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Colette Gray 《Child Care in Practice》2004,10(1):39-47
In recent years a growing body of evidence has implicated deficits in the automaticity of fundamental facts such as word and number recognition in a range of disorders: including attention deficit hyperactivity disorder, dyslexia, apraxia and autism. Variously described as habits, fluency, chunking and over learning, automatic processes are best understood in terms of their distinctive properties. While typically identified as fast, parallel, attention-free processes, a commonly agreed definition of automaticity continues to elude theorists investigating this concept. Most theorists would, however, agree that since attentional resources are finite, automaticity of basic facts serves to free sufficient mental resources for a learner to focus their attention on the novel or more complex aspects of a task. Yet despite the importance of automaticity to the learner, the term remains largely unfamiliar to most educationalists and early years practitioners. In order to address this issue, the present paper seeks to review several influential theories of automaticity, to describe the problems associated with defining a process as automatic and to draw from relevant research to demonstrate how the early years environment can be organised to promote automaticity in the young learner. 相似文献
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Ute Bültmann Renée-Louise Franche Sheilah Hogg-Johnson Pierre Côté Hyunmi Lee Colette Severin Marjan Vidmar Nancy Carnide 《Quality of life research》2007,16(7):1167-1178
BACKGROUND: The purpose of this study was to describe the health status and work limitations in injured workers with musculoskeletal disorders at 1 month post-injury, stratified by return-to-work status, and to document their return-to-work trajectories 6 months post-injury. METHODS: A sample of 632 workers with a back or upper extremity musculoskeletal disorder, who filed a Workplace Safety and Insurance Board lost-time claim injury, participated in this prospective study. Participants were assessed at baseline (1 month post-injury) and at 6 months follow-up. RESULTS: One month post-injury, poor physical health, high levels of depressive symptoms and high work limitations are prevalent in workers, including in those with a sustained first return to work. Workers with a sustained first return to work report a better health status and fewer work limitations than those who experienced a recurrence of work absence or who never returned to work. Six months post-injury, the rate of recurrence of work absence in the trajectories of injured workers who have made at least one return to work attempt is high (38%), including the rate for workers with an initial sustained first return to work (27%). CONCLUSIONS: There are return-to-work status specific health outcomes in injured workers. A sustained first return to work is not equivalent to a complete recovery from musculoskeletal disorders. 相似文献
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High aggregate burden of somatic mtDNA point mutations in aging and Alzheimer's disease brain. 总被引:12,自引:0,他引:12
Michael T Lin David K Simon Colette H Ahn Lauren M Kim M Flint Beal 《Human molecular genetics》2002,11(2):133-145
The mitochondrial theory of aging proposes that mitochondrial DNA (mtDNA) accumulates mutations with age, and that these mutations contribute to physiological decline in aging and degenerative diseases. Although a great deal of indirect evidence supports this hypothesis, the aggregate burden of mtDNA mutations, particularly point mutations, has not been systematically quantified in aging or neurodegenerative disorders. Therefore, we directly assessed the aggregate burden of brain mtDNA point mutations in 17 subjects with Alzheimer's disease (AD), 10 elderly control subjects and 14 younger control subjects, using a PCR-cloning-sequencing strategy. We found that brain mtDNA from elderly subjects had a higher aggregate burden of mutations than brain mtDNA from younger subjects. The average aggregate mutational burden in elderly subjects was 2 x 10(-4) mutations/bp. The bulk of these mutations were individually rare point mutations, 60% of which changed an amino acid. Control experiments ensure that these results were not due to artifacts arising from PCR error, mistaken identification of nuclear pseudogenes or ex vivo oxidation. Cytochrome oxidase activity correlated negatively with increasing mutational burden. These findings significantly bolster the mitochondrial theory of aging. 相似文献
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George G. Browning 《Clinical otolaryngology》2005,30(6):546-546
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An allergic agranulocytosis induced by amidopyrine and triggered by noramidopyrine was studied. Leucoagglutinating and leucocytotoxic antibody, active only in the presence of the drug, was demonstrated. The antibody was stable, giving a titre from 1·34 to 1·62 and was present in the IgM (19S globulin) and in the IgG (7S globulin) serum fractions. The site of drug fixation was studied by use of iodoantipyrine labelled with 131I; a stable fixation was demonstrated on to the IgM and IgG globulins. Special emphasis is given to cross-reaction with compounds related to amidopyrine. 相似文献