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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.
Preoperative metoprolol improves cardiovascular stability and reduces oxygen consumption after thoracotomy 总被引:1,自引:0,他引:1
C.–J. JAKOBSEN S. BILLE P. AHLBURG L. RYBRO K. D. PEDERSEN B. RASMUSSEN 《Acta anaesthesiologica Scandinavica》1997,41(10):1324-1330
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
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.
采用超微结构细胞化学和计算机图象定量分析方法,测量计算了高压下氧中毒小鼠肺毛细血管线粒体、线粒体细胞色素氧化酶二维形态学和三维立体学参数。结果表明,小鼠暴露于0.5MPa高压氧后,肺毛细血管线粒体二维形态学和三维立体学参数的值没有发生变化,但线粒体细胞色素氧化酶的活性明显降低。 相似文献
64.
Ronald G. Pratt Jie Zheng Brent K. Stewart Yoseph Shiferaw Anthony J. McGoron Ranasinghage C. Samaratunga Stephen R. Thomas 《Magnetic resonance in medicine》1997,37(2):307-313
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
65.
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
66.
本文针对目前医疗氧舱自动化程度不高,各种治疗参数难以定量控制的特点,设计出了以微型计算机为控制核心的医疗氧舱自动供排气系统,并重点介绍了微型计算机的硬件和软件设计。 相似文献
67.
目的:观察高压氧结合针灸治疗脑外伤患者的疗效。方法:对96例脑外伤患者采用高压氧、针灸配合药物进行综合治疗。同时,对83例对照组患者根据病情给予降颅压、抗感染、改善脑供血、保护脑细胞等治疗,有手术指征者行清除血肿、减压和清创术。结果:出院时两组患者功能比较,治疗组明显优于对照组,有显著性差异(P<0.O1),疗效治疗组也明显好于对照组。结论:高压氧结合针灸治疗能够明显提高脑损伤患者疗效,对肢体功能有明显提高。 相似文献
68.
T. KRANTZ F. SZTUK F. SWIATEK J. JACOBSEN N. H. SECHER 《Acta anaesthesiologica Scandinavica》1997,41(6):719-724
Background: We evaluated the ability of the standards issued by the Danish Society of Anaesthesiologists to reflect a blood loss.
Methods: In 9 pigs bled (0–24 ml kg-1 ) and retransfused (to 28 ml kg-1 ) during halothane anaesthesia, central cardiovascular, thoracic electrical impedance (TI), oxygen, acid-base and temperature variables were recorded.
Results: With the recommendation for minor surgery (mean arterial pressure (MAP) and heart rate (HR)), the correlation to the blood loss was 0.74 ( P < 0.001) and with that for major surgery (MAP, HR, central venous pressure (CVP) and rectal temperature (Tempr )) it was 0.79 ( P < 0.001). With the recommendation for extensive surgery (MAP, HR, CVP, pulmonary artery catheter variables and the central-peripheral temperature difference (ΔTempr-t )), the correlation was 0.84 ( P < 0.001). Non-invasive monitoring (MAP, HR, ΔTempr-t TI and near-infrared spectroscopy of the brain (Sinvos O2 )) was only slightly better than basal monitoring (r=0.76, P < 0.001). However, adding arterial base excess (BE), TI and peripheral temperature (Tempt ) to the recommendation for major surgery resulted in a correlation of 0.87 ( P < 0.001), while adding BE and TI to the recommendation for extensive surgery raised correlation to only 0.88 ( P < 0.001).
Conclusion: When the recommendations were followed the correlation to the blood loss ranged from 0.74–0.84. However, with the recording of MAP, HR, CVP, ΔTempr-t, BE and TI a correlation of 0.87 was achieved, indicating that a pulmonary artery catheter may not be in need for patients undergoing surgical procedures with expected haemorrhage. 相似文献
Methods: In 9 pigs bled (0–24 ml kg
Results: With the recommendation for minor surgery (mean arterial pressure (MAP) and heart rate (HR)), the correlation to the blood loss was 0.74 ( P < 0.001) and with that for major surgery (MAP, HR, central venous pressure (CVP) and rectal temperature (Temp
Conclusion: When the recommendations were followed the correlation to the blood loss ranged from 0.74–0.84. However, with the recording of MAP, HR, CVP, ΔTemp
69.
70.
Improvement of oxygen metabolic reserve after extracranial-intracranial bypass surgery in patients with severe haemodynamic insufficiency 总被引:8,自引:0,他引:8
Summary The effectiveness of extracranial-intracranial arterial bypass (EC-IC bypass) surgery on impaired haemodynamic status was studied in 12 patients with reduced regional cerebral perfusion pressure (rCPP) and elevated regional oxygen extraction fraction (rOEF) in the area distal to the symptomatic arterial lesion. Postoperative positron emission tomography (PET) study demonstrated a statistically significant decrease of rOEF in the operated hemispheres with disappearance of the pre-operative interhemispheric rOEF difference. Regional cerebral blood flow (rCBF) and regional cerebral oxygen metabolism (rCMRO2) were also increased in the operated hemispheres with disappearance of the pre-operative interhemispheric differences. Regional CBF/regional cerebral blood volume (rCBV) ratios of the symptomatic hemispheres were increased after surgery, but were still lower than in the contralateral hemispheres. We conclude that EC-IC bypass surgery improves impaired cerebral oxygen metabolic reserve. 相似文献