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1.
作为心肌损伤的特异性指标,心肌肌钙蛋白(cTn)在临床诊断心肌病中具有较高的价值。马拉松等耐力运动后,血清cTn异常升高的生理、病理意义仍存在较大争议。通过总结马拉松等耐力运动后cTn的释放规律和右心室(RV)损伤情况,研究探讨了运动后血清cTn的可能来源,以及利用血清cTn评价运动后RV心肌损伤性质的可行性。研究认为:1)一次性马拉松等耐力运动后的血清cTn异常升高,可能是由于RV心肌结构蛋白损伤所致;2)一次性马拉松等耐力运动,可能导致不同性质的RV心肌损伤,通过结合运动后血清cTn的升高水平和持续升高的时间,可以对RV心肌损伤的性质进行评价。  相似文献   
2.
Oral Cancer is one of the five leading sites of cancer in Indian population. The circulating immune complexes were investigated in 100 serum samples of 60 oral cancer patients having different grades of the disease and 40 patients with precancerous lesions obtained from Nair Hospital Dental collage, Mumbai. The results obtained were compared with those of group of 40 healthy blood donors. Elevated levels of Circulating Immune Complexes were observed in oral cancer patients and patients with oral precancerous lesions. 92% positive samples were observed in well differentiated squamous cell carcinoma whereas 100% positive samples were observed in both moderately and poorly differentiated squamous cell carcinoma. Oral leukoplakia and oral submucous fibrosis showed 15% and 90% positivity respectively. Increased level of Circulating Immune complexes in high grade tumor suggest that Circulating Immune complexes is likely to contribute in evaluating the degree of malignancy, but follow up study is needed to draw any conclusion regarding it's prognostic role  相似文献   
3.
摘要:目的: 探讨心脏NRG1在间歇运动激活心梗(myocardial infarction,MI)大鼠心肌NRG1-PI3K/Akt通路抑制心肌细胞凋亡的作用。方法:雄性SD大鼠48只,随机分为假手术组(S),心梗安静组(MI),心梗+间歇运动组(ME),心梗+间歇运动+抑制剂组(MEA),每组12只。采用左冠脉前降支结扎法建立MI模型。S组手术仅穿线不结扎。ME组和MEA组在MI术后1wk进行跑台间歇运动。运动开始速度为10m/min运动10min后,速度逐渐增至25m/min×7 min,再以15 m/min×3min运动,之后依次交替进行。60min×1次/d,5d/1wk×8wk。训练结束后次日,腹腔麻醉,颈动脉插管测定LVSP、LVEDP及±dp/dtmax。之后开胸摘取心脏,进行组织学制片,Masson染色。荧光实时定量PCR测定心肌NRG1及其受体ErbB2/4表达。Western Blot法检测心肌NRG1、ErbB2/4、PI3K/Akt、Bcl-2和Bax蛋白含量。Caspase3表达及TUNEL检测观察分析心肌细胞凋亡情况。结果: MI组胶原容积百分比(CVF)和LVEDP较S组显著升高(P<0.01,P<0.01),LVSP和±dp/dtmax显著降低(P<0.01,P<0.01)。且MI后心肌ErbB4 mRNA表达显著降低(P<0.01),心肌NRG1、ErbB2和ErbB4蛋白表达显著降低(P<0.05,P<0.01,P<0.01),PI3K/Akt蛋白表达及Bcl-2/Bax比值显著降低(P<0.01,P<0.01),TUNEL阳性细胞数和Caspase3活力显著增加(P<0.01,P<0.01)。ME组CVF和LVEDP较MI组显著降低(P<0.01,P<0.01),LVSP和±dp/dtmax显著升高(P<0.01,P<0.01),心肌NRG1、ErbB2和ErbB4 mRNA及蛋白表达均显著增加(P<0.01,P<0.01,P<0.01),PI3K/Akt蛋白表达和Bcl-2/Bax比值显著增加(P<0.01,P<0.01),TUNEL阳性细胞数和Caspase3活力显著降低(P<0.01,P<0.01),且运动效应被抑制剂AG1478显著减弱。结论:间歇运动可通过激活心肌NRG1及其受体表达,上调PI3K/Akt蛋白表达,抑制心肌细胞凋亡和胶原过度增生,改善心功能。  相似文献   
4.
柳华  杨翼 《湖北体育科技》2011,30(6):676-680
心肌肥厚是心脏受到刺激后的一种代偿反应。心肌的生理性肥厚可提高心脏机能,但病理性肥厚则会引起心血管疾病心律失常发病和死亡,亦是运动员发生猝死的原因之一。明确运动性心肌肥厚的机制,可为保护运动员心脏提供理论依据。目前为止,形成心肌肥厚的信号通路包括PKC、蛋白激酶B(Akt)、钙调神经磷酸酶(CaM)、丝裂原活化蛋白激酶...  相似文献   
5.
The main objective of this study is to evaluate the anti-hypertrophic potential of the aqueous extract of Enicostemma littorale (E. littorale) against isoproterenol induced cardiac hypertrophic rat models (male albino Wistar rats) through biochemical investigations. Aqueous extract of E. littorale known for various beneficial properties was administered (100 mg/kg, 12 days, oral) to isoproterenol (ISO) induced cardiac hypertrophic rats (low ISO—60 mg/kg, 12 days and high ISO—100 mg/kg, 12 days, subcutaneous) and were compared with group that was treated with the reference drug, Losartan (10 mg kg, administered for 12 days, oral). The anti-hypertrophic effect of E. littorale was evaluated by analysing the morphometric indices of the heart, ECG tracings, changes in blood biochemical parameters viz., serum glucose, serum total protein, serum albumin, lipid profile, cardiac specific enzymes (SGOT, SGPT and LDH) and histopathological examination of the heart tissue. The results fundamentally revealed that the plant extract efficiently ameliorated cardiac hypertrophy induced by ISO injected in experimental rats. The outcomes of biochemical investigations of this study highlighted the association between the hypertrophic β-adrenergic receptor signalling (β-AR) and the 5′ AMP-activated protein kinase (AMPK)—peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) axis in the metabolism of cardiac fibrosis and hypertrophy. This β-AR/AMPK-PGC1α signalling stem can serve as a key target in ameliorating cardiac hypertrophy through focus on its principal regulators. To add, we also propose that the glycoside, swertiamarin present in this plant with the reported anti-fibrotic potential in liver can be further isolated and evaluated for its anti-hypertrophic potential to treat cardiac hypertrophy.  相似文献   
6.
摘要:目的:观察灌服甲烷水对一次性力竭运动所致大鼠心肌缺血性损伤、心脏组织内氧化应激和炎症因子的影响,探讨其对运动性心肌损伤产生保护作用的可能机制。方法:24只雄性SD大鼠随机分为安静对照组(C组)、运动对照组(EP组)、运动甲烷水组(EM组)。EP组和EM组分别于运动前30 min灌服蒸馏水和甲烷水,之后进行一次性力竭跑台运动。采用化学比色法、ELISA和Luminex xMAP?技术(液态悬浮芯片技术)检测大鼠血清和心肌中生化指标。结果:1)EM组较EP组运动时间显著延长(P<0.01)。2)与C组比较,EP组大鼠血清中IL-1β、IL-6含量极显著升高(P<0.01),心肌eNOS水平显著降低,MDA含量显著升高(P<0.05),3-NT含量极显著性升高(P<0.01);与EP组比较,EM组血清中cTnI水平显著上升,IL-1β、IL-6含量显著下降(P<0.05),大鼠心肌eNOS水平显著升高(P<0.05),SOD活性、T-AOC含量极显著上升(P<0.01),MDA含量、3-NT含量显著降低(P<0.05)。结论:灌服甲烷水提高大鼠运动能力,可能是通过增加心肌eNOS水平,催化NO生成,舒张血管;提高心肌抗氧化能力,改善大鼠心肌氧化应激损伤,从而对运动性心肌损伤具有一定的保护作用。  相似文献   
7.
目的:探讨无脑儿与正常胎儿心脏结构的差异,为畸形胎儿的心脏发育研究提供形态学方面的资料。方法:用H.E染色,通过光镜观察无脑儿及正常胎儿的心脏结构。结果:无脑儿心脏的蒲肯野细胞数量明显低于同龄正常胎儿。结论:无脑儿神经系统发育异常影响其心脏内蒲肯野细胞的发育。  相似文献   
8.
Objective: The beneficial effect of percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) has been well established, but there is the problem of no-reflow phenomenon which is an adverse prognostic factor in primary PCI. In the present study the effect of a distal protection device (PercuSurge GuardWire; GW) on epicardial blood flow and myocardial perfusion was evaluated. Methods and Results: Patients with AMI were randomly divided into 2 groups, the GW and the control groups. The GW group included 52 patients with AMI who underwent primary PCI with GW protection and the control group included 60 patients who underwent primary PCI without GW protection. Epicardial blood flow in the infarct-related artery (IRA) and myocardial perfusion were evaluated according to the thrombolysis in myocardial infarction (TIMI) flow grade and the myocardial blush grade (MBG). We found TIMI score of 3 was obtained significantly more frequently in the GW group (96%) than in the control group (80%). The MBG score of 3 was obtained also significantly greater in the GW group (65%) than in the control group (33%). Conclusion: Primary PCI with GW protection can significantly improve epicardial blood flow and myocardial perfusion.  相似文献   
9.
To study the protective role of Arogh on isoproterenol induced myocardial damage in rats. The effect of Arogh pretreatment on isoproterenol induced myocardial damage was assessed by studying the levels of lipid peroxides and changes in the activity of marker enzymes such as creatine kinase, lactate dehydrogenase and transaminases in serum and heart tissue. In isoproterenol administered rats, a significant decrease was observed in the activity of marker enzymes in the heart with a corresponding increase in their levels in serum. Lipid peroxide levels increased significantly in the serum and heart. In rats pretreated with arogh, the level of lipid peroxides and the activity of marker enzymes were maintained at near normal values. Pretreatment with Arogh offered a protective effect against isoproterenol induced myocardial damage in rats as evidenced by LDH isoenzyme patterm and histopathological studies of heart tissue.  相似文献   
10.
INTRODUCTIONTheNa /H exchanger (NHE)isapH regulatoryproteinpresentintheplasmamem branceofcardiomyocytesandothercelltypes.AlthoughseveralisoformsofNHEhavebeende cribed,thepredominantisoformintheheartistheubiquitousNHE 1 ,whichundercentainphysiologicalconditi…  相似文献   
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