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21.
A new method for measuring tibial torsion is described which can be applied to both ultrasound (US) and computed tomography (CT). The method has been validated in dry tibiae by comparison with direct measurements and with Jend's established CT method. In clinical practice a good statistical level of agreement has been demonstrated between the values obtained from US and CT scans. Both compared well with values obtained using Jend's CT technique. The use of US avoids exposure to radiation and is therefore suited to studying young subjects and controls and making repeat measurements.  相似文献   
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OBJECTIVES: This article examines the differences found between clientele with severe mental health problems and their key health workers in terms of assessing service users' needs in 6 Quebec service areas. METHOD: We questioned 165 pairs of users and staff, using the Camberwell Assessment of Needs questionnaire. The profile of serious and overall problems encountered by clientele from each of the sites was compared. RESULTS: The sites with the greatest degree of user-staff agreement in identifying problems were also the ones where users considered that local services best met their needs. CONCLUSIONS: The study demonstrated that, in needs assessment, major differences exist between the perceptions of users and their key workers in the various sites. These differences can be explained in part by users' individual characteristics, by types of needs, by local particularities, and by service use.  相似文献   
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1. Thiophene and its two monobromo derivatives were administered to rats and the amounts of thioether excreted in urine were measured by an assay based on Ellman's reagent. This assay, which involves extraction and hydrolysis, was validated by determining extraction and hydrolysis efficiencies for several authentic thioethers including N-acetyl-S-(2-thienyl)-L-cysteine, a previously reported metabolite of thiophene and 2-bromothiophene. 2. The thioethers present in urine of animals dosed with thiophenes have been examined chromatographically. Contrary to previous reports, the present work indicates that S-substituted, N-acetyl-L-cysteines (mercapturic acids) are not important thioether metabolites of thiophene in rats, and the small quantity of such compounds formed does not include either of the two simple S-thienyl derivatives. 3. The two monobromo thiophenes form higher proportions of thioethers than does thiophene, and one of these thioethers, arising from 3-bromothiophene, was identified, chromatographically, as N-acetyl-S-(3-thienyl)-L-cysteine.  相似文献   
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The role of 3D CT in the assessment of acetabular fractures.   总被引:10,自引:0,他引:10  
A total of 16 patients with acetabular fractures were evaluated by plain radiography, axial computed tomography (CT) and three dimensional (3D) CT. It was possible to classify the fracture type in each case from the plain radiographs alone. Axial CT gave additional detail in certain areas, notably the region of the teardrop, the obturator foramen and the acetabular roof. Intra-articular and impacted roof fragments and associated soft tissue injuries were also shown. 3D CT provided the best and most easily interpreted overall assessment of the fractures. In addition to projections equivalent to the plain radiographs, two other views were of particular clinical value in demonstrating surgically inaccessible areas, namely the view of the pelvis from above and the view of the inner aspect of the fractured hemipelvis. However, fracture lines demonstrated on plain radiographs and axial CT were not always apparent on the 3D CT scans. Although 3D CT is a valuable addition to the imaging of acetabular fractures, it is not a substitute for good quality plain radiography and analysis of the axial CT images.  相似文献   
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OBJECTIVE: The aim of this study was to determine if there is a significant correlation between the in vivo presence of periapical radiolucency and ex vivo apical dye penetration on the same human teeth. STUDY DESIGN: Eighty-four endodontically filled teeth that were scheduled for extraction were classified into 2 groups according to the presence or absence of a periapical radiolucency and further divided into 2 subgroups according to the quality of the root canal filling. After extraction, the apical filling was evaluated by a dye penetration method. RESULTS: The dye extraction evaluation showed no correlation between apical dye penetration and the presence of a periapical radiolucency (not significant), but a statistically significant correlation with the quality of the root canal filling (P = .03). CONCLUSION: The results of the dye penetration study were correlated to the quality of the root canal filling but had no predictive value for the development of periapical radiolucency.  相似文献   
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BACKGROUND CONTEXT: Symptomatic spinal epidural lipomatosis (SEL), a rare cause of spinal cord compression, has most often been associated with exogenous steroid use. PURPOSE: Identify four associations with SEL, correlate the associated groups with level of disease and compare treatment with outcome data in these groups. STUDY DESIGN/SETTING: Case reports of three patients and analysis of 104 cases from the literature. PATIENT SAMPLE: Three patients from the senior author's practice. OUTCOME MEASURES: Not applicable. METHODS: The authors report three new cases of SEL not associated with steroid use. They review all available English literature and present a table of all 104 reported cases. RESULTS: The clinical course of three new patients is reported. CONCLUSIONS: Associated conditions are exogenous steroid use, obesity, endogenous steroid excess, and some remain idiopathic. Although SEL is a rare condition, our review of the literature reveals many more reported cases than previously thought. With increased awareness of this condition and improved imaging techniques, further studies of this disease should be undertaken.  相似文献   
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