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151.
We study some operations that may be defined using the minimum operator in the context of a Heyting algebra. Our motivation comes from the fact that 1) already known compatible operations, such as the successor by Kuznetsov, the minimum dense by Smetanich and the operation G by Gabbay may be defined in this way, though almost never explicitly noted in the literature; 2) defining operations in this way is equivalent, from a logical point of view, to two clauses, one corresponding to an introduction rule and the other to an elimination rule, thus providing a manageable way to deal with these operations. Our main result is negative: all operations that arise turn out to be Heyting terms or the mentioned already known operations or operations interdefinable with them. However, it should be noted that some of the operations that arise may exist even if the known operations do not. We also study the extension of Priestley duality to Heyting algebras enriched with the new operations.  相似文献   
152.
Numerous studies have shown that alcohol intake causes neuropsychological disorders that affect various brain structures. The ?premature ageing? hypothesis proposes that the brain areas of alcoholics undergo deterioration similar to that observed in old age. We investigated whether alcohol abuse by young people (binge drinking) causes alterations comparable to some found in elderly people. Ninety-one people were divided into four groups: a) young people who abused alcohol; b) young people who drank alcohol in moderation; c) young people who did not drink alcohol; and d) elderly adults without any significant cognitive deterioration. All of them were assessed with a neuropsychological battery. We observed some similarities in the results obtained by young drinkers and the elderly participants, which would provide some support for the hypothesis of premature aging. The tasks that young drinkers performed worse were those related to executive functions, in which the prefrontal cortex plays an essential role. We also found differences between the two groups of young drinkers (moderate and high consumption), which leads us to believe that the amount of alcohol consumed and the pattern of consumption are factors to consider in relation to cognitive impairment.  相似文献   
153.
Extreme Betting     
It is often thought that bets on the truth of known propositions become irrational if the losing costs are high enough. This is typically taken to count against the view that knowledge involves assigning credence 1. I argue that the irrationality of such extreme bets can be explained by considering the interactions between the agent and the bookmaker. More specifically, the agent’s epistemic perspective is altered by the fact that the bookmaker proposes that unusual type of bet. Among other things, being willing to offer a bet with unnecessarily harmful losing costs is likely to undermine the baseline level of trustworthiness required for it to be rational to engage in betting exchanges. This sort of explanation does not require granting either that we assign credence lower than 1 to known propositions or that knowledge is sensitive to practical stakes. Moreover, I show that, in our ordinary lives, we frequently perform actions that we know would be disastrous if certain conditions did not obtain. This behaviour can be seen as a form of implicit extreme betting and, nevertheless, it is often rational.  相似文献   
154.
Qualitative methods that analyze the coherence of expository texts not only are time consuming, but also present challenges in collecting data on coding reliability. We describe software that analyzes expository texts more rapidly and produces a notable level of objectivity ETAT (Expository Text Analysis Tool) analyzes the coherence of expository texts. ETAT adopts a symbolic representational system, known asconceptual graph structures. ETAT follows three steps: segmentation of a text into nodes, classification of the unidentified nodes, and linking the nodes with relational arcs. ETAT automatically constructs a graph in the form of nodes and their interrelationships, along with various attendant statistics and information about noninterrelated, isolated nodes. ETAT was developed in Java, so it is compatible with virtually all computer systems.  相似文献   
155.
This article focuses on neuropsychological functioning at moderate, high, and extreme altitude. This article summarizes the available literature on respiratory, circulatory, and brain determinants on adaptation to hypoxia that are hypothesized to be responsible for neuropsychological impairment due to altitude. Effects on sleep are also described. At central level, periventricular focal damages (leuko-araiosis) and cortical atrophy have been observed. Frontal lobe and middle temporal lobe alterations are also presumed. A review is provided regarding the effects on psychomotor performance, perception, learning, memory, language, cognitive flexibility, and metamemory. Increase of reaction time and latency of P300 are observed. Reduced thresholds of tact, smell, pain, and taste, together with somesthetic illusions and visual hallucinations have been reported. Impairment in codification and short-term memory are especially noticeable above 6,000 m. Alterations in accuracy and motor speed are identified at lower altitudes. Deficits in verbal fluency, language production, cognitive fluency, and metamemory are also detected. The moderating effects of personality variables over the above-mentioned processes are discussed. Finally, methodological flaws found in the literature are detailed and some applied proposals are suggested.  相似文献   
156.
Personality disorders (PDs) are still classified through categorical taxonomies that are at odds with current research findings. Dimensional models provide a suitable alternative for measuring individual differences. However, as they have traditionally lacked a clear definition of the "disorder" construct, the clinical utility of these models has been limited. This study tests whether Cloninger's dimensional model is able to capture two domains: the features that differentiate PD subtypes from each other and the common core features underlying all PDs. Seventy-four drug dependent patients were independently assessed using the SCID-II and Cloninger's TCI. There was a slight relationship between TCI temperament dimensions and the DSM personality disorder subtypes, but the association was not specific enough to allow differential diagnosis. The character dimension Self-Directedness was strongly associated with the presence and severity of all PDs, irrespective of subtype, correctly classifying 77% of subjects. Character dimensions are a reliable, valid and low-cost tool for detecting PDs in drug abusers and may help to provide an operational definition of the common core features underlying all PDs.  相似文献   
157.

Volume Contents

Contents of Volume 66  相似文献   
158.
Predictors of Condom Use in Mexican Migrant Laborers   总被引:5,自引:0,他引:5  
The purpose of this study was to explore predictors of condom use with occasional sex partners and regular sex partners, as well as carrying condoms in a new high-risk group for HIV infection, Mexican migrant laborers. This study extends previous findings by (1) exploring additional predictors not previously examined, (2) utilizing a large sample of male and female Mexican migrant laborers, (3) carefully controlling for the effects of various demographic and lifestyle variables related to condom use, and (4) assessing the interactive effects of gender on predictors of condom use. Snowball sampling was used to survey 501 adult Mexican migrant laborers. Results revealed that condom use with occasional sex partners was predicted by carrying condoms and condom self-efficacy and that women were more likely to use condoms with occasional partners when both men and women knew someone with HIV/AIDS. Condom use with regular sex partners was predicted by procondom social norms, less negative attitudes toward condoms, not knowing someone with HIV/AIDS, and condom self-efficacy. Carrying condoms was predicted by procondom social norms, less negative attitudes toward condoms, condom self-efficacy, worry about contracting HIV/AIDS, and women were more likely than men to carry condoms when both men and women were married. Understanding these findings, future research directions, and implications for condom promotion strategies with Mexican migrant laborers are discussed.  相似文献   
159.
The genetic and environmental etiologies of individual differences in printed word recognition and related skills were explored in 440 identical and fraternal twin pairs between 8 and 18 years of age. A theoretically driven measurement model identified five latent variables: IQ, phoneme awareness, word recognition, phonological decoding, and orthographic coding. Cholesky decomposition models on these five latent constructs revealed the existence of both common and independent genetic effects, as well as non-shared environmental influences. There was evidence for moderate genetic influences common between IQ, phoneme awareness, and word-reading skills, and for stronger IQ-independent genetic influences that were common between phoneme awareness and word-reading skills, particularly phonological decoding. Phonological and orthographic coding skills in word recognition had both significant common and significant independent genetic influences, with implications for "dual-route" and "connectionist" reading models, subtypes of reading disabilities, and the remediation of reading disabilities.  相似文献   
160.
Cognitive, individual differences, and intergroup contact factors were examined in the formation of attitudes about human rights and ethnic bias in two studies conducted in Spain. A 7‐item scale measuring knowledge about human rights laws in Spain and the European Union was used in both studies. Participants were university students enrolled at the Universidad Autónoma de Madrid. In study one, participant (n = 127) knowledge about human rights laws, intergroup contact, Right Wing Authoritarianism (RWA), and Gough's Prejudice/Tolerance (Pr/To) scale were examined in relationship to bias towards Gitanos. Findings revealed that knowledge about human rights and social status variables (gender and age) were not significant predictors of Gitano bias, whereas Pr/To, RWA, and contact were all (R2 = .28) significant predictors of bias against Gitanos. Findings provided cross‐cultural replication (Dunbar & Simonova, in press) of the relationship of Pr/To and RWA to Gitano bias. In study two, participant (n = 100) knowledge and feelings (measured on a three‐item semantic differential scale) about human rights laws, Pr/To, and RWA were examined in relation to strategies influencing peer attitudes about human rights on the Raven Social Influence Inventory (RSII) scale. Findings indicated that knowledge about human rights laws were correlated (r = .47, p < .001) with positive feelings about these laws. Results of a hierarchical regression analysis, controlling for knowledge about human rights laws and participants' social status, found that the Prejudice/Tolerance scale and feelings about human rights were related with both hard (R2 = .11) and soft (R2 = .08) social influence strategies influencing peer human rights attitudes on the RSII. Men and higher‐scoring participants on Pr/To both employed more hard social influence strategies. Findings indicate that while knowledge of human rights laws is unrelated to ethnic bias, more accurate knowledge is correlated to more positive feelings about laws meant to protect the rights of ethnic minorities.  相似文献   
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