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1.
We present an automated approach to detect and longitudinally track skin lesions on 3D total-body skin surface scans. The acquired 3D mesh of the subject is unwrapped to a 2D texture image, where a trained objected detection model, Faster R-CNN, localizes the lesions within the 2D domain. These detected skin lesions are mapped back to the 3D surface of the subject and, for subjects imaged multiple times, we construct a graph-based matching procedure to longitudinally track lesions that considers the anatomical correspondences among pairs of meshes and the geodesic proximity of corresponding lesions and the inter-lesion geodesic distances.We evaluated the proposed approach using 3DBodyTex, a publicly available dataset composed of 3D scans imaging the coloured skin (textured meshes) of 200 human subjects. We manually annotated locations that appeared to the human eye to contain a pigmented skin lesion as well as tracked a subset of lesions occurring on the same subject imaged in different poses. Our results, when compared to three human annotators, suggest that the trained Faster R-CNN detects lesions at a similar performance level as the human annotators. Our lesion tracking algorithm achieves an average matching accuracy of 88% on a set of detected corresponding pairs of prominent lesions of subjects imaged in different poses, and an average longitudinal accuracy of 71% when encompassing additional errors due to lesion detection. As there currently is no other large-scale publicly available dataset of 3D total-body skin lesions, we publicly release over 25,000 3DBodyTex manual annotations, which we hope will further research on total-body skin lesion analysis.  相似文献   
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PurposeTo investigate the safety of yttrium-90 radioembolization in combination with checkpoint inhibitor immunotherapy for the treatment of hepatocellular carcinoma (HCC).Materials and MethodsThis single-center retrospective study included 26 consecutive patients with HCC who received checkpoint inhibitor immunotherapy within 90 days of radioembolization from April 2015 to May 2018. Patients had preserved liver function (Child-Pugh scores A–B7) and either advanced HCC due to macrovascular invasion or limited extrahepatic disease (21 patients) or aggressive intermediate stage HCC that resulted in earlier incorporation of systemic immunotherapy (5 patients). Clinical documentation, laboratory results, and imaging results at 1- and 3-month follow-up intervals were reviewed to assess treatment-related adverse events and treatment responses.ResultsThe median follow-up period after radioembolization was 7.8 months (95% confidence interval [CI], 5.6–11.8). There were no early (30-day) mortality or grades 3/4 hepatobiliary or immunotherapy-related toxicities. Delayed grades 3/4 hepatobiliary toxicities (1–3 months) occurred in 2 patients in the setting of HCC disease progression. One patient developed pneumonitis. The median overall survival from first immunotherapy was 17.2 months (95% CI, 10.9–23.4). The median overall survival from first radioembolization was 16.5 months (95% CI, 6.6–26.4). From first radioembolization, time to tumor progression was 5.7 months (95% CI, 4.2–7.2), and progression-free survival was 5.7 months (95% CI, 4.3–7.1).ConclusionsRadioembolization combined with checkpoint inhibitor immunotherapy in cases of HCC appears to be safe and causes limited treatment-related toxicity. Future prospective studies are needed to identify the optimal combination treatment protocols and evaluate the efficacy of combination therapy.  相似文献   
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《Vaccine》2020,38(1):20-28
During the last few decades, maternal immunization as a strategy to protect young infants from infectious diseases has been increasingly recommended, yet some issues have emerged. Studies have shown that for several vaccines, such as live attenuated, toxoid and conjugated vaccines, high maternal antibody titers inhibit the infant’s humoral immune response after infant vaccination. However, it is not clear whether this decreased antibody titer has any clinical impact on the infant’s protection, as the cellular immune responses are often equally important in providing disease protection and may therefore compensate for diminished antibody levels. Reports describing the effect of maternal antibodies on the cellular immune response after infant vaccination are scarce, probably because such studies are expensive, labor intensive and utilize poorly standardized laboratory techniques. Therefore, this review aims to shed light on what is currently known about the cellular immune responses after infant vaccination in the presence of high (maternal) antibody titers both in animal and human studies. Overall, the findings suggest that maternally derived antibodies do not interfere with the cellular immune responses after infant vaccination. However, more research in humans is clearly needed, as most data originate from animal studies.  相似文献   
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嗜神经侵袭是肿瘤通过神经扩散与转移的一种独特的生物学行为,与复发、转移、预后密切相关。随着研究的不断深入,人们普遍认识到嗜神经侵袭的临床意义。但由于头颈部肿瘤发病率相对较低,不同解剖部位、不同病理类型嗜神经发生率各不相同,故缺乏高级别的循证医学证据。目前嗜神经侵袭的病理学机制尚未完全阐明,也无针对神经侵犯的特异性治疗手段,因此头颈部肿瘤嗜神经侵袭的治疗对于临床医师是一个巨大的挑战。本文就头颈部恶性肿瘤中嗜神经侵袭的临床诊治现状做一综述。  相似文献   
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目的 利用MRI技术连续采集头颈部肿瘤患者吞咽时图像,观察并测量软腭、舌、喉的运动规律及最大活动度。方法 随机选取2018年7月-10月在中国医学科学院肿瘤医院接受调强放疗的原发头颈部恶性肿瘤20例患者,其中男17例、女3例,中位年龄58.5岁(28~78岁)。20例患者中鼻咽癌7例,口腔癌3例,口咽癌5例,下咽癌3例,鼻腔鼻旁窦2例。根据AJCC第八版分期Ⅰ-Ⅱ期患者2例,Ⅲ期8例,Ⅳ期10例。结果 吞咽时软腭向上移动移动距离为(1.06±0.31) cm且服从正态分布,向后移动距离为(0.83±0.24) cm且近似正态分布。舌体向后移动距离为(0.77±0.22) cm,且服从正态分布。含压舌板行图像采集患者舌上移位移为0,无压舌板患者舌体中位上移距离为1.23 cm (0.59~1.41 cm)。喉向上移动距离为(1.14±0.22) cm且服从正态分布,向前移动的中位距离为0.4 cm (0.27~0.90 cm)。结论 吞咽运动有可能发生于头颈部肿瘤患者放疗过程中,并引起大体肿瘤体积(GTV)及周围正常组织移动;因此在制定放疗计划时应注意GTV至PGTV的个体化外放距离,以保证肿瘤处方剂量。  相似文献   
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目的 探讨剂量组学在预测肺癌根治性放疗患者放射性肺炎发生中的应用潜能。方法 回顾性收集行根治性放疗的314例肺癌患者的临床资料、放疗剂量文件、定位及随访CT图像,根据临床资料及影像学随访资料对放射性肺炎进行分级,提取全肺的剂量组学特征,构建机器学习模型。应用1000次自助抽样法(bootstrap)的最小绝对值收敛和选择算子嵌套逻辑回归(LASSO‐LR)及1000次bootstrap的赤池信息量准则(AIC)向后法筛选与放射性肺炎相关的剂量组学特征,随机按照7∶3划分为训练集及验证集,应用逻辑回归建立预测模型,并应用ROC曲线及校正曲线评价模型的性能。结果 共提取120个剂量组学特征,经LASSO‐LR降维筛选得到12个特征进入“特征池”,再经过AIC向后法筛选,最终筛选出6个剂量组学特征进行模型构建,训练集AUC为0.77(95%CI为0.65~0.87),独立验证集AUC为0.72(95%CI为0.64~0.81)。结论 利用剂量组学建立的预测模型具有预测放射性肺炎发生的潜力,但仍需继续纳入多中心数据及前瞻性数据进一步挖掘剂量组学的应用潜能。  相似文献   
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探讨高龄直肠癌患者腹会阴联合切除术(APR)后会阴切口并发症发生的相关危险因素。方法采用回顾性病例对照研究的方法,分析中国医学科学院肿瘤医院结直肠外科2007年1月至2018年9月行APR的72例高龄(≥80岁)直肠癌患者的临床病理资料。采用单因素和多因素分析确定影响高龄直肠癌患者APR后会阴切口并发症发生的危险因素。结果72例患者中,男47例,女25例,年龄为(81.8±1.8)岁。术后会阴切口并发症发生率为23.6%(17/72),其中切口感染5例,切口脂肪液化4例,切口延迟愈合8例。所有患者均顺利出院,无围手术期死亡病例。单因素分析显示,术前血清白蛋白<35 g/L、术中置入氟尿嘧啶缓释剂/洛铂冲洗液、盆底修复、糖尿病和冠心病与高龄患者APR术后会阴切口并发症的发生均有关(均P<0.05)。多因素分析显示,未行盆底修复(OR=0.17,95%CI为0.04~0.82;P=0.027)和糖尿病(OR=4.32,95%CI为1.05~17.81;P=0.043)为高龄直肠癌患者APR后会阴切口发生的独立危险因素。结论行APR的高龄直肠癌患者应尽可能保留盆底腹膜,并予以关闭。围手术期血糖监测也是预防会阴切口并发症发生的有力保障。  相似文献   
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目的:探讨超高CD34+采集的动员方案后序贯二次自体造血干细胞移植治疗难治性霍奇金淋巴瘤的疗效和安全性。方法:对1例经过多疗程一线、二线、新药、免疫等均难治的霍奇金淋巴瘤患者,予以IA+C方案化疗+G-CSF动员干细胞后采集出超高水平CD34+细胞,之后行自体造血干细胞移植,移植后获得完全缓解,再予序贯第二次自体造血干细胞移植进行巩固治疗。结果:总计输注单个核细胞数13.67×108/kg,CD34+细胞48.68×106/kg,第一次自体造血干细胞移植术后第7天造血功能恢复,复查全身PET-CT提示获得完全缓解,第二次自体造血干细胞移植术后第8天造血功能恢复,两次自体造血干细胞移植相关并发症均在可控范围内。结论:超高CD34+细胞采集的IA+C方案化疗+G-CSF动员可以让患者有机会进行多次自体造血干细胞移植,是临床动员的创新方案。对于难治性霍奇金淋巴瘤,序贯二次自体造血干细胞移植可达到更深层次缓解,且安全性较高,延长患者无疾病生存期及总生存期,为难治性霍奇金淋巴瘤治疗提供更多临床依据。  相似文献   
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