an intrapsychic maneuver oriented toward modification and control of the extraspyschic world, principally through ego functioning. Magic is ontogenetically and culturally archaic, expresses the omnipotence inherent in primary narcissism, and operates according to the logic of the primary process. Magic is a constituent of all ego functioning, usually latent in later development. It may persist as an archaic feature or may be evoked regressively in global or circumscribed ways. It causes a general disinhibition of instincts and impulses attended by a sense of confidence, exhiliration, and exuberance. The aesthetic illusion is a combination of illusions: (1) that the daydream embodied by the work of art is the beholder's own, the artist being ignored, and (2) that the artistically described protagonist is a real person with a real "world." The first illusion arises through the beholder's emotional-instinctual gratification from his or her own fantasy-memory constellations; the second comes about because the beholder, by taking the protagonist as proxy, mobilizes the subjective experience of the imaginary protagonist's "reality." The first illusion is necessary for the second to take place; the second establishes the aesthetic illusion proper. Both illusions are instances of magic. Accordingly, the aesthetic illusion is accompanied by a heady experience of excitement and euphoria. The relation among the aesthetic illusion, magic, and enthusiasm is illustrated by an analytic case, J. D. Salinger's "The Laughing Man," Woody Allen's Play It Again, Sam, Don Quixote, and the medieval Cult of the Saints.  相似文献   
260.
10 experienced Shotokan karateka were tested on performance time and distance from a marker on the five Heian kata under normal sighted and blind-folded conditions. Whilst each kata's line of movement is different, it is the intention to start and finish at the same location. Analysis showed that despite an average of 16.8 yr. of training, whilst timing was not significantly affected on four of the kata by subjects being deprived of the visual sense, the group's mean change in distance from an original marker was significant for performances on three of the kata.  相似文献   
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