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81.
The outcome of uncemented hip arthroplasty in patients with Paget's disease is unknown. The clinical and radiographic records of patients with Paget's disease affecting the hip who had total hip arthroplasty using uncemented components against pagetic bone were reviewed. There were 18 patients (19 hips) with an average age of 71.3 years (range, 54-85 years). Followup averaged 7 years (range, 2-15 years). Surgery often was reported to be demanding technically because of hard sclerotic bone and excessive bleeding in some patients. Estimated blood loss averaged 996 mL (range, 200-2500 mL). Harris hip scores improved significantly. There was clinical and radiographic evidence of bone ingrowth in all patients. Six of 19 hips had heterotopic bone. One hip had severe Brooker Grade IV heterotopic ossification and the patient required excision of the ossification at 5 years. One hip was unstable (subluxating) at the latest followup. There was no revision for component loosening and no recognized cases of clinical or radiographic loosening of any uncemented implants. Results of total hip arthroplasty using uncemented components in patients with Paget's disease are excellent overall, with an extremely low risk of component loosening during the first decade after implantation. These patients may be at higher risk for heterotopic bone formation and increased perioperative blood loss because of hypervascularity of the bone.  相似文献   
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83.
BackgroundOsteoarthritis (OA) and osteoporosis (OP) are the 2 most common bone disorders associated with aging. We can simply assume that older patients have a higher incidence of OA and OP with more severity. Although several papers have conducted studies on the relationship between OA and OP, none of them has demonstrated a conclusive link. In this study, we used radiological knee OA and bone mineral density (BMD; T-score of the total hip and lumbar spine) to analyze the incidence of OA and OP in a large population. We aimed to determine the relationship between OA and OP and investigate the associated risk factorsMethodsThis cross-sectional study used data extracted from the 2010–2012 Korea National Health and Nutrition Examination Survey. We evaluated a total of 4,250 participants aged ≥ 50 years who underwent knee radiography and dual-energy X-ray absorptiometry and their laboratory results. The relationship between radiological knee OA and BMD was assessed. The generalized linear model was used to evaluate the relationship between BMD and Kellgren-Lawrence (KL) grade.ResultsThe higher KL grade was associated with older age, higher body mass index (BMI), female sex, and lower hemoglobin level (p < 0.001). No significant association was found between OA and the following variables: white blood cell, platelet, total cholesterol, vitamin D, alkaline phosphatase, parathyroid hormone, hypertension, diabetes, asthma, dyslipidemia, smoking status, alcohol consumption, and regular exercise (p > 0.05). After adjusting for confounding factors (age, BMI, diabetes, hypertension, smoking, and alcohol consumption), the average T-scores of total hip and lumbar spine were the highest in the mild OA group with KL grade 2 (−0.22 ± 1.08 and −0.89 ± 1.46, respectively, p < 0.001). The average T-scores of the total hip and lumbar spine significantly decreased as OA progressed from moderate (KL grade 3; −0.49 ± 1.05 and −1.33 ± 1.38, respectively, p < 0.001) to severe (KL grade 4; −0.73 ± 1.13 and −1.74 ± 1.75, respectively, p < 0.001). T-scores of the moderate-to-severe OA group were significantly lower than those of the non-OA group (KL grades 0 and 1, p < 0.001).ConclusionsCompared with the non-OA group, BMD (T-scores of the total hip and lumbar spine) was higher in the mild OA group and lower in the moderate-to-severe OA group.  相似文献   
84.
Radiotherapy and limb-preserving surgery has replaced amputation and compartmental resection for treatment of soft tissue sarcomas. However, the role of radiotherapy in low-grade tumors remains unclear. This study reviews the outcomes of 132 patients who received multimodality treatment for low-grade soft tissue sarcoma. Large primary tumors (> 5 cm) and the absence of radiotherapy correlated with local recurrence. Radiotherapy was most effective in patients operated on with marginal margins. Patients who were treated with wide surgical margins or had small tumors (< or =5 cm) showed no benefit with adjuvant radiotherapy. Size greater than 5 cm and local recurrence correlated with metastasis. Radiotherapy appears to be important in the management of low-grade soft tissue sarcoma. The principles of local treatment for low-grade soft tissue sarcoma should be the same as for high-grade tumors with a combination of surgery and adjuvant radiotherapy. In a subset of patients with small and widely excised tumors, consideration may be given to withholding radiotherapy. Local recurrence and metastasis from low-grade soft tissue sarcoma may occur as long as 1 decade after primary tumor resection. Long-term review of patients with low-grade tumors may be indicated.  相似文献   
85.
INTRODUCTION/OBJECTIVE: N-acetyltransferase 2 (NAT2), mapped to 8p22, is a polymorphic enzyme which metabolizes aromatic amines. Loss of heterozygosity of 8p22 is associated with an increased risk of bladder cancer. This study evaluated NAT2 and chromosome 8 in sequential tumours from bladder cancer patients to determine if NAT2 alterations increase the risk of progression. MATERIALS AND METHODS: Thirty-seven sequential carcinomas from 19 patients were assessed using fluorescence in situ hybridization. RESULTS: Five carcinomas showed loss of NAT2; 4 of these were from pTa/pT1 tumours. Polysomy 8 was observed in 4 of 14 (29%) primary carcinomas (pTa/pT1), in 4 of 12 (33%) pTa/pT1 recurrences, and in 90% (9/10) of the detrusor muscle invasive tumours (pT2+). 6 of 8 (75%) locally invasive tumours with polysomy 8 were from patients who subsequently developed disease progression (pT2+). In total, 13.5% (5/37) of the carcinomas were abnormal for NAT2, and 46% (17/37) were abnormal for chromosome 8 copy number. Polysomy 8 was associated with high grade (p = 0.01) and stage (p = 0.03) and disease progression (p = 0.03). CONCLUSION: Whilst there does not appear to be an association between loss of NAT2 and risk of progression in transitional cell carcinoma, the high rate of polysomy of chromosome 8 implies that other genes on this chromosome significantly influence disease progression.  相似文献   
86.
Thromboprophylaxis with 60 mg enoxaparin is safe in hip trauma surgery   总被引:1,自引:0,他引:1  
BACKGROUND: Little information is available concerning dosage and optimal initiation of thromboprophylactic therapy with low-molecular-weight heparin (enoxaparin) in nonelective hip surgery. The aim of our prospective study was to evaluate the incidence of clinically apparent deep vein thrombosis (DVT), pulmonary embolism (PE), and major hemorrhage in patients receiving thromboprophylaxis with enoxaparin undergoing hip surgery after hip fracture. METHOD: From 946 consecutive patients admitted with hip fractures, 897 were operated on and received enoxaparin according to the following regimen: Preoperative heparinization from time of admission onwards. Administration of 60 mg enoxaparin, in two doses (20 and 40 mg subcutaneously), during the first 5 days postoperatively. Prophylaxis for a minimum of 5 weeks (40 mg daily). RESULTS: Clinical signs of DVT were present in 37 patients (4.2%), who all underwent venography. In five patients, DVT was confirmed (0.6%). None of these patients suffered from PE. Another four patients (0.4%) developed clinical signs of PE, and suspected diagnosis was confirmed by computed tomographic scan in two (0.2%). No deaths because of PE were observed. Major hemorrhage occurred in 42 patients (4.7%), there was one death from hemorrhage caused by an intracerebral event. No case of heparin-induced thrombocytopenia type II was observed. CONCLUSION: Thromboprophylaxis with 60 mg enoxaparin daily, in split doses, starting before surgery, is safe and appropriate in patients with hip fractures. Clinically apparent DVT and PE are rarely observed, and bleeding complications are comparable to those occurring with a conventional thromboprophylactic regimen.  相似文献   
87.
Aseptic loosening is a common cause of failure in large tumor endoprostheses. The concept of extracortical bone-bridging was developed to tackle the problem of loosening. New bone which forms across the junction of the bone-prosthesis junction is believed to improve fixation by controlling the transfer of stresses across the junction as well as by giving additional stability to the prosthesis. We present the long-term experience with this concept following major reconstruction after tumor and non-tumor conditions in 31 patients. The overall function was good for upper and lower limb prostheses. Most patients had extracortical bone bridging which was maintained for over 10 years. In 1/3 of patients this involved over 75% of the prosthetic circumference. Prosthetic survival was best with intercalary devices, followed by proximal femoral and distal femoral prostheses. Survival of prostheses in young active patients was similar to that reported in older patients undergoing primary joint replacement.  相似文献   
88.
Influence of aging on hepatic and peripheral glucose metabolism in humans   总被引:1,自引:0,他引:1  
Mechanisms of glucose intolerance with aging were studied by comparing the metabolic response to glucose ingestion in 10 young (20-23 yr) and 10 elderly (73-80 yr) normal men with the simultaneous application of the forearm and double-isotope techniques. The latter technique consisted of a primed-constant infusion of [3-3H]glucose followed by the administration of an oral glucose load (mean +/- SE, 90.7 +/- 0.7 g) containing [1-14C]glucose. Fasting plasma glucose and insulin concentrations were similar in young and elderly subjects, but in the elderly, glucose tolerance was markedly impaired. Although in the elderly the initial rise in insulin levels (delta, i.e., the incremental area under the curve) from 0 to 30 min was delayed (P less than .02), the response from 0 to 45 min, 0 to 60 min, and thereafter equaled that in the young group, and from 90 to 240 min insulin concentrations in the elderly exceeded those in young subjects. Basal hepatic glucose output (HGO) was similar in young and elderly men (2.13 +/- 0.10 and 1.97 +/- 0.14 mg.kg-1.min-1, respectively). Similar proportional reductions in HGO from 0 to 270 min after glucose loading occurred in young (59.7 +/- 10.3%) and elderly (50.3 +/- 4.9%) subjects but was delayed in the elderly. Suppression of HGO was observed in the young 30 min after glucose ingestion (P less than .02), but not before 60 min in the elderly subjects (P less than .05). The systemic appearance of ingested glucose (0-270 min) was slowed with age (80.7 +/- 3.1 and 66.9 +/- 4.3% of the oral load in the young and elderly groups, respectively; P less than .02). Initial increments in both total glucose disappearance (Rd) and forearm glucose uptake (FGU) from 0 to 60 min after glucose loading were decreased in the elderly (Rd, 4.1 +/- 0.7 vs. 11.5 +/- 1.3 g, P less than .001; FGU, 17.2 +/- 1.4 vs. 24.6 +/- 2.5 md/dl forearm, P less than .02). The overall increment (delta, 0-270 min) in Rd was reduced with age (47.2 +/- 2.9 and 34.5 +/- 3.6 g, P less than .02 in the young and elderly, respectively), but the corresponding data for FGU were similar in the two groups.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
89.
Problems and pitfalls in the management of Hirschsprung's disease   总被引:3,自引:0,他引:3  
A study of 126 patients with histologically proven Hirschsprung's disease revealed various problems associated with the surgical management of these cases. Complications such as prolapse, stricture, and cuff abscess were noted in patients undergoing endorectal pull-through (ERPT). These complications were not always obvious, and in some cases, the diagnosis became apparent only several years after definitive surgery. Specific technical aspects of the procedure probably play an important role in the pathogenesis of these problems. Ultrashort-segment Hirschsprung's disease remains a problem in treatment. Rectal myectomy gives good results in some cases and unsatisfactory results in others.  相似文献   
90.
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