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21.

Background and objective

One of the important applications of non-invasive respiration monitoring using ECG signal is the detection of obstructive sleep apnea (OSA). ECG-derived respiratory (EDR) signals, contribute to useful information about apnea occurrence. In this paper, two EDR extraction methods are proposed, and their application in automatic OSA detection using single-lead ECG is investigated.

Methods

EDR signals are extracted based on new respiration-related features in ECG beats morphology, such as ECG variance (EDRVar) and phase space reconstruction area (EDRPSR). After evaluating the EDRs by comparing them to a reference respiratory signal, they are used in an automatic OSA detection application. Fantasia and Apnea-ECG database from PhysioNet are used for EDRs assessments and OSA detection, respectively. The final performance of our OSA detection is tested on an independent test data which is also compared with results of other techniques in the literature.

Results

The extracted EDRs, EDRVar and EDRPSR show correlations of 72% and 70% with reference respiration, which outperform the other state-of-the-art EDR methods. After feature extraction from EDRs and RR intervals series, the combination of RR and EDRPSR feature sets achieved 100% accuracy in subject-based apnea detection on independent test data, and also minute-based apnea detection is done with accuracy, sensitivity and specificity of 90.9%, 89.6% and 91.8%, which is better than other automatic algorithms in the literature.

Conclusions

Our OSA detection system using EDRs features yields better independent test results compared with other state-of-the-art automatic apnea detection methods. The results indicate that ECG-based OSA detection system can classify OSA events with high accuracy and suggest a promising, non-invasive and efficient method for apnea detection.  相似文献   
22.
目的:初步探讨AMPK在内质网应激所致COPD大鼠肺泡上皮细胞凋亡中所起的作用及机制。方法:实验分三组:对照组,COPD模型组,AICAR干预组,以香烟烟雾烟熏加气管内滴注脂多糖方法构建COPD大鼠模型,取大鼠肺组织行HE染色病理观察,免疫组化,western blot检测p-AMPK/AMPK,ORP150,caspase-3及CHOP表达,TUNEL法检测各组凋亡情况。结果:病理HE染色提示模型组大量炎症细胞浸润,肺大疱形成,支气管壁发生狭窄;AICAR干预组炎症细胞较模型组减少。与正常对照组相比,免疫组化及western blot均提示模型组中p-AMPK和ORP150蛋白表达含量增强,差异有统计学意义(P0.05)。而AICAR干预组中p-AMPK/AMPK及ORP150蛋白表达较模型组明显上升,差异有统计学意义(P0.05)。内质网应激相关凋亡指标CHOP及caspase-3的表达在模型组明显增强,较正常组比较差异有显著性(P0.05),而AICAR组中凋亡指标较模型组明显下调。结论:AMPK可以保护肺泡上皮细胞免于香烟烟雾所致内质网应激凋亡,且有可能通过增加ORP150来实现其保护作用。  相似文献   
23.
Phototherapy is commonly used in the treatment of hyperbilirubinemia in newborns. No serious side effects related to phototherapy have been observed, but concerns regarding its potential to damage DNA have been expressed, based on animal or cell-culture studies. The aim of this study was to investigate, in neonates with hyperbilirubinemia, the possible relation between phototherapy and DNA damage. The study included 33 full-term newborns with non-physiological jaundice and 14 healthy newborns with physiological jaundice as controls. Phototherapy was performed with an array of six fluorescent lamps producing radiation with wavelengths of 480–520 nm at 12 μW/cm2/nm. DNA damage in lymphocytes was determined by use of the alkaline comet assay. The DNA damage increased significantly with the duration of phototherapy, as shown by measurements at 24, 48, and 72 h (P < 0.001). These findings indicate that phototherapy, widely used in neonatology units, increases DNA damage in newborns. It remains to be seen whether the genotoxic effect observed in the present study can cause any long-term health effect in phototherapy-treated infants in later life.  相似文献   
24.
25.
The kidneys and liver are the major routes for organic anion elimination. We have recently shown that acute obstructive jaundice is associated with increased systemic and renal elimination of two organic anions, p-aminohippurate and furosemide, principally excreted through urine. This study examined probable adaptive mechanisms involved in renal elimination of bromosulfophthalein (BSP), a prototypical organic anion principally excreted in bile, in rats with acute obstructive jaundice. Male Wistar rats underwent bile duct ligation (BDL rats). Pair-fed sham-operated rats served as controls. BSP renal clearance was performed by conventional techniques. Renal organic anion-transporting polypeptide 1 (Oatp1) expression was evaluated by immunoblotting and IHC. Excreted, filtered, and secreted loads of BSP were all higher in BDL rats compared with Sham rats. The higher BSP filtered load resulted from the increase in plasma BSP concentration in BDL rats, because glomerular filtration rate showed no difference with the Sham group. The increase in the secreted load might be explained by the higher expression of Oatp1 observed in apical membranes from kidneys of BDL animals. This likely adaptation to hepatic injury, specifically in biliary components elimination, might explain, at least in part, the huge increase in BSP renal excretion observed in this experimental model. (J Histochem Cytochem 57:449–456, 2009)  相似文献   
26.
利用Sephadex LH-20,硅胶柱色谱和硅胶制备薄层色谱等分离方法反复分离纯化,从小花清风藤(Sabia parviflora Wall.ex Roxb)中分离得到9个化合物,通过波谱数据分析分别鉴定它们为二十五烷酸(1)、木栓酮(2)、5-氧阿朴菲碱(3)、3-氧化齐墩果酸甲酯(4)、齐墩果酸(5)、羽扇豆-20(29)-烯-3-酮(6)、羽扇豆醇(7)、β-谷甾醇(8)、脱镁叶绿甲酯酸(9)。化合物2,6、7、9首次从该植物中分离得到。  相似文献   
27.
目的通过对小细胞肺癌患者是否发生阻塞性肺炎的相关因素对比分析,了解伴有阻塞性肺炎小细胞肺癌患者临床特点。方法采用回顾性分析方法,收集2003年1月至2013年1月大连医科大学附属第二医院所收治的经组织学或细胞学确诊的小细胞肺癌患者共450例。经核查资料后,进入统计学的伴有阻塞性肺炎组100例,不伴有阻塞性肺炎组112例,均为初治。对以下因素进行分析:性别、年龄、居住环境、吸烟情况、分期、肿瘤位置、病理类型、初始疗效、NSE(神经元特异性烯醇化酶)。计数资料率和构成比的比较采用卡方检验。结果本组研究中伴有阻塞性肺炎组患者100例中,吸烟患者占76%,小细胞未分化癌患者占81%,中心型癌患者占52%,广泛期患者占57%,NSE阳性率为92%,均高于不伴有阻塞性肺炎组患者。不伴有阻塞性肺炎组的小细胞癌患者初始疗效有效率明显高于伴有阻塞性肺炎组患者。两组在性别、年龄、居住环境方面差异无统计学意义。结论伴有阻塞性肺炎组的小细胞肺癌患者NSE阳性率高于不伴有阻塞性肺炎组。吸烟是小细胞肺癌患者发生阻塞性肺炎的高危因素。阻塞性肺炎降低小细胞癌患者化疗初始疗效。  相似文献   
28.
目的:探讨儿童及成人阻塞型睡眠呼吸暂停低通气综合症(OSAHS)发病原因、睡眠呼吸紊乱严重程度及合并代谢异常程度的差别。方法:对我院2003年1月1日至20]0年7月1日71例诊断为OSAHS住院患者进行回顾性调查,登记年龄、性男日、发病原因、血压、白细胞计数、中性粒细胞比率、淋巴细胞比率、呼吸暂停低通气指数(AHI)、夜间最低血氧饱和度、微觉醒指数。根据年龄进行分组,年龄〈18岁者为A组,年龄≥18岁者为B组。比较两组发病原因、睡眠呼吸紊乱及合并代谢异常程度的差剐。结果:1.A组慢性扁桃体炎和(或)腺样体肥大发生率明显高于B组(P〈O.01),鼻中隔偏曲发生率明显低于B组(P〈0.01)。2.与B组比较,A组AHI及微觉醒指数降低,夜间最低血氧饱和度升高(P〈0.01);3.与B组比较,A组高血压、中性粒细胞比率、谷丙转氨酶比例降低(P〈0.05)。结论:A组睡眠呼吸紊乱程度及代谢异常较B组程度轻,更需关注成人阻塞型睡眠呼吸暂停低通气综合症的综合治疗。  相似文献   
29.
目的 观察宝乐安联合金酸萍颗粒对新生儿黄疸的临床疗效。方法 选择我院和酒泉市人民医院2016年10月至2018年9月间诊治的86例新生儿黄疸患儿为研究对象。入选患儿随机分成对照组与试验组各43例。其中对照组患儿给予金酸萍颗粒治疗,试验组患儿给予金酸萍颗粒联合宝乐安治疗。对两组患儿的临床治疗效果进行评价比较。结果 试验组与对照组患儿的临床治疗总有效率分别为95.3%和81.4%,差异有统计学意义(χ~2=9.385,P0.05)。试验组患儿胆红素恢复正常时间以及黄疸消失时间均显著短于对照组,差异有统计学意义(均P0.05)。结论 宝乐安与金酸萍颗粒联合用药对新生儿黄疸的临床疗效优于单用金酸萍颗粒,值得推广。  相似文献   
30.
Obstructive sleep apnea (OSA) affects a large percentage of the population and is increasingly recognized as a major global health problem. One surgical procedure for OSA is to implant polyethylene (PET) material into the soft palate, but its efficacy remains to be discussed. In this study, we provide input to this topic based on numerical simulations. Three 3 dimensional (3D) soft palate finite element models including mouth-close and mouth-open cases were created based on three patient-specific computed tomography (CT) images. A simplified material modeling approach with the Neo-Hookean material model was applied, and nonlinear geometry was accounted for. Young’s modulus for the implant material was obtained from uniaxial tests, and the PET implant pillars were inserted to the 3D soft palate model. With the finite element model, we designed different surgical schemes and investigated their efficacy with respect to avoiding the soft palate collapse. Several pillar schemes were tested, including different placement directions, different placement positions, different settings for the radius and the array parameters of the implant pillars, and different Young’s moduli for the pillars. Based on our simulation results, the longitudinal-direction implant surgery improved the stiffness of the soft palate to a small degree, and implanting in the transverse direction was evaluated to be a good choice for improving the existing surgical scheme. In addition, the Young’s modulus of the polyethylene material implants has an influence on the reinforcement efficacy of the soft palate.  相似文献   
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