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Brian F O'Donnell Marcia A Wilt Ann Marie Hake Julie C Stout Sandra C Kirkwood Tatiana Foroud 《Movement disorders》2003,18(9):1027-1034
Disturbances of visual cognition, visuomotor performance, and visual memory have been described frequently in Huntington's disease (HD). Early stage visual abnormalities could contribute to these deficits. We evaluated visual processing in 20 control subjects who were non-gene carriers at risk for HD, nine presymptomatic gene-positive subjects, and eight subjects with a recent diagnosis of Huntington's disease. Visual perceptual tests of contrast sensitivity and motion discrimination were used to probe early stage visual processing. Extraocular movements were evaluated in a neurologic examination, and the Digit Symbol test was used to test visual motor performance. Contrast sensitivity did not differ among the three groups. Motion discrimination was impaired in HD subjects but not in the presymptomatic gene carriers when compared to gene noncarriers. Among gene carriers, impaired motion discrimination performance was associated with poorer Digit Symbol performance and extraocular abnormalities. These findings suggest that the early stages of HD are associated with disturbances of motion perception as well as disruptions of visual motor and ocular motor performance. 相似文献
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Primary care referrals for lumbar spine radiography: diagnostic yield and clinical guidelines. 下载免费PDF全文
William Hollingworth Christopher J Todd Hugh King Tony Males Adrian K Dixon Kanti R Karia Ann Louise Kinmonth 《The British journal of general practice》2002,52(479):475-480
BACKGROUND: Primary care requests for radiographs of the lumbar spine have come under increasing scrutiny. Guidelines aiming to reduce unnecessary radiographs by limiting referrals to patients at high risk of serious disease have been widely distributed. Trial evidence suggests that guidelines can reduce radiography referrals. It is not clear whether this reduction has been achieved in routine practice. AIM: This study, using routine data, was conducted to measure trends in pnmary care referrals for lumbar spine radiography at two hospitals between 1994 and 1999. DESIGN OF STUDY: Analysis of primary care requests for lumbar spine radiography from computerised records. SETTING: Addenbrooke's Hospital, Cambridge (1 July 1994 to 30 June 1999), and Ipswich General Hospital (1 July 1995 to 30 June 1999), United Kingdom. METHOD: All primary care requests for lumbar radiography were identified electronically from computerised information systems. A random sample of 2100 radiography reports were classified according to clinical importance. These classifications were used to examine whether the proportion of radiographs demonstrating potentially more serious findings had increased between 1994 and 1999. RESULTS: There was no evidence that primary care referrals for radiography of the lumbar spine had decreased between 1994 and 1999 at either hospital. General practitioners did not progressively refer more high-risk patients for lumbar radiography. Only a small proportion of patients had important radiographic findings that might warrant specialist referral or specific therapy. CONCLUSION: The implementation of diagnostic guidelines offers much to the NHS. However in these two hospitals, the reduction in radiograph utilisation evident in trials was not achieved. Guideline development is a resource intensive process; distribution must be supported by more effective implementation strategies. 相似文献
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The spontaneous language sample forms an important part of the language evaluation protocol (M. Dunn, J. Flax, M. Sliwinski, and D. Aram, 1996; J. L. Evans and H. K. Craig, 1992; L. E. Evans and J. Miller, 1999) because of the limitations of standardized language tests and their unavailability in certain languages, such as Afrikaans. This study examined 3 methods of language elicitation, namely conversation (CV), freeplay (FP), and story generation (SG), on the following 5 measures to determine which method is best for clinical practice: number of utterances, variety of syntactic structures, mean length of the utterance (MLU), number of syntactic errors, and proportion of complex syntactic utterances as elicited from ten 5-year-old, Afrikaans-speaking boys. FP elicited significantly more utterances than did SG but elicited a smaller proportion of complex syntactic structures than did CV and SG. Furthermore, SG elicited longer utterances than did CV or FP. It is recommended that SG be used in clinical practice with 5-year-olds if the clinician wishes to observe maximum behavior. Where typical behavior is to be evaluated, the clinician can select a language elicitation method that best suits the client's personality and communication style, bearing in mind that FP does elicit a larger language sample. 相似文献
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The purpose of this study was to examine motor learning and retention given extensive practice in two fundamentally different movement sequences. One sequence was a memory-driven task (performing a series of whole body positions from memory) and the other a context-driven task (buttoning). Practice took place over 3 weeks, with performance measured weekly; retention was measured weekly for 3 weeks after practice. There were 7 people with Parkinson's disease (PD) and 7 age-matched neurologically healthy people who participated in this study. Both groups improved performance on both tasks with practice, with the majority of the change for the PD group occurring between 1 and 2 weeks of practice. Although those with PD did not necessarily perform as well as age-matched controls, they learned both sequences in a manner similar to age-matched controls, and exhibited retention across the 3-week retention interval. If people with PD are given sufficient practice they can learn and retain both memory-based and context-driven movement sequences as well as age-matched controls. The results provide support for maintaining physical activity and for intervention through movement therapy. 相似文献
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Ann Silversides 《Canadian Medical Association journal》2006,175(4):342
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浅析《内经》之闭经证治 总被引:1,自引:1,他引:0
收集了《内经》有关闭经方面的相关阐述从而探讨闭经的病因病机、诊断与治疗,并详细记述了《内经》对血滞经闭和血枯经闭这两类型经闭的不同治疗法度。 相似文献
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