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121.
Intracellular fat accumulation is a common feature of liver disease. Steatosis is the histological hallmark of non-alcoholic fatty liver disease (NAFLD) but also may occur with alcohol abuse, viral hepatitis, HIV and genetic lipodystrophies, and chemotherapy. This condition is common in the Western population and is typically associated with obesity and the metabolic syndrome. Early diagnosis and early treatment of NAFLD are important to prevent the development of end-stage liver disease and cancer. In addition, liver fat is a risk factor for postoperative complications after liver resection and transplantation. MRI has become a primary modality to assess hepatic steatosis, both qualitatively and quantitatively. In this article we discuss various MRI methods for evaluation of hepatic steatosis.  相似文献   
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Type 1 diabetes (T1D) is a metabolic disease that is initiated by the autoimmune destruction of pancreatic insulin-producing beta cells that is accompanied by the development of antigen-specific antibodies and cytotoxic T lymphocytes (CTLs). Several studies have shown that vaccination with diabetic autoantigens provides some protection against this process. In this report we describe a new oral vaccine that utilizes live attenuated Salmonella for simultaneous delivery of autoantigens in conjunction with immunomodulatory cytokine genes to immune cells in the gut mucosa. Recent data showed that live attenuated Salmonella is a safe, simple and effective vector for expression of antigens and cytokines by antigen-presenting cells (APCs) of gut-associated lymphatic tissue (GALT). This novel strategy was tested by fusion of the diabetic autoantigen preproinsulin with Salmonella secretory effector protein (SseF) of pathogenicity island-2 (SPI2). In this way the autoantigen is only expressed inside the host immune cells and translocated to the host cell cytosol. In addition Salmonella was used to deliver the gene for the immunomodulatory cytokine transforming growth factor beta (TGFβ) for host cell expression. Oral co-vaccination of 8 week-old non-obese diabetic (NOD) mice with three weekly doses of both the autoantigen and cytokine significantly reduced the development of diabetes, improved the response to glucose challenge, preserved beta cell mass, and reduced the severity of insulitis compared with controls and autoantigen alone. Combination therapy also resulted in increased circulating levels of IL10 four weeks post-vaccination and IL2 for 12 weeks post-vaccination, but without effect on proinflammatory cytokines IL6, IL12(p70), IL17 and IFNγ. However, in non-responders there was a significant rise in IL12 compared with responders. Future studies will examine the mechanism of this vaccination strategy in more detail. In conclusion, Salmonella-based oral vaccines expressing autoantigens combined with imunomodulatory cytokines appears to be a promising therapy for prevention of T1D.  相似文献   
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Ingested foreign bodies are a fairly common otorhinolaryngological emergencies encountered in Malaysia. The vast majority of these foreign bodies are fish bones which most commonly are impacted at the level of the cricopharynx. Rarely, however, a foreign body may migrate extraluminally and may even extrude subcutaneously. We report a rare occurrence where a fish bone not only migrated extraluminally, it was found to have migrated into the common carotid artery and the internal jugular vein and required surgical removal.  相似文献   
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A 72-year-old hypertensive man with diabetes had a previously undiagnosed pattern of coronary artery distribution: the ramus intermedius from the left sinus, and the separate origin of the left anterior descending artery, left circumflex artery and right coronary artery from the right sinus. A unique form of branching, a hybrid distribution, was also noted: the left anterior descending artery giving off a right ventricular branch and septals arising from the ramus. No intervention was planned due to the minimal disease observed with angiography and the absence of an interarterial course.  相似文献   
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BACKGROUND: There is a paucity of data regarding the long-term outcome of patients operated for ventricular septal defect with severe pulmonary arterial hypertension and elevated pulmonary vascular resistance. METHODS AND RESULTS: We evaluated the long-term follow-up results of a selected cohort of patients with nonrestrictive ventricular septal defect and elevated pulmonary vascular resistance (>6 Wood units). Thirty-eight patients, median age 7.5 years (range 6 months-27 years), with nonrestrictive ventricular septal defect with severe pulmonary hypertension were operated between 1985 and 1996 at our institute. Preoperative pulmonary vascular resistance, ratio of pulmonary blood flow to systemic blood flow, and ratio of pulmonary vascular resistance to systemic vascular resistance were 7.63+/-1.8 Wood units, 1.9+/-0.48, and 0.41+/-0.12, respectively. The majority (68.4%) had perimembranous ventricular septal defect. Thirty patients (79%) had a good outcome and were asymptomatic at a mean follow-up of 8.7 years, with significant reduction in pulmonary artery pressures. Eight patients (21%) had a poor outcome, which included 5 immediate postoperative deaths, 1 late death and 2 surviving patients with persistent severe pulmonary arterial hypertension. There was no significant difference regarding hemodynamic parameters at baseline between those who had a good outcome and those who did not. Eleven patients with a preoperative pulmonary blood flow to systemic blood flow ratio of <2:1. who had a good outcome following surgery, underwent repeat catheterization at follow-up. There was a significant reduction in their mean pulmonary vascular resistance (8.03+/-1.4 v. 4.16+/-1.6 Wood units, p=0.001) and pulmonary vascular resistance to systemic vascular resistance ratio (0.41+/-0.12 v. 0.19+/-0.06, p=0.05). CONCLUSIONS: The late results of surgery on this selected group of patients with nonrestrictive ventricular septal defect with high pulmonary vascular resistance are encouraging. Operative correction of the ventricular septal defect should be actively considered in all children presenting with nonrestrictive ventricular septal defect with a significant left-to-right shunt, despite moderately elevated pulmonary vascular resistance. Even among older patients with ventricular septal defect and moderately elevated pulmonary vascular resistance, there is a specific group that does well after operation.  相似文献   
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