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91.
Congenital coxa vara. A retrospective review   总被引:1,自引:0,他引:1  
Forty-two cases of coxa vara were retrospectively reviewed. All 42 cases were classified based on their history and roentgenographic appearance. Twenty-two cases of true congenital coxa vara were identified and are the primary focus of this review. In this study we have introduced the Hilgenreiner epiphyseal (HE) angle as measured on standard AP roentgenograms of the hip. Retrospectively, this angle was measured to aid in deciding candidacy for surgery, as well as a means of determining the amount of surgical correction necessary to prevent a recurrence of the deformity. The indication for surgery should be an HE angle of greater than 60 degrees. HE angles of less than 60 degrees and greater than 45 degrees represent a "gray zone" and should be observed. HE angles of less than 45 degrees will generally correct spontaneously without surgery.  相似文献   
92.
Maternal and Child Health Journal - The Maternal and Child Health (MCH) Pipeline Training Program, promotes development of a diverse health workforce by training undergraduate students from...  相似文献   
93.
Current strategies targeting serum cholesterol bring limited benefits to mortality and macrovascular events prevention among hemodialysis patients. Direct measurements and analysis on circulating markers of cholesterol homeostasis could be promising solutions to this bottleneck. We prospectively enrolled 90 maintenance hemodialysis patients and 9 healthy controls in 2019 for 1 year. We measured circulating desmosterol and lathosterol as markers for cholesterol synthesis and campesterol and sitosterol for cholesterol absorption. At baseline, hemodialysis patients showed higher levels of campesterol (p = 0.023) compared to healthy controls. During follow-up, we identified 14 (15.4%) patients who experienced macrovascular events. Comparisons of cholesterol homeostasis markers between cohorts with and without macrovascular events showed no significant differences in markers of cholesterol synthesis or absorption. Using logistic regression analysis, the odds ratio was not statistically significant for the prediction of macrovascular events after full-adjusting for age, sex, diabetes, serum albumin, cholesterol, and triglyceride. We concluded that hemodialysis patients demonstrated higher level of cholesterols absorption, indicated by circulating campesterol compared to healthy subjects. Markers for cholesterol homeostasis were not significantly associated with macrovascular events during a 1-year follow-up. Our results shed light on the novel therapeutic target of modulating cholesterol absorption in HD patients.  相似文献   
94.
BackgroundApproximately 15%-20% of total knee arthroplasty (TKA) patients do not experience clinically meaningful improvements. We sought to compare the accuracy and parsimony of several machine learning strategies for developing predictive models of failing to experience minimal clinically important differences in patient-reported outcome measures (PROMs) 1 year after TKA.MethodsPatients (N = 587) in 3 large Veteran Health Administration facilities completed PROMs before and 1 year after TKA (92% follow-up). Preoperative PROMs and electronic health record data were used to develop and validate models to predict failing to experience at least a minimal clinically important difference in Knee Injury and Osteoarthritis Outcome Score (KOOS) Total, KOOS JR, and KOOS subscales (Pain, Symptoms, Activities of Daily Living, Quality of Life, and recreation). Several machine learning strategies were used for model development. Ten-fold cross-validation and bootstrapping were used to produce measures of overall accuracy (C-statistic, Brier Score). The sensitivity and specificity of various predicted probability cut-points were examined.ResultsThe most accurate models produced were for the Activities of Daily Living, Pain, Symptoms, and Quality of Life subscales of the KOOS (C-statistics 0.76, 0.72, 0.72, and 0.71, respectively). Strategies varied substantially in terms of the numbers of inputs required to achieve similar accuracy, with none being superior for all outcomes.ConclusionModels produced in this project provide estimates of patient-specific improvements in major outcomes 1 year after TKA. Integrating these models into clinical decision support, informed consent and shared decision making could improve patient selection, education, and satisfaction.Level of EvidenceLevel III, diagnostic study.  相似文献   
95.
BackgroundFew studies evaluate racial disparities in costs and clinical outcomes for patients undergoing distal pancreatectomy (DP).MethodsWe queried the Healthcare Cost and Utilization Project State Inpatient Databases to identify patients undergoing DP. Multivariable regression (MVR) was used to evaluate the association between race and postoperative outcomes.Results2,493 patients underwent DP; 265 (10%) were black, and 221 (8%) were of Hispanic ethnicity. On MVR, black and Hispanic patients were less likely than whites to undergo surgery in high volume centers (OR 0.53, 95% CI [0.40, 0.71]; OR 0.45, 95% CI [0.32, 0.62]). Black patients had a greater risk of postoperative complication (OR 1.40, 95% CI [1.07, 1.83]), 90-day readmission (OR 1.53, 95% CI [1.15, 2.02]), prolonged length of stay (OR 1.74, 95% CI [1.25–2.44]), and of being a high cost outliers (OR 1.40, 95% CI [1.02, 1.91]) compared to white patients.ConclusionBlack patients have increased risk of having a postoperative complication, prolonged hospitalization, and of being a high-cost outlier than non-Hispanic whites.  相似文献   
96.
BackgroundTertiary hyperparathyroidism associated with end-stage renal disease is characterized by progression from secondary hyperparathyroidism to an autonomous overproduction of parathyroid hormone that leads to adverse health outcomes. Rates of parathyroidectomy (PTX) have decreased with the use of calcimimetics. Optimal timing of PTX in relation to kidney transplant remains controversial. We aimed to identify the most cost-effective strategy for patients with tertiary hyperparathyroidism undergoing kidney transplant.MethodsWe constructed a patient level state transition microsimulation to compare 3 management schemes: cinacalcet with kidney transplant, cinacalcet with PTX before kidney transplant, or cinacalcet with PTX after kidney transplant. Our base case was a 55-year-old on dialysis with tertiary hyperparathyroidism awaiting kidney transplant. Outcomes, including quality-adjusted life years, surgical complications, and mortality, were extracted from the literature, and costs were estimated using Medicare reimbursement data.ResultsOur base case analysis demonstrated that cinacalcet with PTX before kidney transplant was dominant, with a lesser cost of $399,287 and greater quality-adjusted life years of 10.3 vs $497,813 for cinacalcet with PTX after kidney transplant (quality-adjusted life years 9.4) and $643,929 for cinacalcet with kidney transplant (quality-adjusted life years 7.4).ConclusionCinacalcet alone with kidney transplant is the least cost-effective strategy. Patients with end-stage renal disease-related tertiary hyperparathyroidism should be referred for PTX, and it is most cost-effective if performed prior to kidney transplant.  相似文献   
97.
BackgroundApproximately 80% of general surgery residents undertake some form of fellowship training. Our objective was to characterize goals and burdens of the interview process among applicants to Comprehensive Endocrine Surgery Fellowship programs.MethodsParticipants included trainees from 2013 to 2019. Results for ranking questions are presented as a mean rank reported out of the total number of selections.ResultsResponse rate was 54% (n = 75). The most important goal for interviews was meeting the faculty (mean rank 2.4/9), followed by “behind the scenes information” and “make a good impression” (mean rank 3.6 and 3.7, respectively). The most substantial burden for the applicant was expense (mean rank 2.1/7), followed by time away from residency (mean rank 3.1/7). The economic burden of 51% of the applicants was $2,500 to $7,500. Geographic location and expense were the top 2 reasons applicants declined offers of interviews. Despite the process, 76% of respondents indicated that no improvements to the interview process are necessary. Alternative strategies such as videoconferencing or centralized interviews received little support (<10%).ConclusionDespite identifying several burdens, survey respondents believed that in-person interviews are an integral component of the fellowship application process. Indeed, 70% of applicants do not have a first-choice program before interviews, and meeting the faculty is ranked as the greatest priority goal. Our data illustrate the importance of individual specialties evaluating and optimizing their own processes for fellowship interviews.  相似文献   
98.
99.
海绵质骨螺旋钉拔出试验之生物力学分析   总被引:1,自引:1,他引:1  
评估螺旋钉设计优劣的简便方法之一为拔出试验。虽然比较用之海绵质骨试件可取自相同部位,自同一方向植入螺旋钉,并具有相同基准。然而因各处海绵质骨骼结构不尽相同,至今尚未有人探讨如使用不同之海绵质骨结构,例如近似等向性之杆状结构,或是板与杆组合之有强列方向排列者,对于螺旋钉拔出之最大力量有多大影响?采用牛股骨远端部位及牛颈椎C2~C6作为不同结构特性之试体。并各由两相互垂直之方向旋入螺旋钉,来做拔出试验。最后并建立一三维有限元素模型,用以研究螺纹周围之变形模式及其预测拔出最大力量的准确性。模型分析中以应变能密度准则作为破坏之参考标准。  相似文献   
100.
Autoradiography and anterograde horseradish peroxidase transport were used to examine retinocollicular projections in normal hamsters and in animals subjected to ablation of the ipsilateral, posterior neocortex at 1, 3, 6, 10 or 120 days of age. The crossed retinotectal projections of all groups were quite similar. There did, however, appear to be a slight increase in the density of the projection to the lower portion of the stratum griseum superficiale in the neonatally brain-damaged hamsters.The uncrossed pathway, on the other hand, was quite abnormal in the neonatally lesioned animals. In normals, the ipsilateral retinocollicular projection consisted almost entirely of a series of patches along the stratum yriseum superficiale-stratum opticum border in the rostral one-third of the colliculus. Only a few axons from the ipsilateral eye were observed in the caudal two-thirds of the tectum and these could only be visualized when horseradish peroxidase was used as the tracer. In all of the neonatally brain-damaged hamsters both autoradiography and horseradish peroxidase tracing demonstrated that the ipsilateral retina densely innervated the entire rostrocaudal extent of the colliculus.Retrograde tracing experiments demonstrated that the portion of the temporal retina which gave rise to the uncrossed retinocollicular projection in the normal hamsters was also the source of the expanded projection in the neonatally brain-damaged animals; and, further, that the numbers and areal distributions of ipsilaterally projecting retinal and retinocollicular ganglion cells were similar in the two groups.These findings suggest that, at least in the hamster, normal inputs from the two eyes may not be a sufficient condition for the development of the largely complementary pattern of collicular innervation by the two retinae.  相似文献   
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