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11.
Background: Volatile anesthetic preconditioning (APC) protects against myocardial ischemia-reperfusion (IR) injury, but the precise mechanisms underlying this phenomenon remain undefined. To investigate the molecular mechanism of APC in myocardial protection, the activation of nuclear factor (NF) [kappa]B and its regulated inflammatory mediators expression were examined in the current study.

Methods: Hearts from male rats were isolated, Langendorff perfused, and randomly assigned to one of three groups: (1) the control group: hearts were continuously perfused for 130 min; (2) the IR group: 30 min of equilibration, 15 min of baseline, 25 min of ischemia, 60 min of reperfusion; and (3) the APC + IR group: 30 min of equilibration, 10 min of sevoflurane exposure and a 5-min washout, 25 min of global ischemia, 60 min of reperfusion. Tissue samples were acquired at the end of reperfusion. NF-[kappa]B activity was determined by electrophoretic mobility shift assay. The NF-[kappa]B inhibitor, I[kappa]B-[alpha], was determined by Western blot analysis. Myocardial inflammatory mediators, including tumor necrosis factor [alpha], interleukin 1, intercellular adhesion molecule 1, and inducible nitric oxide synthase, were also assessed by Western blot analysis.

Results: Nuclear factor [kappa]B-DNA binding activity was significantly increased at the end of reperfusion in rat myocardium, and cytosolic I[kappa]B-[alpha] was decreased. Supershift assay revealed the involvement of NF-[kappa]B p65 and p50 subunits. APC with sevoflurane attenuated NF-[kappa]B activation and reduced the expression of tumor necrosis factor [alpha], interleukin 1, intercellular adhesion molecule 1, and inducible nitric oxide synthase. APC also reduced infarct size and creatine kinase release and improved myocardial left ventricular developed pressure during IR.  相似文献   

12.
Background: Adenosine triphosphate-regulated potassium channels mediate protection against myocardial infarction produced by volatile anesthetics and opioids. We tested the hypothesis that morphine enhances the protective effect of isoflurane by activating mitochondrial adenosine triphosphate-regulated potassium channels and opioid receptors.

Methods: Barbiturate-anesthetized rats (n = 131) were instrumented for measurement of hemodynamics and subjected to a 30 min coronary artery occlusion followed by 2 h of reperfusion. Myocardial infarct size was determined using triphenyltetrazolium staining. Rats were randomly assigned to receive 0.9% saline, isoflurane (0.5 and 1.0 minimum alveolar concentration [MAC]), morphine (0.1 and 0.3 mg/kg), or morphine (0.3 mg/kg) plus isoflurane (1.0 MAC). Isoflurane was administered for 30 min and discontinued 15 min before coronary occlusion. In eight additional groups of experiments, rats received 5-hydroxydecanoic acid (5-HD; 10 mg/kg) or naloxone (6 mg/kg) in the presence or absence of isoflurane, morphine, and morphine plus isoflurane.

Results: Isoflurane (1.0 MAC) and morphine (0.3 mg/kg) reduced infarct size (41 +/- 3%; n = 13 and 38 +/- 2% of the area at risk; n = 10, respectively) as compared to control experiments (59 +/- 2%; n = 10). Morphine plus isoflurane further decreased infarct size to 26 +/- 3% (n = 11). 5-HD and naloxone alone did not affect infarct size, but abolished cardioprotection produced by isoflurane, morphine, and morphine plus isoflurane.  相似文献   

13.
目的探讨儿童孤独症(CA)与多巴胺转运体(DAT1)440bp等位基因的关系。 方法陕西省纺织医院等于2004年3~8月,采用PCR技术对来自西安市两所康复中心的汉族CA儿童与DAT1基因多态性进行遗传关联分析。 结果(1)DAT1基因多态性中共观察到5种等位基因(320bp,360bp,440bp,480bp,520bp),6种基因型(480/480,480/320,520/480,480/360,480/440,440/440)。(2)使用相对危险度RR对CA与DAT1基因多态性的等位基因和基因型进行关联分析,显示480/440基因型和等位基因440与CA呈正关联,相对危险度分别为265和230,480/480基因型和等位基因480与CA呈负关联,相对危险度分别为064和077。但统计结果没有发现具有统计意义的差异。 结论中国汉族CA儿童与DAT1440bp等位基因无遗传关联。也许等位基因440bp与基因型480bp/440bp这两个因素是发病的风险因素,还有待今后的进一步研究。  相似文献   
14.
本文目的是检验一种用于量化和预测内镜检查患者的不良体验的一种问卷调查的可靠性。分别给予目前常规接受内镜检查的患者2份问卷(操作前及操作后)。第1份问卷包括人口统计学资料、既往内镜检查史、用药或饮酒史、患者期望值、操作前的焦虑及紧张程度。内镜检查后,重新确定患者的耐受性和意愿。内镜检查后对患者进行重复内镜检查的总体满意度或不情愿的主要结果评分≥5确定为“内镜检查的不良体验”(A EE)。148例受试者中有13例报告有AEE。通过对与不良反应如疼痛、紧张和操作期间的损伤情况明显相关的可靠分析,确定测定主要结果的项目。…  相似文献   
15.
16.
王旭华 《九江医学》2003,18(4):214-214
腋路臂丛阻滞广泛用于上肢手术麻醉,由于支配上肢各神经在腋鞘中解剖位置关系,往往桡神经阻滞不全。笔者从2001年始应用“二针三分法”阻滞,与传统的腋路臂丛阻滞比较,取得满意的效果,现报告如下。  相似文献   
17.
Background: A multidisciplinary effort was undertaken to determine whether patients could safely bypass the postanesthesia care unit (PACU) after same-day surgery by moving to an earlier time point evaluation of recovery criteria.

Methods: A prospective, outcomes research study with a baseline month, an intervention month, and a follow-up month was designed. Five surgical centers (three community-based hospitals and two freestanding ambulatory surgical centers) were utilized. Two thousand five hundred eight patients were involved in the baseline period, and 2,354 were involved in the follow-up period. Outcome measures included PACU bypass rates and adverse events. Intervention consisted of a multidisciplinary educational program and routine feedback reports.

Results: The overall PACU bypass rate (58%) was significantly different from baseline (15.9%, P < 0.001), for patients to whom a general anesthetic was administered (0.4-31.8%, P < 0.001), and for those given other anesthetic techniques (monitored anesthesia care, regional or local anesthetics; 29.1-84.2%, P < 0.001). During the follow-up period, the average (SD) recovery duration for patients who bypassed the PACU was significantly shorter compared to that for patients who did not bypass, 84.6 (61.5) versus 175.1 (98.8) min, P < 0.001, with no change in patient outcome. Patients receiving only short-acting anesthetics were 78% more likely (P < 0.002) to bypass the PACU after adjusting for various surgical procedures.  相似文献   

18.
目的:探讨正常青少年膝关节软骨的MRI表现。方法:使用GE 0.2T低场磁共振成像机,采用膝关节线圈,对膝关节行矢状面扫描,应用序列为梯度回波序列T2WI、自旋回波T1WI、自旋回波T2WI、脂肪抑制序列、质子密度序列。翻转角200。扫描野16cm。层厚4mm,间隔1mm。结果:膝关节矢状位MRI梯度回波序列T2WI。和质子密度序列中,股骨髁与胫骨平台的骺软骨MRI能显示出3层不同的信号强度。结论:MRI能准确地显示膝关节软骨的层次结构,为临床诊断膝关节疾病提供参考依据。  相似文献   
19.
目的:评估子宫肌瘤患者经子宫动脉栓塞术(UAE)治疗后临床症状严重程度、健康相关生活质量(HRQOL)的变化及对治疗满意度的调查。设计:对1998~2002年80例经UAE治疗的子宫肌瘤患者进行问卷调查,了解治疗的有效性、治疗前后的临床症状严重程度及HRQOL的变化。主要观察指标:UAE治疗后症状严重程度及HRQOL评分的变化。次要观察指标:患者满意度及子宫体积缩小程度。结果:64例(80.0%)患者完成了问卷,调查时间为UAE后平均32.1月(范围:57.5~6月)。UAE后子宫体积平均缩小26.3%(95%CI19.6~33.0),79例患者中17例(21.5%)于术后平均18.6月…  相似文献   
20.
Background: The study evaluated the efficacy of recombinant human antithrombin (rhAT) for restoring heparin responsiveness in heparin resistant patients undergoing cardiac surgery.

Methods: This was a multicenter, randomized, double-blind, placebo-controlled study in heparin-resistant patients undergoing cardiac surgery with cardiopulmonary bypass. Heparin resistance was diagnosed when the activated clotting time was less than 480 s after 400 U/kg heparin. Fifty-four heparin-resistant patients were randomized. One cohort received 75 U/kg rhAT, and the other received normal saline. If the activated clotting time remained less than 480 s, this was considered treatment failure, and 2 units fresh frozen plasma was transfused. Patients were monitored for adverse events.

Results: Only 19% of patients in the rhAT group received fresh frozen plasma, compared with 81% of patients in the placebo group (P < 0.001). During their hospitalization, 48% of patients in the rhAT group received fresh frozen plasma, compared with 85% of patients in the placebo group (P = 0.009). Patients in the placebo group required higher heparin doses (P < 0.005) for anticoagulation. There was no increase in serious adverse events associated with rhAT. There was increased blood loss 12 h postoperatively (P = 0.05) with a trend toward increased 24-h bleeding in the rhAT group (P = 0.06). There was no difference between the groups in blood and platelet transfusions.  相似文献   

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