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891.
We offer a framework for understanding how color operates to improve visual memory for images of the natural environment, and we present an extensive data set that quantifies the contribution of color in the encoding and recognition phases. Using a continuous recognition task with colored and monochrome gray-scale images of natural scenes at short exposure durations, we found that color enhances recognition memory by conferring an advantage during encoding and by strengthening the encoding-specificity effect. Furthermore, because the pattern of performance was similar at all exposure durations, and because form and color are processed in different areas of cortex, the results imply that color must be bound as an integral part of the representation at the earliest stages of processing.  相似文献   
892.
People with autism and Asperger syndrome are anecdotally said to be hypersensitive to touch. In two experiments, we measured tactile thresholds and suprathreshold tactile sensitivity in a group of adults with Asperger syndrome. In the first experiment, tactile perceptual thresholds were measured. Two frequencies of vibrotactile stimulation were used: 30 and 200 Hz. The results demonstrated significantly lower tactile perceptual thresholds in the Asperger group at 200 Hz but not at 30 Hz, thus confirming tactile hypersensitivity but only for one class of stimulus. A second experiment investigated whether self-produced movement affected the perception of touch in a group of adults with Asperger syndrome. A suprathreshold tactile stimulus was produced either by the participant (self-produced condition) or by the experimenter (externally produced condition) and participants were asked to rate the perception of the tactile stimulation. The results demonstrated that, while both Asperger and control groups rated self-produced touch as less tickly than external touch, the Asperger group rated both types of tactile stimulus as significantly more tickly and intense than did the control group. This experiment confirms the finding of tactile hypersensitivity, but shows that the perceptual consequences of self-produced touch are attenuated in the normal way in people with Asperger syndrome. An abnormality in this process cannot therefore account for their tactile hypersensitivity.  相似文献   
893.
This study compared adults (Homo sapiens), young children (Homo sapiens), and adult tamarins (Saguinus oedipus) while they discriminated global and local properties of stimuli. Subjects were trained to discriminate a circle made of circle elements from a square made of square elements and were tested with circles made of squares and squares made of circles. Adult humans showed a global bias in testing that was unaffected by the density of the elements in the stimuli. Children showed a global bias with dense displays but discriminated by both local and global properties with sparse displays. Adult tamarins' biases matched those of the children. The striking similarity between the perceptual processing of adult monkeys and humans diagnosed with autism and the difference between this and normatively developing human perception is discussed.  相似文献   
894.
In 2 experiments, the authors investigated whether age-related differences exist in metacomprehension by evaluating predictions based on the ease-of-processing (EOP) hypothesis. According to this hypothesis, judgments of how well a text has been learned are based on how easily each text was processed; easier processing results in higher judgments. Participants read either sentence pairs or longer texts and judged their learning of each immediately afterward. Although an age-related difference in the use of processing ease in judgments was observed with sentence pairs, for longer texts older and younger adults' judgments were similarly related to processing ease. In both experiments, age equivalence was also evident in the accuracy of the judgments at predicting performance on the criterion test. The overall pattern of results suggests that judging text learning remains largely intact with aging.  相似文献   
895.
The development of highly active antiretroviral therapy (HAART) has resulted in dramatic decreases in morbidity and mortality for HIV-infected individuals. Because the long-term efficacy of HAART is dependent on near perfect adherence, many providers offer services to support adherence, including education, regimen review, counseling, and reminder tools. Little is known regarding the utilization or efficacy of these services. In this paper, we report on data collected during 32 open-ended interviews conducted with individuals receiving services through the New York State Treatment Adherence Demonstration Project. Participants in the project reported deriving benefits from a broad range of project activities. Educational efforts helped clients to recognize HIV as a manageable, rather than terminal, illness. Information and tools focused on specific regimens provided clients with concrete knowledge and skills. Effective communication with medical providers and pharmacists was facilitated by adherence staff who proactively advocated for client needs. Program-based social support was particularly valuable for many participants, helping them to retain needed motivation and strength. Educational, practical, and supportive services were all considered valuable to clients participating in adherence support programs. A mix of services may best meet the range of needs found among persons taking HAART.  相似文献   
896.
The nicotinic antagonist mecamylamine has been widely shown to cause cognitive impairment. However, these effects are mainly seen with high doses. There have been scattered findings that low doses of mecamylamine can have the opposite effect. This may be due to opposite effects of low doses of mecamylamine. In the current study, an extensive dose-effect function of mecamylamine was characterized in the low-dose range. Adult female Sprague-Dawley rats were trained on a repeated acquisition procedure on an automated 8-arm radial maze. Three of the eight arms were designated as correct for any particular session. Five trials per session were run. The number of errors per trial to find the three correct arms was determined. The rats were trained on the repeated acquisition procedure for at least 18 sessions at which time they showed reliable learning each session. Then, the effect of low doses of mecamylamine between 0 and 1 mg/kg were assessed in a repeated measures counterbalanced design. This dose range of mecamylamine did not affect performance on the first trial when the rats were na?ve to the array to be learned. On trials 2-5 a significant (p<.025) quadratic dose-effect function was seen over this dose range. The most substantial effect was seen with 0.125 mg/kg of mecamylamine, which caused a significant (p<.05) improvement relative to the saline control condition. The effect diminished with increasing mecamylamine doses and with the 1 mg/kg dose choice accuracy was back to control levels. This study showed that low doses of mecamylamine can effectively improve learning. A U-shaped dose-effect curve was documented. This suggests possible low-dose nicotinic antagonist lines of treatment for cognitive impairment.  相似文献   
897.
The goal of this study was to determine whether genetic counseling or psychosocial group counseling provided to Ashkenazi women can reduce breast cancer worry, cancer risk perception, and interest in having genetic testing. Women (N=211) were randomized to receive individual genetic risk counseling, to receive a group psychosocial group counseling, or to serve as a control group. The authors found that both counseling methods reduced cancer worry, lowered perceptions of breast cancer risk, and decreased interest in having genetic testing. Counseling can help women gain a more accurate perception of their risk, expose them to the benefits and limitations of genetic testing, and reduce their worry about cancer.  相似文献   
898.
Online game addiction is a new mental disorder. This disorder is difficult to describe because of its comprehensive nature. Many online game players have problems controlling their playing time. They cannot stop playing a game that they enjoy. This research surveyed the past literature on "flow" and time disorder theory. A time distortion experiment was conducted. This research invited 64 children, teenagers, and young adults to investigate player skill and playing time effects on online game break-off. The playing experience and degree of time distortion were measured and analyzed. The results showed that both novice and expert online game players were subject to time distortion. The participants had difficulty breaking off from the game without intrusion by others in the real world. This research also suggests eight questions for self-evaluation for online game addiction.  相似文献   
899.
900.
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