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991.
992.
Shreyasee Amin David L Kopperdhal L Joseph Melton III Sara J Achenbach Terry M Therneau B Lawrence Riggs Tony M Keaveny Sundeep Khosla 《Journal of bone and mineral research》2011,26(7):1593-1600
Finite‐element analysis (FEA) of quantitative computed tomography (QCT) scans can estimate site‐specific whole‐bone strength. However, it is uncertain whether the site‐specific detail included in FEA‐estimated proximal femur (hip) strength can determine fracture risk at sites with different biomechanical characteristics. To address this question, we used FEA of proximal femur QCT scans to estimate hip strength and load‐to‐strength ratio during a simulated sideways fall and measured total hip areal and volumetric bone mineral density (aBMD and vBMD) from QCT images in an age‐stratified random sample of community‐dwelling adults age 35 years or older. Among 314 women (mean age ± SD: 61 ± 15 years; 235 postmenopausal) and 266 men (62 ± 16 years), 139 women and 104 men had any prevalent fracture, whereas 55 Women and 28 men had a prevalent osteoporotic fracture that had occurred at age 35 years or older. Odds ratios by age‐adjusted logistic regression analysis for prevalent overall and osteoporotic fractures each were similar for FEA hip strength and load‐to‐strength ratio, as well as for total hip aBMD and vBMD. C‐statistics (estimated areas under ROC curves) also were similar [eg, 0.84 to 0.85 (women) and 0.75 to 0.78 (men) for osteoporotic fractures]. In women and men, the association with prevalent osteoporotic fractures increased below an estimated hip strength of approximately 3000 N. Despite its site‐specific nature, FEA‐estimated hip strength worked equally well at predicting prevalent overall and osteoporotic fractures. Furthermore, an estimated hip strength below 3000 N may represent a critical level of systemic skeletal fragility in both sexes that warrants further investigation. © 2011 American Society for Bone and Mineral Research. 相似文献
993.
Marantes I Achenbach SJ Atkinson EJ Khosla S Melton LJ Amin S 《Journal of bone and mineral research》2011,26(12):2860-2871
There remains little consensus on the link between vitamin levels and muscle mass or strength. We therefore investigated the association of serum 25-hydroxyvitamin D (25(OH)D), 1,25-dihydroxyvitamin D (1,25(OH)(2) D), and parathyroid hormone (PTH) levels with skeletal muscle mass and strength. We studied 311 men (mean age, 56 years; range, 23-91 years) and 356 women (mean age, 57 years; range, 21-97 years) representing an age-stratified, random sample of community adults. Multivariate linear regression models were used to examine the association of skeletal muscle mass (by total body dual-energy X-ray absorptiometry) and strength (handgrip force and isometric knee extension moment) with each of 25(OH)D, 1,25(OH)(2) D, and PTH quartiles, adjusted for age, physical activity, fat mass, and season. We found no consistent association between 25(OH)D or PTH and any of our measurements of muscle mass or strength, in either men or women. However, in subjects younger than 65 years, there was a statistically significant association between low 1,25(OH)(2) D levels and low skeletal mass in both men and women and low isometric knee extension moment in women, after adjustment for potential confounders. Modestly low 25(OH)D or high PTH levels may not contribute significantly to sarcopenia or muscle weakness in community adults. The link between low 25(OH)D and increased fall risk reported by others may be due to factors that affect neuromuscular function rather than muscle strength. The association between low 1,25(OH)(2) D and low skeletal mass and low knee extension moment, particularly in younger people, needs further exploration. 相似文献
994.
Dimitrios?Lytras Steven?W.?M.?Olde Damink Zahir?Amin Charles?J.?Imber Massimo?MalagóEmail author 《Journal of gastrointestinal surgery》2011,15(3):489-495
Background
The application of endobiliary self-expandable metallic stents (SEMS) is considered the palliative treatment of choice in patients with biliary obstruction in the setting of inoperable malignancies. In the presence of SEMS, however, radical surgery is the only curative option when the resectability status is revised in case of malignancies or for overcoming complications arising from their application in benign conditions that masquerade as inoperable tumours. The aim of our study was to report our surgical experience with patients who underwent an operation due to revision of the initial palliative approach, whilst they had already been treated with biliary SEMS exceeding the hilar bifurcation. 相似文献995.
996.
This paper aims to describe the pathophysiology and management of the main endocrine complications of pregnancy. For each endocrine dysfunction, the issues with the fetus, the mother, obstetric complications, and the long term prognosis for the disease itself need to be considered. Key management issues are highlighted with each condition. Thyroid dysfunction and goitre are common while management is relatively straightforward. Adrenal, pituitary, and parathyroid diseases present less commonly in pregnancy. Early recognition of endocrine disease in pregnancy and appropriate management has the potential to improve outcome for the mother and fetus in the short and long term. 相似文献
997.
D.J. Anh MD Henry A. Chen MD Christian S. Eversull MD Nicholas J. Mourlas PhD R. Hardwin Mead MD L. Bing Liem DO Henry H. Hsia MD Paul J. Wang MD Amin Al-Ahmad MD 《Heart rhythm》2006,3(8):875-878
BACKGROUND: Despite improvements in cardiac resynchronization therapy (CRT) implantation techniques, a significant minority of CRT attempts are unsuccessful. Inability to cannulate the coronary sinus (CS) because of difficult anatomy is a major reason for unsuccessful CRT implantation. Direct visualization of intracardiac structures during the implant may facilitate access into the CS. The present study describes CRT implantation with the aid of an endocardial visualization catheter (EVC). METHODS: Fifty-eight consecutive patients (mean age 72 +/- 12 years; ejection fraction 26.2% +/- 7.0%; New York Heart Association [NYHA] class 2.9) underwent CRT implantation using a steerable fiberoptic EVC (Acumen Medical, Inc., Sunnyvale, CA). RESULTS: The EVC was able to visualize the CS ostium in all cases. The CS was successfully cannulated in 57 (98.3%) of 58 patients. The time from vascular access to CS visualization was 6 +/- 5 minutes, and the total time to CS access was 8 +/- 6 minutes. Successful left ventricle (LV) lead implantation was accomplished in 55 (94.8%) of 58 patients. Three patients who had a previous history of failed LV lead implantation were successfully implanted using the EVC. CONCLUSION: Fiberoptic imaging of intracardiac structures during CRT implantation may be performed rapidly in a wide range of patients with an EVC. The ability to visualize right atrial anatomy may aid CS access and LV lead implantation. 相似文献
998.
Nabavizadeh SH Safari M Amin R 《Iranian journal of allergy, asthma, and immunology》2006,5(4):199-200
Kawasaki disease is a multi system disorder with varying clinical expressions. This disease is an acute systemic vasculitis of unknown etiology that has recently recognized as a leading cause of acquired heart disease in children of many developed countries. We describe an unusual instance of hair loss in a patient with Kawasaki disease. A 26 months old boy developed prolonged high fever, bilateral conjunctival infection, arthralgia and erythromatosis skin rash. He was admitted to the hospital with the diagnosis of Kawasaki disease. Laboratory results included an erythrocyte sedimentation rate (ESR) above 100 and platelet count > 1000,000. The patient developed acute and unprovoked scalp hair loss. He was treated with intravenous immunoglobulin (IVIG) 2 g/kg and aspirin 100 mg/kg/day with complete improvement of signs and symptoms. This report documents hair loss as an uncommon presentation of Kawasaki disease. 相似文献
999.
Polyclonal anti-thymocyte globulin (ATG) is used as an immunosuppressive agent in the treatment of aplastic anemia (AA). Serum sickness is a recognized side effect of ATG. We observed abnormal skin manifestation in patient with aplastic anemia who had been treated with ATG. We conclude that abnormal immune function caused by aplastic anemia and ATG and corticosteroids may aggravate the signs of serum sickness. 相似文献