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Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Progression to cancer typically occurs in a stepwise fashion through worsening dysplasia and ultimately, invasive neoplasia. Established EAC with deep involvement of the esophageal wall and/or metastatic disease is invariably associated with poor long-term survival rates. This guides the rationale of surveillance of Barrett’s in an attempt to treat lesions at an earlier, and potentially curative stage. The last two decades have seen a paradigm shift in management of Barrett’s with rapid expansion in the role of endoscopic eradication therapy (EET) for management of dysplastic and early neoplastic BE, and there have been substantial changes to international consensus guidelines for management of early BE based on evolving evidence. This review aims to assist the physician in the therapeutic decision-making process with patients by comprehensive review and summary of literature surrounding natural history of Barrett’s by histological stage, and the effectiveness of interventions in attenuating the risk posed by its natural history. Key findings were as follows. Non-dysplastic Barrett’s is associated with extremely low risk of progression, and interventions cannot be justified. The annual risk of cancer progression in low grade dysplasia is between 1%-3%; EET can be offered though evidence for its benefit remains confined to highly select settings. High-grade dysplasia progresses to cancer in 5%-10% per year; EET is similarly effective to and less morbid than surgery and should be routinely performed for this indication. Risk of nodal metastases in intramucosal cancer is 2%-4%, which is comparable to operative mortality rate, so EET is usually preferred. Submucosal cancer is associated with nodal metastases in 14%-41% hence surgery remains standard of care, except for select situations.  相似文献   
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IntroductionThe Modena bleeding score is a categorical rating scale that allows the assessment of the surgical field in relation to bleeding during endoscopic surgery. It has recently been presented and validated in the field of endoscopic ear surgery by the present authors. The Modena bleeding score provides five grades for rating the surgical field during endoscopic procedures (from grade 1 ? no bleeding to grade 5 ? bleeding that prevents every surgical procedure except those dedicated to bleeding control).ObjectiveThe aim of this study was to validate the Modena bleeding score in the setting of endoscopic sinus surgery.MethodsFifteen three-minute videos of endoscopic sinus surgery procedures (each containing three bleeding situations) were evaluated by 15 specialists, using the Modena bleeding score. Intra and inter-rater reliability were assessed, and the clinical validity of the Modena bleeding score was calculated using a referent standard.ResultsThe data analysis showed an intra-rater reliability ranging from 0.6336 to 0.861. The inter-rater reliability ranged from 0.676 to 0.844. The clinical validity was α = 0.70; confidence limits: 0.64 ? 0.75, corresponding to substantial agreement.ConclusionThe Modena bleeding score is an effective method to score bleeding during endoscopic sinus surgery. Its application in future research could facilitate the performance and efficacy assessment of surgical techniques, materials or devices aimed to bleeding control during endoscopic sinus surgery.  相似文献   
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目的探讨多元化联合教学模式在超声引导下疼痛介入治疗教学中的应用效果。方法选择2018年1月至2020年12月在北京大学第三医院疼痛科进修的30名医师作为研究对象,将其分为对照组与观察组;对照组采用常规教学模式;观察组采用多元化联合教学模式,比较两组医师技能考核成绩、教学质量评分和满意度评分。结果观察组医师技能考核成绩优良率为93.3%,高于对照组的73.3%(P<0.05);观察组医师对基础理论知识掌握、临床思维能力的提高、学习兴趣的激发、疾病诊治能力的提高4个方面的评分均高于对照组(P<0.01)。结论多元化联合教学模式可促进超声引导下疼痛介入治疗技能的提高,有利于提高学员的综合临床能力。  相似文献   
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目的:总结后颅窝正常和异常的胎儿小脑及小脑蚓部的矢状面的声像学特征,了解小脑细微结构的改变与胎儿畸形的关系。  相似文献   
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