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11.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
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《Urological Science》2015,26(2):144-146
Hydronephrosis with an undetermined pathology is a common condition detected in imaging studies. In urological clinical practice, it is a persistent dilemma to predict whether this condition will progress to result in the deterioration of renal function. Perfusion pressure flow study of the upper urinary tract, known as the Whitaker test, provides an alternative diagnostic tool for solving this condition. Perfusion pressure flow study has been criticized for its invasiveness, nonphysiological approach, and inconsistency in predicting outcomes. However, it continues to be used to evaluate difficult or equivocal cases and to provide an objective assessment of the upper urinary tract. 相似文献
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目的通过检查有龋及无龋母亲的口腔卫生状况,并通过随访收集其婴儿1个月(1月龄)及6个月(6月龄)的唾液样本测序分析,观察母亲患龋情况对其婴儿口腔微生物多样性的影响。方法通过筛查收集1月龄婴儿的唾液样本;于首次采样时记录母亲的口腔卫生状况,根据母亲患龋情况将婴儿分为母亲有龋组(简称有龋组)和母亲无龋组(简称无龋组),跟踪随访至婴儿6个月时再次收集唾液样本。通过高通量测序的方法,分析婴儿不同月龄微生物多样性的变化。结果本研究随访受试者10例(男6例,女4例),其中有龋组7例,无龋组3例,各组间的微生物群落多样性Shannon指数均无显著性差异(P>0.05)。无龋组婴儿1月龄至6月龄时微生物群落的物种组成有较大变化;有龋组婴儿在1月龄和6月龄时组内各样本间物种组成均差异较大;1月龄时两组微生物群落较相似,而至6月龄时两组婴儿唾液的物种组成已开始发生变化。结论有龋组婴儿口腔内菌群多样性总体高于无龋组,在1月龄至6月龄间婴儿口腔内微生物物种的多样性及丰度均有了不同程度的提高。 相似文献
14.
面对来势汹汹的新型冠状病毒肺炎(COVID-19),如何能够正确、快速诊断和筛检出确诊病例显得尤为重要,国内诸多科技工作者都在积极开展相关的诊断试验研究。本文回顾了目前正在开展的十余项诊断试验的注册信息,针对其中存在的共性问题进行了讨论,重点阐述了如何使用PICOS原则构造COVID-19诊断试验的研究问题,还对金标准的设置、受试者的代表性、样本量计算和同步、独立、盲法的测定等诊断试验的设计要点进行了详细说明。旨在为广大研究者提供开展COVID-19诊断试验的设计建议,帮助研究者在顶层设计阶段减少、避免偏倚,完成高质量的临床研究,为临床诊疗提供循证医学证据。 相似文献
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目的: 分析探讨加速康复外科(ERAS)理念在脊柱结核围手术期护理应用中的效果。 方法: 收集青岛市胸科医院外科2017年7月至2020年6月收治的147例脊柱结核患者。其中,2017年7月至2018年12月收治的68例脊柱结核手术患者围手术期应用常规护理,作为对照组;2019年1月至2020年6月收治的79例脊柱结核手术患者在常规护理措施基础上融入了ERAS理念,作为ERAS组。比较两组患者的引流管拔除、最初下床进行功能锻炼、最初自主排尿的时间,术后72h疼痛(采用视觉模拟评分法)评分,住院天数,恶心呕吐、肺部感染、药物性肝损伤的发生率,以及患者满意度的差异。 结果: 与对照组相比,ERAS组患者引流管拔除时间[6.00(4.00,8.00)d和8.00(7.00,8.00)d;W=4321.000,P<0.001]、最初下床进行功能锻炼时间[2.00(2.00,4.00)d和5.50(4.25,6.00)d;W=3376.000,P<0.001]、首次在床上自主排尿时间[5.00(3.00,6.00)h和9.00(7.00,9.00)h;W=3369.000,P<0.001]、术后72h疼痛评分[3.00(2.00,4.00)分和5.00(5.00,6.00)分;W=4078.500,P<0.001]、住院总天数[19.00(18.00,21.00)d和22.00(19.00,27.00)d;W=4791.500,P<0.001]均有所下降,差异均有统计学意义。与对照组相比,ERAS组术后恶心呕吐发生率[7.6%(6/79)和19.1%(13/68);χ2=4.311,P=0.038]、肺部感染发生率[2.5%(2/79)和11.8%(8/68);χ2=4.914,P=0.027]、药物性肝损伤发生率[1.3%(1/79)和13.2%(9/68),χ2=8.258,P=0.004]均有所下降,差异均有统计学意义。ERAS组患者满意度高于对照组[96.2%(76/79)和85.3%(58/68),χ2=7.100,P=0.008],差异有统计学意义。 结论: ERAS理念应用于脊柱结核围手术期护理可以加速患者的康复,减少并发症的发生,提高患者的满意度。 相似文献
17.
ObjectiveThis study used a prospective cohort study to observe the effect of triple-negative breast cancer on the 2-year disease-free survival rate with or without “TCM formula”.MethodsFrom November 1 st, 2016, the first patient was enrolled in the cohort study. A total of 356 patients were enrolled on January 30, 2019. Among them, 154 cases were followed up for 2 years. During the follow-up, there were 6 cases of shedding, so 6 cases were affected. A total of 148 cases were included in the analysis, including 73 in the exposed group and 75 in the non-exposed group. The exposed group was given “TCM formula” on the basis of standardized treatment, and the non-exposed group was treated with simple triple-negative breast cancer. The two groups visited each of the three months. The interview included safety examination (hematology and imaging). The endpoint was the difference in 2-year invasive disease-free survival between the exposed and non-exposed groups and the safety of the “TCM formula”.ResultsThere were 6 cases of shedding during the experiment and the shedding rate was 3.9 %. The 2-year rate of invasive disease-free survival in the exposed team was 88.7 % and the non-exposed group was 82.5 %. Logistic multivariate regression analysis predicted that “TCM formula” could reduce the disease-related recurrence and metastasis rate by 11 % (OR = 0.89, 95 % CI 0.37−0.956, P<0.05). Through K–M survival analysis, TNBC patients with age ≤35 years and regional lymph node stage N1 may be the benefit group of “TCM formula”(P<0.05). During the study, the incidence of total adverse events was 8.2 % in the exposed group, mainly manifested as stomach discomfort, diarrhea, and hepatocyte damage.Conclusion1. In the exposed group, the two-year rate of invasive disease-free survival increased by 6.2 % compared with the non-exposed group(P>0.05). 2. According to K–M survival analysis, TNBC patients with age ≤35 years and regional lymph node metastasis to N1 may be potential beneficiaries of “TCM formula”. 3. “TCM Formula” is safe and tolerable to most patients. 相似文献
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