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961.
If an illusion of self-tilt is involved in rod-and-frame test performance, then instructions to adjust the rod to the body midline (egocentric instructions) should result in less rod adjustment error than the standard instructions for the rod-and-frame test to adjust the rod to the gravitational vertical. Two experiments were designed to examine this possibility. The results of the first experiment indicate that the tilted rod-and-frame display induces an illusion of self-tilt in the opposite direction. Significant differences between instructional conditions were found in the second experiment as expected. Other rod-and-frame studies are discussed in view of these findings.  相似文献   
962.
The use of employer records to assess shiftwork effects is discussed. Methods for gaining access to records are covered, along with some of the problems involved in evaluating the data. Five general sources of data are described.  相似文献   
963.
This study examined the relationship involving children's level of anxiety, defensiveness, and play patterns 1 week prior to, during, and 1 week after hospitalization for minor surgery. A 7-month follow up was also conducted in order to assess the children's recall for hospital events and coping style. The results suggested that two classes of children could be identified. The children in one group distinguished themselves in terms of their disposition to engage in the work of worrying (i.e., were low defensive prior to hospitalization, actively played with stress-related toys prior to hospitalization, and reported minimal distress and anxiety following surgery). Those in the second group were highly defensive, avoided playing with stress-related toys, and reported most anxiety following surgery. The parallel between children and adult patterns of dealing with surgery was considered in terms of Janis's (1958) model of coping with psychological stress.This research was supported by a grant from Canada Council, Grant No. S72-2314-52. The authors wish to thank the staff and children of Our Lady of Lourdes School of Waterloo, the Kitchener-Waterloo Hospital, and St. Mary's General Hospital for their cooperation. Appreciation is extended to Dr. Pat Bowers and Dr. Barney Gilmore for their help during the formative stages of this study and for their many constructive suggestions.  相似文献   
964.
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   
965.
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   
966.
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   
967.
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   
968.
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   
969.
970.
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   
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