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21.
The prevalence and correlates of depressive symptoms following childhood traumatic brain injuries (TBI) were examined using data drawn from a prospective longitudinal study. Participants included 38 children with severe TBI, 51 with moderate TBI, and 55 with orthopedic injuries (OI). Assessments occurred shortly after injury (baseline) and at 6- and 12-month follow-ups. Children completed the Child Depression Inventory (CDI). Parents rated depressive symptoms using the Child Behavior Checklist (CBC), with baseline ratings reflecting premorbid status. Assessments also included measures of children's neurocognitive functioning and the family environment. The three groups did not differ overall in self-reported symptoms on the CDI, but did display different trends over time. The three groups did not differ on parent ratings of premorbid depressive symptoms on the CBC, but parents reported more depressive symptoms in the TBI groups than in the OI group at 6- and 12-month follow-ups. Child and parent reports were correlated for children in the TBI groups, but not for those in the OI group. Depressive symptoms were related to socioeconomic status in all groups. Socioeconomic status also was a significant moderator of group differences, such that the effects of TBI were exacerbated in children from more disadvantaged homes. Although self-reports of depressive symptoms were related inconsistently to children's verbal memory, parent reports of depressive symptoms were unrelated to IQ or verbal memory. The findings suggest that TBI increases the risk of depressive symptoms, especially among more socially disadvantaged children, and that depressive symptoms are not strongly related to post-injury neurocognitive deficits.  相似文献   
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This study had three objectives: (1) to assess the relationship between the single nucleotide polymorphism (SNP) rs1789891 in the alcohol dehydrogenase gene cluster and alcohol dependence and affective disorders; (2) to assess the differences in the Regulative Theory of Temperament (RTT) traits between an alcohol dependent group, an affective disorders group, and a healthy group; and (3) to assess the relationship between rs1789891 and temperament traits in a healthy group, taking into account the interaction of genotype and sex. The SNP rs1789891 was genotyped in a group of 194 alcohol dependent men, aged 21 to 71 years; 137 patients with affective disorders, including 51 males and 86 females, aged 19 to 85 years; and a group of 207 healthy individuals, including 89 males and 118 females, aged 18 to 71 years. Temperament traits (briskness, perseveration, sensory sensitivity, emotional reactivity, endurance, and activity) were assessed in all groups using the Formal Characteristics of Behaviour‐Temperament Inventory. The comparative analysis of genotypic frequencies showed no significant differences between patients with alcoholism or affective disorders and those in the control group. Alcohol dependent men and the affective disorder group were characterised by higher levels of emotional reactivity (p‐value 1.4e‐5 and 9.84e‐7, respectively) and lower levels of briskness, sensory sensitivity, endurance, and activity (p‐value from 3.76e‐8 to 0.012) when compared to the healthy group. The rs1789891 polymorphism was associated with briskness (= 0.02), sensory sensitivity (= 0.036), and activity (= 0.049). None of the results were statistically significant after Bonferroni correction.  相似文献   
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A new machine learning approach known as motivated learning (ML) is presented in this work. Motivated learning drives a machine to develop abstract motivations and choose its own goals. ML also provides a self-organizing system that controls a machine’s behavior based on competition between dynamically-changing pain signals. This provides an interplay of externally driven and internally generated control signals. It is demonstrated that ML not only yields a more sophisticated learning mechanism and system of values than reinforcement learning (RL), but is also more efficient in learning complex relations and delivers better performance than RL in dynamically-changing environments. In addition, this paper shows the basic neural network structures used to create abstract motivations, higher level goals, and subgoals. Finally, simulation results show comparisons between ML and RL in environments of gradually increasing sophistication and levels of difficulty.  相似文献   
25.
Czelakowski  Janusz 《Studia Logica》2003,74(1-2):181-231
The paper is conceived as a first study on the Suszko operator. The purpose of this paper is to indicate the existence of close relations holding between the properties of the Suszko operator and the structural properties of the model class for various sentential logics. The emphasis is put on generality both of the results and methods of tackling the problems that arise in the theory of this operator. The attempt is made here to develop the theory for non-protoalgebraic logics.  相似文献   
26.
The present paper is thought as a formal study of distributive closure systems which arise in the domain of sentential logics. Special stress is laid on the notion of a C-filter, playing the role analogous to that of a congruence in universal algebra. A sentential logic C is called filter distributive if the lattice of C-filters in every algebra similar to the language of C is distributive. Theorem IV.2 in Section IV gives a method of axiomatization of those filter distributive logics for which the class Matr (C) prime of C-prime matrices (models) is axiomatizable. In Section V, the attention is focused on axiomatic strengthenings of filter distributive logics. The theorems placed there may be regarded, to some extent, as the matrix counterparts of Baker's well-known theorem from universal algebra [9, § 62, Theorem 2].The contents of this paper were presented in a talk at the 7th International Congress of Logic, Methodology and Philosophy of Science held at Salzburg, Austria, in July 1983. In abstracted form the paper was published in Abstracts of the 7th Congress, Vol. 2, pp. 39– 42. We take this opportunity to thank Professor Paul Weingartner and Doctor Georg Dorn from Salzburg for their (not fulfilled) wish to publish the present version in a special volume containing a selection of contributions to the 7th Congress.  相似文献   
27.
In the first section logics with an algebraic semantics are investigated. Section 2 is devoted to subdirect products of matrices. There, among others we give the matrix counterpart of a theorem of Jónsson from universal algebra. Some positive results concerning logics with, finite degrees of maximality are presented in Section 3.  相似文献   
28.
The class of equivalential logics comprises all implicative logics in the sense of Rasiowa [9], Suszko's logicSCI and many Others. Roughly speaking, a logic is equivalential iff the greatest strict congruences in its matrices (models) are determined by polynomials. The present paper is the first part of the survey in which systematic investigations into this class of logics are undertaken. Using results given in [3] and general theorems from the theory of quasi-varieties of models [5] we give a characterization of all simpleC-matrices for any equivalential logicC (Theorem I.14). In corollaries we give necessary and sufficient conditions for the class of all simple models for a given equivalential logic to be closed under free products (Theorem I.18). Theorem I.17 can be generalized as follows:For any equivalential logic C, clauses (i), (iii)and (v),formulated in Th.I.17,are equivalent.  相似文献   
29.
We propose a new schema for the deduction theorem and prove that the deductive system S of a prepositional logic L fulfills the proposed schema if and only if there exists a finite set A(p, q) of propositional formulae involving only prepositional letters p and q such that A(p, p) L and p, A(p, q) s q.  相似文献   
30.
The article deals with compatible families of Boolean algebras. We define the notion of a partial Boolean algebra in a broader sense (PBA(bs)) and then we show that there is a mutual correspondence between PBA(bs) and compatible families of Boolean algebras (Theorem (1.8)). We examine in detail the interdependence between PBA(bs) and the following classes: partial Boolean algebras in the sense of Kochen and Specker (§ 2), ortholattices (§ 3, § 5), and orthomodular posets (§ 4), respectively.  相似文献   
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