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991.
Limitations of plain radiographs may contribute to poor sensitivity in the detection of knee osteoarthritis and poor correlation with pain and physical function. Three-dimensional (3D) joint space width (JSW), measured from weight-bearing computed tomography (CT) images, may yield a more accurate correlation with patients’ symptoms. We assessed the cross-sectional association between 3D JSW and self-reported pain and physical function. Five hundred twenty eight knees (57% women) were analyzed from Multicenter Osteoarthritis Study participants. An upright weight-bearing CT scanner was used to acquire bilateral, weight-bearing, fixed-flexion images of the knees. A 3D dataset was reconstructed from cone beam projections and JSW was calculated across the joint surface. The percentages of the apposed medial tibiofemoral joint surface with JSW less than 2.0 and 2.5 mm, respectively, were calculated. Pain and physical function were measured using Western Ontario and McMaster Universities Osteoarthritis Index. Participants who reported greater pain severity tended to have a greater joint area with JSW less than 2.0 mm (P = .07 for the highest vs the lowest tertile). Participants who reported greater functional limitations had a greater joint area with JSW less than 2.0 mm (P = .02 for the highest vs the lowest tertile). There appears to be an association between the medial tibiofemoral area with JSW less than 2.0 mm and pain and physical function.  相似文献   
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Radiostereometric analysis (RSA) is the most accurate method of measuring component migration using radiographs but is restricted to use in prospective studies. Ein-Bild-Roentgen-analyze (EBRA)-Cup can be used retrospectively, but its accuracy to measure component migration following revision is unknown. This study aimed to determine the accuracy of EBRA-Cup measurements of uncemented acetabular component migration after revision total hip replacement (THR). The secondary aim was to compare the number of cases identified using EBRA-Cup and RSA as having proximally migrated above and below 1 mm at 2 years postoperatively. EBRA-Cup measurements were performed on plain antero-posterior pelvic radiographs taken at the same time as RSA radiographs in a prospective cohort of 53 hips undergoing acetabular revision. At 2 years, the mean difference between the RSA and EBRA-Cup measurements for 17 components used to treat pelvic discontinuity was 0.90 mm, significantly greater than the mean difference of 0.28 mm for 36 components without discontinuity (P = .0001). The mean difference between the RSA and EBRA-Cup measurements at 2 years for hips that were reconstructed with an acetabular component alone, 0.28 mm, was significantly lower than hips that were reconstructed with an acetabular component in combination with an augment and/or cage, 0.74 mm (P = .0005). In conclusion, EBRA-Cup can accurately measure migration of uncemented acetabular components used at revision THR. The presence of pelvic discontinuity, and addition of augments and cages, significantly influenced the accuracy of EBRA-Cup measurements. EBRA-Cup and RSA had good agreement on classification of components that migrated proximally above or below 1 mm at 2 years, with 100% sensitivity, and 87% specificity.  相似文献   
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OBJECTIVE: To determine the time to onset of analgesia of rofecoxib based on a patient-level meta-analysis of randomized, placebo-controlled, postoperative oral surgery pain studies. METHODS: A search on MEDLINE and of Merck data on file was conducted to identify studies that met the inclusion criteria. Meta-analysis inclusion criteria required that patients were treated with a single oral dose of rofecoxib 50 mg when they experienced moderate or severe pain after surgical extraction of > or = 2 third molars; study design involved patient randomization, double-blinding, and matching placebo, and onset data from individual patients were available. The meta-analysis of time to onset also required that studies used the two-stopwatch method. Eleven studies fulfilled the onset criteria and included patients who received a single dose of rofecoxib 50 mg (N = 1220) or placebo (N = 483). These studies were analyzed to determine time to onset of analgesia, time to perceptible pain relief, percentage of patients achieving onset of analgesia, and duration of analgesia. Six of the 11 studies included a nonselective nonsteroidal anti-inflammatory drug (N = 303) and were included in the onset meta-analysis for comparison. The meta-analysis of overall efficacy also required that data on total pain relief scores over 8 hours were available. Over-all effectiveness of analgesia was based on analysis of 13 studies involving 1330 rofecoxib patients and 570 placebo patients on the endpoints of total pain relief scores over 8 hours and patient global assessment of response to therapy at 24 hours. Eight of the 13 studies with a nonselective nonsteroidal anti-inflammatory drug comparator (N = 391) were included for the efficacy meta-analysis. RESULTS: Patient demographics and baseline characteristics were similar across treatment groups in each study. Median time to onset of analgesia for rofecoxib was 34 minutes (95% CI, 31-38 minutes), significantly faster than placebo, which did not achieve onset within the 4 hours the assessment was conducted (P < 0.001). Duration of analgesia for rofecoxib 50 mg was > 24 hours. Rofecoxib achieved a greater mean total pain relief score over 8 hours than placebo (17.4 versus 4.4; P < 0.001) and a greater patient response rate on patient global assessment of response to therapy at 24 hours than placebo (73% versus 16%; P < 0.001). Outcomes were similar between the rofecoxib group and the nonselective nonsteroidal anti-inflammatory drug group. CONCLUSION: In this meta-analysis of over 1200 rofecoxib-treated patients, a single dose of rofecoxib 50 mg demonstrated a rapid onset of analgesia in approximately half an hour combined with sustained effectiveness, supporting its use as a treatment of acute pain.  相似文献   
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Introduction: Phthalates, a class of commonly used compounds with widespread human exposure, have been described as obesogens, or chemicals that disrupt lipid metabolism and produce metabolic changes leading to increased risk of type 2 diabetes mellitus (DM) and cardiovascular disease (CVD). This communication provides a systematic review of the available epidemiologic evidence on associations between phthalate ester metabolites in urine or blood and various health endpoints related to overweight/obesity, DM or CVD. Methods: We followed the current methodological guidelines for systematic reviews to identify, retrieve and summarize the relevant epidemiological literature on the relation between phthalates and overweight/obesity, DM, CVD or related biomarkers. Each eligible paper was summarized with respect to methods and results with particular attention to study design and exposure assessment. As quantitative meta-analysis was not feasible, the study results were assessed qualitatively for inter- and intra-study consistency. Results: We identified 26 publications of epidemiologic studies that assessed associations between either urinary or serum phthalate metabolites and outcomes of interest. These studies represented 18 independent data sources. We found no inter- or intra-study consistency for any phthalate metabolite for any of the indicators of overweight/obesity, DM or CVD in children or adults. Most reported associations were not statistically significantly different from the null, some were positive, and others were inverse. All studies except two used cross-sectional analyses and for this reason could not be used to test causal hypotheses. Conclusion: The current epidemiological data do not support or refute the hypothesis that phthalates act as obesogens in humans.  相似文献   
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