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61.
子宫内膜异位症是育龄妇女的常见疾病 ,近年来其发病率有上升趋势 ,研究认为EM发生发展与腹腔氧化作用有关。氧化作用是一种炎症反应 ,EM中巨噬细胞释放的氧化活性物 ,腹腔液中氧化低密度脂蛋白及其产物的增加 ,子宫内膜细胞氧化酶与抗氧化酶的异常表达 ,腹腔液中VitE的消耗 ,均说明EM与腹腔氧化作用有关。本文综述有关研究结果为用抗氧化剂和抗炎症制剂预防EM发生提供新的研究途径  相似文献   
62.
Background : Increased sympathetic activity perioperatively and associated cardiovascular effects play a central role in cardiovascular complications. High thoracic epidural blockade attenuates the sympathetic response, but even with complete pain relief, haemodynamic and endocrine responses are still present. Beta–adrenoceptor blockade is effective in situations with increased sympathetic activity. This study was designed to evaluate the perioperative haemodynamic effect of preoperative βblockade and its influence on the haemodynamic aspects of the surgical stress response.
Methods : Thirty–six otherwise healthy patients undergoing elective thoracotomy for lung resection were randomised doubleblinded to receive either 100 mg metoprolol or placebo preoperatively. Anaesthesia was combined high thoracic epidural block and general anaesthesia. The epidural analgesia was continued during recovery. Patients were monitored with ECG, pulse oximetry, invasive haemodynamic monitoring, arterial blood gases and electrolytes.
Results : After induction of anaesthesia the mean arterial pressure (MAP) decreased in both groups, and decreased further in the placebo group after initiation of the epidural block. The heart rate (HR) was slightly less throughout the observation period after metoprolol. Peroperatively, the only difference in measured haemodynamics was a marginally higher MAP after metoprolol. Postoperative cardiac index (CI) was lower with a lower variability and cardiac filling pressures were slightly higher in the metoprolol group. The oxygen consumption index was higher after placebo throughout the observation period, with no difference in the oxygen delivery.
Conclusion. We found that preoperative β–blockade during combined general anaesthesia and high thoracic epidural blockade stabilised perioperative HR and CI and decreased total oxygen consumption.  相似文献   
63.
Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise99mTc-sestamibi SPET with a 2-day protocol and 180° elliptical rotation. The normalized activity values of99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary.  相似文献   
64.
本实验将大鼠从上海空运至兰州,很快转至高海拔地区,用光镜及电镜观察了亚硒酸钠对大鼠的影响。结果发现在高原环境下大鼠对硒的耐受力减低,引起了大鼠猝死半加得高原缺氧对心肌的损伤,降低了大鼠高原适应性。本文还对其耐受机理进行了初步讨论。  相似文献   
65.
A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO2) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO2 measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O2) which reduces the PFC 19F T1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of 19F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of 19F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO2 maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat.  相似文献   
66.
富氧气体防护下暴发性缺氧大鼠大脑超微病理变化   总被引:1,自引:0,他引:1  
目的 从亚细胞水平观察大鼠在12 000m高度暴发性缺氧及富氧气体防护时大脑顶叶皮质组织超微结构变化,为高空暴发性缺氧的防护和治疗提供理论依据。方法 将24只雄性Wistar大鼠随机分为地面对照组、3000m对照组、12000m暴发性缺氧组、12000m吸90%富氧气体防护组、12000m吸100%氧气防护组、12000m吸50%富氧气体防护组,每组4只。于低压舱内暴露于12000m高度30min,然后将动物即刻处死,取大脑顶叶皮质层组织,制成切片,透射电镜下观察。结果与地面对照组相比,随着吸氧浓度的降低,实验组缺氧程度加重,主要表现为脑组织神经细胞、神经胶质细胞结构模糊不清,核及胞质内线粒体、内质网扩张,突触小泡减少等,以12000m暴发性缺氧组及吸50%氧气防护组明显。结论 吸100%和吸90%富氧气体防护效果是理想的,与地面对照组和3000m对照组的结果无明显差别。  相似文献   
67.
Objective To investigate the roles of lipoxin A4, an endegenous lipid mediator with wide anti-inflammatory fea- tures, in attenuating myocardial ischemia-reperfusion injury and the possible mechanisms. Methods Thirty male KM mice were divid- ed randomly into three groups, 10 in each: ischemia-reperfusion group (group A), lipoxin A4 (0.1 mg/kg) group (group B) and Zn- PP (Zinc protoporphyrin Ⅸ, 25 mg/kg)phus lipoxin A4 (0.1 mg/kg)group (group C). A ischemia-reperfusion heart model was de- veloped by ligating the lift anterior descending branch of the coronary artery. A dine of 10% dehydrated alcohol in 0.2 ml for group A, a dose of isochoric lipoxin A4 for group B and a dose of isochoric ZnPP + lipoxin A4 for group C was infused into the ascending aorta through a catheter, which was kpassing the right common carotid artery, 30 minutes after reperfusion. The concentration of serum TNF-α, activities of serum crestine kinase(CK) and lactate dehydrogenase (LDH), activities of myeloperoxidase (MPO) and malond- ialdehyde (MDA) and the cell apoptosis rate in the myocardial tissue were measured 5 hours after reperfusion. Pathological features of the inflammatory infiltration in the myocardium were also observated.Results As compared with group A, the inflammatoryry infiltra- tion in the ischemic and necrotic regions tithe myocardium was reduced, with group C in the intermediate range. The serum activities of CK and LDH wine significantly lower in group B and C than that in group A, and the lowest activities were detected in group B. Similar findings were observed for MPO, an indicator for neutrophil infiltration, and MDA, an indictor for cell injury caused by oxy- gen radicals, in the myocardium. The concentration of TNF-α and the rate of cadiocyte apoptosis were decreased significantly in group B(P < 0.01). ZnPP, an inhibitor of heine oxygenase (HO)-1, attenusted the above protective effects of lipoxin A4 significantly (P<0.05). Conclusion Lipoxin A4 has protective effects against myocardial ischemia-reperfusion injury, and HO-1 may have a potential role in the protectve mechanisms of lipoxin A4, probably pertly by means of reducing the production of reactive oxygen spe- cies and TNF-α, decreasing the activation and infiltration of neutrophils, alleviating inflammatory damage and avoiding apoptosis.  相似文献   
68.
一种新的正交参数选优法及其在非线性回归分析中的应用   总被引:2,自引:0,他引:2  
非线性回归分析是工程中经常采用的一种用来估计数学模型参数的方法,该方法能否顺利运用与参数初始值的选择有极大关系。本研究提出一种新的正交参数选优法——阻尼正交表法,它不仅可以保证非线性回归分析算法的顺利收敛,而且能够显著提高后者的收敛速度,进而极大改善非线性回归分析算法的应用性能。本研究的数值试验及心肌造影超声心动图定量分析应用实例表明,作为对传统正交参数选优法的一种改进,阻尼正交表法在科学与工程计算或信号与信息处理领域有着很好的应用前景。  相似文献   
69.
Hydroxocobalamin is a rapid and powerful antidote in acute cyanide poisoning. The effects of hydroxocobalamin (0.1, 0.3, and 1 mM) on intrinsic myocardial contractility were studied on isolated rat cardiac papillary muscles (n=10). Whatever the concentration, hydroxocobalamin did not modify the active isometric force and a slight increase in maximum unloaded shortening velocity was noted at 1 mM. Only 0.3 mM significantly impaired contraction-relaxation coupling under low load, suggesting a slight decrease in sarcoplasmic reticulum function. No changes in contraction relaxation coupling under heavy load were noted, suggesting the lack of modification of myofilament calcium sensitivity. These results suggest that hydroxocobalamin does not induce noticeable changes in intrinsic myocardial contractility. An indirect mechanism might be involved in the previously reported decrease in cardiac function at supratherapeutic concentrations of hydroxocobalamin.  相似文献   
70.
溶栓及经皮冠脉腔内成形术治疗急性心肌梗死的疗效分析   总被引:1,自引:0,他引:1  
目的 对比直接冠状动脉腔内成形术 (PTCA)及静脉尿激酶 (UK)溶栓对急性心肌梗死 (AMI)治疗的临床疗效。方法 采用观察性队列研究的方法 ,对 97例AMI患者采用UK溶栓 ,60例AMI患者采用直接PTCA治疗 ,比较两组住院期及随访期的超声心动图 (UCG)和临床结果。结果 住院期间UCG检查室壁运动正常者在PTCA组为 (4 6.0 0 % ) ,高于UK组 (2 4.73 % ) (p =0 .0 2 1) ,矛盾运动发生率PTCA组为 0 ,而UK组为 11.83 %。LVEF在PTCA组为 5 6.88± 10 .47,高于UK组 (5 1.5 8± 10 .97) (p =0 .0 41)。住院期心衰发生率UK组为 3 2 .5 9% ,高于PTCA组 (18.3 3 % ) (p =0 .0 2 9)。随访 13 .3 2± 6.86个月累计心衰发生率UK组为 16.2 8% ,也高于PTCA组 (5 .19% ) (p =0 .0 0 1)。住院期间的病死率UK组为 10 .3 1% ,PTCA组为 5 .0 0 % (p =0 .10 0 )。累计病死率UK组为 15 .5 6% ,明显高于PTCA组 (5 .0 0 % ) (p =0 .0 2 1)。 60岁以上年龄组累计的病死率仍然是UK组 (2 8.99% )高于PTCA组 (10 .3 4% ) (p =0 .0 49)。在随访 3、6、12及 2 4个月时PTCA组的生活质量计分各自为 :5 9.90± 14 .67、74.40± 12 .86、73 .86± 9.70、82 .47± 10 .47均高于同时期UK组的计分 (分别是 5 2 .0 8± 14 .49、65 .0 0± 14 .72、67.0 2  相似文献   
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