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1.
Diabetic retinopathy (DR) is one of the most important complications of diabetes. Accurate segmentation of DR lesions is of great importance for the early diagnosis of DR. However, simultaneous segmentation of multi-type DR lesions is technically challenging because of 1) the lack of pixel-level annotations and 2) the large diversity between different types of DR lesions. In this study, first, we propose a novel Poisson-blending data augmentation (PBDA) algorithm to generate synthetic images, which can be easily utilized to expand the existing training data for lesion segmentation. We perform extensive experiments to recognize the important attributes in the PBDA algorithm. We show that position constraints are of great importance and that the synthesis density of one type of lesion has a joint influence on the segmentation of other types of lesions. Second, we propose a convolutional neural network architecture, named DSR-U-Net++ (i.e., DC-SC residual U-Net++), for the simultaneous segmentation of multi-type DR lesions. Ablation studies showed that the mean area under precision recall curve (AUPR) for all four types of lesions increased by >5% with PBDA. The proposed DSR-U-Net++ with PBDA outperformed the state-of-the-art methods by 1.7%-9.9% on the Indian Diabetic Retinopathy Image Dataset (IDRiD) and 67.3% on the e-ophtha dataset with respect to mean AUPR. The developed method would be an efficient tool to generate large-scale task-specific training data for other medical anomaly segmentation tasks.  相似文献   
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《Cancer radiothérapie》2022,26(3):502-516
The aim of the review was to present the current literature status about replanning regarding anatomical and dosimetric changes in the target and OARs in the head and neck region during radiotherapy, to discuss and to analyze factors influencing the decision for adaptive radiotherapy of head and neck cancer patients. Significant progress has been made in head and neck patients’ evaluation and qualification for adapted radiotherapy over the past ten years. Many factors leading to anatomical and dosimetric changes during treatment have been identified. Based on the literature, the most common factors triggering re-plan are weight loss, tumor and nodal changes, and parotid glands shrinkage. The fluctuations in dose distribution in the clinical area are significant predictive factors for patients’ quality of life and the possibility of recovery. It has been shown that re-planning influence clinical outcomes: local control, disease free survival and overall survival. Regarding literature studies, it seems that adaptive radiotherapy would be the most beneficial for tumors of immense volume or those in the nearest proximity of the OARs. All researchers agree that the timing of re-planning is a crucial challenge, and there are still no clear consensus guidelines for time or criteria of re-planning. Nowadays, thanks to significant technological progress, the decision is mostly made based on observation and supported with IGRT verification. Although further research is still needed, adaptive strategies are evolving and now became the state of the art of modern radiotherapy.  相似文献   
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The right and left ventricle of heart are intimately connected by anatomical and functional links. Hence, acute changes in cardiac geometry and function can modify the performance and physiology of both sides of the heart, influencing each other. After a brief overview of the anatomy and related imaging techniques for the study of right ventricular function, we report a review-on the interesting correlation of acute anterior myocardial infarction and right ventricular function, very often underestimated.  相似文献   
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培养“医信融合”复合型医学人才是医学高等教育在新时代信息技术发展背景下的历史使命。在引入“医信融合”教育理念的基础上,提出“医信融合”教育的人才培养目标及其内容体系,并据此构建了“医信融合”人才培养质量评价指标,提出了培养效果评价方法。介绍“医信融合”教育人才培养效果的评价方法,对山西医科大学“医信融合”教学效果进行实证分析,从而为“医信融合”教育实践提供借鉴。  相似文献   
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细胞周期蛋白E1(Cyclin E1,CCNE1)基因扩增是卵巢高级别浆液性癌(high-grade serous ovarian carcinoma,HGSOC)最常见的拷贝数变异之一,扩增率为20%左右。CCNE1基因扩增不仅参与HGSOC的早期癌前病变,促进恶性肿瘤的发生、发展,还可引起细胞周期紊乱和染色体不稳定,从而增加HGSOC的铂类耐药性和复发率,最终导致患者的化疗效果不佳和预后较差。为改善CCNE1扩增的HGSOC患者的预后和生活质量,在暂时没有CCNE1扩增的HGSOC的靶向治疗药物的情况下,使用细胞周期蛋白依赖性激酶2(cyclin-dependent kinases 2,CDK2)小分子抑制剂或者多腺苷二磷酸核糖聚合酶[poly (ADP-ribose) polymerase,PARP]抑制剂与其他药物联合治疗,一定程度上能有效地抑制肿瘤细胞的增殖活性,促进肿瘤细胞死亡。因此,从CCNE1扩增对HGSOC的早期发病机制的影响和产生铂类耐药的角度上来说,CCNE1基因有望成为HGSOC的潜在治疗靶标和预后评价生物学指标,在改善患者的治疗和预后方面具有重要意义。  相似文献   
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目的:探讨早产儿消化道穿孔的病因,分析影响早产儿消化道穿孔短期预后不良的危险因素。方法:回顾性分析山西省 儿童医院新生儿外科2015年1月—2021 年5月诊治的89 例早产儿消化道穿孔的临床资料。根据术后3 个月时结局分为生存 组和预后不良组。比较两组术前、术中及术后与早产儿消化道穿孔预后不良相关的因素,采用Logistic 回归分析筛选早产儿消 化道穿孔预后不良的危险因素。结果:早产儿消化道穿孔的病死率为25.84%,坏死性小肠结肠炎(NEC)和胃壁肌层缺损是早产 儿消化道穿孔常见的病因。单因素分析显示生存组患儿从发现气腹至手术时间在8 h 之内的比例显著高于预后不良组 (χ2=15.22,P<0.01)。预后不良组合并脓毒性休克的比例显著高于生存组(χ2=33.19,P<0.01)。预后不良组术后合并需非计划二次 手术的并发症比例显著高于生存组(χ2=7.24,P<0.01)。Logistic 回归分析显示脓毒性休克(OR=0.06,95%CI:0.02~0.21,P<0.01)和 气腹至手术时间大于8 h(OR=0.23,95%CI:0.07~0.81,P<0.05)是早产儿消化道穿孔短期预后不良的危险因素。结论:NEC 和胃 壁肌层缺损是早产儿消化道穿孔的主要病因,脓毒性休克和从气腹发生至手术时间大于8 h 是早产儿消化道穿孔短期预后 不良的危险因素。  相似文献   
10.
Rapid industrial and technological development has impacted ecosystem homeostasis strongly. Arsenic is one of the most detrimental environmental toxins and its management with chelating agents remains a matter of concern due to associated adverse effects. Thus, safer and more effective alternative therapy is required to manage arsenic toxicity. Based on existing evidence, native and indigenous plant-based active biomolecules appear as a promising strategy to mitigate arsenic-induced toxicity with an acceptable safety profile. In this regard, various phytochemicals (flavonoids and stilbenoids) are considered important classes of polyphenolic compounds with antioxidant and chelation effects, which may facilitate the removal of arsenic from the body more effectively and safely with regard to conventional approaches. This review presents an overview of conventional chelating agents and the potential role of flavonoids and stilbenoids in ameliorating arsenic toxicity. This report may provide a roadmap for identifying novel prophylactic/therapeutic strategies for managing arsenic toxicity.  相似文献   
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