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The author's goal was to discover if the generation and maintenance of the specific immune response resulted in alterations of reliable behaviors (i.e., behaviors correlated over time). The behaviors (ambulation, rearing, and interaction with a conspecific) of CD1 male mice were measured in a small open field, and several days later, the mice were immunized with antigens (either splenocytes from C57BL/6 mice or a mixture of sheep erythrocytes and goat serum). The same behaviors were recorded again some hours, or some days, after immunization. Immunizations and behavioral measurements were repeated at various intervals. Blood levels of antibodies to the antigens were measured 6 days after immunization. The recorded behaviors were consistent (according to Kendall coefficient of concordance). The mice mounted antibody responses to the antigens, yet no behavioral changes were apparent during the response. On the contrary, a single injection of E. coli lipopolysaccharide decreased ambulation and rearing. It is proposed that in healthy mice kept in normal conditions, the specific immune response may be unrelated to reliable behavioral changes.  相似文献   
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This study discusses the relation between television, computer games, and the Internet and antisocial aggressive behavior in under‐18s. Given that the media are an important source of socialization for children, this research examines which variables in media exposure lead to antisocial behavior in under‐18s. A sample of 93 participants (male and female), aged 13–18, answered an antisocial behavior inventory and a survey on computer gaming and TV viewing. Results show gender differences in the relation between media use and preference for violent media and direct and indirect aggressive behaviors. These findings support the idea that lack of interaction and role taking leads to deprived socialization and, in turn, to antisocial behavior.  相似文献   
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In choice reaction time tasks, subjects speed up before making an error, but slow down afterward to prevent the occurrence of a new error. In some trials, the correct response is preceded by an incorrect electromyographic (EMG) activation too small to reach the response threshold. In this article, we show that these incorrect EMG activations give rise to the same sequential effects as overt errors: Before a trial containing an incorrect EMG activation, subjects speed up, whereas after that trial, they slow down. These activations reflect errors that have been detected, inhibited, and corrected in time. As such, they index the involvement of online executive control.  相似文献   
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After defining, for each many-sorted signature Σ = (S, Σ), the category Ter(Σ), of generalized terms for Σ (which is the dual of the Kleisli category for \mathbb TS{\mathbb {T}_{\bf \Sigma}}, the monad in Set S determined by the adjunction TS \dashv GS{{\bf T}_{\bf \Sigma} \dashv {\rm G}_{\bf \Sigma}} from Set S to Alg(Σ), the category of Σ-algebras), we assign, to a signature morphism d from Σ to Λ, the functor dà{{\bf d}_\diamond} from Ter(Σ) to Ter(Λ). Once defined the mappings that assign, respectively, to a many-sorted signature the corresponding category of generalized terms and to a signature morphism the functor between the associated categories of generalized terms, we state that both mappings are actually the components of a pseudo-functor Ter from Sig to the 2-category Cat. Next we prove that there is a functor TrΣ, of realization of generalized terms as term operations, from Alg(Σ) × Ter(Σ) to Set, that simultaneously formalizes the procedure of realization of generalized terms and its naturalness (by taking into account the variation of the algebras through the homomorphisms between them). We remark that from this fact we will get the invariance of the relation of satisfaction under signature change. Moreover, we prove that, for each signature morphism d from Σ to Λ, there exists a natural isomorphism θ d from the functor TrL °(Id ×dà){{{\rm Tr}^{\bf {\bf \Lambda}} \circ ({\rm Id} \times {\bf d}_\diamond)}} to the functor TrS °(d* ×Id){{\rm Tr}^{\bf \Sigma} \circ ({\bf d}^* \times {\rm Id})}, both from the category Alg(Λ) × Ter(Σ) to the category Set, where d* is the value at d of the arrow mapping of a contravariant functor Alg from Sig to Cat, that shows the invariant character of the procedure of realization of generalized terms under signature change. Finally, we construct the many-sorted term institution by combining adequately the above components (and, in a derived way, the many-sorted specification institution), but for a strict generalization of the standard notion of institution.  相似文献   
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The purpose of this study was to examine the effects of focus of attention cues on movement coordination and coordination variability in the lower extremity. Twenty participants performed the standing long jump under both internal and external focus of attention conditions. A modified vector coding technique was used to evaluate the influence of attentional focus cues on lower extremity coordination patterns and coordination variability during the jumps. Participants jumped significantly further under an external focus of attention condition compared with an internal focus of attention condition (p = .035, effect size = .29). Focus of attention also influenced coordination between the ankle and knee, F(6, 19) = 2.87, p = .012, effect size = .388, with participants primarily using their knees under the internal focus of attention, and using both their ankles and knees under the external focus of attention. Attentional focus cues did not influence ankle-knee, F(1, 19) = 0.02, p = .98, effect size = .02, or hip-knee, F(1, 19) = 5.00, p = .49, effect size = .16, coordination variability. Results suggest that while attentional focus may not directly influence movement coordination condition, there is still a change in movement strategy resulting in greater jump distances following an external focus of attention.  相似文献   
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