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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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目的:运用软硬腭前移的手术方法扩大鼻咽下口,改善因鼻咽部狭小致阻塞性睡眠呼吸暂停综合征患者的呼吸暂停症状。方法:手术切除硬腭后份使其缩短、悬雍垂软腭成形并将软腭拉向前,扩大鼻咽下口。结果:患者术后自觉症状及客观评价疗效满意。结论:软硬腭前移鼻咽下口扩大显著改善鼻咽下口狭小导致的阻塞性睡眠呼吸暂停患者的症状。  相似文献   
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Both ultrashort echo-time STEAM and MEGA-PRESS-edited spectroscopy were used to validate noninvasive quantification of vitamin C (ascorbate) in the developing rat brain, where changes in ascorbate concentration have been reported. Despite strong overlap with resonances from glutamine, glutamate, glutathione, and macromolecules, reliable quantification of ascorbate (Cramer-Rao lower bounds<0.2 micromol/g) by LCModel analysis of STEAM (TE=2 ms) spectra was possible at 9.4 T. Ascorbate concentrations quantified from the STEAM spectra were in very good agreement with concentrations calculated from fully resolved ascorbate resonances in MEGA-PRESS-edited spectra measured from identical volumes of interest. Ascorbate concentrations measured using STEAM decreased with increasing postnatal rat age, in agreement with published brain ascorbate concentrations measured in vitro using high-performance liquid chromatography (HPLC).  相似文献   
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高龄老年股骨转子间骨折的手术治疗   总被引:1,自引:1,他引:0  
2000年1月~2005年1月,我科在C臂X线机下行闭合复位、有限小切口切开、短臂螺钉内固定治疗高龄老年股骨转子间骨折94例,取得了较好疗效。1材料与方法1.1病例资料本组94例,男42例,女52例,年龄80~97岁(80~89岁84例,90岁以上10例)。骨折按Evans分型:Ⅰ型26例,Ⅱ型31例,Ⅲ型29例,Ⅳ型8例。所有患者均存在不同程度骨质疏松和退行性骨关节病,其中79例有并存症,2种以上并存症者47例,个别病例最多并存症达5种。各种并存症中高血压41例,呼吸系统疾病21例,脑血管疾病15例,冠心病21例,糖尿病14例,泌尿系疾病11例,消化系统疾病9例,五官科疾病12例,肿瘤2…  相似文献   
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We report on a Thai family with dominantly inherited malformation syndrome with upper limb anomalies, short stature, quadricuspid aortic valve, and minor craniofacial anomalies. The affected individuals comprised a mildly affected mother, a moderately affected daughter, and a most severely affected son. The daughter and son had short stature. The craniofacial abnormalities comprised frontal bossing, hypoplastic nasal bones, depressed nasal bridge, and broad nasal alae. The upper limb defects varies among the patients, ranging from radial ray defects in the mother through radial and ulnar ray defects with unilateral humeral hypoplasia in the daughter to radial ray defects with severe oligodactyly and bilateral humeral hypoplasia in the son. All patients in this family had hypoplasia of the shoulder girdle and resembled what is observed in many families with Holt‐Oram syndrome. Moreover, the son showed quadricuspid aortic valve with mild aortic regurgitation. However, the present family did not show any mutation of the TBX5 gene, a disease‐causing gene of Holt‐Oram syndrome. The present family deserves further investigation on other genes that play a role in the development of the upper limbs, particularly of radial rays. © 2002 Wiley‐Liss, Inc.  相似文献   
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短串联重复序列HumFGA、D3S1359的法医学应用研究   总被引:1,自引:0,他引:1  
对短串联重复序列(short tandem repeats,STR)的两个高多态位点HumFGA(human alpha fibrinogen,人类α-纤维蛋白原基因)、D3S1359的法医学应用进行研究,并通过实际检测案件统计结果进行评估。实验结果表明:两位点灵敏度高,分别为0.2、0.5ngDNA;同一性和可重复性均较理想;种属特异性好,常见动物未发现扩增产物,仅灵长类动物(黑叶猴和猕猴)有扩增条带;复合扩增体系效果良好;在352次减数分裂中,D3S1359未发现突变,HumFGA检测到1次,突变率为0.28%;实际案件统计和应用结果也显示两位点是多态性高,实用性强的两个遗传标记系统。HumFGA和D3S1359在法医学个人识别与亲子鉴定案例中有较大应用价值。  相似文献   
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D16S539等5个短串联重复序列基因座遗传多态性分析   总被引:1,自引:1,他引:0  
目的 探讨河南汉族群体 D16S53 9、D7S82 0、D13 S3 17、D8S1179和 D2 1S11等 5个基因座基因频率 ,获得群体遗传学数据。方法 随机抽取 2 0 9名河南汉族群体无血缘关系个体的静脉血 ,柠檬酸抗凝剂抗凝 ,酚 -氯仿法提取 DNA ,应用 PCR技术扩增上述 5个 STR基因座 ,聚丙烯酰胺凝胶垂直板电泳分型。结果  2 0 9名个体中 D16S53 9、D7S82 0、D13 S3 17、D8S1179和 D2 1S11等 5个基因座分别检出 7、8、8、10、15个等位基因 ,基因型分布符合 Hardy-Weinberg平衡。 5个基因座的杂合度分别为 0 .790 7、0 .80 56、0 .7914、0 .82 3 9、0 .80 46,多态信息含量分别为 0 .7712、0 .780 1、0 .7694、0 .80 0 9、0 .7816,个人识别能力在 0 .9416、0 .93 67、0 .9511、0 .9546、0 .93 0 8,非父排除概率分别为 0 .610 6、0 .6179、0 .614 5、0 .70 2 2、0 .6712。结论  5个 STR基因座具有高度多态性遗传标记特征 ,在群体遗传学研究和法医学应用中具有较高的价值  相似文献   
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