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71.
Mark F. Zhu Katy Kim Alana Cavadino Brendan Coleman Jacob T. Munro Simon W. Young 《The Journal of arthroplasty》2021,36(1):305-310.e1
BackgroundProsthetic joint infection (PJI) is the most common cause of failure following total knee arthroplasty (TKA). This study aimed to determine the success of debridement, antibiotics, and implant retention (DAIR) in a large cohort of TKA PJIs and assess the utility of current classification systems in predicting DAIR outcomes in early postoperative, late hematogenous, and chronic PJIs.MethodsIn a multicenter review over 15 years, 230 patients underwent DAIR for first episode PJI following primary TKA. Patient demographics, disease and surgical factors, treatment regime, and outcomes were identified. Univariate and multivariate survival analyses were performed to identify factors associated with successful DAIR. Continuous variables with predictive value were further analyzed using receiver operating characteristic curves. The ability to predict DAIR outcomes of multiple classification systems was also assessed.ResultsPatients were followed for an average of 6.9 years. The overall success rate of DAIR was 53.9%. On receiver operating characteristic analysis, 3 months (area under the curve = 0.63) and 1-year age (area under the curve = 0.66) of implant cut-offs was similarly predictive of outcomes. On multivariate survival analysis, DAIR was successful in 64% of “early” PJIs (implant <1 year) vs 38% of “late hematogenous” PJIs (implant >1 year; odds ratio [OR] 1.78, P = .01). For late PJIs (implant >1 year), Staphylococcus aureus (OR 4.70, P < .001) and gram-negative infections (OR 2.56, P = .031) were risk factors for DAIR failure.ConclusionDAIR has a high failure rate in all PJIs occurring more than a year post primary TKA, particularly when caused by S aureus or gram-negative bacteria. The age of implant is an important predictor of DAIR outcomes. 相似文献
72.
Recovery of motor function after spinal-cord injury--a randomized, placebo-controlled trial with GM-1 ganglioside 总被引:19,自引:0,他引:19
BACKGROUND. Spinal-cord injury is devastating; until recently, there was no medical treatment to improve recovery of the initial neurologic deficit. Studies in animals have shown that monosialotetrahexosylganglioside (GM-1) ganglioside enhances the functional recovery of damaged neurons. METHODS. A prospective, randomized, placebo-controlled, double-blind trial of GM-1 ganglioside was conducted in patients with spinal-cord injuries. Of 37 patients entered into the study, 34 (23 with cervical injuries and 11 with thoracic injuries) completed the test-drug protocol (100 mg of GM-1 sodium salt or placebo intravenously per day for 18 to 32 doses, with the first dose taken within 72 hours of the injury) and a one-year follow-up period. Neurologic recovery was assessed with the Frankel scale (comprising five categories) and the American Spinal Injury Association (ASIA) motor score (a scale of scores from 0 to 100, derived from strength tests of 20 specific muscles, each scored from 0 to 5). RESULTS. There was a significant difference between groups in the distribution of improvement of Frankel grades from base line to the one-year follow-up (improvement of 0, 1, 2, and 3 grades in 13, 4, 1, and 0 patients, respectively, in the placebo group and 8, 1, 6, and 1 patients, respectively, in the GM-1 group; P = 0.034 by the Cochran-Mantel-Haenszel chi-square test). The GM-1-treated patients also had a significantly greater mean improvement in ASIA motor score from base line to the one-year follow-up than the placebo-treated patients (36.9 vs. 21.6 points; P = 0.047 by analysis of covariance with the base-line ASIA motor score as the covariate). An analysis of individual muscle recoveries revealed that the increased recovery in the GM-1 group was attributable to initially paralyzed muscles that regained useful motor strength rather than to strengthening of paretic muscles. CONCLUSIONS. This small study provides evidence that GM-1 enhances the recovery of neurologic function after one year. A larger study must be conducted, however, before GM-1 is considered efficacious and safe in treating spinal-cord injury. 相似文献
73.
Nasogastric and intravenous infusions of (+)-4-propyl-9-hydroxynaphthoxazine (PHNO) in Parkinson's disease. 下载免费PDF全文
R J Coleman N P Quinn M Traub C D Marsden 《Journal of neurology, neurosurgery, and psychiatry》1990,53(2):102-105
(+)-4-propyl-9-hydroxynaphthoxazine (PHNO) is a new dopamine agonist which is capable of producing a sustained response in parkinsonian patients with "on-off" fluctuations when given as a continuous infusion either nasogastrically or intravenously. These data suggest that a sustained release formulation of PHNO may provide a significant, new treatment for patients with "on-off" fluctuations. 相似文献
74.
Improved methodology for analyzing local and distant recurrence 总被引:4,自引:0,他引:4
R Gelman R Gelber I C Henderson C N Coleman J R Harris 《Journal of clinical oncology》1990,8(3):548-555
Studies of radiation therapy and/or surgery in the treatment of cancer frequently use actuarial methods to estimate curves of time to local failure and compare two such curves with statistical methods originally developed for survival data. In such analyses, patients who fail first in distant sites or die before local failure are considered censored for time to local failure. While the arithmetic of these calculations is usually correct, the interpretation of the results is almost universally incorrect. For example, an actuarial Kaplan-Meier curve of time to breast recurrence after breast conserving treatment consistently overestimates the percentage of patients who would benefit from a subsequent mastectomy. Actuarial methods require the assumption that time to local failure and time to distant failure are statistically independent. For most human malignancies this is not a reasonable assumption, since there are always some patient subgroups at high risk of both local and distant failure and some patient subgroups at low risk for either type of failure. Without the assumption of independence, the time to local failure distribution is not well defined. The basic problem is that estimating time to local failure falls into the category of analyzing "competing risks," since the various causes of failure are competing for the same patient. For this reason, the effects of a particular treatment on local failure cannot be assessed separately from its effects on distant failure. This report explains the concepts of statistical independence, nonidentifiability, and competing risks and illustrates the pitfalls of using actuarial methods to assess local tumor control.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
75.
Benzocaine-mediated methaemoglobin-generation was compared with that of dapsone in vitro. Direct incubation of benzocaine with washed human erythrocytes alone at up to 15 mM did not result in significant methaemoglobin formation (0.4 ± 0.1%). With rat microsomes, dapsone-dependent methaemoglobin formation was almost two-fold that of benzocaine at 30 min (56.5 ± 0.7% vs 31.6 ± 2.4% P < 0.005)). Benzocaine-mediated methaemoglobin formation was significantly reduced in the presence of DDC (diethyldithiocarbamate) at the 10 (P < 0.005) and 20 (P < 0.025) min time points. At 30 min, cimetidine reduced benzocaine-mediated methaemoglobin from 34.4 ± 8.7% to less than 3% (P < 0.005). The methaemoglobin forming capacity of dapsone was significantly inhibited at all three time points by both DDC (P < 0.005) and cimetidine (P < 0.005). Incubation of benzocaine with microsomes from five human livers showed that each liver produced methaemoglobin-forming metabolites. No inhibitory effect was seen with DDC, although cimetidine caused a significant reduction (32.8 ± 12.4% overall) in benzocaine-mediated methaemoglobin formation in the four livers tested. 相似文献
76.
77.
78.
Gray marketing 总被引:2,自引:0,他引:2
79.
Provenzale JM Arata MA Turkington TG McLendon RE Coleman RE 《AJR. American journal of roentgenology》1999,172(4):1103-1107
OBJECTIVE: The purpose of this study was to correlate 18F-fluorodeoxyglucose positron emission tomography (PET) and MR imaging features of cerebral gangliogliomas before and after PET-MR image registration. CONCLUSION: After registration of PET and MR images, all six gangliogliomas in our series were shown to have heterogeneous metabolic activity. Areas of hypermetabolic activity were seen in all lesions. In five of the six cases, PET-MR image registration provided information regarding tumor metabolism that was not available on nonregistered hard-copy examinations. 相似文献
80.
Margaret M. Coleman Arun Bardwaj Vincent V. W. S. Chan 《Journal canadien d'anesthésie》1999,46(5):464-466