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排序方式: 共有10000条查询结果,搜索用时 218 毫秒
61.
汽车驾驶员心电多相频谱分析 总被引:2,自引:0,他引:2
对117例汽车司机应用HBD-1心电多信息诊断仪进行心电多相频谱分析,其功率谱,传递相移,幅度直方图等五项指标总分阳性率明显高于对照组,随着驾车年限的增加,总分阳性率有升高趋势,心电频谱分析对230例冠心病病人阳性检出率84.78%。研究认为汽车司机是易发高血压,冠心病的危险人群,该方法在冠心病的环境流行病学研究中具有重要的临床,亚临床意义。 相似文献
62.
Anna Plachcinska Jacek Kusmierek Maciej Kosmider Malgorzata Bienkiewicz Julian Liniecki 《European journal of nuclear medicine and molecular imaging》1995,22(3):193-200
A quantified evaluation of planar cardiac perfusion scintigrams (the objective of the study), obtained using technetium-99m methoxyisobutylisonitrile (MIBI) was performed on the basis of an analysis of circumferential profile curves, representing the perfusion as seen in three typical projections. The analysis involved the curves obtained both at rest and after stress, and was based on a comparison of their shape (trend) with the normal trend (normative evaluation). The latter was obtained by means of an original method of iterative fitting of individual curves into the database. The base consisted of curves recorded in 53 patients (separately in males and females) with normal perfusion of the left ventricle (group I, the reference group). A group of 90 patients suspected of having coronary artery disease (group II) was subdivided into two subgroups on the basis of coronary arteriography: (a) those with and (b) those without critical stenosis of at least one artery. Profile curves characterising the LV perfusion were obtained at rest and after stress. Defects of perfusion were quantified by comparison of individual curves with the normal trends. By means of multivariate analysis it was demonstrated that vectors of mean values characterising the scintigraphically assessed defects of LV perfusion in the two subgroups of group II differed very significantly (P<10–5). Applying methods of discriminant analysis, a classification of patients from group II was performed into those with probable defects of perfusion and those free of such defects. The sensitivity, specificity and accuracy of diagnosis of coronary ischaemia, based on quantified planar99mTc-MIBI scintigraphy, reached 86%, 87% and 87%, respectively. 相似文献
63.
高频超声检测颈动脉内膜-中层厚度及外周血管内皮功能评价动脉粥样硬化 总被引:1,自引:0,他引:1
目的 探讨高频超声检测颈动脉内膜-中层厚度与肱动脉内皮依赖性舒张功能在动脉粥样硬化中的诊断价值.方法 冠状动脉造影的老年患者69例及青年志愿者20例,分别行颈动脉超声检查,同时采用充气加压法测定肱动脉血流介导的内径扩张值,超声测值与冠脉造影结果对照分析.结果 ①颈动脉内膜-中层厚度值随粥样硬化斑块的增多、冠脉狭窄程度的加重而增高;②动脉粥样硬化患者在内膜-中层厚度值增高之前即可出现内皮功能损伤,肱动脉内径扩张值降低早于内膜-中层厚度值增高之前出现,内径扩张值随冠脉狭窄程度加重而下降.结论 高频超声检测颈动脉内膜-中层厚度、内径扩张值诊断早期动脉粥样硬化敏感性高,并且有助于对冠脉狭窄程度作出判断. 相似文献
64.
目的 评价直接置入药物洗脱支架 (CYPHERTM,codis)在A或B1 型病变的冠心病患者治疗中的安全性、可行性。方法 6 2例接受CYPHERTM 支架直接置入的患者 (直接支架组 )和一般情况匹配的 5 1例球囊扩张后行冠脉支架术的患者 (常规支架组 ) ,比较两组的一般情况 ,冠脉造影及介入治疗即刻和临床随访结果。结果 直接支架组介入操作时间明显短于常规支架组 [(17.2± 8.6 )比 (2 6 .3± 7.1)min ,P <0 .0 1],直接支架组平均扩张压明显高于常规支架组 [(14± 3)比 (12± 1.9)atm ,P<0 .0 1],两组无一例发生介入治疗相关的严重心脏事件。随访期间两组严重心脏不良事件发生率无显著差异。结论 A或B1 型病变的冠心病患者CYPHERTM 支架直接置入术可缩短介入操作时间 ,即刻效果、并发症及中期临床随访与常规支架组差异无显著性意义 相似文献
65.
目的探讨经体外反搏治疗的冠心病患者血清对血管内皮细胞基因表达的调控效应。方法分别取接受体外反搏治疗的冠心病患者1、24和36h时间点的血清,用于培养人脐静脉血管内皮细胞。用cDNA基因芯片检测3个治疗时点反搏前、后血管内皮细胞基因表达谱。结果反搏前后比较,有10个基因(核转录因子、真核转录启动因子-4、平滑肌的肌球蛋白重链、α2-肌动蛋白、微管蛋白β肽链、组织相容蛋白G、黑色素黏附分子、神经介素B受体、蛋白激酶4K2、血小板凝血酶敏感蛋白-1)的表达在3个治疗时点上出现显著改变。在1h点均为上调,在24h、36h时点均为下调。结论体外反搏治疗冠心病患者血清对血管内皮细胞的炎症反应、细胞凋亡相关基因表达有调效应,并随体外反搏治疗时间的增加早抑制其表达的趋势。 相似文献
66.
Prevalence of silent myocardial ischemia in asymptomatic individuals with subclinical atherosclerosis detected by electron beam tomography 总被引:3,自引:0,他引:3
Anand D. Vijay Lim Eric Raval Usha Lipkin David Lahiri Avijit 《Journal of nuclear cardiology》2004,11(4):450-457
BACKGROUND: Electron beam tomography coronary calcium imaging is an evolving technique for the early detection of coronary atherosclerosis, and recent studies have established its prognostic value in asymptomatic individuals. The relationship of coronary artery calcium scores (CAC) to obstructive coronary artery disease (CAD) has been poorly studied but is clinically relevant because it determines which individuals are likely to benefit from revascularization procedures. Hence, we prospectively evaluated the prevalence of myocardial ischemia in asymptomatic patients with cardiovascular risk factors and subclinical atherosclerosis. METHODS AND RESULTS: We studied 864 asymptomatic patients with no previous CAD but with cardiovascular risk factors, referred for electron beam tomography coronary calcium imaging to our institution over an 18-month period. From this group, 220 consecutive patients (85% men; mean age, 61 +/- 9 years; age range, 31-84 years) with moderate to severe atherosclerotic disease (coronary calcium score > or =100 Agatston units) were prospectively evaluated by technetium 99m sestamibi single photon emission computed tomography (SPECT). Patients were followed up (mean follow-up, 14 months) and data regarding their subsequent clinical management recorded. Of the 220 patients, 119 had moderate atherosclerosis (CAC score of 100-400 Agatston units) and 101 had severe atherosclerosis (CAC score > or =400 Agatston units). Abnormal SPECT findings were seen in 18% of patients with moderate atherosclerosis (n = 21) and 45% of patients with severe atherosclerosis (n = 45). Increasing severity of atherosclerosis was related to increasing ischemic burden (summed difference score = 1 +/- 0.2 for CAC score of 100-400 Agatston units and 3.2 +/- 0.5 for CAC score > or =400 Agatston units). In a multivariate linear regression model incorporating risk factors, CAC was the only predictor of silent ischemia. CONCLUSION: In comparison to previously published data, we detected a higher prevalence of silent ischemia even in patients with moderate coronary atherosclerosis (18%). This may reflect the differing risk factor profile of our patient population. When coronary calcium screening is used to preselect asymptomatic patients with cardiovascular risk factors for myocardial perfusion imaging, the optimum coronary calcium score threshold will depend on the population prevalence of risk factors and asymptomatic obstructive CAD. 相似文献
67.
高压氧对冠心病患者C-反应蛋白的影响 总被引:4,自引:4,他引:0
目的 了解高压氧(HBO)治疗对冠心病患者C 反应蛋白 (CRP)的影响。方法 冠心病患者共 60例,随机分为HBO治疗组(HBO组)30例和对照组 30例。HBO治疗压力 0. 2MPa,每日 1次,每周 6次,共治疗 4周。比较治疗前后两组CRP的测定结果。结果 HBO组治疗后CRP与治疗前差异有显著性意义(P<0. 001);治疗后两组CRP差异有显著性意义(P<0. 001);治疗前两组CRP差异无显著性意义(P>0. 05);对照组治疗前后CRP差异无显著性意义 (P>0. 05)。结论 HBO治疗可显著降低冠心病患者的CRP含量。 相似文献
68.
目的:应用高频超声观察冠心病(CAD)患者,经阿托伐他汀治疗后对肱动脉内皮依赖性舒张功能(EDD)的改善作用。方法:经冠脉造影(CAG)确诊为CAD患者59例,利用高频超声血管技术检测阿托伐他汀对CAD患者治疗前后肱动脉EDD的疗效。结果:阿托伐他汀治疗2年后,EDD比治疗前有明显改善(P〈0.05),与对照组相比无显著性差异(P〉0.05)。常规治疗组治疗2年后,EDD无明显改善(P〉0.05),与阿托伐他汀组治疗后及对照组相比差异有显著性(P〈0.05)。结论:阿托伐他汀具有改善EDD的作用。 相似文献
69.
Using data from the National Health and Nutrition Examination Survey (NHANES II) 1976-1980, we demonstrate how cross-sectional total serum cholesterol surveillance data can be used by an individual to assess current and future personal cholesterol risk status. We propose statistical models, based on a person's current measured cholesterol level and the relationship between cross-sectional age and cholesterol percentile estimates, that will allow prediction of future cholesterol levels or the age at which specified cholesterol risk levels will be reached if no cholesterol-altering intervention is taken. These models incorporate the observed variation in the NHANES II data and expected intraperson biological variation and intralaboratory analytical variation. We illustrate the adequacy of the models using data from the longitudinal Framingham Study. 相似文献
70.
Peter Knesewitsch Sigrid Fritsch Eduard Kleinhans Udalrich Büll 《European journal of nuclear medicine and molecular imaging》1987,12(12):598-601
Results of 203 patients who underwent first pass radionuclide angiography (FP) and quantitative equilibrium radionuclide ventriculography (qERNV) were stored in a data base system and evaluated statistically. Eighty eight of these patients also underwent exercise equilibrium radionuclide ventriculography (E-qERNV). In patients with coronary artery disease (CAD) without previous myocardial infarction (MI), evaluation of global and regional ejection fraction (gEF, rEF) at rest revealed a poor sensitivity of 64%, the specificity was about 71% (qERNV). FP at rest revealed similar values of sensitivity (69%) and specificity (83%). Additional assessment of stress induced changes of gEF, significantly (P<0.05) improved sensitivity of qERNV in CAD patients without a history of previous MI to 84% (specificity 86%). In patients with one previous MI, however, similar values of sensitivity were found (RFP: 87%, R-qERNV: 84%, E-qERNV: 93%). In patients with several MI's, sensitivity was above 90% at rest and during exercise (R-FP: 96%, R-qERNV: 93%, E-qERNV: 100%). 相似文献