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991.
A central-incidental task of selective attention was administered to 100 learning-disabled boys — 48 younger children (81/2–101/2 years) and 52 older children (101/2–121/2 years). Subjects at both age levels were assigned to one of four conditions: (a) a standard condition; (b) a rehearsal condition, in which subjects were taught a verbal rehearsal strategy; (c) a reinforcement condition, in which correct responses were rewarded; and (d) a combined rehearsal-reinforcement condition. Older subjects recalled more central task but not more incidental task information than younger subjects. A measure of selective attention efficiency was also greater for older than for younger subjects. Central recall in the rehearsal-reinforcement condition was greater than in any other condition. Central recall was greater in the rehearsal condition than in the standard and reinforcement conditions. Selective attention efficiency was greater for both rehearsal conditions than for both nonrehearsal conditions. Incidental recall was higher for reinforcement subjects than for rehearsal subjects. Results suggest that induced verbal rehearsal improves central recall and selective attention in learning-disabled children. Reinforcement alone does not improve central recall but may when paired with rehearsal.This article is based on a Ph.D. dissertation completed by the senior author at the University of Virginia. Preparation of this article was supported in part by a contract (300-77-0495) from the Bureau of Education for the Handicapped, Office of Education, for the University of Virginia Learning Disabilities Research Institute.  相似文献   
992.
Vocalizations are preceded by slow EEG waves over inferior frontal scalp regions, but some controversy exists as to whether these slow potentials are left-lateralized as a function of speech. In this study both speech and non-speech vocalizations were studied, under conditions of repetitive and variable production. Averaged responses over the speech musculature, including the temporalis, masseter, orbicularis oris, and mylohyoid muscles, as well as the eyes and tongue, were calculated simultaneously with scalp EEG averages. The responses of the temporalis and masseter muscles, as well as that of the tongue, were correlated with EEG sites at specific latencies prior to speech, suggesting that no part of the inferior frontal EEG record was free from myogenic confounds. In addition, all significant EEG differences between speech and non-speech conditions were subsequently eliminated by covariance analysis, using selected muscle channels as covariates. Previous reports of asymmetrical “speech potentials” in the EEG probably reflected a combination of several myogenic confounds.  相似文献   
993.
Children 1 and 3 years of age were given a two-choice spatial discrimination task. They were placed in front of a barrier and encouraged to walk around it; one route around the barrier was blocked. Three experiments studied the effects of different types of experience with this spatial problem. The first examined trial and error experience, in which the child was allowed to walk the route he or she had chosen. Although most children readily learned to choose the open route, the pattern of choices indicated that 3-year-olds were more likely to achieve a learning criterion after an error than 1-year-olds. A second experiment looked at the effects of showing the children the layout of the problem prior to trial and error experience. The 3-year-olds were again more likely than the 1-year-olds to achieve criterion after an error; furthermore, they were likely to know the correct route on the first trial. The third experiment let the children watch their parents take the correct route. This procedure eliminated age differences in performance. The initial choices of the 1-year-olds indicated that they were likely to know the correct route, and if they did not, they were just as likely to learn from their mistakes as the 3-year-olds. The data were interpreted within a mathematical model of learning. Based upon these analyses, we propose two developmental trends. One involves a growth in sensitivity to the consequences of a choice of route. The other is a progression from social learning to more independent and ideational methods of spatial problem solving.  相似文献   
994.
The purpose of this investigation was to determine the abilities of children to use the adjoining mechanism in combining two constituent sentences with the temporal adjoiners: after, before, until, when, and while. To elicit responses, a sentence repetition task was devised that included these five temporal adjoiners in four different syntactic environments: transitive sentences with the adjoiner and the subordinate clause following the main clause, transitive sentences with the adjoiner and the subordinate clause preceding the main clause, intransitive sentences with the adjoiner and the subordinate clause following the main clause, and intransitive sentences with the adjoiner and the subordinate clause preceding the main clause. The 30 were between the ages of 4O and 66 years. They were average children who were free from any known emotional disturbance, who were acquiring Standard American English as a native language, who had normal speech and hearing, and whose parents had neither very high nor very low socioeconomic status. To the extent that the children in this study were representative of normal-speaking children of their ages, certain general conclusions were drawn. Children begin to use the temporal adjoining mechanism early, but they do not master it by the age of 66 years. The ability to use the adjoiners, nor is it equal for different syntactic structures nor for all degrees of semantic complexity. After, before, and when appear earlier than while and until. A rapid period of growth in learning to use the temporal adjoining mechanism occurs between the ages of 4 and 5 years. However, a plateau of learning appears to be reached between the ages of 5 and 6 years. In general, children first learn to use the temporal adjoining mechanism in intransitive sentences with the adjoining link in the middle or at the beginning of the utterance. Next, they learn to use it in transitive sentences with the adjoining link at the beginning of the utterance. Finally, they learn to use it in transitive sentences with the adjoining link in the middle of the utterance. In transitive sentences, children appear to learn the rule for placing the subordinate clause at the beginning of the utterance when temporally adjoining two constituent sentences before they learn the base structure rule. In intransitive sentences, they appear to learn the rule for placing the subordinate clause at the beginning of the utterance when temporally adjoining two constituent sentences at the same time that they learn the base structure rule. The underlying semantic relationships that are expressed by specific temporal adjoiners are important determinants of children's abilities to use these adjoiners. In linguistic evaluations, one should consider the syntactic environment in which the temporal adjoiner occurs and assume that after, before, and when are developmentally earlier than while and until.  相似文献   
995.
Rats shocked once through a wire-wrapped stationary prod mounted on the wall of a test chamber incorporated the bedding material covering the chamber floor into a defensive reaction. When tested 1 min later, they approached the prod and buried it. Evidence was provided by three separate studies of this burying response that rats had learned about the association of both the position and brightness of the prod with shock after this single conditioning trial. In Experiment 1, the amount of burying decreased if either the position or brightness of the prod had been changed prior to the test. In Experiments 2 and 3, rats were shocked through one of two prods (white or black) mounted on opposite walls of the test chamber. When the positions of the prods were unchanged for the test, almost every subject buried the prod through which it had been shocked, even when the conditioning-test interval was 24 hr; whereas, each rat directed substantial amounts of bedding material at both prods when the positions of the two prods were reversed. Thus, discriminated “avoidance” learning can be rapid, reliable, and enduring when shock is administered “by” a clearly defined stimulus object, i.e., when cue and consequence are spatially contiguous.  相似文献   
996.
997.
Significant job-relatedness was found for a posttraining job knowledge test criterion using an application of Lawshe's content validity method. The aide test was used as a criterion to assess the predictive validity of a vocabulary test and a civil service test with samples of black ( N = 43) and white ( N = 62) psychiatric aides. Significant validities were found on both tests, but a vocabulary test proved to be the better predictor of the criterion in both samples. The obtained validities were discussed in terms of differential validity, test fairness, and sample size. This study demonstrated that a content validity method could be applied to criteria as well as selection tests. It was concluded that content validity methods may be able to help solve the problem of criterion relevance in validation research by providing quantitative evidence of the job-relatedness of criteria.  相似文献   
998.
This article explores the legal, ethical, and practical considerations underlying the requirement for acquiring parental consent prior to a psychological assessment of children in school settings. Publ. L. 94-142 now mandates that parents for all children potentially labeled as handicapped give permission for a preplacement evaluation. This article reviews in detail specific aspects of that mandate, argues that this procedure be generalized to all situations where psychologists propose to evaluate children by reviewing both current ethical codes and standards for practice and public policy which favors such an undertaking. Finally, the authors indicate methods for implementing the mandate by discussing such issues as who should obtain consent and what information parents should receive prior to giving consent.  相似文献   
999.
People recall taboo words better than neutral words in many experimental contexts. The present rapid serial visual presentation (RSVP) experiments demonstrated this taboo-superiority effect for immediate recall of mixed lists containing taboo and neutral words matched for familiarity, length, and category coherence. Under binding theory (MacKay et al., 2004), taboo superiority reflects an interference effect: Because the emotional reaction system prioritizes binding mechanisms for linking the source of an emotion to its context, taboo words capture the mechanisms for encoding list context in mixed lists, impairing the encoding of adjacent neutral words when RSVP rates are sufficiently rapid. However, for pure or unmixed lists, binding theory predicted no better recall of taboo-only than of neutral-only lists at fast or slow rates. Present results supported this prediction, suggesting that taboo superiority in immediate recall reflects context-specific binding processes, rather than context-free arousal effects, or emotion-linked differences in rehearsal, processing time, output interference, time-based decay, or guessing biases.  相似文献   
1000.
The likelihood of benefit is fundamental to decision making about newborn screening. But benefit is construed in different ways by different stakeholders. This article begins with a review of benefit as considered historically by various expert panels and organizations. We then show how 78 conditions fared when experts recently rated them on benefit using a scoring system recommended by a task force of the American College of Medical Genetics. Finally, we analyze how benefit is reflected in the public comments submitted in response to the ACMG report. Results show that benefit has been and remains a core consideration for screening decisions. Historically the focus has been on improved physical health as a result of medical treatment; however, in only 4 of the 78 conditions rated does newborn screening prevent all negative consequences. In fact the majority of both core conditions (51.7%) and secondary targets (87.5%) recommended in the ACMG report were rated as having treatments that prevented only some negative consequences. All conditions rated had perceived benefits for family and society, but currently no conditions are screened on the basis of family or societal benefits alone. No agreed-upon threshold exists for what would be considered meaningful benefit, and stakeholder groups differ in their perceptions of benefit. We conclude by suggesting several key research studies needed to further inform public policy.  相似文献   
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