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251.
2003年诺贝尔医学奖给科学界的多重启示(上)   总被引:1,自引:0,他引:1  
2003年诺贝尔医学奖授予了两位美英物理学家,劳特布尔和曼斯菲尔德,表彰他们在磁共振成像方面的发现.这些发现导致现代磁共振技术的开发,这一技术标志着医学诊断学和科学研究中的一项突破.该项发现建筑在核磁和核磁共振现象被发现的基础之上.核磁现象的发现及其应用导致了1943、1944和1952年诺贝尔物理学奖的获得.核磁共振现象的发现及其应用导致了1991年和2002年诺贝尔化学奖的获得.这意味着,2003年诺贝尔医学奖是该系列发现中第六个诺贝尔科学奖.  相似文献   
252.
Self-help and psychoeducation have been identified as effective methods for delivering treatment, yet not everyone benefits from these brief interventions. Therefore it is clinically and economically useful to identify who is likely to require more intensive assistance. This paper develops a prognostic scale which predicts who will recover from panic attacks and who will require more assistance. Method: Random regression models were used to evaluate the relationship between predictive variables, baseline severity, and the rate of improvement in 117 people with DSMIV panic attacks who participated in a trial of a psycho-educational booklet, a self-help workbook, and brief group CBT over a 9-month period. ROC analysis was used to choose cut-off points on a scale made up of significant predictors. Results: Panic disorder and agoraphobia symptom measures were predicted by baseline social anxiety, and general mental health. There was no significant effect on the outcome for baseline depression or anxiety sensitivity. While general mental health (SF12 Mental Component scores) was predicted by the age at first panic attack, neuroticism, panic disorder and/or agoraphobia symptoms and a positive screen for alcohol use disorders. A prognostic scale based on simple additive scoring was equivalent to standard scores and significantly better than chance at predicting who would recover and who required face-to-face therapy. Conclusions: The prognostic scale may be used to guide the choice of psychoeducation, self-help or face-to-face therapy as the first step in stepped care.  相似文献   
253.
This study examined how young children change their strategies for size comparison. Twenty-two 5 and 6-year-old children were asked to compare the sizes of geometric figures and their strategies were observed once a week over three weeks. Half of the children were also asked to evaluate presented strategies for comparing geometric figures. It was found that over three weeks not only children who evaluated the strategies but also children who did not increased correct responses, the strategy of placing one figure on another, and the strategy of adjusting two figures by two dimensions. Although more children became aware of the effectiveness of those strategies, there was no relationship between the evaluation and use of strategies.  相似文献   
254.
The main objectives in the present study were to examine meaningful irrelevant speech and road traffic noise effects on episodic and semantic memory, and to evaluate whether gender differences in memory performance interact with noise. A total of 96 subjects, aged 13-14 years (n = 16 boys and 16 girls in each of three groups), were randomly assigned to a silent or two noise conditions. Noise effects found were restricted to impairments from meaningful irrelevant speech on recognition and cued recall of a text in episodic memory and of word comprehension in semantic memory. The obtained noise effect suggests that the meaning of the speech were processed semantically by the pupils, which reduced their ability to comprehend a text that also involved processing of meaning. Meaningful irrelevant speech was also assumed to cause a poorer access to the knowledge base in semantic memory. Girls outperformed boys in episodic and semantic memory materials, but these differences did not interact with noise.  相似文献   
255.
Justification for public funding of academic research is based on the linear model of technological advance first proposed by Francis Bacon. The model hypothesizes that government subsidized science generates new technology which creates new wealth. Mainstream economics supports Bacons model by arguing that academic research is a public good. The Bayh–Dole Act allows universities to privatize federally funded research and development (R&D) which is in direct conflict with the public good argument. Diminishing returns to university R&D, challenges to Bacons linear model and the labor exploitation of young scientists by research universities suggest that policy makers may want to reconsider the system for allocating federal R&D to universities and colleges.  相似文献   
256.
Learning about life and death in early childhood   总被引:2,自引:0,他引:2  
have argued that young children initially understand biological phenomena in terms of vitalism, a mode of construal in which "life" or "life-force" is the central causal-explanatory concept. This study investigated the development of vitalistic reasoning in young children's concepts of life, the human body and death. Sixty preschool children between the ages of 3 years, 7 months and 5 years, 11 months participated. All children were initially given structured interviews to assess their knowledge of (1) human body function and (2) death. From this sample 40 children in the Training group were taught about the human body and how it functions to maintain life. The Control group (n=20) received no training. All 60 children were subsequently reassessed on their knowledge of human body function and death. Results from the initial interviews indicated that young children who spontaneously appealed to vitalistic concepts in reasoning about human body functioning were also more sophisticated in their understanding of death. Results from the posttraining interviews showed that children readily learned to adopt a vitalistic approach to human body functioning, and that this learning coincided with significant development in their understanding of human body function, and of death. The overall pattern of results supports the claim that the acquisition of a vitalistic causal-explanatory framework serves to structure children's concepts and facilitates learning in the domain of biology.  相似文献   
257.
We evaluated the efficacy of a brief staff-training procedure to increase the use of graduated prompting by 2 certified nursing assistants (CNAs) while they helped to dress 3 persons with dementia in a seven-bed dementia care unit. The multiple baseline design across participants showed that CNAs dressed residents with minimal resident involvement during baseline observations. Following brief in-service training, CNAs provided graduated prompts and praise appropriately, suggesting that CNAs can promote active involvement in personal care routines by older adults with dementia.  相似文献   
258.
Delayed matching to complex, two-picture samples (e.g., cat-dog) may be improved when the samples occasion differential verbal behavior. In Experiment 1, individuals with mental retardation matched picture comparisons to identical single-picture samples or to two-picture samples, one of which was identical to a comparison. Accuracy scores were typically high on single-picture trials under both simultaneous and delayed matching conditions. Scores on two-picture trials were also high during the simultaneous condition but were lower during the delay condition. However, scores improved on delayed two-picture trials when each of the sample pictures was named aloud before comparison responding. Experiment 2 replicated these results with preschoolers with typical development and a youth with mental retardation. Sample naming also improved the preschoolers' matching when the samples were pairs of spoken names and the correct comparison picture matched one of the names. Collectively, the participants could produce the verbal behavior that might have improved performance, but typically did not do so unless the procedure required it. The success of the naming intervention recommends it for improving the observing and remembering of multiple elements of complex instructional stimuli.  相似文献   
259.
The role of locomotion in the acquisition and transfer of spatial knowledge was investigated in 144 five-, seven- and eleven-year-old children. Two experiments were conducted in the Kiel locomotor maze. In the first experiment, one group of children explored the spatial layout by walking through the maze, while another learned the maze by surveying the layout. In the second experiment, children were exposed to one of two orientation tests in the maze, one of which could be solved using "landmark orientation", the other only using a "relational place orientation". Children sitting by the side of the experimental chamber surveying the maze needed fewer trials to learn the spatial layout than children exploring the environment in the locomotion condition, but in the orientation test demanding the "relational place orientation" children who had explored the maze in the locomotion condition outperformed the children in the non-locomotion condition. Results are discussed in the context of cognitive mapping models.  相似文献   
260.
《孔丛子》六卷当出自“汉魏孔氏家学” ,其前三卷记孔子、子思言行 ,可能是辑先秦孔氏遗文。《孔丛子·记义》篇载有一大段孔子对《诗》的评论 ,其与上博简《孔子诗论》有着内在的关系 ,可以将它们视为同一个体系而相互参释和补充。《孔丛子》“诗论”与上博简《诗论》都反映了先秦儒家早期说诗的风格和内容 ,而与汉代形成的《诗序》传统不同。《孔丛子》“诗论”对朱熹的《诗经集传》有一定影响 ,在从汉代诗学向宋代诗学的转变过程中起了一定的作用。  相似文献   
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