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41.
目的:研究不同体力活动水平女性教师递增负荷前后血清心肌酶的差异,进而评估不同体力活动水平女性教师运动中可能出现的心脏风险。方法:对受试者进行体力活动问卷调查,从中筛选87名健康女性教师进行递增负荷试验,测试运动测试前后的心肌酶指标进行比较分析。结果:1)运动前安静状态下,体力活动不足组心肌酶各指标值均低于中、高水平体力活动组,其中体力活动不足组CK-MB显著的低于中等组(P0.05)并且非常显著的低于高等组(P0.01)。2)运动测试后,体力活动高水平组CK值显著的高于体力活动不足组(P0.05),除AST以外,其余心肌酶水平随着体力活动水平的升高而升高。其中体力活动不足组AST值超过正常值范围,提示心肌组织出现了一定的损伤。3)除中等和高水平体力活动组的CK-MB运动后比运动前有所下降外,其余各组指标运动后都有所升高,特别是三组的CK、AST都非常显著的升高(P0.01),从运动前后差值比较分析来看,不足组的CK、AST增加值显著的高于中等组和高等组(P0.05)。结论:1.体力活动不足的高校女性教师安静状态下的心肌酶水平较低。2.递增负荷运动会引起高校女性教师心肌细胞出现一定程度的损伤,运动后血清心肌酶水平有所升高,而且体力活动不足女性的损伤更为严重,主要表现在心肌酶指标中的CK和AST。  相似文献   
42.
通过阐释心肌桥的形态结构和运动员心脏的特点,分析了心肌桥可能引起急性冠脉综合症、严重的心律失常甚至猝死。尤其是在运动情况下,心肌缺氧缺血等情况会较为明显。而心律失常在长期从事严格运动训练的运动员中时有发生。研究认为,在运动员选材中应将心肌桥的检查作为一项重要指标,对运动员选材的成功率有一定的帮助。  相似文献   
43.

Background

Early diagnosis is crucial for management of patients with suspected acute myocardial infarction (AMI). Among innovative and promising biomarkers, the recent interest raised on glycogen phosphorylase isoenzyme BB (GPBB) has prompted us to perform a meta-analysis of published studies.

Materials and methods:

A systematic electronic search was carried out on PubMed, Web of Science and Google Scholar, with no date restriction, to retrieve all articles that have investigated the early diagnostic performance of GPBB in patients with suspected AMI, and directly reported or allowed calculation of sensitivity and specificity. A meta-analysis of the reported sensitivity and specificity of each study and pooled area under the curve (AUC) was then performed by random effect approach. Heterogeneity was assessed by I-square statistics.

Results:

Eight studies were finally selected for analysis (941 subjects; 506 cases and 435 controls), with a high heterogeneity (I-squared, 86.3%). The resulting pooled estimates and 95% confidence interval were 0.854 (0.801–0.891) for sensitivity, 0.767 (0.713–0.815) for specificity, 0.826 (0.774–0.870) for negative predictive value, 0.802 (0.754–0.844) for positive predictive value, and 0.754 (0.602–0.907) for AUC. In those studies that have simultaneously assessed GPBB and a troponin immunoassay, the combination of these biomarkers did not significantly improve the performance of troponin alone.

Conclusion:

GPBB does not meet the current requirements for an efficient diagnosis of AMI when used as a stand-alone test, whereas its combination with troponin merits further investigation in larger trials.  相似文献   
44.
目的:测试服用和未服用β-受体阻断剂的心梗后患者(PMIP)在跑台运动中其功能、生理、临床及自我感觉方面的反应。方法:46名服用β-受体阻断剂的男性PMIP和55名未服用β-受体阻断剂的男性PMIP进行递增负荷运动实验,其间记录每级负荷时的摄氧量(VO2)、心率(HR)、血压和自我用力感觉(RPE),并持续监测12导联心电图(ECG)。结果:服用β-受体阻断荆的患者其安静时和运动中的HR、最大心率百分比(%HRmax)及心率血压乘积(RPP)显著低于未服用β-受体阻断剂的患者(P〈0.01)。运动中,服用β-受体阻断剂的患者有59%能够完成改良布鲁斯跑台方案的第Ⅳ级运动,而在未服用β-受体阻断剂的患者中仅有49%能完成这一负荷。两组在运动中各级别VO2、RPE及ST段下移无显著性差异。结论:由β受体阻断剂所致的HR降低并没有直接地影响到氧利用和代谢机能。  相似文献   
45.
目的:探讨间歇低氧训练对大鼠心肌毛细血管的影响,为高原训练方案的制定提供理论依据。方法:采用透射电镜技术观察大鼠心肌细胞毛细血管超微结构在低氧适应过程中的变化。结果:运动训练可以改善大鼠心肌细胞毛细血管超微结构;急性低氧可造成心肌超微结构的损伤;经过4wk的慢性间歇低氧运动训练后再进行急性低氧应激,心肌的损伤减轻。结论:急性运动后进入急性低氧应激,导致心肌损伤加重,是由于运动缺氧损伤和低氧损伤双重作用的结果,而4wk的慢性间歇低氧训练可减轻低氧环境对心肌的损伤。  相似文献   
46.
Objective: In addition to pH regulation, Na+/H+ exchange (NHE) has been shown to facilitate cell growth and proliferation. However, the effects of long-term inhibition of Na+/H+ exchange on cardiac structural and functional remodeling post myocardial infarction (MI) are still controversial. The present study was therefore carried out to further investigate the effects of long-term treatment with cariporide, a specific inhibitor of NHE-1, on cardiac remodeling after MI in rats; Methods: Male Wistar rats that underwent coronary ligation were randomly selected for cariporide treatment starting 6 h after induction of MI or no treatment. Treatment was continued up to 6 weeks post MI, after which, the arterial, venous and left ventricular catheters were chronically implanted. Twenty-four h later, after hemodynamic signals were recorded in conscious rats, they were sacrificed and hearts were taken out for morphological examinations; Results: Cariporide treatment decreased the heart weight and heart weight to body weight ratio (bothP<0.05), decreased left ventricular end-diastolic pressure (P<0.001), improved myocardial contractility (dP/dt max) (P<0.05) and tended to increase the survival of treated rats compared to that of untreated infarct rats; Conclusion: The results of the present study indicate that the long-term inhibition of NHE with cariporide can attenuate cardiac structural remodeling and improve left ventricular dysfunction in infarcted rats, and suggest that Na+/H+ exchange inhibition could be an effective therapeutic strategy for myocardial infarction-induced heart failure.  相似文献   
47.
目的:观察黄芪注射液配伍川芎嗪对家兔心肌缺血再灌注损伤的保护作用。方法:采用在体家兔冠状动脉阻断的缺血/复灌损伤模型,测定心肌梗死面积、血浆中乳酸脱氢酶(LDH)和肌酸激酶(CK)活性及各项心室力学指标。结果:与单纯缺血/复灌组相比,川芎嗪与黄芪两药明显降低心脏缺血/复灌后的梗死面积和血浆中LDH、CK含量,促进左室收缩压(LVSP)、最大左室收缩速率( dP/dtmax)和最大左室舒张速率(-dP/dtmax)的恢复,两药合用与单用比较各项指标的恢复更加显著。结论:黄芪与川芎嗪两药合用在保护心肌缺血再灌注损伤中有显著的协同作用。  相似文献   
48.
Myocardial infarction is a major consequence of coronary artery disease. Apart from the traditional risk factors of myocardial infarction, recently many reports have suggested that hyperhomocysteinemia plays important role in myocardial infarction. Plasma homocysteine level was determined in 60 myocardial infarction patients and in 35 age matched healthy individuals. Statistically significant differences (p<0.01) were observed in the mean of plasma homocysteine concentrations between the acute myocardial infarction patients (24.59±6.14 mM/L) and in normal healthy individuals (13.73 ±3.54 mM/L). The level of homocysteine in myocardial infarction patients is significantly high (p <0.01) among myocardial infarction patients when compared to that of the controls. The the present study indicates a strong association between plasma homocysteine and acute myocardial infarction among Tamilians, thus implying plasma homocysteine as a possible risk factor for myocardial infarction.  相似文献   
49.
Objective:To investigate the relationship between renal function and clinical outcomes among patients with acute ST-segment elevation myocardial infarction (ASTEMI), who were treated with emergency percutaneous coronary intervention (PCI). Methods: 420 patients hospitalized in Peking University First Hospital, diagnosed with ASTEMI treated with emergency (PCI) from January 2001 to June 2011 were enrolled in this study. Estimated glomerular filtration rate (eGFR) was used as a measure of renal function. We compared the clinical parameters and outcomes between ASTEMI patients combined renal insufficiency and the patients with normal renal function. Results:There was a significant increase in the concentrations of fibrinogen and D-Dimer (P<0.05) and a much higher morbidity of diabetes mellitus in the group of patients with chronic kidney disease (CKD; eGFR<60 ml/(min·1.73 m2)) (P<0.01). CKD (eGFR<60 ml/(min·1.73 m2)) was an independent predictor of in-hospital mortality for patients hospitalized with ASTEMI receiving PCI therapy rapidly (P=0.032, odds ratio (OR) 4.159, 95% confidence interval (CI) 1.127-15.346). Conclusions:Renal insufficiency is an independent predictor of in-hospital mortality for patients hospitalized with ASTEMI treated with primary PCI.  相似文献   
50.
目的探讨老年慢性肺心病伴发急性心肌梗死(AMI)的临床特点.方法对66例老年慢性肺心病伴发AMI的病人(A组)进行分析,并与老年单纯冠心病AMI152例(B组)作比较.结果A组疼痛发生率(45.4%)显著低于B组(83.9%)(p<0.01),A组急性左心衰、心源性休克发生率显著高于B组,分别为53.1%与25.0%,48.4%与21.7%(p<0.05),A组病死率(42.4%)显著高于B组(15.7%),肺心病对其伴发AMI的发生部位无影响.结论对老年肺心病患者突然发生的急性左心衰和/或心源性休克应高度警惕伴发AMI的可能.  相似文献   
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