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71.
目的探讨下壁导联P-R段明显下斜与运动试验假阳性的关系。方法比较76例运动试验阳性经冠状动脉造影确诊为真阳性组57例、假阳性组19例的运动试验参数。结果假阳性组有较长的运动总时间(389±112s∶287±95s,P<0.01),达到较大的代谢当量(7.9±1.9mets∶6.6±1.5mets,P<0.01),ST段压低≥1mm时间延长(284±140s:192±97s,P<0.01),运动中较少诱发胸痛及至少2个下壁导联P-R段明显下斜的比例较高(74%∶20%,P<0.01),若以运动总时间≥300s、至少2个下壁导联P-R段明显下斜判断运动试验假阳性,其敏感性为63%,特异性为91%,预测价值为88%。结论运动总时间≥300s、至少2个下壁导联P-R段明显下斜对运动试验假阳性的判断有较高的特异性。 相似文献
72.
《JACC: Cardiovascular Imaging》2022,15(8):1427-1438
BackgroundIncreased inflammation and myocardial injury can be observed in the absence of myocardial infarction or obstructive coronary artery disease (CAD).ObjectivesThe authors determined whether biomarkers of inflammation and myocardial injury—interleukin (IL)-6 and high-sensitivity cardiac troponin (hs-cTn)—were associated with the presence and extent of CAD and were independent predictors of major adverse cardiovascular events (MACEs) in stable chest pain.MethodsUsing participants from the PROMISE trial, the authors measured hs-cTn I and IL-6 concentrations and analyzed computed tomography angiography (CTA) images in the core laboratory for CAD characteristics: significant stenosis (≥70%), high-risk plaque (HRP), Coronary Artery Disease Reporting and Data System (CAD-RADS) categories, segment involvement score (SIS), and coronary artery calcium (CAC) score. The primary endpoint was a composite MACE (death, myocardial infarction, or unstable angina).ResultsThe authors included 1,796 participants (age 60.2 ± 8.0 years; 47.5% men, median follow-up 25 months). In multivariable linear regression adjusted for atherosclerotic cardiovascular disease (ASCVD) risk, hs-cTn was associated with HRP, stenosis, CAD-RADS, and SIS. IL-6 was only associated with stenosis and CAD-RADS. hs-cTn above median (1.5 ng/L) was associated with MACEs in univariable analysis (HR: 2.1 [95% CI: 1.3-3.6]; P = 0.006), but not in multivariable analysis adjusted for ASCVD and CAD. IL-6 above median (1.8 ng/L) was associated with MACEs in multivariable analysis adjusted for ASCVD and HRP (HR: 1.9 [95% CI: 1.1-3.3]; P = 0.03), CAC (HR: 1.9 [95% CI: 1.0-3.4]; P = 0.04), and SIS (HR: 1.8 [95% CI: 1.0-3.2]; P = 0.04), but not for stenosis or CAD-RADS. In participants with nonobstructive CAD (stenosis 1%-69%), the presence of both hs-cTn and IL-6 above median was strongly associated with MACEs (HR: 2.5-2.7 after adjustment for CAD characteristics).ConclusionsConcentrations of hs-cTn and IL-6 were associated with CAD characteristics and MACEs, indicating that myocardial injury and inflammation may each contribute to pathways in CAD pathophysiology. This association was most pronounced among participants with nonobstructive CAD representing an opportunity to tailor treatment in this at-risk group. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550) 相似文献
73.
74.
先天缺牙是牙齿发育过程中常见的牙数目发育异常,对患者的颌面部发育及美观和咀嚼功能产生严重的影响。根据有无伴发全身症状,先天缺牙可分为综合征型先天缺牙与非综合征型先天缺牙。近几年发现新的相关基因和新的突变位点及分子机制已成为目前非综合征型先天缺牙基因研究的主要方向。本文通过对近年来文献的回顾,对与非综合征型先天缺牙主要相关的Wnt/β-catenin信号通路、TGF-β/BMP信号通路、PAX9基因和MSX1基因、EDA/EDAR/NF-κb信号通路的分子机制以及相互调节的紧密联系进行综述,为未来先天缺牙的防治提供了新的理论基础。非综合征型先天缺牙致病基因的分子机制的研究目前甚少,对于其机制的精准探索将成为先天缺牙未来主要的研究方向之一。 相似文献
75.
目的探讨斜外侧入路稚间融合术(OLIF)治疗腰椎融合术后邻近节段退变性疾病(ASD)的疗效。方法回顾性分析2017年6月至2019年12月18例行OLIF术治疗ASD患者的临床资料。记录手术时间、术中出血量、并发症、术后住院天数等。临床疗效评价采用视觉模拟量表(VAS)评分、日本骨科学会(JOA)评分和功能障碍指数(ODI)。摄腰椎正侧位X片,测量手术前后椎间隙高度(IDH)、椎间孔高度(IFH)和椎间孔面积(IFA)等影像学参数。摄腰椎CT三维重建评估植骨融合情况。结果平均手术时间(71±15)min(50~95 min),手术出血量(65±28)ml(20~200 ml),术后平均住院(7±2)d(4~9d)。随访时间12~36个月(平均18个月),术后末次随访的VAS评分、JOA评分和ODI指数比术前明显改善(P<0.05),影像学测量结果显示手术节段IDH、IFH、IFA由术前(5.5±0.6)mm、(15.3±1.4)mm、(135.3±6.5)mm分别增至术后(10.4±0.5)mm、(20.1±2.2)mm、(200.6±12.5)mm。术后2例患者出现术侧大腿前侧疼痛、屈髖无力,对症处理后症状消失。1例患者出现融合器下沉,但未出现临床症状,末次随访时椎间植骨已融合。所有患者术后1年植骨均获融合,未发现ASD复发。结论OLIP是治疗腰椎融合术后ASD的安全有效术式,获得满意的近期临床疗效。 相似文献
76.
目的:探索颈性眩晕的椎动脉寰枕段(V3段)血管形态病理学改变.方法:1999年6月至2011年11月,采用椎-基底动脉CT血管造影三维重建技术(3D-CTA)对1 680例颈性眩晕患者的血管形态影像进行回顾性分析,观察其椎动脉V3段血管形态病理学改变情况.其中男783例,女897例;年龄22~70岁,平均52.8岁,所有病例经多普勒检查显示椎基底动脉流速加快或减慢.结果:1 680例颈性眩晕患者在V1-V4段有3 360支血管被检测,血管异常支数有2 778支,其中V1段有829支,V2段有421支,V3段有328支,V4段有1 190支.颈性眩晕患者椎动脉V3段血管形态病理学有椎动脉血管痉挛(232支)、椎动脉血管缺如(37支)、椎动脉血管出孔异常(31支)、椎动脉血管局限性狭窄4种改变.结论:颈性眩晕的椎动脉V3段存在4种血管形态病理学改变,可以以3D-CTA检查结果来判断预后并采取适当的治疗方法. 相似文献
77.
Roy RS Karle IL Raghothama S Balaram P 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(47):16478-16482
Conformational studies on the synthetic 11-aa peptide t-butoxycarbonyl (Boc)-Val-Ala-Phe-alpha-aminoisobutyric acid (Aib)-(R)-beta3-homovaline (betaVal)-(S)-beta3-homophenylalanine (betaPhe)-Aib-Val-Ala-Phe-Aib-methyl ester (OMe) (peptide 1; betaVal and betaPhe are beta amino acids generated by homologation of the corresponding l-residues) establish that insertion of two consecutive beta residues into a polypeptide helix can be accomplished without significant structural distortion. Crystal-structure analysis reveals a continuous helical conformation encompassing the segment of residues 2-10 of peptide 1. At the site of insertion of the betabeta segment, helical hydrogen-bonded rings are expanded. A C15 hydrogen bond for the alphabetabeta segment and two C14 hydrogen bonds for the alphaalphabeta or betaalphaalpha segments have been characterized. The following conformational angles were determined from the crystal structure for the beta residues: betaVal-5 (= -126 degrees, = 76 degrees, and psi = -124) and betaPhe-6 (=-88 degrees, = 80 degrees, and psi =-118). The N terminus of the peptide is partially unfolded in crystals. The 500-MHz 1H-NMR studies establish a continuous helix over the entire length of the peptide in CDCl3 solution, as evidenced by diagnostic nuclear Overhauser effects. The presence of seven intramolecular hydrogen bonds is also established by using solvent dependence of NH chemical shifts. 相似文献
78.
N E Mezilis F I Parthenakis M K Kanakaraki M E Marketou H E Mavrakis P E Vardas 《European heart journal》2000,21(10):814-822
AIMS: The association between stress-induced ST elevation and functional recovery following revascularization after myocardial infarction remains unclear. We assessed the relative accuracy of dobutamine- and exercise-induced ST elevation in Q wave leads in predicting functional recovery following revascularization, and we investigated the relationship of ST elevation to different wall motion responses to dobutamine. METHODS AND RESULTS: Thirty-nine patients underwent dobutamine stress echo and exercise test 8+/-2 days after Q wave myocardial infarction. All patients underwent angiography and subsequent revascularization. Follow-up echocardiograms were obtained 7+/-4 weeks after revascularization. Functional recovery was assessed by the difference between the baseline and the follow-up asynergy index. Nineteen patients (48%) developed dobutamine- and exercise-induced ST elevation. There was significant agreement between the tests (k=0.58, P<0.001). We found a significant correlation between dobutamine and exercise-induced ST elevation with functional recovery following revascularization (r=0. 45, P<0.005 and r=0.7, P<0.001, respectively). The parameters with the highest predictive value for functional recovery were: (a) the biphasic response during dobutamine infusion, (b) the development of ST elevation in both tests, and (c) the development of exercise-induced ST elevation in more than three leads. CONCLUSION: There is a strong association between dobutamine- and exercise-induced ST elevation with functional recovery following revascularization. Exercise-induced ST elevation in more than three leads and a biphasic response during dobutamine infusion accurately predict functional recovery. 相似文献
79.
This overweight woman's case, who underwent a primary coronary intervention for STEMI, reminds us how much the trans-radial angioplasty is interesting in this particular case leaning on the recent literature, randomized trials and registries, in terms of major adverse events reduction including mortality. We are going to debate about hesitation of using radial approach whose only everyday's practising could make this approach a STEMI one. 相似文献
80.
aVR导联ST段抬高对急性心肌梗死预后的价值 总被引:6,自引:0,他引:6
目的探讨心电图aVR导联ST段抬高对急性前壁心肌梗死患者预后的价值。方法首次入院急性前壁心肌梗死患者57例,对其心电图和冠状动脉造影及临床资料进行对比分析。根据心电图aVR导联ST段变化分为抬高组、无偏移组。结果梗死相关血管为左主干病变的ST段抬高组、ST段无偏移组分别为5例(21.7%)、1例(2.9%),两组统计有显著性差异(p〈0.01);病变范围为多支病变ST段抬高组、ST段无偏移组分别为10例(43.4%)、8例(23.5%),两组统计有显著性差异(p〈0.05);发生心脏事件ST段抬高组、ST段无偏移组分别为8例(34.8%)、3例(8.8%),两组有显著性差异(p〈0.01)。结论aVR导联ST段抬高对预测急性前壁心肌梗死患者的预后有重要的价值,应高度重视。 相似文献