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61.
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   
62.
[目的]探讨粘附分子CD18、CD54粘附功能及其表达变化与急性脑梗塞(ACI)关系.[方法]用流式细胞术检测88例ACI患者白细胞粘附分子CD18、CD54含量与脑梗塞发生时程、部位、面积及治疗前后表达。并与30例正常人作对照.[结果]ACI患者CD18、CD54表达明显增高,与正常对照组比较差异显著(P<0.05),与梗塞面积、部位关系不大;ACI患者CD18、CD54表达在7d内均可有较高水平的表达,治疗10d后表达降低,治疗前后比较CD18、CD54差异有意义(P<0.05).[结论]CD18、CD54参与脑梗塞发生发展病理过程.可做为诊断脑梗塞、评估预后的一项辅助指标.  相似文献   
63.
[目的]研究脑梗塞患者血中一氧化氮(NO)的含量与血小板功能之间的关系.[方法]将20例脑梗塞患者分别于发病急性期和稳定期采用硝酸还原酶法测血中NO含量;用光电比浊法和免疫荧光分析法分别测定血小板聚集率(PAgT)和血小板α-颗粒膜蛋白(GMP-140)水平;同时检测正常对照15例[结果]血清中NO含量在发病急性期较正常对照明显增高(P<0.01).同时,PAgT与正常对照有显著性差异(PADP<0.05,PADR<0.01);而血小板GMP-140在急性期和稳定期较正常对照均有显著性差异(P<0.01).[结论]脑梗塞发病急性期随着血中NO含量的增高,导致PAgT受抑,血小板GMP-140水平减低.  相似文献   
64.
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   
65.
Objective: To establish a new assay for platelet-activating factor (PAF), to compare it with bio-assay; and to discuss its significance in some elderly people diseases such as cerebral infarction and coronary heart disease. Methods: To measure PAF levels in 100 controls, 23 elderly patients with cerebral infarction and 65 cases with coronary heart disease by reversed phase high-performance liquid chromatographic technique (rHPLC). Results: rHPLC is more convenient, sensitive, specific, and less confusing, compared with bio-assay. The level of plasma PAF in patients with cerebral infarction was higher than that in the controls (P<0.01), and in patients with coronary heart disease. Conclusion: Detection of PAF with rHPLC is more reliable and more accurate. The new assay has important significance in PAF research.  相似文献   
66.
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   
67.
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   
68.
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   
69.
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   
70.
本研究利用κ-阿片受体激动剂U50488H预处理(U50488H pretreatment,UP)大鼠,在离体Langendorff灌流心脏和缺血/复灌模型上观察κ-阿片受体激动剂诱发的延迟性心肌保护作用,研究结果表明U50488H预处理大鼠24h后,可明显改善心肌缺血后的复灌期内LVEDP的抬高,以及LVDP和±dP/dtmax的下降(P<0.05);其作用可被κ阿片受体选择性拮抗剂Nor-binaltorphimine(nor-BNI)所阻断.结论刺激κ-阿片受体诱导了延迟性心肌保护作用.  相似文献   
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