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目的:运用功能性心肌血流指数(MBFI)评价缺血性冠心病(ICAD)可行性分析。方法:回顾性分析冠心病疑似患者行冠状动脉CT血管成像(CCTA)检查,同期接受有创冠状动脉造影(ICA)及导管法心肌血流储备分数(FFR)检查共81例患者,其中男性43例,女性38例,年龄(59.27±9.09)岁;计算MBFI;以FFR≤0.80为金标准,分别以四格表诊断试验确定MBFI与ICA的最佳切点值来判断ICAD;评价MBFI、ICA的ROC曲线特征及诊断准确度。结果:81例患者,CCTA扫描平均剂量为(3.06±1.22)mSv。MBFI、ICA最佳切点值分别为0.074、70%,25例患者FFR≤0.80。MBFI、ICA两者ROC曲线下面积分别为0.825、0.699(Z=2.024,P=0.0429),其敏感度、特异度、阳性预测值、阴性预测值分别为88.00%、80.35%、66.67%、93.75%和76.00%、51.79%、41.30%、82.86%,诊断准确度分别为82.72%、59.26%(χ2=10.753,P<0.01)。33例患者(40.74%,33/81)ICA狭窄程度为65%或70%,其中27例患者(81.82%,27/33)心肌不缺血,运用MBFI值大于0.074可明确23例患者心肌并不缺血(69.70%,23/33)。结论:MBFI属于功能性指标,可用于排查缺血性冠心病。  相似文献   
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Objectives

This study applied advanced 4-dimensional flow magnetic resonance imaging processing to assess differences in aortic flow dynamics after valve sparing root replacement, with and without reconstruction of the Valsalva sinuses.

Methods

We enrolled patients after valve sparing root replacement with a straight tubular prosthesis (n = 10) or with a prosthesis with Valsalva neosinuses (n = 10); age-matched subjects without cardiovascular diseases served as controls (n = 10). 4-Dimensional flow magnetic resonance imaging acquisitions were performed on a 3.0T magnetic resonance imaging unit. In-house processing was used to segment the aortic lumen and extract the volumetric 4-dimensional flow velocity field. Velocity flow streamlines were computed to compare the amount of rotational flow and wall shear stress. Occurrence of abnormal wall shear stress (WSS) was estimated within the descending aorta of each surgical group.

Results

Physiologic-like sinus vortices were visible in the aortic root when using the prosthesis with neosinuses, whereas straight tubular graft revealed localized intrados malrotations (P = .003 for organized vortical structures vs neosinuses graft and P < .001 vs control). In the ascending aorta, recreation of the sinuses resulted in significantly lower velocity and WSS than in the straight tubular graft (P < .001) and controls (P < .001), these alterations were attenuated in the mid-descending aorta. Incidence of abnormal WSS was markedly higher in the straight tube grafts than neosinus of Valsalva grafts.

Conclusions

Re-creation of the sinuses of Valsalva during valve-sparing root replacement is associated with more physiologic flow and significantly lower WSS in the aortic root. Lower WSSs in the distal thoracic aorta is a novel finding with potential implications on distal aortic remodeling.  相似文献   
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BackgroundComputerized tomography‐guided celiac plexus neurolysis has become almost a safe technique to alleviate abdominal malignancy pain. We compared the single needle technique with changing patients’ position and the double needle technique using posterior anterocrural approach.MethodsIn Double Needles Celiac Neurolysis Group (n = 17), we used two needles posterior anterocrural technique injecting 12.5 mL phenol 10% on each side in prone position. In Single Needle Celiac Neurolysis Group (n = 17), we used single needle posterior anterocrural approach. 25 mL of phenol 10% was injected from left side while patients were in left lateral position then turned to right side. The monitoring parameters were failure block rate and duration of patient positioning, technique time, Visual Analog Scale, complications (hypotension, diarrhea, vomiting, hemorrhage, neurological damage and infection) and rescue analgesia.ResultsThe failure block rate and duration of patient positioning significantly increased in double needles celiac neurolysis vs. single needle celiac neurolysis (30.8% vs. 0.13.8±1.2 vs. 8.9 ± 1; p = 0.046, p ≤ 0.001 respectively). Also, the technique time increased significantly in double needles celiac neurolysis than single needle celiac neurolysis (24.5 ± 5.1 vs. 15.4 ± 1.8; p ≤ 0.001). No significant differences existed as regards visual analogue scale: double needles celiac neurolysis = 2 (0‐5), 2 (0‐4), 3 (0‐6), 3 (2‐6) and single needle celiac neurolysis = 3 (0‐5), 2 (0‐5), 2 (0‐4), 4 (2‐6) after 1 day, 1 week, 1 and 3 months respectively. However, visual analogue scale in each group reduced significantly compared with basal values (p ≤ 0.001). There were no statistically significant differences as regards rescue analgesia and complications (p > 0.05).ConclusionSingle needle celiac neurolysis with changing patients’ position has less failure block rate, less procedure time, shorter duration of patient positioning than double needles celiac neurolysis in abdominal malignancy.  相似文献   
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Background

Vitiligo is an autoimmune disease with varying pathological features. Activation of the CCL20-CCR6 axis plays an important role in chronic inflammatory diseases. However, whether CCL20-CCR6 and Th1/17 cells are indicative of active vitiligo is unclear.

Objective

To investigate the potential role of CCL20 and the involvement of Th1/17 and Tc1/17 cells in the mechanism in vitiligo.

Methods

One hundred patients with vitiligo, and 20 healthy controls were included. The serum and blister fluid IL-17, IFN-γ, CCL20, and CXCL10 were studied using enzyme-linked immunosorbent assays. The numbers of Th1/17 cells and Tc1/17 cells in circulation were quantified using flow cytometry. CCR6 mRNA in peripheral blood mononuclear cells (PBMCs) was analyzed by real-time polymerase chain reaction and the protein level was confirmed by western blotting. CCR6 and CCL20 expression in lesions was analyzed by immunohistochemistry.

Results

The serum CCL20 level was significantly elevated in patients with vitiligo. The level of serum CCL20 was higher in active than in the stable stage, which correlated positively with the Vitiligo European Task Force spreading score and the Vitiligo Area Scoring Index score. Patients with active vitiligo had elevated numbers of circulating Th1/17 cells and Tc1/17 cells, and upregulated expression of CCR6 in PBMCs and lesions. After effective treatment, the level of CCL20 in sera and blister fluid was significantly decreased, as were the numbers of circulating Th1/17 cells and Tc1/17 cells.

Conclusion

CCL20 might be a vital biomarker of active vitiligo, and circulating Th1/17 and Tc1/17 cells are involved in the pathogenesis of vitiligo.  相似文献   
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抓取“微医网”医患评论数据,对其中时滞与患者满意度进行关联分析,并对评论内容进行主题挖掘,提取不同时滞区间内患者重点关注的内容。通过对患者评论文本不同时滞区间内容的分析,寻找满意度提升策略,以缓解医患关系。使用K-means将患者反馈数据根据就诊后时长反馈分为“短期”和“长期”,通过LDA主题提取模型,对满意度划分后的患者评论文本挖掘不同时滞区间内患者所关注的重点内容,将其差异进行对比分析发现,患者就诊满意度随着时滞呈现趋高现象,不同时滞文本显示患者评论维度大致相同,但随着时滞区间的转移,患者所关注的就诊体验内容也有所变化。  相似文献   
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