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71.
OBJECTIVES: Measurement of cortical thickness and subjective assessment of cortical porosity on panoramic radiographs are methods previously reported for diagnosing osteoporosis. The aims of this study were to determine the relative efficacy of the mandibular cortical index and cortical width in detecting osteoporosis, both alone and in combination, and to determine the optimal cortical width threshold for referral for additional osteoporosis investigation. STUDY DESIGN: Six hundred seventy-one postmenopausal women 45 to 70 years of age were recruited for this study. They received dual energy x-ray absorptiometry (DXA) scans of the left hip and lumbar spine (L1 to L4), and dental panoramic radiographic examinations of the teeth and jaws. Three observers separately assessed the mandibular cortical width and porosity in the mental foramen region of the mandible. Cortical width was corrected for magnification errors. Chi-squared automatic interaction detection analysis (CHAID) software was used (SPSS AnswerTree, version 3.1, SPSS Inc., Chicago, IL). RESULTS: Chi-squared automatic interaction detection analysis showed that the cortical porosity was a poorer predictor of osteoporosis than mandibular cortical width. For the 3 observers, a mandibular cortical width of <3 mm provided diagnostic odds ratios of 6.51, 6.09, and 8.04. The test is therefore only recommended in triage screening of individuals by using radiographs made for purposes other than osteoporosis. CONCLUSION: When evaluating panoramic radiographs, only those patients with the thinnest mandibular cortices (i.e., <3 mm) should be referred for further osteoporosis investigation.  相似文献   
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This study builds on our earlier investigation (see Ganesalingam et al., 2006). We showed previously that children with moderate to severe traumatic brain injuries (TBI) had poorer self-regulation and social and behavioral functioning than their uninjured peers and that self-regulation predicted significant variance in parent- and teacher-rated social and behavioral outcomes, regardless of the presence or absence of TBI. In this study, we examine self-regulation as a mediator of the relationship between TBI and the outcomes. Participants included 65 children with moderate to severe TBI and 65 children without TBI matched for age and gender. Participants were between 6 and 11 years of age. Children completed an assessment of cognitive, emotional, and behavioral self-regulation, and social and behavioral functioning. Mediation was assessed using a bootstrapping approach (a relatively novel statistical method for assessing specific indirect effects in models with multiple mediators). Analyses indicated that, after controlling for socioeconomic status (SES), aspects of self-regulation accounted for individual variation in the outcomes, and acted as a significant mediator of the effects of TBI on the outcomes. Self-regulatory deficits may reflect the relative vulnerability of the prefrontal cortex to TBI and may help account for post-injury difficulties in social and behavioral functioning.  相似文献   
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Various patterns of ankle fractures that are not accounted for by common classification systems have been the subject of case reports. The first difficulty with these variant patterns is recognizing all associated pathology, followed by the successful application of stable fixation. The purpose of this study was to describe the common morphologic features and ligamentous injuries of a unique variant fracture pattern, as well as the surgical treatment technique and the short-term functional and radiographic outcomes. Of 121 consecutive unstable ankle fractures over a 2-year period, 7 patients were found to have a similar constellation of injuries around the ankle. A vertical shear fracture of the posteromedial tibial rim was the main feature. Six of the 7 also had a fracture of the posterior malleolus. On magnetic resonance imaging, the deltoid and posterior tibiofibular ligaments were intact in all cases. Fractures were treated with open anatomic reduction of the posteromedial and posterior fragments with antiglide plate fixation. All fractures healed at 2 months without loss of reduction, fixation failure, or surgical complications. The average American Academy of Orthopaedic Surgeons lower extremity score was 79 at an average of 8 months' follow-up. The common radiographic and morphologic features associated with this posteromedial fracture indicate that it likely occurs through a common mechanism that involves hyperplantarflexion. The characteristics of this fracture pattern have not been fully described previously, but this ankle fracture variant may occur in up to 6% of cases. Unstable ankle fractures should be evaluated carefully for evidence of posteromedial involvement so appropriate treatment may proceed.  相似文献   
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Laparoscopic cholecystectomy: let us control the virus   总被引:1,自引:1,他引:0  
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A series of 206 necropsies in Western Australia (WA) have had routine counts made of asbestos bodies in samples of lung tissue using conventional light microscopy. Thirty-two cases had worked in the asbestos industry at Wittenoom, WA and (log) counts of asbestos bodies in their lung tissue correlated well with estimates of their (log) cumulative airborne exposure to crocidolite fibers (r = 0.60). There was no association between the number of asbestos bodies and time since exposure to asbestos ceased. In subjects without known exposure to asbestos, there was a weak but nonsignificant increase in number of asbestos bodies with increasing age, with 26% of cases having no asbestos bodies present. It is concluded that the relatively simple technique of light microscopy for counting of asbestos bodies in lung tissue provides a reliable indication of the level of past occupational exposure to crocidolite in subjects whose exposure has been only to crocidolite. This could be extremely useful in follow-up studies of cohorts that lack reliable measures of airborne exposure to crocidolite asbestos.  相似文献   
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