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BackgroundSome chronic obstructive pulmonary disease (COPD) patients develop hypoxemia with disease progression, with some even requiring long-term oxygen therapy (LTOT). Lung function, especially diffusing capacity, and the annual decline in PaO2, are reported to be predictive factors of chronic respiratory failure. However, the association between lung morphometry evaluated using computed tomography (CT) images and LTOT initiation is unknown.MethodsWe retrospectively evaluated the relationship between clinical indices, including pulmonary function, body mass index (BMI), and CT parameters, at baseline and LTOT initiation in two prospective COPD cohorts. In the Nara Medical University cohort (n = 76), the low attenuation area (LAA) and its fractal dimension (fractal D) were adapted as the indices for parenchymal destruction in CT images. The association between these CT measurements and LTOT initiation was replicated in the Kyoto University cohort (n = 130).ResultsIn the Nara Medical University cohort, lower BMI (hazard ratio [HR]:0.70, p = 0.006), lower % diffusing capacity (%DLCO) (HR: 0.92, p = 0.006), lower %DLCO/VA (HR, 0.90, p = 0.008), higher RV/TLC (HR, 1.26, p = 0.012), higher LAA% (HR: 1.18, p = 0.001), and lower fractal D (HR: 3.27 × 10?8, p < 0.001) were associated with LTOT initiation. Multivariate analysis in the Kyoto University cohort confirmed that lower %DLCO and lower fractal D were independently associated with LTOT initiation, whereas LAA% was not.ConclusionFractal D, which is the index for morphometric complexity of LAA in CT analysis, is predictive of LTOT initiation in COPD patients.  相似文献   
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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 探讨垂黄清脉冲剂对冠心病稳定型心绞痛(热毒痰瘀证)患者NF-κB信号通路的调控。方法 本试验研究方法采用单盲、随机、对照法,选取就诊于宁夏医科大学总医院临床诊断为冠心病稳定型心绞痛(热毒痰瘀证)患者94例,将其随机分入对照组48例和试验组46例。两组均给予内科常规西药治疗,对照组加服银丹心脑通软胶囊,试验组加服垂黄清脉冲剂,疗程为3个月。于治疗前、后记录患者的基本情况,并采集血清样本,用酶联免疫吸附测定法(Elisa法)检测血清中TNF-α、NF-κB、IL-6、ICAM-1、VCAM-1、ET-1、NO浓度水平进行对比,用SPSS22.0将数据进行统计学分析。结果 与治疗前比较,两组治疗后Gensini积分、血清中TNF-α、NF-κB、IL-6、ICAM-1、VCAM-1、ET-1浓度水平均较治疗前显著降低,NO浓度水平显著升高(P < 0.05,P < 0.01),其中试验组显著程度尤为明显(P < 0.01)。与治疗后对照组比较,试验组Gensini积分、血清中TNF-α、NF-κB、IL-6、ICAM-1、VCAM-1、ET-1浓度水平降低,NO浓度水平升高趋势更明显(P < 0.01)。结论 垂黄清脉冲剂治疗冠心病稳定型心绞痛(热毒痰瘀证)在改善患者症状;改善冠状动脉管腔狭窄程度;通过降低炎症标志物TNF-α、NF-κB、IL-6、ICAM-1、VCAM-1的水平,减小ET-1/NO比值,从而对NF-κB信号通路进行部分调控,以有效抑制或截断血管内皮的炎症级联反应过程,清除炎症损伤因素以及保护血管内皮功能等方面均有显著优势,临床疗效确切值得肯定和推广应用。  相似文献   
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BackgroundTo date, no previous studies have evaluated the relationship between sleep duration and quality of life (QOL) or depression in the general population after controlling for daytime sleepiness and sleep disturbances.MethodsA web-based cross-sectional survey was conducted with 8698 subjects aged 20–69 years. We examined the relationships between weekday sleep duration and daytime sleepiness, sleep disturbance, QOL and depression, using the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (without the item for sleep duration), 8-item Short Form and Center for Epidemiological Studies Depression Scale (CES-D).ResultsDaytime sleepiness tended to increase in proportion to shorter weekday sleep durations. Sleep disturbances, physical and mental QOL, and CES-D scores were worse in both the shorter and longer sleep groups compared with the group with 7–8 h of sleep. Hierarchical logistic regression analyses revealed that short sleep duration but not long sleep duration was significantly associated with reduction of both physical and mental QOL, even after controlling for the presence of daytime sleepiness and sleep disturbance. Both short and long sleep duration were independently and significantly correlated with depression after controlling for daytime sleepiness; however, there was no statistically significant association after adjusting for the effects of sleep disturbance.ConclusionsThe results suggested adverse effects of short sleep but not long sleep on both physical and mental QOL. In addition, the negative impact of specific types of sleep disturbance on depression may be greater than the impact of shortening of sleep duration.  相似文献   
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目的探讨研究一次性湿热交换器在新生儿机械通气长途转运中应用的临床意义。方法 2017年1月-2017年12月,我院120转运中心长途转运接收786例机械通气新生儿,786例患儿随机分为常规气道护理(对照组)和转运途中应用一次性湿热交换器组(治疗组),对比转运过程中的吸痰次数、肉眼可见痰痂形成率、堵管发生率、脱管发生率、人机对抗发生率。结果研究数据显示治疗组吸痰次数、肉眼可见痰痂形成率、堵管发生率、脱管发生率、人机对抗发生率有显著性差异(P<0.05)明显低于对照组。结论在机械通气新生儿长途转运中,一次性湿热交换器的可减少转运患儿吸痰次数发生率、降低肉眼可见痰痂形成率、堵管发生率、脱管发生率、人机对抗发生率具有明显优越性,值得推广。  相似文献   
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