刺五加叶皂甙预处理对供心保存的实验研究

目的观察刺五加叶皂甙 (ASS)预处理对供心保存效果的影响 ,并探讨其机制。方法随机将兔分为对照组 (Control组 ) ;缺血预处理组(IP组) ;ASS预处理组 (ASS组 ) ;格列苯脲加ASS预处理组(Gli+ASS组 ) ;格列苯脲组 (Gli组 )。先行药物预处理 ,再离体灌注 ,停搏 ,4℃保存180min,最后行再灌注。观察心功能 (±dp/dtmax及其恢复率 )、心肌磷酸肌酸激酶 (CK -mb)释放量、心肌ATP含量和能荷(EC)。结果①与Control组比较 ,IP组和ASS组的±dp/dtmax恢复率均增加 ,CK -mb均降低 ,停搏180min的ATP及EC均提高 (P<0.05或P<0.01) ;②Gli+ASS组和Gli组分别与Control组比较 ,±dp/dtmax恢复率 ,CK -mb ,ATP和EC均无明显差异 (P>0.05) ;③Gli+ASS组与ASS组比较 ,±dp/dtmax恢复率 ,CK -mb,停搏180min的ATP、EC差异明显(P<0.05)。结论ASS预处理供心可以发挥和缺血预处理相似的心脏保护作用。开放KATP 是ASS发挥药物预处理作用的重要机制之一。     

国内外中草药吡咯里西啶类生物碱控制情况浅析

吡咯里西啶生物碱(PAs)是一类分布广泛的植物性毒素,具有1,2位双键结构和7、9位酯基取代的PAs具有较强肝毒性(HPAs),其在国内外食品、中草药中的控制得到广泛关注。本文重点阐述蜂蜜、茶产品、中草药等不同产品中PAs前处理方法、检测方法以及相关控制要求,为多种中药材和其他产品中PAs的检测和控制提供参考依据。     

我国城市生活垃圾堆肥技术的工程应用

介绍了高温好氧静态仓式堆肥的前处理和粗堆肥及利用粗堆肥生产复合肥的生产工艺和设备.     

环境中邻苯二甲酸酯类化合物的分析测定

该文概述了环境中邻苯二甲酸酯类化合物的存在现状,综述了不同环境中邻苯二甲酸酯类化合物的前处理方法及其分析测定技术.色谱技术是对环境中邻苯二甲酸酯类化合物进行定性和定量分析测定的主要方法.而色谱分析前的样品制备,包括预分离和预浓缩技术.大气环境样品中邻苯二甲酸酯类化合物的预处理主要采用的是索氏提取、溶液提取和填充柱分离;水环境样品中采用的前处理技术较多,但大多数都是萃取技术;底质和生物试样目前用的较多是微波萃取、超声波萃取和索氏提取.     

磁共振谱成像及其在肿瘤诊疗中的应用

本文在分析磁共振谱成像(MRSI)的特点,以及能够提供的肿瘤病理信息的基础上,就如何在MRI设备上用MRSI技术开展肿瘤诊疗的条件、关键技术和方法进行了介绍,并举例说明,为有意开展这方面工作的医院提供发展思路.     

An associative analysis of pretreatment effects in gustatory conditioning by amphetamine

Various attempts have been made to account for the fact that pertreatment with some pharmacological agents reduces the ability of such agents to induce conditioned aversion to a flavor. One explanation, based on the concept of tolerance, suggests that pretreatment is effective because it renders the animal less sensitive to direct effects of a given dose of the agent. A second explanation emphasizes the possibility that procedural consequences of pretreatment interfere with associability of flavor and drug effect during conditioning. The second explanation was tested in two experiments. In Experiment I nonreinforced presentations of drug administration cues completely reversed the attenuating effects of amphetamine pretreatment on gustatory conditioning by amphetamine. This finding was replicated and extended in the second experiment which was also designed to eliminate an alternative nonassociative explanation for the results. The principle of associative blocking may explain the effect of pretreatment on subsequent gustatory conditioning by drugs.     

葛芩片预处理心肌保护作用机理研究

目的探讨葛芩片预适应增强心肌保护作用的机理。方法采用改良推管法建立大鼠在体心肌缺血预处理模型,原位末端标记法检测细胞凋亡;免疫组化法检测蛋白激酶C(PKC)表达;羟胺法测定血清超氧化物歧化酶(SOD)活性;TBA法测定血清丙二醛(MDA)含量。结果缺血再灌注组心肌凋亡细胞数量显著增加(P<0.01)。预适应组、葛芩片低、中、高剂量预适应组细胞凋亡数均较缺血再灌注组显著减少(P<0.01);葛芩片中、高剂量组细胞凋亡数较预适应组显著减少(P<0.01或P<0.05)。缺血再灌注组PKC表达明显增多(P<0.01);预适应组、葛芩片中、高剂量组PKC表达较缺血再灌注组显著增高(P<0.01)。葛芩片高剂量组MDA含量较缺血再灌注组、预适应组、葛芩片低剂量预适应组显著降低(P<0.01或P<0.05);SOD活性较缺血再灌注组和预适应组显著升高(P<0.01)。结论葛芩片预适应增强作用与其抑制细胞凋亡、提高心肌细胞抗氧化能力有关。     

高碳酸血症预处理对肺缺血-再灌注损伤早期炎症反应的影响

目的观察不同程度高碳酸血症预处理对大鼠肺缺血-再灌注损伤(lung ischemia reperfusion injury,LIRI)的影响。方法雄性SD大鼠50只,2~3月龄,随机分为五组,每组10只。假手术组(S组):开胸后游离左侧肺门,不予其他处理;IR组:采用左肺原位缺血45min,再灌注180min建立大鼠左肺IR模型;L、M、H组:通过调节RR,使P_(ET)CO_2分别达到46~55mmHg(L组)、56~65mmHg(M组)、66~75mmHg(H组),预处理5 min,然后同IR组处理建立大鼠左肺IR模型。缺血-再灌注(ischemia-reperfusion,IR)180min后,采用ELISA法检测血清IL-8和IL-10浓度;处死大鼠,取肺组织标本,采用考马斯亮蓝染色法检测肺泡灌洗液(bronchial alveolar lavage fluid,BALF)中总蛋白(TP)含量,肺组织湿/干重比(W/D)、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性,观察肺组织病理学变化及TNF-α蛋白阳性细胞面积。结果与S组比较,IR、L、M、H组血清IL-8浓度、肺组织病理学评分、肺组织W/D、MDA含量,以及TNF-α蛋白阳性细胞面积百分比明显升高(P0.05),SOD活性明显降低(P0.05)。与IR组比较,L、M、H组血清IL-8浓度、肺组织病理学评分、肺组织W/D、MDA含量,以及TNF-α蛋白阳性细胞面积百分比、SOD活性明显降低(P0.05)。与L组比较,H组以上各项指标均明显降低(P0.05)。IR组血清IL-10浓度明显高于S组(P0.05)。结论通过改变呼吸模式造成高碳酸血症预处理,可以抑制大鼠LIRI后氧自由基爆发和促炎细胞因子生成,降低早期炎症反应水平,减少炎性渗出,对减轻LIRI起到一定的作用,而且在P_(ET)CO_2 46~75mmHg内,随着P_(ET)CO_2升高,作用越强。     

不同穴位重复电针预处理诱导兔脊髓缺血耐受效果的对比

目的:比较不同穴位电针预处理对兔脊髓缺血再灌注损伤保护作用的效果,为临床提供最佳的预处理方案。方法:32只雄性新西兰大白兔随机数字表法分成4组(各组n=8),即对照组、戊巴比妥钠组、委中穴组及足三里穴组。对照组静脉给予生理盐水1mL/kg,连续5d;戊巴比妥钠组静脉给予戊巴比妥钠30mg/kg,连续5d;委中穴和足三里穴组每天在戊巴比妥钠(30mg/kg)麻醉下,电针分别刺激委中穴和足三里穴60min/d,连续5d。最后一次预处理后24h,夹闭肾下腹主动脉20min,制作兔脊髓缺血模型;再灌注后4,8,12,24和48h分别对动物后肢运动功能评分;再灌注48h后,深麻醉下处死动物取脊髓(L5～7),制作标本行组织病理学观察。结果:所有动物均存活,再灌注后48h电针预处理委中穴和足三里穴组后肢运动功能评分及脊髓前角运动神经元计数均明显高于对照组(P=0.001);足三里组后肢运动功能评分和脊髓前角运动神经元计数明显低于委中穴组(P=0.001);对照组与戊巴比妥钠组相比,后肢运动功能评分及脊髓前角神经元计数无显著性差别(P=1.0和P=0.873)。结论:电针预处理对兔脊髓缺血再灌注损伤有显著的保护作用,且刺激委中穴优于刺激足三里穴的效果。     

Non-enzymatic pretreatment of nerve agent (soman) poisoning: a brief state-of-the-art review

The rapid onset of toxic signs following nerve agent intoxication and the apprehension that current therapy (atropine, oxime, diazepam) may not prevent brain damage, requires supportive pretreatment. Since the current pretreatment drug pyridostigmine fails in protecting brain-AChE, more effective pretreatment is necessary.A main focus of present-day pretreatment research is on bioscavengers, another is on centrally active reversible AChE-inhibitors combined with drugs showing anti-cholinergic, anti-glutamatergic, neuroprotective and non-sedating GABA-ergic activity. Strategies aimed at improving efficacy of pharmacological pretreatment will briefly be discussed. Galantamine, given as a pretreatment or stand-alone therapy, emerged as one of the best medical countermeasures against nerve agent poisoning in guinea pigs. Other preclinical studies demonstrated effective pretreatment consisting of physostigmine combined with procyclidine, scopolamine or bupropion (all single injections), against nerve agent poisoning in guinea pigs. A long sign-free pretreatment with physostigmine (Alzet pump), combined with single injection of procyclidine just before soman poisoning, enhanced the efficacy of a post-poisoning therapy consisting of 3 autoinjector equivalents of HI-6, atropine and diazepam, considerably.