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Stroke rehabilitation is an area of practice that many occupational therapists encounter during their career. The literature promotes a wide range of management techniques and support devices for people who have a stroke-affected upper limb, but little is known about the validity of those that occupational therapists actually use in practice. A questionnaire was sent to occupational therapists working in Queensland and northern New South Wales facilities (n = 35), in which adults with a stroke were likely to be treated. Eighteen respondents answered questions about the management techniques and support devices used in their facility, and their perception of the benefit of these devices in the reduction of hemiplegic shoulder pain. Results are discussed with reference to evidence-based practice and indicate an urgent need for the collation and dissemination of the best current evidence available for the management techniques and support devices used in this area, as well as further research to extend this evidence.  相似文献   
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The in-vitro inhibition constants (Ki) of 14 structural analogues of the potent 5-hydroxytryptamine (5-HT)-uptake inhibitor paroxetine were determined to assess the structure-affinity relationship of these derivatives. A goal of these studies was to determine those positions on paroxetine which could be derivatized without significantly decreasing the affinity of the drug for the binding site, so that radiolabels such as [18F]fluoroalkyl groups might be appended for future in-vivo imaging studies of the 5-HT uptake system. Using the methyl moiety as a steric probe for these studies, it was found that the rank order of potency of various methyl-substituted paroxetine analogues for inhibiting the binding of [3H]paroxetine to the 5-HT re-uptake site was: 4'-approximately equal to 3'-approximately equal to 2'- > 2'-approximately equal to 1- > 5'- > 6'-methyl. The in-vitro equipotent molar ratios (EPMR, Ki(analogue)/Ki(paroxetine)) of the analogues were determined, and the EPMRs of the 4'-, 3'-, and 2'-methyl derivatives were 1.9, 2.2 and 2.2, respectively. The 4'- and 2'-fluoromethyl and -fluoroethyl analogues were synthesized, and the EPMRs of the 4'- and 2'-fluoromethyl derivatives were determined to be 2.0 and 3.5, and those of the 4'- and 2'-fluoroethyl analogues were 5.2 and 6.2, respectively. The 2'-fluoromethyl analogue was unstable in aqueous solutions, and it is not a promising ligand for in-vivo studies.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Thymidine kinase (TK) exists in two forms, TK1 and TK2. TK levels and oestrogen receptor status (OR) were measured in tumours from 86 patients with operable breast cancer and the patients were monitored for recurrence over 24 months. During the monitored period, 13 patients showed recurrence. These patients also exhibited higher total TK levels per mg tumour (P < 0.01) and higher TK1 levels (P < 0.001) than those who did not show recurrence. TK1 levels relative to TK2 were significantly higher (P < 0.05) in OR-negative tumours (n = 29) than in OR-positive tumours (n = 57). OR-negative (n = 9) and OR-positive (n = 4) patients who recurred had significantly higher TK1 levels relative to TK2 than did those who not recur (n = 20 and n = 53, respectively). These preliminary results indicate that breast tumour TK levels may have value in determining prognosis.  相似文献   
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More than 700,000 people have a stroke each year in the United States. A diagnosis of stroke formerly elicited a nihilistic approach, but this has substantially changed in the last decade. Currently, time is brain, and it is important for all disciplines to work together to initiate acute stroke protocols in the emergency department and identify patients within the therapeutic time window for thrombolytic and neuroprotective therapies. Evolving protocols, management, and nursing care all have important implications during the acute phase of ischemic stroke. Patient and family education on risk reduction must also be addressed by the entire healthcare team.  相似文献   
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We assessed the feasibility and psychometric properties of two commonly used health status questionnaires in Parkinson's disease (PD): the generic Nottingham Health Profile (NHP) and the disease-specific 39-item Parkinson's disease Questionnaire (PDQ-39), from a cross-sectional postal survey of PD patients (N = 81), using traditional and Rasch measurement methodologies. Overall response rate was 88%. Both questionnaires were found feasible, although the NHP performed less well. The PDQ-39 had fewer floor effects and was better able to separate respondents into distinct groups than the NHP, whereas the latter exhibited less ambiguous dimensionality and better targeting of respondents with non-extreme scores. Reliability and validity indices were similar, and potential differential item functioning by age and gender groups was found for both questionnaires. PDQ-39 response alternatives indicated ambiguity. With few exceptions, questionnaire scales were unable to meet recommended standards fully. While preliminary, this study illustrates the need for thorough evaluation of outcome measures and has implications beyond the questionnaires used here. Although promising, both questionnaires warrant further developmental work and stronger support of measurement validity before they could be considered fully suitable for valid use in PD, in particular in earlier stages of the disease.  相似文献   
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A framework for evaluating image segmentation algorithms.   总被引:4,自引:0,他引:4  
The purpose of this paper is to describe a framework for evaluating image segmentation algorithms. Image segmentation consists of object recognition and delineation. For evaluating segmentation methods, three factors-precision (reliability), accuracy (validity), and efficiency (viability)-need to be considered for both recognition and delineation. To assess precision, we need to choose a figure of merit, repeat segmentation considering all sources of variation, and determine variations in figure of merit via statistical analysis. It is impossible usually to establish true segmentation. Hence, to assess accuracy, we need to choose a surrogate of true segmentation and proceed as for precision. In determining accuracy, it may be important to consider different 'landmark' areas of the structure to be segmented depending on the application. To assess efficiency, both the computational and the user time required for algorithm training and for algorithm execution should be measured and analyzed. Precision, accuracy, and efficiency factors have an influence on one another. It is difficult to improve one factor without affecting others. Segmentation methods must be compared based on all three factors, as illustrated in an example wherein two methods are compared in a particular application domain. The weight given to each factor depends on application.  相似文献   
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