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Dementia in Parkinson’s disease (PD/PDD) is a common complication with a prevalence of up to 50%, but the specific changes underlying the cognitive decline remain undefined. Neuronal degeneration resulting in the dysfunction of multiple subcortical neurochemical projection systems has been described along with Lewy body-type pathology in cortical and limbic regions. Advanced alpha-synuclein (αSyn) pathology is not necessarily sufficient for producing dementia and concomitant Alzheimer’s disease (AD) change has also been proposed as a possible substrate of PDD. A lack of consensus in the extant literature likely stems from clinical heterogeneity and variable reliability in clinical characterisation as well as other historical and methodological issues. The concurrent presence of abnormally deposited αSyn, amyloid-β and tau proteins in the PDD brain and the interaction of these molecules in a linked pathological cascade of AD and PD-related mechanisms may prove important in determining the underlying pathological process for the development of dementia in PD and this concept of combined pathologies awaits further investigation. 相似文献
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In a previous study, we reported the results of an early language screening program in which 306 children were screened using a parent-report questionnaire sent through the mail (Klee et al., 1998). A sample of the children screened were given clinical evaluations within a month of screening (n = 64) and again 1 year later (n = 36). Although the screening program correctly identified 91% of 2-year-olds with language delay, it produced a large number of over-referrals. In the present study we examine a revised screening criterion designed to reduce the number of false positives. The revised criterion generated fewer positive screens overall than the original and resulted in improved specificity (96% vs. 87%) and positive predictive value (77% vs. 51%), while maintaining the high sensitivity (91%) and negative predictive value (98%) of the original criterion. We also propose a screening score based on the new criterion, designed to inform the process of deciding which children to bring in for further evaluation. 相似文献
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Jane Pearce 《Psychiatry》2013,76(4):413-422
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