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Serial measurements using dual-energy x-ray absorptiometry (DEXA) were undertaken to evaluate progressive periprosthetic bone loss in patients treated for primary bone tumors of the distal femur using an uncemented tumor prosthesis. Twelve patients underwent sequential DEXA analysis on average 26.5 and 90.9 months postsurgery. Changes in bone mineral density were measured in regions of interest (ROIs) around the prosthesis stem. The test-retest reliability coefficient (r) ranged from 0.92 to 0.99 for all ROI. In the most distal ROI (ROI1), 10 of 11 patients with 2 measurements showed no change or a small increase in absolute bone mineral density. The results in other ROIs were similar. This longitudinal DEXA data suggest that progressive bone resorption is not problematic with an uncemented distal femur endoprosthesis at intermediate follow-up. Key words: DEXA, stress shielding, uncemented endoprothesis, tumor, bone loss.  相似文献   
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OBJECTIVE: To determine the prevalence of hyperlipidemia among Saudis of both genders in rural and urban communities. METHODS: Selected Saudis in the age group of 30-70 years were studied over a 5-year period between 1995 and 2000 in Saudi Arabia. Data were obtained from history, physical examination, and analysis of fasting plasma lipids. The data were analyzed to classify individuals with hypercholesterolemia (HC) (total cholesterol > or =5.2 mmol/l), and hypertriglyceridemia (HT) (total triglycerides > or =1.69 mmol/l). Logistic regression analysis was performed to provide a risk assessment model and correlation with other coronary artery disease (CAD) risk factors. RESULTS: The number of study samples included in the final analysis was 16,819. The prevalence of HC was 54% with mean cholesterol level of 5.4+/-1.52 mmol/l. Prevalence of HC among males was 54.9% and 53.2% for females, while 53.4% among urban Saudis and 55.3% for rural Saudis. Hypertriglycemia prevalence was 40.3% with mean triglycerides level of 1.8+/-1.29 mmol/l. Males had statistically significant higher HT prevalence of 47.6% compared to 33.7% in females (p<0.0001). CONCLUSION: Hyperlipedimia is reaching higher prevalence rates in KSA. This finding may suggest that CAD will soon be a major health problem. Reduction in obesity by adopting healthier eating habits, and increasing physical activity are of considerable importance to our community.  相似文献   
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A retrospective review was made of 96 consecutive patients with large cell carcinoma of the lung admitted to Emory University Hospital over 10 years. Only 10 patients were seen with stage I lesions favorable for resection. The remainder were treated primarily with irradiation or chemotherapy. Mean survival for clinical stage I patients was 15.9 months; stage IIIA patients, 7.9 months; stage IIIB patients, 7.1 months; and stage IV patients, 5.8 months. Only 1 patient survived for 5 years. This distinct and highly aggressive form of lung cancer most commonly is seen at an advanced stage and is associated with an unusually dismal prognosis regardless of the method of treatment employed.  相似文献   
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BACKGROUND: The rapid evolution of implantable cardioverter-defibrillator (ICD) leads has resulted in thinner active fixation leads. While these advances have made the leads more versatile, new configurations may be associated with unforeseen complications. OBJECTIVE: The purpose of this study was to determine the incidence of perforation and dislodgement of defibrillator leads in a single center in the year 2005. METHODS: All patients who underwent percutaneous ICD implantation at the Massachusetts General Hospital using an endocardial right ventricular lead were included in this study. The specific leads analyzed were the Riata (1580/1581 and 1590/1591, St. Jude Medical, St Paul, Minnesota, USA;) and Sprint Fidelis (6949-65, Medtronic, Minneapolis, Minnesota, USA.). Information was collected retrospectively. RESULTS: A total of 130 Riata leads and 111 Sprint Fidelis leads were implanted at the Massachusetts General Hospital during this time period. A total of five lead perforations occurred in patients implanted with the Riata lead as compared with none with the Sprint Fidelis lead (3.8% vs. 0%, respectively; P <.05). Two of the five patients with perforation required pericardiocentesis for tamponade. Clinical symptoms of perforation developed 1-10 days after implant. Moreover, there were five additional lead revisions in the Riata group, which were likely due to dislodgement and/or microperforation, as compared with none in the Sprint Fidelis group (7.7% vs. 0%, respectively; P <.005). CONCLUSIONS: In 2005, at one institution, there were significantly more cardiac perforations and lead revisions with the Riata lead as compared with the Sprint Fidelis right ventricular defibrillator lead. Further data are required to determine whether certain lead characteristics are responsible for this observation.  相似文献   
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INTRODUCTION Hepatitis A virus (HAV) infection is common. In general, hepatitis A is a self-limited illness with a recovery time measured in months[1]. Young children are often asymptomatic, whereas adults are more likely to be symptomatic and may present…  相似文献   
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A 2½-year-old girl developed a bilateral occipital infarct following severe gastroenteritis with bilateral vision of light perception. Evaluations for sickle cell anemia, hemolytic anemia and coagulopathies were negative. Cortical blindness is an uncommon but dramatic complication of gastroenteritis, hence the need of prompt hydration and other supportive measures to avoid irreversible visual loss or mental sequela.Key Words: Occipital infarct, Gastroenteritis, Visual recovery  相似文献   
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