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目的 研究蒙药安神补心六味丸对大鼠心肌缺血损伤的保护作用和氧化应激机制。方法 将60只大鼠随机分为空白组、模型组、阳性对照组(丹参滴丸)及蒙药安神补心六味丸低、中、高剂量组,使用腹腔注射异丙肾上腺素方法制备大鼠急性心肌缺血模型,记录并观察大鼠心电图活动变化,然后进行腹主动脉取血,分离血清,测定乳酸脱氢酶(Lactic dehydrogenase,LDH)、肌酸激酶(Creatine kinase,CK)、磷酸肌酸激酶(Creatine kinase isoenzyme,CK-MB)、谷草转氨酶(Aspartate aminotransferase,AST)、超氧化物歧化酶(Superoxide dismutase,SOD)、丙二醛(Malondialdehyde,MDA)和谷胱甘肽过氧化物酶(Glutathione peroxidase,GSH-PX)含量变化。取心肌组织固定,对大鼠心肌组织进行HE染色,通过对心肌酶学和和心肌组织形态学两个方面来考察蒙药安神补心六味丸对大鼠心肌缺血模型的保护作用。结果 与空白组比较,模型组大鼠血清中LDH活性极显著升高(P<0.01),CK、CK-MB、AST、MDA活性均显著升高(P<0.05),SOD活性显著降低(P<0.05),GSH-PX活性高度显著降低(P<0.001),且差异均具有统计学意义;与模型组比较,蒙药安神补心六味丸组高剂量组大鼠血清中LDH、CK、CK-MB、MDA活性显著降低(P<0.05),SOD活性显著升高(P<0.05),GSH-PX活性极显著升高(P<0.01),且差异均具有统计学意义。从HE染色分析,蒙药安神补心六味丸能够改善因缺血而造成的心肌组织损伤。结论 蒙药安神补心六味丸能有效改善心肌组织病理状态,减轻大鼠心肌缺血损伤,以达到保护心肌作用,机制可能与氧化应激机制相关。 相似文献
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龙衍航 《中国继续医学教育》2020,(10):95-97
目的 探讨动态心电图与常规心电图诊断冠心病患者心肌缺血及心律失常的应用效果.方法 选择2015年3月—2017年3月期间医院收治的冠心病患者70例为研究对象,随机分为两组,对照组为常规心电图,观察组为动态心电图.结果 观察组的心肌缺血阳性率低于对照组,阴性率高于对照组,有统计学意义(P<0.05);观察组的房性心律失常、室性心律失常、短阵室上速、房室传导阻滞检出率高于对照组(P<0.05).结论 将动态心电图用于心律失常中能帮助患者早期确诊,临床上可以将动态心电图与常规心电图联合诊断,达到优势互补,提高诊断准确率. 相似文献
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胡芳 《中国继续医学教育》2020,(6):121-124
目的探讨神经节苷脂联合苯巴比妥治疗新生儿缺氧缺血性脑病的临床疗效及对新生儿神经功能的影响。方法选取2017年3月-2019年3月本院收治的缺氧缺血性脑病新生儿106例,随机分为两组,对照组应用苯巴比妥治疗,研究组应用神经节苷脂联合苯巴比妥治疗。比较临床治疗有效率、神经功能恢复效果、治疗前后NBNA评分统计。结果研究组临床治疗有效率、不同程度的时间恢复效果、治疗后NBNA评分均高于对照组(P<0.05)。结论治疗新生儿缺氧缺血性脑病治疗过程当中,神经节苷脂联合苯巴比妥的治疗效果理想,可改善新生儿神经功能。 相似文献
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中青年女性发生冠心病的预后不如男性好,这种现象不能用已经证实的传统的心血管疾病危险因素完全解释。心理应激作为新的危险因素,被广泛证实可诱发可逆的心肌缺血,称之为心理应激性心肌缺血。在缺血性心脏病患者中,心理应激性心肌缺血发生率高且可加重预后转归。与男性患者相比,中青年女性更容易发生心理应激性心肌缺血。最新的研究数据表明微循环障碍可能在中青年女性心理应激性心肌缺血的发生中扮演重要角色。这篇文章首次综述心理应激性心肌缺血与中青年女性冠心病的研究进展。 相似文献
8.
Vishnu Ambur Peter Park John P. Gaughan Scott Golarz Frank Schmieder Paul Van Bemmelen Eric Choi Ravi Dhanisetty 《Journal of vascular surgery》2019,69(2):491-496
Objective
Patient selection for open lower extremity revascularization in patients with chronic kidney disease (CKD) remains a clinical challenge. This study investigates the impact of CKD on early graft failure, postoperative complications, and mortality in patients undergoing lower extremity bypass for critical limb ischemia.Methods
The National Surgical Quality Improvement Program database was queried for all patients with critical limb ischemia from 2012 to 2015 who underwent lower extremity bypass using the targeted vascular set. The glomerular filtration rate was calculated using the Chronic Kidney Disease Epidemiology Collaboration Study equation. CKD categories were determined from the National Kidney Foundation Kidney Disease Outcomes Quality Initiative staging criteria. Patients were classified into three groups: CKD stages 3 or lower (mild to moderate CKD), CKD stages 4 or 5 (severe CKD), and on hemodialysis (HD). Multiple variable analysis was used to examine graft failure, mortality, and postoperative complications.Results
The Surgical Quality Improvement Program database identified 6978 patients who underwent infrainguinal lower extremity arterial bypass during the study period. There were 6101 patients (87.4%) with mild to moderate CKD, 327 (4.7%) with severe CKD, and 550 (7.9%) on HD. Patients with severe CKD and on HD were more likely to have revascularization for tissue loss (54.9% vs 68.8% and 74.7%; P < .01). Patients with severe CKD and those on HD had higher rates of early graft failure, postoperative myocardial infarction, and rates of reoperation. Multiple variable analysis confirmed these results showing that HD was associated with postoperative myocardial infarction, readmission, and increased mortality. It also demonstrated that severe CKD was associated with graft failure (odds ratio [OR], 1.67; 95% confidence interval [CI], 1.12-2.50; P = .01), postoperative myocardial infarction (OR, 2.16; 95% CI, 1.35-3.45; P < .01), and readmission (OR, 1.38; 95% CI, 1.06-1.80; P = .02). Other factors associated with graft failure include functional status (OR, 1.39; 95% CI, 1.08-1.80; P = .01), African American race (OR, 1.72; 95% CI, 1.39-2.13; P < .01), and distal bypass (OR, 1.33; 95% CI, 1.09-1.61; P < .01).Conclusions
CKD is a significant predictor of perioperative morbidity after lower extremity bypass. Patients with severe CKD have worse postoperative outcomes without increased mortality. Those on HD have worse survival and postoperative outcomes. 相似文献9.
Martin R. Späth Malte P. Bartram Nicolàs Palacio-Escat K. Johanna R. Hoyer Cedric Debes Fatih Demir Christina B. Schroeter Amrei M. Mandel Franziska Grundmann Giuliano Ciarimboli Andreas Beyer Jayachandran N. Kizhakkedathu Susanne Brodesser Heike Göbel Jan U. Becker Thomas Benzing Bernhard Schermer Martin Höhne Markus M. Rinschen 《Kidney international》2019,95(2):333-349
10.
Stephania Assimopoulos Nancy Shie Venkat Ramanan Xiuling Qi Jennifer Barry Bradley H. Strauss Graham A. Wright Nilesh R. Ghugre 《NMR in biomedicine》2021,34(1)
Hemorrhage is recognized as a new independent predictor of adverse outcomes following acute myocardial infarction. However, the mechanisms of its effects are less understood. The aim of our study was to probe the downstream impact of hemorrhage towards chronic remodeling, including inflammation, vasodilator function and matrix alterations in an experimental model of hemorrhage. Myocardial hemorrhage was induced in the porcine heart by intracoronary injection of collagenase. Animals (N = 18) were subjected to coronary occlusion followed by reperfusion in three groups (six/group): 8 min ischemia with hemorrhage (+HEM), 45 min infarction with no hemorrhage (I ? HEM) and 45 min infarction with hemorrhage (I + HEM). MRI was performed up to 4 weeks after intervention. Cardiac function, edema (T2, T1), hemorrhage (T2*), vasodilator function (T2 BOLD), infarction and microvascular obstruction (MVO) and partition coefficient (pre‐ and post‐contrast T1) were computed. Hemorrhage was induced only in the +HEM and I + HEM groups on Day 1 (low T2* values). Infarct size was the greatest in the I + HEM group, while the +HEM group showed no observable infarct. MVO was seen only in the I + HEM group, with a 40% occurrence rate. Function was compromised and ventricular volume was enlarged only in the hemorrhage groups and not in the ischemia‐alone group. In the infarct zone, edema and matrix expansion were the greatest in the I + HEM group. In the remote myocardium, T2 elevation and matrix expansion associated with a transient vasodilator dysfunction were observed in the hemorrhage groups but not in the ischemia‐alone group. Our study demonstrates that the introduction of myocardial hemorrhage at reperfusion results in greater myocardial damage, upregulated inflammation, chronic adverse remodeling and remote myocardial alterations beyond the effects of the initial ischemic insult. A systematic understanding of the consequences of hemorrhage will potentially aid in the identification of novel therapeutics for high‐risk patients progressing towards heart failure. 相似文献