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61.
背景 感染性休克患者存在肾脏血液灌注异常,严重时可诱发急性肾损伤(AKI),严重威胁患者生命安全;彩色多普勒超声(CDU)可用于评估肾脏血流变化,但有关其在感染性休克患者AKI评估中价值的研究较少。目的 通过CDU评价感染性休克患者AKI的发生情况及其血流动力学改变。方法 选取2019年6月至2021年7月徐州市中心医院收治的105例确诊为感染性休克的患者并纳入感染组,选取同期健康体检者58例并纳入对照组,收集受试者一般资料。采用CDU检查受试者肾脏血流动力学指标[肾动脉管腔内径(D)、收缩期血流峰值速度(Vs)、舒张末期血流速度(Vd)、阻力指数(RI)、搏动指数(PI)],比较感染组与对照组的一般资料及肾脏血流动力学指标。根据感染组患者入院72 h内发生AKI与否将其分为AKI组及非AKI组,比较AKI组与非AKI组肾脏血流动力学指标。应用受试者工作特征(ROC)曲线分析肾脏血流动力学指标对感染性休克患者发生AKI的预测价值。应用单因素分析及多因素Logistic回归分析探讨感染性休克患者发生AKI的影响因素。以AKI由轻到重的程度将患者分为AKIⅠ组、AKIⅡ组、AKIⅢ组,比较... 相似文献
62.
背景 冠心病属中医“胸痹心痛”范畴,其证候分布以血瘀证最为多见,与老年人相比,中青年血瘀证的发生率更高。本研究在团队前期研究基础上进行拓展,首次运用动脉弹性和血管内皮功能检测联合载脂蛋白比值诊断中青年冠心病血瘀证,旨在为早期发现中青年冠心病血瘀证提供新思路,也可为优化补充冠心病血瘀证的诊断标准提供参考。目的 探讨踝肱指数(ABI)、肱踝动脉脉搏波速度(baPWV)、血管舒张功能(FMD)联合载脂蛋白B与载脂蛋白A-1比值(apoB/apoA-1)与中青年冠心病血瘀证的关系及其预测价值。方法 选取2016年12月至2021年12月于中日友好医院中西医结合心脏内科住院治疗的中青年(<50岁)冠心病患者,并根据《冠心病血瘀证诊断标准》分为血瘀证组和非血瘀证组。收集患者首次冠状动脉造影前的ABI、baPWV、FMD和apoB/apoA-1等临床资料。采用多因素Logistic回归分析构建中青年冠心病患者血瘀证的预测模型,并采用受试者工作特征(ROC)曲线进行预测价值评价。结果 本研究共纳入中青年冠心病患者206例,其中血瘀证组127例,非血瘀证组79例。多因素Logistic回归分析结果... 相似文献
63.
目的 探讨分析基于心脏磁共振特征追踪技术(FT-CMR)的心脏功能评估参数对心房颤动冷冻球囊消融患者治疗后复发的预测效能。方法 选取2019年6月至2020年12月收治的126例预行冷冻球囊消融术的心房颤动患者为研究对象,术前均进行心脏磁共振检查,根据术后6个月内患者有无复发将其分为窦性心律组72例和房颤复发组54例。比较两组患者左心房应变及应变率参数,采用FT-CMR评估患者心脏功能,并进行单因素、多因素logistic回归分析,探讨FT-CMR心脏功能评估参数对心房颤动冷冻球囊消融术后复发的预测价值。结果 房颤复发组患者女性、高血压、糖尿病、非阵发性心房颤动比例显著高于窦性心律组(P<0.05)。房颤复发组患者左心房总应变(Es)、左心房正向应变率峰值(SRs)、左心房被动应变(Ee)、心室舒张早期负向应变率峰值(SRe)、左心房整体纵向应变(PLAS)参数值低于窦性心律组(P<0.05)。Logistic多因素回归分析结果显示,性别(OR=3.511,95%CI:1.036~11.906)、PLAS(OR=1.089,95%CI:1.039~1.141)是心房颤动冷冻... 相似文献
64.
1519例胎儿心电图的临床价值和相关因素分析 总被引:1,自引:0,他引:1
目的对1519例胎儿全部实行常规胎儿心电图(FECG)监测工作,探讨胎儿心电图应用情况,并对异常FECG结合临床,进行临床原因分析.方法采用随机湘样方法,应用杭州产FECG-D型胎儿心电图分析仪进行监测.结果发现采用横导联方式进行监测检出率为53.5%:在孕22w进行监测检出率为45.8%;异常FECG检出率为7.64%.结论对1519例FECG的监测发现采用横导联方式并在孕22w~26w期间进行监测检出率最高、波形效果好.并对监测发现的导致FECG异常改变的临床原因与胎儿宫内窘迫的关系进行浅要分析. 相似文献
65.
研究了长序列心电信号的最佳复杂度。先将原始序列符号化 ,再采用 L empel- Ziv算法来计算复杂度 ,探讨影响复杂度的各种因素 ,然后对三组不同信号即正常心电、心绞痛和心肌梗塞信号进行分析。结果表明 ,采用最佳阈值比用平均值为阈值得到的复杂度更能明显地分辨出正常和异常信号 ,原始序列符号化的阈值以及信号长度直接影响序列复杂度 ,因此 ,在实际信号的复杂度测量上 ,应采用最佳阈值和最佳信号长度。 相似文献
66.
癫痫的睡眠动态脑电图临床应用价值 总被引:2,自引:0,他引:2
孔峰 《现代电生理学杂志》2004,11(4):206-207,214
目的:探讨睡眠期动态脑电图(AEEG)在癫痫诊断中的作用。方法:利用 AEEG对836例癫痫患者自然睡眠期脑电波变化进行监测、分析。结果:正常106例 (12.7%),非特异性异常61例(7.3%),痫样波发放669例(80.0%),总异常730例 (87.3%)。痫样波出现于清醒期84例(12.5%),睡眠期408例(61.0%)。睡眠期明显高 于清醒期P<0.01。而睡眠期(NREM Ⅰ-Ⅱ期)占多数473/585例(80.7%)。结论:癫 痫和睡眠密切相关,通过自然和药物诱发睡眠,有助于提高癫痫脑电图阳性率,尤其是自然 睡眠AEEG对癫痫的定位诊断和分类更具有重要意义。对临床诊断困难的非典型发作及各种 不常见类型癫痫的作用更加突出,甚至起着决定性的作用。 相似文献
67.
Metabolic pathways leading to lipid biosynthesis in four different developmental stages of Schistosoma mansoni were explored and quantified by incubation in the presence of labeled precursors in a chemically defined medium. At the schistosomulum stage and in male, female, or paired worms, glycerol and oleate incorporation into neutral lipids, mainly in the form of triacylglycerols, was greater than into phospholipids, whereas in 11-and 15-day-old worms, synthesis mainly led to phospholipids. Incorporation into phospholipids was recovered largely in phosphatidylcholine, and distribution into other phospholipids depended on the developmental stage. Incorporation of choline and ethanolamine into their respective phospholipids represented up to 15% of the parasitic phospholipid content. The formation of phosphatidylcholine by phosphatidylethanolamine methylation occurred mainly in the immature parasitic stages. Inositol incorporation was also measurable, whereas [14C]serine incorporation was low or undetectable. Addition of 1-palmitoyl-2-[14C]oleyl phosphatidylcholine revealed a very high uptake of this phospholipid by the immature stages but further metabolism was not detectable. In contrast, adult S. mansoni were completely unable to take up or absorb this exogenous phospholipid. The most striking aspect of this study was the relatively high metabolic activity in 11-day-old worms and the lower but sustained activity on day 15 and at the schistosomulum stage. By comparison, biosynthetic activity in adult S. mansoni, on which research studies have been focused until now, was very low. We also discuss the participation of lipid metabolism in the constant renewal of the membrane complex which is essential to parasitism by S. mansoni. 相似文献
68.
Jan Schmeller Michael Wessolly Elena Mairinger Sabrina Borchert Thomas Hager Thomas Mairinger Kurt Werner Schmid Jeremias Wohlschlaeger Robert F.H. Walter Fabian D. Mairinger 《Pathology, research and practice》2019,215(2):381-386
Introduction
The usage of formalin-fixed paraffin embedded (FFPE) tissue is characterized by its long shelf-life and simple handling. Therefore it is the most commonly available tissue specimen in routine diagnostics and histological studies. Formaldehyde fixation may result in RNA degradation and cross linking with proteins, while storage conditions also affect RNA integrity. The present study was designed to investigate the influence of these factors on RNA analysis.Design
FFPE-derived RNA from sections of 23 patients with spontaneous pneumothoraxes was used. Unstained sections of FFPE tissue were stored at various temperatures (?80?°C, ?20?°C, 4?°C, 24?°C) prior to RNA extraction. The potential impact on RNA quality of semi-automatic and manual RNA isolation and three different deparaffinization agents (mineral oil, xylene and d-limonene) were compared.Results
The storage temperature of FFPE sections affects RNA concentration and fragmentation, with the optimal storage temperature below -20?°C. The RNA extracted with d-limonene shows equivalent quality to the RNA extracted using more toxic standard agents. The manual isolation provides a higher RNA yield compared to the semi-automatic isolation. However, no differences in the amount of longer RNA fragments were observed. Furthermore, the semi-automatic isolation showed an enhanced RNA quality.Conclusion
FFPE sections not directly used for RNA extraction should be stored below -20?°C to increase quality and yield of the RNA. Usage of semi-automatic isolation produces superior results and simplifies routine processes by having less hands-on-time. Replacement of toxic xylene by d-limonene may contribute to improved occupational safety while not influencing analytical results. 相似文献69.
The Thy-1 antigens or rat brain and thymus have been isolated and chemically characterized, but those of mice have not been identified. Moreover, it is uncertain whether the antigens are glycolipids or glycoproteins. This study with highly purified preparations of gangliosides GM1, 1GD1a, GD1b and GT1b from bovine brain and several ganglioside fractions from mouse brain showed that Thy-1 activity does not reside in gangliosides, but rather in the chloroform-methanol-insoluble residue of brain remaining after extraction of gangliosides. The antigen could be solubilized from this residue with a non-ionic detergent. The antigenic activity of the solubilized preparation was heat-labile but resistant to periodate. The chemical properties of the Thy-1 antigen of mouse brain are discussed. 相似文献
70.
Predictive value of early HCV RNA quantitation for sustained response in nonresponders receiving daily interferon and ribavirin therapy 总被引:2,自引:0,他引:2
Trimoulet P de Lédinghen V Foucher J Castéra L Fleury H Couzigou P 《Journal of medical virology》2004,72(1):46-51
The prognostic value of early hepatitis C virus (HCV)-RNA load was evaluated among nonresponder patients to previous interferon (IFN) therapy treated with daily IFN and ribavirin. One hundred-six nonresponders (83 men), mean age 44.8 +/- 11 years, were treated with IFN-alpha 2b 3 MU/day for 24 weeks, followed by 3 MU x 3/week for 24 weeks plus ribavirin 1-1.2 g/day for 48 weeks. HCV RNA was quantified by Versant HCV RNA 3.0 assay (Bayer). The predictive values of the baseline and the change in viral load at week 1, 4, and 12 for sustained virological responses were analyzed using receiver operating characteristic (ROC) curves, as well as predictive values of >2 log(10) drop from baseline by weeks 1, 4, and 12 in combination with undetectable HCV RNA for sustained virological response. Thirty-two patients (30.2%) were sustained virological responders. The highest area under the curve was obtained at week 4. The unquantifiable HCV RNA level, in combination with at least a 2 log(10) drop in viral load by week 4 and week 12, had a negative predictive value of 96% and 97%, respectively. Nonresponse can be predicted as early as week 4 or week 12 in nonresponders treated with daily IFN and ribavirin. 相似文献