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BACKGROUND: Autoimmune hepatitis (AIH) is an inflammatory disease of unknown origin that is responsible for progressive liver necrosis and ultimately cirrhosis. OBJECTIVE: Our aim was to evaluate the characteristics of autoimmune hepatitis presenting in the pediatric age. MATERIAL AND METHODS: We conducted a retrospective study of all patients diagnosed with AIH in our hospital department during the last 10 years. Variables analyzed included age, sex, clinical presentation, hepatic function, immunoglobulins, autoimmunity markers, histology, treatment, need for transplant, and clinical evolution. According to the positive level of auto-antibodies, AIH patients were classified as type I AIH (ANA and/or smooth-muscle antibodies) and type II (anti-LKM-1). RESULTS: Seven patients were diagnosed in this period -5 girls (71.5%) and 2 boys (28.5%). Five patients presented with type-I serological markers, and two with type-II markers. Age range at diagnosis was from 21 months to 12 years. In the type-I group, 3 patients presented with acute hepatitis while 2 other patients were diagnosed from laboratory findings while asymptomatic. Elevated aminotransferase (10 times the normal level) was observed in 71.5%, and 85% had elevated immunoglobulins. Treatment with azathioprine and prednisone was started after diagnosis with an average time to remission of 14 months. Two patients relapsed following steroid withdrawal. CONCLUSION: AIH can have different forms of clinical presentation, and is sometimes indistinguishable from viral hepatitis. AIH must be ruled out in patients presenting with concomitant elevation of aminotransferases and immunoglobulins. The commonly accepted treatment is a combination of azathioprine and corticosteroids. A high percentage of patients experience a relapse of disease after steroids are withdrawn. Therefore, some patients will need to stay on combined therapy with minimal doses of steroids.  相似文献   
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Little evidence exists about the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) with the use of external fixators. We investigated this in a cohort of 207 consecutive patients undergoing 258 elective frame applications by case note review. Case notes were obtained for 84 % of the sample population. The type of surgery, demographic data, thromboembolic risk factors and the incidence of DVT/PE were recorded. One patient experienced DVT (0.39 %) and one a PE (0.39 %). Both were of high risk and had received mechanical and chemical thromboprophylaxis during their inpatient stay. These complications were identified at least 3 months post-operatively. These findings help to more accurately counsel patients undergoing elective frame surgery on the risks of DVT/PE and also contribute to the discussion between surgeons about whether or not extended course chemical thromboprophylaxis would be of overall benefit.  相似文献   
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We performed catheter balloon valvuloplasty (CBV) on 8 stenotic operatively-excised bioprosthetic valves (2 Hancock and 6 Ionescu Shiley). Pathology of valves before CBV included degenerative changes: commissural fusion by mounds of calcific deposits (2 valves), fibrotic and focally calcified leaflets (7 valves) and stiff and thick valves (1 valve). Inflation of the balloon resulted in commissural splitting (2 valves), leaflet cracks and fractures (3 valves). Removal of the deflated balloon catheter was associated with debris dislodgement (3 valves). In one case the valve was unable to close with potential for acute regurgitation. Thus, CBV of bioprosthetic valves can split fused commissures by similar mechanisms as in native valves. CBV may fracture calcific deposits causing acute emboli. It can also disrupt the leaflets causing acute insufficiency. The findings suggest a limited role of CBV in the treatment of stenotic bioprosthetic valves in mitral and aortic position.  相似文献   
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Strains within bone play an important role in the remodelling process and the mechanisms of fracture. The ability to assess these strains in vivo can provide clinically relevant information regarding bone health, injury risk, and can also be used to optimise treatments. In vivo bone strains have been investigated using multiple experimental techniques, but none have quantified 3D strains using non-invasive techniques. Digital volume correlation based on clinical MRI (DVC-MRI) is a non-invasive technique that has the potential to achieve this. However, before it can be implemented, uncertainties associated with the measurements must be quantified. Here, DVC-MRI was evaluated to assess its potential to measure in vivo strains in the talus. A zero-strain test (two repeated unloaded scans) was conducted using three MRI sequences, and three DVC approaches to quantify errors and to establish optimal settings. With optimal settings, strains could be measured with a precision of 200 με and accuracy of 480 με for a spatial resolution of 7.5 mm, and a precision of 133 με and accuracy of 251 με for a spatial resolution of 10 mm. These results demonstrate that this technique has the potential to measure relevant levels of in vivo bone strain and to be used for a range of clinical applications.  相似文献   
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While indices of physical mobility such as gait speed are significant predictors of future morbidity/mortality in the elderly, mechanisms of these relationships are not understood. Relevant animal models of aging and physical mobility are needed to study these relationships. The goal of this study was to develop measures of physical mobility including activity levels and gait speed in Old World monkeys which vary with age in adults. Locomotor behaviors of 21 old ( = 20 yoa) and 24 young ( = 9 yoa) socially housed adult females of three species were recorded using focal sample and ad libitum behavior observation methods. Self-motivated walking speed was 17% slower in older than younger adults. Likewise, young adults climbed more frequently than older adults. Leaping and jumping were more common, on average, in young adults, but this difference did not reach significance. Overall activity levels did not vary significantly by age, and there were no significant age by species interactions in any of these behaviors. Of all the behaviors evaluated, walking speed measured in a simple and inexpensive manner appeared most sensitive to age and has the added feature of being least affected by differences in housing characteristics. Thus, walking speed may be a useful indicator of decline in physical mobility in nonhuman primate models of aging.  相似文献   
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