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861.
Broome J 《Ethics》1984,95(1):38-55
This article considers what justification can be found for selecting randomly and in what circumstances it applies, including that of selecting patients to be treated by a scarce medical procedure. The author demonstrates that balancing the merits of fairness, common good, equal rights, and equal chance as they apply in various situations frequently leads to the conclusion that random selection may not be the most appropriate mode of selection. Broome acknowledges that, in the end, we may be forced to conclude that the only merit of random selection is the political one of guarding against partiality and oppression.  相似文献   
862.
863.
A sentence often contains two components: a topic, which refers to a nonlinguistic object whose existence is presupposed; and a comment, which asserts some thought about this object. In addition, a sentence will often repeat (or refer back to) information that was expressed earlier in a text or conversation. The purpose of this article is to propose a single theoretical framework to describe the mechanisms that relate a sentence to its nonlinguistic environment as well as those that relate a sentence to its linguistic context. The theory developed in this article suggests that sentences can strongly influence the representation of visible nonlinguistic events and that this representation is sensitive to the distinction between presupposed and asserted information. To evaluate this theory, a sentence-picture verification priming task was developed. In this task, subjects were presented with pairs of sentence-picture displays, and were asked to verify whether or not the sentence in each display correctly applied to an accompanying picture. The relationship between pairs of sentence-picture displays was varied systematically. Across five experiments, three hypotheses were supported: (a) The processes which evaluate presupposed information and the processes which evaluate asserted information are differentially affected by nonlinguistic factors, (b) only those aspects of the picture which are referred to by the sentence are encoded for future use, and (c) coherence between successive sentences is in part a function of the referential continuity of the presupposed information.  相似文献   
864.
The relationship between reinforcer amount and daytime smoking reduction in smokers offered money for reduced afternoon breath carbon monoxide (CO) levels was examined. Twenty-three hired regular smokers with average baseline CO levels of about 30 ppm were exposed in random order to five sliding scale payment schedules that changed daily or weekly. Money was available for afternoon CO readings between 0 and 21 ppm with pay amount inversely related to the absolute CO reading obtained. Maximum pay amount for readings below 7 ppm varied among $0, $1.50, $3, $6, and $12 per day. Contingent reinforcement promoted CO and daytime cigarette reduction within individuals with the amount of behavior change related to the amount of payment available. Average CO levels decreased from 30 to 15 ppm as a function of pay amount whereas self-reported daytime cigarettes decreased from 12 to 5 per day. Average minutes of cigarette abstinence prior to the afternoon study contact increased from 62 to 319 minutes as a function of pay amount, whereas the percentage of available money earned increased from 22% to 48%. Nontargeted evening cigarette use also decreased during periods of daytime smoking reduction. The orderly effects of this contingent reinforcement intervention on daytime smoking of regular smoker volunteers suggest that this is a sensitive model for continued evaluation of factors that influence smoking reduction and cessation.  相似文献   
865.
The effects of a graduated prompting treatment procedure were analyzed in three phases of an experiment on the training and generalization of reaching-grasp responding in 2- to 4-year-old blind, severely or profoundly retarded children. In Phase 1, we used a multiple-baseline across-subjects design to investigate the effectiveness of the treatment on midline reach-grasp responding. In Phase 2, we used a reversal design to investigate the effects of repeated implementations and withdrawals of the treatment. In both phases, generalization to right and left positions was measured. In Phase 3, in a multiple-baseline across-responses design, the treatment was implemented in right and left positions. Also in Phase 3, shift of stimulus control from toy-sound to verbal instructions was measured. The results showed that (a) the graduated prompting procedure was effective in training reach-grasp responding in all three children; (b) for one child, the effects were durable over repeated applications of the treatment procedure, but were not maintained during withdrawals; (c) for another child, the treatment procedure was effective in teaching reach-grasp responding in all three positions; and (d) for the same child, training of reach-grasp responding generalized to toys presented without sound, given only the verbal instruction.  相似文献   
866.
867.
868.
We examined the effect of reducing the interval between a patient's call for an appointment and the appointment itself. In Experiment 1, patients calling a family planning unit of a public health department were assigned appointments within either 1 or 3 weeks of their call. Data on patient “shows” and “no-shows” were recorded weekly for 6 weeks. Show rates for those in the 1-week appointment group were significantly higher than those in the 3-week group. In Experiment 2, patients were assigned to appointment dates either the next operating clinic day (next-day group) or 2 weeks from the call date (2-week group). Show rates for those in the next-day group were significantly better than show rates for patients in the 2-week group. Clinic productivity, time spent with patients, and consumer satisfaction were also assessed. Implications for appointment scheduling are discussed.  相似文献   
869.
In two longitudinal studies, infants were trained at 12 and 18 months to find an object hidden in one of two identical wells in a Plexiglas box. On the test trial, normal access was blocked and infants were either guided by their mother or allowed to move on their own to another opening on the opposite side. In Experiment 1 significantly more correct responding occurred after active movement than after passive at 12 months, with correct responding related to high visual tracking. In contrast, at 18 months correct search without tracking predominated among both movement conditions. A difference between the conditions in the position of the mother on the test trial was ruled out as a contributor to performance on the basis of data from Experiment 2. When opaque sides were inserted to prevent tracking in Experiment 3, active movement no longer facilitated correct search at 12 months, thus indicating that the tracking and not the active movement per se was the critical factor.  相似文献   
870.
Nursery schoolers and first- and third-graders participated in an interview which assessed recall, comprehension, and perceived importance of three sources of self-knowledge: social feedback, self-observation, and social comparison. For recall measures, these sources were embedded in stories about a child making a self-discovery. Recall of all three sources improved with grade level, and feedback was the best remembered self-validational process. Comprehension was defined as the ability to identify the sources as depicted in line drawings, and it, too, increased with grade level. All three sources were well understood by older children, but preschoolers had difficulty with the concept of social comparison. Ratings of importance, also assessed using line drawings, were independent of grade level. When selecting their own “very best” source of self-knowledge, children cited self-observation most frequently. A supplementary sample of preschoolers nominated the best source of self-knowledge for other children rather than for themselves; under these instructions, feedback from others emerged as the preferred source.  相似文献   
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