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1.
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   
2.
目的本文主要研究和探讨护理干预对放疗科头颈部肿瘤放疗患者生活质量的影响。方法将我院2017年2月份至2018年10月份收治的100例头颈部肿瘤放疗患者作为本次研究的对象,在随机原则的指导下把100例患者分为对照组和实验组,每组患者的数量为50例。对照组患者给予常规护理,实验组患者实施护理干预,对两组患者的生活质量、睡眠质量、护理满意度和护理依从性等进行对比分析。结果在生活质量、睡眠质量、护理满意度和护理依从性等方面,组间进行对比分析,实验组都明显优于对照组,P<0.05差异具有统计学意义。结论对头颈部肿瘤放疗患者实施护理干预可以让患者的生活质量、睡眠质量、护理依从性以及护理满意度等都得到显著的改善,从而让患者以一种积极、乐观的心态接受放疗,这对于放疗效果的提高具有重要的作用。总之,这一护理模式应该在临床中进行推广和使用。  相似文献   
3.
目的应用免疫组织化学染色的方法检测硒蛋白P在直肠癌组织中的表达,以探讨其与直肠癌发生的关系及临床意义。方法收集山西大医院2013年6月至2014年5月间行手术治疗并经病理证实的60例直肠癌组织、40例直肠腺瘤组织、40例正常直肠组织,应用SABC法检测上述组织中硒蛋白P的表达情况,结果依据阳性细胞百分率和染色强度进行评价,三组间样本率的比较采用无序行×列表?2检验(α=0.05),两组间样本率的比较采用独立样本?2检验(α=0.016 7),硒蛋白的表达与直肠癌临床病理参数的关系采用四格表?2检验(α=0.05)进行分析。结果硒蛋白P在正常直肠组织、直肠腺瘤组织、直肠癌组织中的表达阳性率分别为82.5%(33/40)、70.0%(28/40)、45.0%(27/60),组间差异有统计学意义(?2=15.680,P<0.001),癌组织与正常组织、腺瘤组织间差异显著(?2=14.063,P<0.001;?2=6.061,P=0.015);硒蛋白的表达与肿瘤大小、是否浸润浆膜有关(P<0.05),与性别、年龄、淋巴结有无转移、肿瘤细胞分化程度、TNM分期无关(P>0.05)。结论硒蛋白在直肠癌中低表达,对直肠癌的发生发展具有重要作用,有望为直肠癌的治疗提供新思路。  相似文献   
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Renal Denervation for Treatment of Cardiac Arrhythmias . It has now been more than a quarter of a century since modulation of the sympathetic nervous system was proposed for the treatment of cardiac arrhythmias of different origins. But it has also been some time since some of the early surgical attempts have been abandoned. With the development of ablation techniques, however, new approaches and targets have been recently introduced that have revolutionized our way of thinking about sympathetic modulation. Renal nerve ablation technology is now being successfully used for the treatment of resistant hypertension, but the indication spectrum might broaden and new therapeutic options might arise in the near future. This review focuses on the possible impact of renal sympathetic system modulation on cardiac arrhythmias, the current evidence supporting this approach, and the ongoing trials of this method in electrophysiological laboratories. We will discuss the potential roles that sympathetic modulation may play in the future.  相似文献   
6.
IntroductionAdenoid cystic carcinoma is the most frequent malignant tumor of the submandibular gland and the minor salivary glands. It is a malignant neoplasm that, despite its slow growth, shows an unfavorable prognosis.ObjectivesThe aim of this study was to perform a systematic review of the literature on Adenoid cystic carcinoma in the head and neck region and its clinicopathological characteristics, with emphasis on the perineural invasion capacity of the tumor.MethodsA systematic search of articles published between January 2000 and January 2014 was performed in the PubMed/MEDLINE, SciELO, Science Direct, and Scopus databases.ResultsNine articles were selected for this systematic review. These demonstrated that the female gender was more often affected and that malignant tumors showed a high rate of distant metastasis, recurrence, and a low survival rate. The presence of perineural invasion ranged from 29.4% to 62.5% and was associated with local tumor recurrence.ConclusionAdenoid cystic carcinoma is commonly characterized by the presence of pain, high rate of recurrence, metastasis, and a low survival rate. Reporting studies with patient follow-up is of utmost importance for a better clinical-pathological understanding and to improve the prognosis of this pathology.  相似文献   
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直肠癌切除前后腹腔冲洗液脱落细胞学对比研究   总被引:1,自引:0,他引:1  
目的研究直肠癌术中腹腔多次冲洗,对于降低患者腹腔内脱落癌细胞阳性率的临床意义。方法对63例直肠癌患者术中腹腔冲洗分6次进行,肿瘤切除前3次,切除后3次;将6次腹腔冲洗液行常规病理学涂片细胞学检查结果进行对比。结果肿瘤切除前,全组患者腹腔冲洗液脱落癌细胞均呈阳性表达。肿瘤切除后第1次腹腔冲洗液脱落癌细胞阳性40例,第2次阳性33例,第3次阳性13例。肿瘤切除后第1次冲洗液的脱落癌细胞阳性结果与切除后第2次冲洗液阳性结果比较,P〉0.05,差异无统计学意义;但第3次冲洗液的脱落癌细胞阳性结果与第2次比较,P〈0.01,差异有统计学意义。结论对直肠癌患者进行术中多次腹腔冲洗可降低腹腔内脱落癌细胞的阳性率。  相似文献   
10.
The aim of this study was to examine the predictors of long-term survival (>24 months) in patients with gall bladder cancer. A retrospective review of 117 cases of gall bladder cancer resected between 1989 and 2000. The resections included 80 simple cholecystectomies and 37 extended procedures. Patients with survival >24 months (n=44) were compared with those having survival <24 months (n=73) for 17 prognostic factors. Overall median survival was 16 months with a 5-year survival of 27%. T status (P=.000) and adjuvant chemoradiotherapy (P=.001) were independent predictors of long-term survival. Survival advantage was seen in T3N+ve disease (P=.007) with extended procedures. Complete (R0) resection was attained in 30 patients with a 5-year survival advantage of 30% as compared with incomplete (R1) resection (P=.0002). Adjuvant chemoradiotherapy improved survival in simple cholecystectomy group (P=.0008) but no advantage was seen after extended procedures. Stage III (P=.001) and node-positive disease (P=.0005) had significant benefit with adjuvant therapy. Poor differentiation and vascular invasion were associated with poor long-term survival. R0 resection was associated with prolonged survival. Extended procedures improved survival in patients with T3N+ve disease. Addition of chemoradiotherapy made significant improvement in long-term survival in stage III and node-positive lesions and in patients undergoing simple cholecystectomy. R0 resection predicted long-term survival in gall bladder cancer. T3 N+ve disease had better survival after extended procedures. Adjuvant chemoradiotherapy improved survival in stage III and node-positive disease. Poor differentiation and vascular invasion were adverse predictors of survival.  相似文献   
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