Objective We used ischemic preconditioning method by blocking rabbit's right carotid artery at intervals repeatedly and increasing blocking time to reconstruct collateral circulation. Cerebral protection effects were investigated after the right carotid artery was permanently blocked. Methods 48 rabbits were randomly divided into experimental and control groups (n=24).The right common carotid artery of the animals in the experimental group was compressed at intervals repeatedly. We blocked the right carotid artery blood flow by the Inflatable balloon, ischemic time=number of times×5+40(min), 2 times per day. The longest blocking time is 4 h (20th days). The procedure of control group was the same as that of experimental group, except that the carotid artery blood flow was not blocked. The establishment of a right collateral circulation in the rabbit brain was observed with Digital Subtraction Angiography (DSA) on the 1st, 10th and 20th day respectively. The blood flow in the right common carotid artery was completely blocked at 20th day. The neurological deficit score was observed at 1, 3, 6, 24 h. Then we got brain tissue specimens and compared the brain water content and pathological changes between the two groups. The number of brain microvascular of the corresponding places was also counted. Results During the experiment, no abnormal behaviors such as excitement, agitation, lethargy were observed in either group. DSA showed that contrast medium passed into the right middle cerebral artery Willis ring on the 10th day.Compared with the 1st day, the blood vessels on the right side were much clearer in DSA. On the 20th day there was almost no difference between the left and right sides in vascular imaging. Experimental group's neurological deficit score and water content were lower than those of the control group's (P＜0.05). Observation showed that there were more brain microvascular in the right side (ischemic side) pathological specimens of the experimental group 5.3±0.5 than control group 3.5±0.4 (P＜O.05) under microscope at 400 times. Conclusion By multiple ischemic preconditioning cerebral artery Willis ring and cerebral collateral circulation would be reconstructed, and it had obvious protective effect on cerebral ischemia resulted from completely blocked carotid arteries.

Objective To investigate the effects of hyperoxygen solution(HOS)injected in vein on biochemical indexes of rats with acute carbon monoxide poisoning.Methods Eighteen SD rats were randomly divided into 3 groups,Normal group(N group),carbon monoxide poisoning group(C group)and HOS treatment groups(H15 group).Each contained 6 rats.After exposure of CO poisoning 1 h,C group accepted with balanced salt solution 15 ml/kg and H15 group with HOS 15 ml/kg.CO poisoning model were established by intraperitoneal injection CO with 120 ml/kg.C group and the treatment group were such poisoning rats,while N group were given the same dose of air.At the end of treatments,all the rats were collected 0.5 ml of arterial blood for blood gas measurement and 3 ml of venous blood for the determination of sensitive biochemical indexes in brain,heart,liver,and kidney.Results CO 120 ml/kg with intraperitoneal injection can cause severe hypoxemia after 1.5 h,PaO2 decreased from the(96.62 ± 2.4)nun Hg (1 mm Hg=0.133 kPa)to(43.04±4.13)mm Hg.After CO poisoning for 1 d,C group had test indicators increased significantly including neuron-specific enolase(NSE),troponin(cTnT),creatine kinase(CK),creatine kinase MB(CK-MB),lactate dehydrogenase(LDH),α-hydroxybutyrate dehydrogenase(ct-HBDH),total bilirubin(TBIL),aspartate aminotransferase(AST),alanine aminotransferase(ALT),glutamyl transferase(GGT),blood urea nitrogen(BUN)and creatinine(Cr)(P＜0.01).When intravenous infused with different doses of HOS,Dissolved oxygen in plasma was significantly increased,PaO2 increased from the (43.0± 4.1)mm Hg to(77.1±2.5)mm Hg.All the enzymes were significantly lower than these in C group,although still were significantly higher than these in N group(P＜0.01).Conclusion Intravenous infusion with HOS 15 ml/kg can reduce significantly the biochemical indexes changes caused by acute CO poisoning in rat,and prevent the importance organs from damage.

目的 研究恒磁场对培养的人脐动脉血管平滑肌细胞(VSMC)胞浆内游离钙离子浓度([Ca2+]i)的影响,探讨恒磁场抑制VSMC增殖的作用机制.方法 离体培养人脐动脉VSMC,不同强度的恒磁场垂直作用于VSMC,应用激光共聚焦显微镜观察恒磁场对VSMC胞浆[Ca2+]i的影响.结果 5 mT的恒磁场作用于VSMC后10-50 min[Ca2+]i较对照组明显下降,20 min下降最明显;其平滑肌细胞的Ca2+荧光强度明显弱于对照组,至60 min接近对照组.结论 恒磁场对VSMC胞浆[Ca2+]i有明显降低作用,可能是抑制VSMC细胞增殖的机制.为经皮冠状动脉成型术(PTCA)术后再狭窄的治疗提供了新的理论基础.

目的:观察瑞芬太尼对先天性腭裂修补术患儿血流动力学的影响。方法:选择ASAⅠ～Ⅱ级择期行腭裂修补术的患儿40例,年龄2～14岁,体重8～30kg,随机分为瑞芬太尼组(R组)和芬太尼组(F组),每组20例,麻醉诱导、气管插管成功后接麻醉机行机械通气,R组持续泵入瑞芬太尼和异丙酚;F组以异丙酚泵注,每隔15～20min按1!g/kg缓慢静注追加芬太尼。分别记录患儿诱导前、诱导后2min、气管插管后2min、手术开始后10min时的MAP、HR、SpO2,以及术毕停药后患儿自主呼吸恢复时间、意识恢复时间、苏醒拔管时间。结果:诱导后R组MAP、HR有所下降,但基本保持平稳,而F组MAP、HR均显著下降,波动明显(P<0.05或P<0.01);两组SpO2无显著差异。麻醉后自主呼吸恢复时间、苏醒拔管时间、意识恢复时间R组显著短于F组(P<0.01)。结论:瑞芬太尼比芬太尼镇痛作用强,维持术中血流动力学稳定,术后苏醒快,拔管时间短。