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Clinical outcomes data can be used to facilitate patient management decisions, assess clinician and organizational performance, and to provide evidence for the effectiveness of surgery and rehabilitation. The validity of the inferences made from outcomes data are dependent on the validity of the outcomes measures themselves and the circumstances under which the data were collected, analyzed, and interpreted. Clinical outcomes may include measures of impairment of body structure and function, activity limitation, and participation restriction. However, because the relationship between impairment and the resulting activity limitation and participation restriction is not direct, and because activity limitations and participation restrictions are of the utmost concern to the athlete, the primary clinical outcome should be measures of activity limitation and participation restriction. Activity limitation and participation restriction may be measured either through direct observation of performance or by general or specific measures of health related quality of life. Clinical outcomes data must be collected systematically to ensure valid inferences from the data.  相似文献   
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Dissection of the thoracic aorta is a life-threatening event requiring imaging studies to define the level of the tear and the intinmal flap. The “gold standard” has been angiography. This method may fail to demonstrate the dissection, however, due to overlap of the true and false lumens or a very thin flap that is imaged en face rather than tangentially. Computed tomography has a diagnostic accuracy of 95%, but can fail to image the dissection due to technical factors or a thrombosed false hunen. Magnetic resonance imaging requires a hemodynamically stable and cooperative patient. A diagnostic algorithm is proposed for diagnosis of aortic dissection based on renal function and the surgeon's imaging modality preference.  相似文献   
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The performances of three widely different cathode materials (Pt, strontium-doped lanthanum manganite (LSM), and NiO) have been compared for use with proton conducting Li2SO4–Al2O3 composite electrolyte, using H2S–air and H2–air fuel cells operating at 600 °C. Surface analysis and electrochemical techniques were used to characterize fresh and used electrode materials. Pt or LSM cathodes each became covered with Li2SO4 and Al2O3 and, as a consequence, the fuel cells showed poor performance. In contrast, the NiO cathode catalyst did not become covered with Li2SO4 and good fuel cell performance was achieved. Exceptionally good current densities of over 100 mA/cm2 and power densities of over 30 mW/cm2 were obtained for H2S–air fuel cells having Mo–Ni–S anode catalysts. Slight agglomeration of NiO particles during fuel cell operation had only a minor effect on performance.  相似文献   
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There is limited information regarding oral health status and other predictors of oral health‐related quality of life. An association between oral health status and perceived oral health‐related quality of life (OHQOL) might help clinicians motivate patients to prevent oral diseases and improve the outcome of some dental public health programs. This study evaluated the relationship between older persons' OHQOL and their functional dentition, caries, periodontal status, chronic diseases, and some demographic characteristics. A group of 733 low‐income elders (mean age 72.7 ISD=4.71, 55.6% women, 55.1% members of ethnic minority groups in the U.S. and Canada) enrolled in the TEETH clinical trial were interviewed and examined as part of their fifth annual visit for the trial. OHQOL was measured by the Geriatric Oral Health Assessment Index (GOHAI); oral health and occlusal status by clinical exams and the Eichner Index; and demographics via interviews. Elders who completed the four‐year assessment had an average of 21.5 teeth (SD=6.9). with 8.5 occluding pairs (SD=4.6), and 32% with occlusal contacts in all four occluding zones. Stepwise multiple regressions were conducted to predict total GOHAI and its subscores (Physical, Social, and Worry). Functional dentition was a less significant predictor than ethnicity and being foreign‐bom. These variables, together with gender, years since immigrating, number of carious roots, and periodontal status, could predict 32% of the variance in total GOHAI, 24% in Physical, 27% in Social, and 21 % in the Worry subscales. These findings suggest that functional dentition and caries influence older adults' OHQOL, but that ethnicity and immigrant status play a larger role.  相似文献   
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