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291.
The purpose of this study was to develop, implement, and evaluate a psychoeducational group intervention that addressed the needs of adult children caring for aging parents. The intervention consisted of four 2-hour sessions and included 70 care givers, 54 to 72 years of age, who were currently caring for a parent 60 years of age or older. A delayed-treatment, control-group design with follow-up after a 4-week interval was used to study three primary variables identified through an extensive literature review as essential for care givers. These included knowledge, care giver burden, and skill development. Skill development did not change following participation, nor did care giver burden variables measured. Significant increases were found at the .05 level for knowledge, overall coping resources, and self disclosure following group participation.  相似文献   
292.
How does the brain extract invariant properties of variable-rate speech? A neural model, called PHONET, is developed to explain aspects of this process and, along the way, data about perceptual context effects. For example, in consonant-vowel (CV) syllables, such as /ba/ and /wa/, an increase in the duration of the vowel can cause a switch in the percept of the preceding consonant from /w/ to /b/ (J.L. Miller & Liberman, 1979). The frequency extent of the initial formant transitions of fixed duration also influences the percept (Schwab, Sawusch, & Nusbaum, 1981). PHONET quantitatively simulates over 98% of the variance in these data, using a single set of parameters. The model also qualitatively explains many data about other perceptual context effects. In the model, C and V inputs are filtered by parallel auditory streams that respond preferentially to the transient and sustained properties of the acoustic signal before being stored in parallel working memories. A lateral inhibitory network of onset- and rate-sensitive cells in the transient channel extracts measures of frequency transition rate and extent. Greater activation of the transient stream can increase the processing rate in the sustained stream via a cross-stream automatic gain control interaction. The stored activities across these gain-controlled working memories provide a basis for rate-invariant perception, since the transient-to-sustained gain control tends to preserve the relative activities across the transient and sustained working memories as speech rate changes. Comparisons with alternative models tested suggest that the fit cannot be attributed to the simplicity of the data. Brain analogues of model cell types are described.  相似文献   
293.
The purpose of this study was to develop and test a multidimensional model of parental and family influences on risk for substance use in inner-city African-American primary grade children and their adolescent siblings. The risk factors investigated were conceptually grouped into three broad domains of family influences and the respective indices computed: parental risk attributes, family risk attributes, and parenting styles. Parenting styles were captured as indicators of a latent construct, poor parenting. In study 1, we hypothesized that the parental and family risk variables would be mediated through parenting styles to predict intentions to use drugs, actual drug use, positive drug attitudes, and negative drug attitudes in a sample of 455 inner-city African-American families and their primary-grade children. In study 2, the substance use risk model was tested on a sample of 59 adolescent sibilings to determine whether the pattern of parental and family factors that contributed to early high-risk attitudes and behaviors in children would predict drug attitudes and behaviors in teen siblings. The results confirmed our expectations that parental and family risks were important predictors of childrens' negative drug attitudes and intentions to use drugs in the future and that positive parental and family characteristics would protect against future risk by enhancing negative drug attitudes. Also, substance use attitudes and behaviors in the teen siblings were predicted primarily by family risk characteristics. The family risk index also predicted frequency of use of hard drugs, but only when mediated through poor parenting. The implications of these results for future research are discussed.  相似文献   
294.
Young children testify as witnesses with increasing frequency. This article describes the law regarding children's competence to testify. The article focuses on: (1) the elements of testimonial competence, including perception, memory, understanding the difference between the truth and a lie, and understanding the duty to tell the truth in court; (2) the requirement of personal knowledge of relevant facts; and (3) the requirement that the child take a religious oath or a secular affirmation.  相似文献   
295.
It has been shown previously that rats which have learned a response when hungry will continue to make that response when tested satiated, a phenomenon labeled resistance to satiation. Here we showed that rats which were previously trained hungry will learn a new response for the opportunity to consume pellets in a new situation when tested satiated. In four experiments various groups received each of the components of the training given when rats learn an instrumental response when hungry. Rats were placed in the goalbox of a straight alley and given food pellets when hungry or were hungry only in their home cages prior to running a straight alley in the satiated test in Experiment 1. In Experiments 2, 3, and 4 learning of a differential conditioning problem for pellets in S+ (nonreward in S?) was measured in the satiated test. Groups given pellets in their home cages when hungry with or without alley exposure learned to run more rapidly in S+ than in S? in the satiated test phase. The tendency to eat pellets in the apparatus and the reinforcing effect of eating the pellets was larger for rats which ate the pellets when hungry in their home cage than for rats which ate the pellets when satiated in their home cage. Being hungry in the home cage with no pellets was not sufficient to produce eating or running for pellets in the satiated test, indicating that any inherent reinforcing effect of the pellets is not sufficient to produce eating or running, and that incomplete satiation cannot account for the learning. These data indicate that a reinforcing effect of eating pellets under satiation is an important determiner of resistance to satiation.  相似文献   
296.
Two experiments evaluated the effectiveness of response prevention when prevention periods were interpolated with instrumental trials which permitted performance of the originally trained instrumental behavior. In Experiment 1, interpolation of instrumental escape trials under shock and nonshock procedures reliably reduced prevention's influence on performance and yielded extinction responding similar to that of pseudo-prevention controls. In Experiment 2 interpolation of instrumental escape trials under nonshock conditions yielded passive avoidance performance similar to that of pseudo-prevention controls but reliably different from that of a regular prevention group.  相似文献   
297.
To assess the effectiveness of vocational guidance procedures proposed for inclusion in a computer-based vocational exploration system, 139 eleventh-grade male subjects were randomly assigned to three experimental groups and a control group. One group was given a computer-generated accuracy of self-knowledge feedback, another group was taught an occupational classification scheme, a third group experienced both. Utilizing a method of explicit comparison between students' measured characteristics and the measured characteristics of occupational norm groups, the results showed students in the groups receiving feedback increased in the appropriateness of the occupational level of their first occupational choice. In addition, students in the combined treatment group increased in the appropriateness of the level of their total occupational preferences. A delayed posttest indicated that these increases persisted.  相似文献   
298.
An experimental group of 792 tenth graders spent from 1 to 17 hr (average 3 hr) on ECES, a computer-based educational and occupational exploration system.Gains on a test of vocational maturity administered at the beginning and end of the school year were compared with a control group of 1453 tenth graders, matched on relevant variables. ECES users showed larger gains than nonusers in (1) degree of planfulness and (2) knowledge and use of resources for career exploration, as measured by the Career Development Inventory, not in information about education, occupations and career decision making. Gains were related to amount of time spent on ECES but male-female differences were not exhibited.  相似文献   
299.
300.
A grade of A was given in an introductory statistics course for meeting a set of contingencies that included no work outside of class (except by request), near-perfect performance on exams following each unit of work in a programmed text, correction of all exam errors, self pacing of work, and the chance to finish the course early. A grade of incomplete was given otherwise. Correlations among performance measures failed to show any meaningful relationships between time taken to finish the course, errors made on exams, and errors made in the programmed text. Responses to a five-part questionnaire were overwhelmingly favorable to the course, but did not vary as a function of grade point average, time taken to finish the course, or number of errors made on exams. The uniformly high level of performance, the students' lack of interest in social contact with the instructor during class, and the absence of drop-outs are all attributed to the contingencies employed, chief among which, according to the instructor's judgment and student rankings, were self-pacing, frequent non-punitive exams and a guaranteed grade of A for near-perfect work at every stage.  相似文献   
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