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71.
利用协方差分析将那些认为很难控制的因素,即患者入院时的BI得分或NIHSS得分作为协变量x,在排除协变量x对观测变量y,即治疗90天后患者的BI、NIHSS得分影响的条件下,分析治疗方法对治疗90天后患者的BI、NIHSS得分的影响,从而更加准确地对治疗方法进行评价.  相似文献   
72.
Interleukin-1β (IL-1β), a product of the NLRP3 inflammasome, modulates cardiac contractility and diastolic function. We proposed that OLT1177® (dapansutrile), a novel NLRP3 inhibitor, could preserve contractile reserve and diastolic function after myocardial infarction (MI). We used an experimental murine model of severe ischemic cardiomyopathy through the ligation of the left coronary artery without reperfusion, and after 7 days randomly assigned mice showing large anterior MI (>4 akinetic segments), increased left ventricular (LV) dimensions ([LVEDD] > 4.4 mm), and reduced function (LV ejection fraction < 40%) to a diet that was enriched with OLT1177® admixed with the chow in the diet at 3.75 g/kg (Group 1 [n = 10]) or 7.5 g/kg (Group 2 [n = 9]), or a standard diet as the no-treatment control group (Group 3 [n = 10]) for 9 weeks. We measured the cardiac function and contractile reserve with an isoproterenol challenge, and the diastolic function with cardiac catheterization at 10 weeks following the MI surgery. When compared with the control (Group 3), the mice treated with OLT1177 (Group 1 and 2) showed significantly greater preservation of their contractile reserve (the percent increase in the left ventricular ejection fraction [LVEF] after the isoproterenol challenge was +33 ± 11% and +40 ± 6% vs. +9 ± 7% in the standard diet; p < 0.05 and p < 0.005 for Group 1 and 2, respectively) and of diastolic function measured as the lower left ventricular end-diastolic pressure (3.2 ± 0.5 mmHg or 4.5 ± 0.5 mmHg vs. 10.0 ± 1.6 mmHg; p < 0.005 and p < 0.009 respectively). No differences were noted between the resting LVEF of the MI groups. These effects were independent of the effects on the ventricular remodeling after MI. NLRP3 inflammasome inhibition with OLT1177® can preserve β-adrenergic responsiveness and prevent left ventricular diastolic dysfunction in a large non-reperfused anterior MI mouse model. OLT1177® could therefore be used to prevent the development of heart failure in patients with ischemic cardiomyopathy.  相似文献   
73.
脑出血与脑梗塞患者脑脊液中微量元素含量的比较及意义   总被引:2,自引:0,他引:2  
为比较脑出血和脑梗塞后脑脊液中5种微量元素的变化,用等离子体发射光谱仪测定了两种脑卒中患者脑脊液中的Zn、Cu、Fe、P、Ca含量。结果表明,脑出血组脑脊液中5种微量元素含量均高于脑梗塞组。提示脑出血在急性期对脑组织的破坏可能比脑梗塞严重;脑出血对神经细胞兴奋性的升高可能较脑梗塞严重。  相似文献   
74.
@@@@目的探讨体表心电图aVR和V1 ST段相对抬高程度对左主干病变引起的急性心肌梗死的诊断价值。方法回顾性分析因急性心肌梗死住院而行冠状动脉造影的29例患者的心电图,按左主干病变程度分为两组,严重病变(狭窄≥70%狭窄)组(18例);普通病变(狭窄<70%)组(11例)。通过分析心电图aVR和V1 ST段抬高程度与左主干病变的关系,计算以心电图出现STaVR>STV1预测重度左主干狭窄引起急性心肌梗死的敏感性、特异性、阳性预测值及阴性预测值。结果18例冠状动脉造影诊断重度左主干病变组患者中有7例心电图呈STaVR>STV1,其中1例为孤立性左主干病变,诊断敏感性为38.9%;普通病变组中1例前降支合并回旋支狭窄心电图呈STaVR>STV1,诊断特异性为90.9%,阳性预测值87.5%,阴性预测值47.6%。结论 STaVR>STV1诊断左主干病变特异性较高,但敏感性较差,该心电图征象有助于识别急性冠状动脉综合征中的高危患者。  相似文献   
75.
76.
We aim to describe the metabonomic characteristics of myocardial infarction rats. High‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry was utilized to develop a metabonomic method of the heart homogenates of myocardial infarction rats. Hydrophilic interaction chromatography allows the analysis of high polar metabolites, providing complementary information to reversed‐phase liquid chromatography. We combined reversed phase and hydrophilic interaction chromatographic separations to analyze 18 samples, ten from myocardial infarction rat hearts and eight from normal rat hearts. A total of 16 potential biomarkers in rat heart tissue were screened out, primarily related to oxidative stress, nitric oxide damage, taurine, and hypotaurine metabolism and sphingolipid metabolism. This research showed that a comprehensive metabonomic study is a useful tool to reveal the underlying mechanism of myocardial infarction.  相似文献   
77.
复方丹参滴丸抗急性心肌梗死代谢组学研究   总被引:2,自引:0,他引:2  
采用左冠状动脉前降支结扎的方法,建立SD大鼠急性心肌梗死(Acute myocardial infarction, AMI)模型,使用超高效液相色谱-串联四极杆/飞行时间质谱(UPLC-QTOF/MS)代谢组学研究平台对大鼠血浆样本进行代谢轮廓分析,研究复方丹参滴丸对AMI大鼠心肌保护作用机制.经主成分分析和偏最小二乘法分析,筛选并鉴定出22种与AMI相关的差异代谢物,其中的8种能够被复方丹参滴丸显著调节,分别是硫酸对甲苯、马尿酸、雌马酚葡萄糖苷酸、溶血磷脂胆碱(16∶0)、胆酸、油酸酰胺、棕榈酰胺和鞘脂(d18∶1/16∶0).研究结果表明, 复方丹参滴丸可能是通过调节苯丙氨酸代谢、甘油磷脂代谢、脂肪酸代谢、胆汁酸代谢及鞘脂代谢通路,发挥抗AMI大鼠心肌损伤的作用.  相似文献   
78.
Jiang Z  Sun J  Liang Q  Cai Y  Li S  Huang Y  Wang Y  Luo G 《Talanta》2011,84(2):298-304
Cerebral infarction is always of sudden onset, and usually leading to serious consequence. It is of therapeutic significance to develop fast and accurate diagnosis methods for cerebral infarction so that patients can be treated timely and properly. A metabonomic approach was then proposed to investigate the potential biomarkers and metabolic pathways associated with cerebral infarction and also establish a prediction model of cerebral infarction for the fast diagnosis. Serum metabolic profiling of sixty-seven cerebral infarction patients and sixty-two controls was obtained using UPLC-TOF MS. The resulting data were then processed by multivariate statistical analysis to graphically demonstrate metabolic variations. The PLS-DA model was validated with cross validation and permutation tests to assure the model's reliability, and significant difference was obtained between the original and hypothetical models (p < 0.0001). A series of endogenous metabolites in the one-carbon cycle, such as folic acid, cysteine, S-adenosyl homocysteine and oxidized glutathione, were determined as potential biomarkers of cerebral infarction. A prediction model developed using PLS-KNN algorithm was established to differentiate cerebral infarction patients from controls, and an average accuracy of 100% was obtained. In conclusion, metabonomic approach is a powerful tool to investigate the pathogenesis of stroke and is expected to be developed as a useful method for the fast diagnosis.  相似文献   
79.
Notoginseng and safflower are commonly used traditional Chinese medicines for benefiting qi and activating blood circulation. A previous study by our group showed that the compatibility of the effective components of total saponins of notoginseng (NS) and total flavonoids of safflower (SF), named NS–SF, had a preventive effect on isoproterenol (ISO)-induced myocardial infarction (MI) in rats. However, the therapeutic effect on MI and the synergistic mechanism of NS–SF are still unclear. Therefore, integrated metabolomics, combined with immunohistochemistry and other pharmacological methods, was used to systematically research the therapeutic effect of NS–SF on MI rats and the synergistic mechanism of NS and SF. Compared to NS and SF, the results demonstrated that NS–SF exhibited a significantly better role in ameliorating myocardial damage, apoptosis, easing oxidative stress and anti-inflammation. NS–SF showed a more significant regulatory effect on metabolites involved in sphingolipid metabolism, glycine, serine, and threonine metabolism, primary bile acid biosynthesis, aminoacyl-tRNA biosynthesis, and tricarboxylic acid cycle, such as sphingosine, lysophosphatidylcholine (18:0), lysophosphatidylethanolamine (22:5/0:0), chenodeoxycholic acid, L-valine, glycine, and succinate, than NS or SF alone, indicating that NS and SF produced a synergistic effect on the treatment of MI. This study will provide a theoretical basis for the clinical development of NS–SF.  相似文献   
80.
急性心肌梗死患者血清中镉铅铍含量的研究   总被引:1,自引:1,他引:0  
为急性心肌梗死患者的防治提供新的科学依据,对135例急性心肌梗死患者,取其肘静脉血清,用JY-70(Ⅱ)合并型等离子体发射光谱仪 测定微量元素含量,与对照组进行对比分析。结果显示,心肌梗死患者血清铍的含量高于对照组, 而血清镉和铅的含量低于对照组。  相似文献   
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