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1.
目的探讨常温及低温体外循环心脏直视手术对细胞因子及补体的影响。方法选择先天性和风湿性心脏病患者40例,随机分为常温组及低温组各20例,分别于术晨、体外循环结束时及术后1、4、7、14 d抽取患者静脉血标本,测定血浆TNF、IL-2、C3、C4值。结果两组术前各项检查指标无显著差异。(1)两组术后1~4 d的IL-2水平较术前显著下降,至术后7 d恢复正常。体外循环结束至术后4 d,低温组IL-2显著低于常温组。(2)体外循环结束时以及术后1、4、7 d,常温组TNF水平显著低于低温组。两组体外循环结束时及术后1、4 d均高于术前,常温组至术后7 d、低温组术后14 d恢复正常。(3)体外循环结束时及术后1、7 d,常温组C3水平高于低温组,术后4 d两组无差别;常温组及低温组于体外循环结束时、术后1、4 d均低于术前,至术后7 d常温组恢复正常,低温组至术后14 d恢复至术前水平。(4)两组体外循环结束时及术后1、4 d C4水平均低于术前。体外循环结束时、术后1 d,常温组C4水平高于低温组。结论常温体外循环心脏直视手术对细胞因子及补体的影响显著轻于低温组,因而对术后机体的恢复优于低温方法。 相似文献
2.
QIN Jian LIU Hong-jian DENG Wei WU Guo-zhen CHEN Shu-qing JING Ming-hua 《中国生物医学工程学报(英文版)》2005,14(3):114-119
Based on the fuzzy characteristic of the pulse state and syndromes differentiation thinking mode of TCM, an information fusing recognition method of pulse states based on SFNN (Stochastic Fuzzy Neural Network) is presented in this paper. With the learning ability in parameters and structure, SFNN fuses the measurement information of three pulse-state sensors distributed in Cun, Guan, and Chi location of body for the pulse state recognition. The experimental results show that the percentage of correct recognition with new method is higher than that by single-data recognition one, with fewer off-line train numbers. 相似文献
3.
Objective: To investigate the anti-inflammatory effect of erythropoietin (EPO) pretreatment on cardiomyocytes exposed to hypoxialreoxygenation injury (H/R) and explore the possible mechanism.
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect. 相似文献
Methods: The cultured neonatal rats' ventricular cardiomyocytes were divided randomly into 4 groups, control group (C group), EPO pretreatment group (E group), EPO and pyrrolidine dithiocarbamate (PDTC) pretreatment group (EP group) and PDTC pretreatment group (P group). After 24 hours' pretreatment, the cardiomyocytes were exposed to H/R. After pretreatment and H/R, the expression of tumor necrosis factor- α (TNF- α ) gene in all the groups was detected by RT-PCR and Western blot. The nuclear factor- κ B (NF- κB) activity was detected by electrophoretic mobility shift assay (EMSA) and the inhibitor- κB α (Ⅰ- κB α) protein level was detected by Western blot.
Results: The decrement of Ⅰ- κB a protein and the increasing NF- KB activity were found in cardiomyocytes pretreated with EPO before H/R compared to other groups (t=3.321, 4.183, P〈0.01). However, after H/R, NF- κB activity and expression of TNF- α gene were significantly reduced, Ⅰ- κB a protein expression was increased in cardiomyocytes of E group compared to other groups (t=-3.425, 3.687, 3.454, P〈0.01). All theses changes caused by EPO pretreatment were eliminated by the intervention of PDTC (an antagonist to NF- κB) during pretreatment.
Conclusions: EPO pretreatment can inhibit the activation of NF- κB and upregulation of TNF- α gene in cardiomyocytes exposed to H/R through a negative feedback of NF- κB signaling pathway, and thus produces the anti-inflammatory effect. This might be one of the ways EPO produces the anti-inflammatory effect. 相似文献
4.
广东省中山市黄圃人民医院始建于1956年,迄今已有四十多年的历史。近年来,在各级政府的亲切关怀和卫生主管部门的大力支持下,医院乘改革开放的春风,全院上下团结携手,艰苦奋斗,积极进取,励精图治,走出了一条自我发展、自我完善之路,在临床治疗、专科建设上逐步形成了自己的风格和特色,取得了较好的社会效益和经济效益。1994年获国家级爱婴医院称号,1995年被省卫生厅评为二级甲等医院,1998年顺利通过市档案局评审, 相似文献
5.
中华眼镜蛇毒F组分对沙鼠脑缺血再灌注损伤的保护作用 总被引:1,自引:1,他引:0
目的:研究中华眼镜它毒F组分脑缺血再灌注损伤的保护作用,方法:结扎沙鼠双侧颈总动脉1h,造成前脑缺血模型,用比色法测定脑匀浆过氧化脂质的最终产物丙二醛(MDA)的含量及超氧化物歧化酶(SOD)的活性,结果:F组分0.9,0.3,0.1mg/kg可显著抑制脑内脂质过氧化,降低MDA的含量,并提高超化物歧化酶的活,性且呈一定的量效关系,同缺血再灌组比较P<0.05,同阳性对照药尼莫通比较,P>0.05,结论:中华眼镜蛇毒F组分对脑缺血再灌注损伤有保护作用,可能与抑制自由基的生成和促进自由基的清除有关。 相似文献
6.
采用化学共沉淀法制备锑掺杂二氧化锡(ATO)超细导电粉体,研究了反应温度,滴定终点pH值,掺锑量及锻炼温度对粉体导电性的影响,并对实验结果进行了讨论。 相似文献
7.
目的:鉴别益母草中是否含阿魏酸,方法:采用薄层色谱法和高效液相色谱法鉴别不同提取溶煤制备的样品,结果:从益母草中能检出阿魏酸。结论:益母草中可能含游离的阿魏酸,以5%Na2CO3溶液替代药典中的甲醇提取,方法简化,稳定性高,重现性好。 相似文献
8.
骨骼肌肌细胞增殖及分化过程中凋亡现象 总被引:7,自引:4,他引:3
目的 对骨骼肌分化中的凋亡现象进行初步研究,方法 本实验采用体外培养的C2C12肌母细胞分化模型,用流式细胞仪检测肌细胞分化过程中细胞周期的变化,提取细胞基因组DNA进行电泳分析,用原位末端标记法进行了凋亡细胞染色,电子显微镜观察凋亡小体的形成。结果 C2C12细胞在肌分化诱导24h和48h,检测出凋亡现象;而对照组、肌分化诱导72h组均未检出凋亡现象。结论 在肌肉分化、发育的过程中,某些细胞会按自身程序主动死亡,以凋亡细胞的形式排除。而且具有明显的时间性,终末分化的肌管不易出现凋亡。 相似文献
9.
饲养层对胚胎干细胞(Embryonic stem cell,ES cell)的培养与建系十分重要。实验选择小鼠原代成纤维细胞(Priimary mouse embmy fibroblasts,PMEF)作为饲养层,这种饲养层能够较好地维持ES细胞未分化状态和二倍体核型。除选用经典的14.5d的孕鼠制做原代成纤维细胞外,我们还选了10d、18d、的孕鼠制成饲养层,通过ES-D3的传代培养结果表明:10-18d的PMEE均可作为饲养层用,10代内的饲养层培养细胞均适宜。 相似文献
10.
本文就硒的生理作用,缺乏硒的临床表现,硒代谢异常与各种疾病的关系,硒在营养支持中的作用补充本时的注意事项进行了综述,旨在进一步阐明硒在营养支持中的作用。 相似文献