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The effect of a newly developed patellar realignment brace was evaluated in 21 patellofemoral joints (19 patients) with patellar subluxation (13 joints with lateral subluxation and eight with medial subluxation) by using active-movement, loaded kinematic magnetic resonance (MR) imaging. Sixteen patellofemoral joints (76%) demonstrated a qualitative correction of or improvement in patellar subluxation (ie, centralization of the patella or a decrease in the displacement of the patella) after application of the brace. Four of the five “failures” occurred in patellofemoral joints that had patella alta and/or dysplastic bone anatomy. These results indicate that the patellar realignment brace was able to counteract patellar subluxation in the majority of patellofemoral joints studied, as shown by active-movement, loaded kinematic MR imaging. This brace appears to be useful for conservative treatment of patients with patellofemoral joint pain secondary to patellar malalignment and maltracking.  相似文献   
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Background/aim  Theoretical considerations support the combination of cryosurgery and topical imiquimod to treat basal cell carcinomas (BCC). The aim of the present study was to test the feasibility and efficacy of 'cryosurgery during continued imiquimod application' ('immunocryosurgery') to treat 'high-risk-for-recurrence' BCCs.
Methods  Thirteen patients with 21 biopsy-proven tumours (4 of 21 relapses after prior surgery) were included. After 2–5 weeks (median, 3) of daily 5% imiquimod cream application, the tumours were treated by liquid N2 cryosurgery (spray, two cycles, 10–20 s) and imiquimod was continued for additional 2–12 weeks (median, 4). The outcome after at least 18 months of follow-up (18–24 months) is currently reported.
Results  Nineteen of 21 tumours responded promptly to immunocryosurgery; two tumours required additional treatment cycles to clear. Thus, the clinical clearance rate was 100%. Only 1 of 21(5%) tumour relapsed after at least 18 months of follow-up (cumulative efficacy: 95%).
Conclusions  'Immunocryosurgery' is a promising non-surgical combination modality to treat 'high-risk-for-recurrence BCCs'. Initial evidence is suggestive of an at least additive effect of the two combined modalities. Further studies comparing immunocryosurgery directly with cryosurgery and imiquimod monotherapies will confirm the reported results.  相似文献   
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OBJECTIVES: Radiopacity is a desirable property for most intra-oral materials. There are established ISO and ANSI/ADA protocols for determining radiopacity using film-based radiography. However, these methods are not always followed by researchers. This study aims to adapt those procedures by using digital radiography, a simplified stepwedge, and examine the effects of target distance and exposure time choice. METHODS: One millimetre thick samples of three dental materials were prepared by placing the materials into a 1.00 mm thick washer sandwiched between two glass slides. The samples were digitally radiographed alongside a stepwedge of aluminum alloy 1100 with an X-ray unit at 70 kVp using five different target distance/exposure time combinations. For each combination, the grey scale values of various thicknesses of the stepwedge were converted into absorbencies and plotted against their thickness. These plots were then linearly regressed in order to correlate absorbance with a thickness of aluminum for each target distance/exposure time combination. The absorbencies of each sample were then converted into radiopacities using these correlations. RESULTS: The correlations between the absorbance of the stepwedge and its thickness were highly linear. This linearity allows the correlation to be accurately deduced from fewer data points than required by the ISO and ANSI/ADA protocols. Varying exposure time did not significantly affect the mean radiopacity measured at a target distance of 30 cm. Varying the target distance did not significantly affect the measured radiopacity as long as the samples were properly exposed. SIGNIFICANCE: A simplified, consistent digital method for determining radiopacity is presented.  相似文献   
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The retention of the post to the root of an endodontically treated tooth is critical for a successful restoration. Modification of the post length to accommodate a specific clinical situation is common. This study compared the retention of No. 1 and No. 2 Flexi-Post restorations shortened apically from 1 to 5 mm with that reported for full-length control No. 1 and No. 2 Flexi-Post dowels. The experimental material was divided into 10 groups with 10 samples in each group. Retentive values were recorded in pounds with a universal testing machine. Analysis of variance with a Tukey-Student range, multiple-comparison test showed no statistical differences from apical reductions of 1, 2, 3, and 5 mm including the full-length control Flexi-Post No. 1 system. With 4 mm of apical shortening statistically greater retention was recorded. No statistical differences resulted with apical reductions of 1 to 4 mm or with the full-length control Flexi-Post No. 2 system, but 5 mm of apical shortening caused significantly less retention.  相似文献   
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Designing behavior change programs and evaluating their effects on patient care has been a persistent challenge in research on continuing medical education. The challenge becomes even more complex when we aim to change behaviors that are interactive and highly influenced by the formal and informal institutional context. The authors describe an interdisciplinary continuing education program in bioethics that is designed to effect just such behaviors. The program aims to help hospital and long-term care facilities improve their ability to resolve the ethical dilemmas inherent in terminal care decisions. Targeted to interdisciplinary groups of physicians, nurses, social workers, pastoral counselors, and administrators, Decisions Near the End of Life will provide strategies and tools for examining institutional policies and team practices as well as more traditional information, education, and skill building. The authors describe the program's rationale and design, and raise questions about the potential for developing interdisciplinary, action-oriented CME on other topics.  相似文献   
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Lupus optic neuritis with negative serology   总被引:1,自引:0,他引:1  
A 56-year-old woman with a 12-year history of systemic lupus erythematosus presented with severe optic-disc swelling and blepharitis. At the same time, she developed acute pancreatitis and ultimately died of gram-negative sepsis. Although it appeared that the ocular and systemic disorders were manifestations of lupus, her serum antinuclear antibody and complement levels remained normal throughout her hospital course. Optic neuritis may be secondary to lupus, but the diagnosis is difficult to make when the serology is negative.  相似文献   
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We studied blood pressure and natriuretic responses to acute salt loading, and the effect of non-steroidal anti-inflammatory agents on these responses, in five healthy normotensive women aged 65 to 71 years. Five women aged 25 to 31 years acted as controls. Intravenous saline loading, with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h. Baseline blood pressures were higher in the elderly. Saline infusion without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in the older group only. Ibuprofen increased baseline SBP in the elderly (129 +/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen again raised blood pressure by about 25 mmHg in the elderly only. The elderly group showed markedly increased sodium excretion during saline loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP or sodium excretion in controls. Ageing appears to increase susceptibility to salt retention and hypertension from non-steroidal anti-inflammatory agents.   相似文献   
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