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121.
T1G3膀胱癌有高复发和进展倾向,选择恰当的治疗方法成为难题。使用BCG治疗可促肿瘤进展和转移,但可保留膀胱。膀胱切除也许提供了最好的治疗方案,但膀胱切除仍会复发且具有手术风险,且被认为是过度治疗。此文从哲学角度来探讨T1G3膀胱癌的治疗方法,以便为临床实践和进一步的研究提供思路。  相似文献   
122.
Children referred with specific reading dysfunction were subtyped as accuracy disabled or rate disabled according to criteria developed from an information processing model of reading skill. Multiple measures of oral and written language development were compared for two subtyped samples matched on age, sex, and IQ. The two samples were comparable in reading fluency, reading comprehension, word knowledge, and word retrieval functions. Accuracy disabled readers demonstrated inferior decoding and spelling skills. The accuracy disabled sample proved deficient in their understanding of oral language structure and in their ability to associate unfamiliar pseudowords and novel symbols in a task designed to simulate some of the learning involved in initial reading acquisition. It was suggested that these two samples of disabled readers may be best described with respect to their relative standing along a theoretical continuum of normal reading development.  相似文献   
123.
The responding of pigeons on a variable interval schedule of reinforcement was investigated in four experiments. In some conditions in each experiment reinforced keypecks were accompanied by a brief (0.5-sec) flash of the houselight. This procedure resulted in a low rate of response in comparison with that found in conditions when response-contingent light flashes occurred uncorrelated with reinforcement (Experiments 1 and 2) or when no light flash was presented (Experiment 3). Experiment 4 allowed a comparison between the effects of a signal accompanying the reinforced response and one accompanying the delivery of “free” food. Signaling the delivery of earned food produced a lower rate of response than did signaling the delivery of free food. The role of stimulus-reinforcer and response-reinforcer associations in producing these effects is discussed.  相似文献   
124.
125.
This paper distinguishes two interpretations of G. E. Moore's principle of organic unities, which says that the intrinsic value of a whole need not equal the sum of the intrinsic values its parts would have outside it. A holistic interpretation, which was Moore's own, says that parts retain their values when they enter a whole but that there can be an additional value in the whole as a whole that must be added to them. The conditionality interpretation, which has been defended by Korsgaard, says that parts can change their values when they enter wholes, so no additional value is needed. The paper shows that the two interpretations, which differ on such apparently important issues as the nature of intrinsic value, can always yield the same conclusions about the overall value in a state of affairs, so there is in that sense nothing to choose between them. At the same time, though, the differences between the interpretations make sometimes one and sometimes the other more appropriate for expressing a given evaluative view. In this last connection the paper considers views about beauty, posthumous achievement, vices of disproportion, deserved and compassionate pain, and undeserved and malicious pleasure.  相似文献   
126.
In three experiments analyzing determinants of the easy-to-hard effect, pigeons acquired a hard discrimination after training on other problems. Intradimensional pretraining resulted in immediate transfer to the hard discrimination. Extradimensional pretraining consistently did not produce immediate transfer but did facilitate learning rate. In Experiment 1, the compounding of cues from an easy extradimentsional discrimination with those from the hard discrimination resulted in the former overshadowing the latter. When different types of extradimensional discriminations were introduced in Experiments 2 and 3, the degree of transfer was not proportional to the similarity in incidental background cues across problems. The findings indicate that in the easy-to-hard effect: (a) intra- and extradimensional mechanisms jointly contribute to the development of stimulus control, (b) intradimensional transfer is more consistent with the gradient-interaction model than the selective attention model, and (c) extradimensional transfer is better accounted for by the construct of general attentiveness rather than by the neutralization of background cues.  相似文献   
127.
Subjects were given a preliminary problem solving task of either short or long duration, and were told that they could shorten the duration of aversive noise bursts by correctly solving the problems. They were then given false feedback that they had done either well or poorly on the problems. Two groups of failing subjects were given information designed to lead them to attribute failure to either lack of ability or a difficult task. Two additional groups received “success” or “failure” feedback without any attributional cues. Failure-induced stress was reported to be greater under short duration conditions than under long duration conditions, and increased to the extent that subjects were led to believe they were personally responsible for failure. Following the preliminary failure period, task performance in the same situation and task performance and persistence in a different situation were assessed. In each case, performance and persistence decreased (a) following short-duration failure when subjects were led to attribute failure to a difficult task, and (b) following long-duration failure when subjects were led to attribute failure to lack of ability. These results are discussed within a framework that emphasizes the role of casual attributions in mediating the effects of failure.  相似文献   
128.
Observing behavior and short-term recognition were studied in a training and test design. Preschoolers matched pictures from memory with training of a selective attending strategy or placebo practice. Both groups were then tested for retention of the strategies attained during training. For one-third of the subjects in each condition the relevant portions of the stimuli were made perceptually salient, for another third the irrelevant portions were salient, and for the rest no portions were salient. Strategy training enhanced relevant observing behavior and facilitated recognition accuracy in both training and test. The salient irrelevant cues interfered in training for the Placebo subjects. A second study examined the effect of three components of the strategy training procedure; verbal instructions, modeling, and fading. Verbal instructions, and to a lesser extent, modeling and fading, enhanced relevant observing behavior in both training and test but facilitated recognition accuracy only in training.  相似文献   
129.
Fifty third- and fourth-grade children, assigned to groups varying in Amount (1 or 2 sessions) and Type (cumulative-cluster or cluster) of strategy training or to a control condition, participated in three free recall sessions, two training sessions with blocked lists of common words and a maintenance session with a 50-states list blocked by geographical regions. During strategy training and maintenance, the cumulative-cluster groups recalled more than the cluster and control groups. Amount of training significantly influenced degree of strategy maintenance, but only in the cumulative-cluster strategy. Strategy form was highly correlated with recall in the cumulative-cluster condition, while total study time (effort) was related to recall only in conditions where strategy instructions were not given. The form of the strategy during training predicted transfer form and recall. 100% of the children who received extended training and demonstrated good strategy form during acquisition sessions successfully transferred the strategy to the geography task.  相似文献   
130.
Some previous literature suggests that young children perceive in an integral, holistic fashion stimuli that older children perceive in a separable, dimensionalized mode. A prediction from a strong form of this position is that younger children actually may perform more rapidly a speeded classification task that requires “condensation” than a task that requires “filtering” (if the similarity relations among the wholes favor the former task). Older children should be able to take advantage of the simple unidimensional basis of the filtering task and thus accomplish it much more rapidly than the condensation task. The results are only partially in accord with the predictions. Kindergarteners (5 years of age), on size-and-brightness stimuli, show no speed advantage on either task, while second (8 years) and fifth (11 years) graders clearly show more rapid filtering. Therefore, the developmental hypothesis is in need of some revision and elaboration. Some stimuli are less separable for younger than for older children, but even five year olds can access their dimensional structure under some conditions.  相似文献   
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