小鼠病毒性心肌损伤模型制作及cTnⅠ基因扩增与测序分析

目的分析心肌型肌钙蛋白(cTnⅠ)-mRNA在监测病毒性心肌损伤发生与发展过程中的价值.方法于BALB/c小鼠腹腔接种1×108TCID50柯萨奇病毒B3(CVB3)诱发心肌损伤,分别在CVB3感染后第3、6、9、12、15、18和21天采集外周血后处死小鼠,留取鼠心脏作病理组织学检查,以逆转录-聚合酶链反应(RT-PCR)分析心肌和外周血中cTnⅠ基因及测序分析扩增片段.结果CVB3感染后,鼠心肌组织及循环血中cTnⅠ-mRNA均表达增加,且与心肌细胞肿胀、炎性细胞浸润、核固缩及碎裂、变性、坏死、钙化等组织学改变相关.cTnⅠ-mRNA基因扩增,心肌组织全数阳性;外周血阳性率在对照组及感染后的第3、6、9、12、15、18和21天分别为0、0、0、16.7%、40%、71.4%、83.3%和87.5%.测序分析证实从心肌组织及外周血中扩增基因片段与原序列完全一致.结论病毒性心肌损伤时cTnⅠ-mRNA上调表达并释放入血,循环血cTnI-mRNA为监测心肌损伤发生与发展的灵敏标志物.     

血清心肌肌钙蛋白I对急性病毒性心肌炎心肌损伤诊断的价值

目的:探讨病毒性心肌炎(VMC)小鼠血清心肌肌钙蛋白I(cTnI)含量与心肌组织病理改变的关系,为临床诊断VMC心肌损伤提供依据.方法:用柯萨奇B3亲心肌病毒株(CVB3m)制备小鼠VMC模型;分别于感染病毒后第8、15天及第3个月,观测VMC小鼠血清cTnI含量、心肌坏死病理组织学积分(HSN)和心肌炎症组织学积分(HSI),并探讨其相互关系.结果: VMC小鼠心肌损伤以感染后第8天最为显著(P<0.05),此时血清cTnI含量与HSN(r=0.696,P<0.05)及HSI(r=0.760, P<0.05)之间呈正相关.结论:血清cTnI能确切地反映急性期VMC小鼠心肌损伤的程度,是VMC心肌损伤的可靠而敏感的检测指标.     

小鼠病毒性心肌炎中Fas/FasL异常表达的研究

目的探讨柯萨奇病毒B3(CVB3)所致小鼠病毒性心肌炎(VM)心肌细胞损伤的变化,观察Fas/FasL介导的细胞凋亡在心肌损伤中的作用.方法采用CVB3制备小鼠病毒性心肌炎动物模型,心肌组织切片HE染色了解心肌损伤情况;电镜检测观察心肌组织中的细胞凋亡;同时采用免疫组化、逆转录-聚合酶链反应(RT-PCR)两种方法检测心肌炎小鼠不同时期心肌组织中Fas与FasL基因转录与蛋白的表达.结果光镜观察见对照组小鼠心肌组织无异常改变,实验组病鼠可见心肌细胞坏死和单核、淋巴细胞浸润,后期可见纤维化;电镜观察对照组心肌中未检出凋亡细胞,而病鼠心肌凋亡细胞检出率较高58.33%(7/12例),且细胞凋亡多存在于炎症病灶周围的心肌细胞及病灶处炎性浸润细胞;感染后第7～14天的病鼠心肌组织中,主要表达于心肌细胞的Fas mRNA及蛋白和主要表达于浸润淋巴细胞的FasL mRNA及蛋白均明显增强;FasL蛋白表达水平与心肌病变积分呈正相关(r=0.9082,P＜0.001).结论小鼠病毒性心肌炎中心肌损伤坏死与心肌细胞凋亡共存,通过Fas/FasL基因路径介导的心肌细胞凋亡与病毒性心肌炎的发病过程有关.     

黄芪三萜皂苷通过抑制CVB3诱导的心肌细胞凋亡保护病毒性心肌炎小鼠的心肌损伤

目的研究黄芪三萜皂苷(astragalus triterpenoid, AST)对病毒性心肌炎的保护作用。方法利用柯萨奇B3(CVB3)病毒构建病毒性心肌炎小鼠模型并使用AST进行干预,记录小鼠的死亡和体重变化情况、检测小鼠外周血中心肌损伤标志物乳酸脱氢酶(LDH)及肌酸激酶同工酶(CK-MB)水平、体外超声和心肌组织天狼星红染色评价小鼠的心脏功能及纤维化水平。TUNEL染色检测小鼠心肌组织凋亡水平,Westerm Blot检测小鼠心肌组织中凋亡相关因子caspase-3, Bax和Bcl-2的表达水平,初步探讨AST保护病毒性心肌炎的机制。结果 AST对CVB3诱导的小鼠死亡和体重减轻具有显著的保护作用;AST对CVB3诱导的心肌损伤具有显著的保护作用,主要表现为AST干预组小鼠外周血中LDH及CK-MB水平、心肌组织纤维化水平及心肌细胞凋亡水平较CVB3组小鼠显著降低;AST干预对CVB3诱导的小鼠心脏射血分数(EF)的降低和E/E'的升高具有显著地抑制作用,说明AST对CVB3诱导的小鼠心脏收缩和舒张功能的降低具有保护作用;CVB3诱导组小鼠心肌组织中凋亡相关因子Caspase-3, Bax, Bcl-2的表达水平及Bax/BCL-2比值较对照组小鼠显著增加,而AST干预组小鼠心肌组织中上述指标较CVB3组小鼠显著降低。结论 AST对CVB3诱导的病毒性心肌炎具有显著的保护作用,这种保护作用可能与其抑制CVB3诱导的心肌细胞凋亡有关。     

曲美他嗪对病毒性心肌炎小鼠的保护作用及其机制

目的:观察曲美他嗪对M株柯萨奇病毒B3(CVB3m)感染的病毒性心肌炎小鼠的保护作用并探讨其可能作用机制。方法:以CVB3m诱导的病毒性心肌炎Balb/c小鼠模型为研究对象。201只清洁级近交系4～6周龄雄性Balb/c小鼠随机分成5组。正常对照小鼠20只(正常组);病毒性心肌炎小鼠55只(心肌炎组);喂养曲美他嗪10 mg/(kg.d)的正常小鼠20只(药物对照组);喂养曲美他嗪10 mg/(kg.d)的病毒性心肌炎小鼠53只(低剂量治疗组);喂养曲美他嗪20 mg/(kg.d)的病毒性心肌炎小鼠53只(高剂量治疗组)。观察各组血清中肌钙蛋白I(cTnI)水平、血清中超氧化物歧化酶(SOD)、丙二醛(MDA)含量的变化以及心肌组织中Fas mRNA表达水平的变化。结果:小鼠感染CVB3m后第7天及第14天,与正常组及药物对照组比较,心肌炎组、低剂量治疗组和高剂量治疗组血清cTnI水平、MDA含量显著升高,SOD含量显著降低,Fas mRNA的表达显著增加,差异有统计学意义(P<0.05)。小鼠感染CVB3m后第7天,与心肌炎组比较,低剂量治疗组和高剂量治疗组血清cTnI水平显著降低,MDA含量显著降低,差异有统计学意义(P<0.05),与心肌炎组及低剂量组比较,高剂量治疗组SOD含量显著升高,Fas mRNA的表达显著减少,差异有统计学意义(P<0.05)。感染CVB3m后第14天,与心肌炎组比较,低剂量治疗组和高剂量治疗组血清cTnI水平、MDA含量显著降低,SOD含量显著升高,Fas mRNA的表达显著减少,差异有统计学意义(P<0.05),与低剂量治疗组比较,高剂量治疗组上述指标变化更明显,差异有统计学意义(P<0.05)。结论:曲美他嗪能够减少病毒性心肌炎中心肌细胞的损害。其机制可能与其抗氧化作用以及通过下调Fas mRNA水平抑制心肌细胞凋亡有关。     

穿孔素在慢性心肌损伤中的表达及其意义

目的：探讨穿孔素在阿萨奇病毒B组3型（CVB3m)至T－2毒素染毒小鼠心肌损伤中的表达及其意义,方法：实验组BALB／C小鼠1．0mg/kg体重T－2毒素隔日灌胃,3周后腹腔接种0．1ml内含1000TCID50的CVB3m病毒液,对照组生理盐水灌胃,腹腔接种0．1ml 1640营养液,观察心肌病理改变,同时用RTPCR技术对心肌组织中CVB3m RNA和穿孔素mRNA表达进行检测,结果：CVB3m感染T－2毒素染毒小鼠心肌出现慢性损伤,可见纤维结缔组织增生和坏死灶癜痕修复。心肌组织中持续表达CVB34m RNA和穿孔素mRNA。结论CVB3m RNA和穿孔素mRNA的持续表达可能是CVB3m致T－2毒素染毒小鼠心肌慢性损伤的机制之一。     

Calpastatin减轻病毒性心肌炎心脏炎症损伤的作用

目的探讨钙蛋白酶抑制蛋白(calpastatin)对柯萨奇B组病毒3型(coxsackievirus B3, CVB3)诱导的病毒性心肌炎小鼠心脏炎症损伤的作用。方法取全身过表达calpastatin的转基因小鼠(Tg-CAST)及野生型小鼠(WT)腹腔注射CVB3,感染病毒7 d后建立病毒性心肌炎模型。分为对照组、Tg-CAST组、WT病毒性心肌炎组、Tg-CAST病毒性心肌炎组。留取小鼠心肌、血清及脾脏组织标本,分别行组织病理学检查以及炎症损伤相关因子检测。结果①WT病毒性心肌炎小鼠心肌组织中炎症浸润面积、病毒包膜蛋白VP-I及血清cTnI水平均明显高于对照组(P0.001)。与WT病毒性心肌炎小鼠相比,Tg-CAST病毒性心肌炎小鼠心肌炎症浸润面积、VP-1及cTnl水平均明显降低(P0.05)。②WT病毒性心肌炎小鼠心肌、脾脏与血清中炎症因子HMGB1、TNF-α、IL-17水平及心肌β-NF-κB表达显著升高(P0.01),而Tg-CAST病毒性心肌炎小鼠相应指标均明显低于WT病毒性心肌炎小鼠(P0.05)。结论 calpastatin可能通过抑制NF-KB通路活化降低病毒性心肌炎小鼠HMGB1、TNF-α、IL-17水平,进而改善心脏炎症损伤。     

柯萨奇B3m病毒致小鼠急性心肌损伤的双向凝胶电泳分析

目的建立双向凝胶电泳体系分析柯萨奇B3m病毒(CVB3m)致小鼠急性心肌损伤过程中的蛋白质组差异,探讨CVB3m致心肌损伤的机制。方法分别提取感染CVB3m第0,4,8及21天的BALB/C鼠心肌组织总蛋白,采取固相pH梯度双向凝胶电泳技术分离总蛋白,用Image Master软件进行图像分析。结果心肌组织总蛋白平均抽提浓度为13.9 g/L;获得正常小鼠和急性CVB3m感染鼠不同感染时期(第4,8和21天)心肌组织双向电泳凝胶图谱,图像分析4块胶平均蛋白点数为(792±32)个,匹配率为61.25%±6.25%。随机选定不同感染时期的8个差异表达的蛋白质点,得到了表观相对分子质量和表观等电点等一系列数据。结论获得了CVB3m致小鼠急性心肌损伤的双向凝胶电泳图谱,建立了该模型的蛋白质双向凝胶电泳数据库,有利于该病毒引起小鼠心肌损伤机制的进一步研究。     

黄芪三萜皂苷通过抑制TGF-β1/Smad2、p38MAPK信号抑制CVB3诱导的心肌纤维化

目的本文旨在研究黄芪三萜皂苷(astragalus saponins,AST)对CVB3诱导心肌纤维化的保护作用及机制。方法使用CVB3病毒和BALB/c小鼠制备病毒性心肌炎模型并使用AST进行干预。记录不同处理组小鼠的生存曲线、检测不同干预组小鼠外周血中CK-MB水平、心肌组织HE染色和天狼星红染色检测心肌损伤和纤维化水平及通过western blot和qPCR检测心肌组织中TGF-β1、Smad2及p38MAPK水平以研究AST的作用机制。结果 AST能够显著提高小鼠的生存率,显著降低CVB3诱导的心肌损伤和外周血中CK-MB水平。与CVB3组小鼠比较,AST干预组小鼠心肌组织纤维化面积显著减少。无论是RNA水平还是蛋白水平,CVB3能够显著诱导TGF-β1、Smad2及p38MAPK在心肌组织中的表达,而AST对此具有显著地抑制作用。结论 AST对CVB3诱导的心肌组织纤维化具有显著地抑制作用,这种保护作用与抑制CVB3诱导的TGF-β1/Smad2、p38MAPK信号在心肌组织中的活化有关。     

TIMP-1 mRNA表达在病毒性心肌炎小鼠心肌胶原重构中的作用及其与TGF-β1的关系

目的探讨TIMP-1mRNA表达在病毒性心肌炎小鼠心肌胶原重构中的作用及其与转化生长因子(TGF-β1)的关系。方法4周龄雄性BALB/c鼠腹腔接种0.1ml100TCID50CVB3m,周龄、性别相同小鼠为对照,分别于接种后3、7、9、14、21、28、56d断脊处死小鼠,心肌标本经常规制片,VG染色观察心肌组织胶原的改变,原位杂交观察TIMP-1mRNA和TGF-β1mRNA的表达,免疫组织化学观察TGF-β1的表达。结果感染后28d小鼠心肌组织血管周围胶原明显沉积,感染后56d心肌组织血管周围及心肌细胞间隙胶原沉积均明显增加;感染后7d可见TIMP-1mRNA表达,14～21d最为明显,此后减弱,直到56d。感染后3d可见TGF-β1mRNA及TGF-β1表达,7～21d最为明显,此后减弱,持续至感染后56d;TIMP-1mRNA和TGF-β1表达等级间存在正相关关系(P<0.001)。结论TGF-β1表达增加及其上调TIMP-1mRNA的表达可能在病毒性心肌炎心肌胶原重构中起重要作用。     

妊娠时间与肺结核复发的相关性研究及诊治对策

目的 分析肺结核史患者妊娠时间和肺结核复发间相关性.方法 选取我院收治的有肺结核史的妊娠妇女576例作为研究对象,对其妊娠前肺结核治疗、治愈后妊娠时间、妊娠后复发肺结核等进行分析,总结有肺结核史育龄女性的妊娠时间和肺结核复发之间的关系.结果 肺结核治愈后不同时间段妊娠者的结核复发率比较,差异具有显著性（P＜0.05）,停药后间隔时间越久妊娠,肺结核复发的几率越小.结论 加强孕期痰菌检查,及早发现复发肺结核,提高母婴安全.     

我国骨关节结核诊治的回顾与展望

骨关节结核是危害人们健康的严重感染性疾病,近95％由他处结核病继发而来.罹患骨关节结核疾病后几乎均将致残,严重影响人们的健康、工作和生活.建国以来在党和国家的关心和支持下,骨关节结核的诊治水平取得了长足进步.时至今日,由于多种原因,学科发展和被重视程度受到一定的制约,同整个医疗行业的发展不相适应.回顾过去,展望未来,我们需要重新审视骨关节结核的诊治方法,努力推进骨关节结核诊疗技术的科学发展.     

Effect of phosphorylation of MAPK and Stat3 and expression of c-fos and c-jun proteins on hepatocarcinogenesis and their clinical significance

AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto detect the expression of p42/44~(MAPK), p-Stat3,c-fos and c-jun proteins in 55 hepatocellularcarcinomas (HCC) and their surrounding livertissues.RESULTS The positive rates and expressionlevels of p42/44~(MAPK), p-Stat3, c-fos and c-junproteins in HCCs were significantly higher thanthose in pericarcinomatous liver tissues (PCLT).A positive correlation was observed between theexpression of p42/44~(MAPK) and c-fos proteins, andbetween p-Stat3 and c-jun, but there was nosignificant correlation between P42/44~(MAPK) and p-Stat3 in HCCs and their surrounding livertissues.CONCLUSION The abnormalities of Ras/Raf/MAPK and JAKs/ Stat3 cascade reaction maycontribute to malignant transformation ofhepatocytes. Hepatocytes which are positive forp42/ 44~(MAPK), c-fos or c-jun proteins may bepotential malignant pre-cancerous cells.Activation of MAPK and Stat3 proteins may be anearly event in hepatocellular carcinogenesis.     

Overweight and Obesity and Progression of ADPKD

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Replication and Inhibitors of Enteroviruses and Parechoviruses

The Enterovirus (EV) and Parechovirus genera of the picornavirus family include many important human pathogens, including poliovirus, rhinovirus, EV-A71, EV-D68, and human parechoviruses (HPeV). They cause a wide variety of diseases, ranging from a simple common cold to life-threatening diseases such as encephalitis and myocarditis. At the moment, no antiviral therapy is available against these viruses and it is not feasible to develop vaccines against all EVs and HPeVs due to the great number of serotypes. Therefore, a lot of effort is being invested in the development of antiviral drugs. Both viral proteins and host proteins essential for virus replication can be used as targets for virus inhibitors. As such, a good understanding of the complex process of virus replication is pivotal in the design of antiviral strategies goes hand in hand with a good understanding of the complex process of virus replication. In this review, we will give an overview of the current state of knowledge of EV and HPeV replication and how this can be inhibited by small-molecule inhibitors.     

Effect of phosphorylation of MAPK and Stat3 and expression of c-fas and c-jun proteins on hepatocarcinogenesis and their clinical significance

AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto detect the expression of p42/44MAPK, p-Stat3,c-fos and c-jun proteins in 55 hepatocellularcarcinomas (HCC) and their surrounding livertissues.RESULTS The positive rates and expressionlevels of p42/44MAPK, p-Stat3, c-fos and c-junproteins in HCCs were significantly higher thanthose in pericarcinomatous liver tissues (PCLT).A positive correlation was observed between theexpression of p42/44MAPK and c-fos proteins, andbetween p-Stat3 and c-jun, but there was nosignificant correlation between p42/44MAPK and p-Stat3 in HCCs and their surrounding livertissues.CONCLUSION The abnormalities of Ras/Rat/MAPK and JAKs/ Stat3 cascade reaction maycontribute to malignant transformation ofhepatocytes. Hepatocytes which are positive forp42/ 44MAPK, c-fos or c-jun proteins may bepotential malignant pre-cancerous cells.Activation of MAPK and Stat3 proteins may be anearly event in hepatocellular carcinogenesis.     

心电图、心电向量图与冠状动脉造影结果对比分析

目的:通过分析心电图(Electrocardiogram,ECG)和心电向量图(Vectorcardiogram,VCG)的改变与冠脉造影（CAG）结果进行对比,探讨ECG、VCG在冠状动脉病变中的诊断价值。方法: 选择2008年1月~2009年12月临床拟诊断为冠心病患者108例,行常规ECG、VCG检查,并于1周内进行CAG,对检查结果依据各自的诊断标准进行判定,以CAG为标准诊断法,利用四格表法,计算相关评价真实性的指标并进行比较。结果: ①VCG检测的灵敏度、特异度、准确度显著高于ECG(P<0.05,P<0．01)。②ECG、VCG阳性率与冠脉病变支数组间比较:在单支病变、双支病变中,VCG阳性率明显高于ECG(P<0.05),左主干或三支病变无统计学意义;组内比较:ECG组左主干或三支病变组较单支病变、双支病变阳性率高(P<0.05,P<0.01);VCG组左主干或三支病变组较单支病变阳性率高(P<0.05);与双支病变阳性率比较无统计学意义;③ECG、VCG阳性率与冠脉病变程度组间比较:冠脉病变狭窄50%～69%的VCG阳性率明显高于ECG (P<0.05),其他两组阳性率比较无统计学意义;组内比较:ECG组冠脉病变狭窄≥90%较50%～69%、70%～89%的阳性率高(P<0.05,P<0.01); VCG组狭窄≥90%较50%～69%阳性率高（P<0.01),其他无统计学意义。结论: VCG对冠心病检测价值显著高于ECG。     

Detection and characterization of the product of hydroethidine and intracellular superoxide by HPLC and limitations of fluorescence

Here we report the structural characterization of the product formed from the reaction between hydroethidine (HE) and superoxide (O(2)(.-)). By using mass spectral and NMR techniques, the chemical structure of this product was determined as 2-hydroxyethidium (2-OH-E(+)). By using an authentic standard, we developed an HPLC approach to detect and quantitate the reaction product of HE and O(2)(.-) formed in bovine aortic endothelial cells after treatment with menadione or antimycin A to induce intracellular reactive oxygen species. Concomitantly, we used a spin trap, 5-tert-butoxycarbonyl-5-methyl-1-pyrroline N-oxide (BMPO), to detect and identify the structure of reactive oxygen species formed. BMPO trapped the O(2)(.-) that formed extracellularly and was detected as the BMPO-OH adduct during use of the EPR technique. BMPO, being cell-permeable, inhibited the intracellular formation of 2-OH-E(+). However, the intracellular BMPO spin adduct was not detected. The definitive characterization of the reaction product of O(2)(.-) with HE described here forms the basis of an unambiguous assay for intracellular detection and quantitation of O(2)(.-). Analysis of the fluorescence characteristics of ethidium (E(+)) and 2-OH-E(+) strongly suggests that the currently available fluorescence methodology is not suitable for quantitating intracellular O(2)(.-). We conclude that the HPLC/fluorescence assay using HE as a probe is more suitable [corrected] for detecting intracellular O(2)(.-).     

Effects of sex and time of day on metabolism and excretion of corticosterone in urine and feces of mice

Non-invasive techniques to monitor stress hormones in small animals like mice offer several advantages and are highly demanded in laboratory as well as in field research. Since knowledge about the species-specific metabolism and excretion of glucocorticoids is essential to develop such a technique, we conducted radiometabolism studies in mice (Mus musculus f. domesticus, strain C57BL/6J). Each mouse was injected intraperitoneally with 740 kBq of 3H-labelled corticosterone and all voided urine and fecal samples were collected for five days. In a first experiment 16 animals (eight of each sex) received the injection at 9 a.m., while eight mice (four of each sex) were injected at 9 p.m. in a second experiment. In both experiments radioactive metabolites were recovered predominantly in the feces, although males excreted significantly higher proportions via the feces (about 73%) than females (about 53%). Peak radioactivity in the urine was detected within about 2h after injection, while in the feces peak concentrations were observed later (depending on the time of injection: about 10h postinjection in experiment 1 and about 4h postinjection in experiment 2, thus proving an effect of the time of day). The number and relative abundance of fecal [3H]corticosterone metabolites was determined by high performance liquid chromatography (HPLC). The HPLC separations revealed that corticosterone was extensively metabolized mainly to more polar substances. Regarding the types of metabolites formed, significant differences were found between males and females, but not between the experiments. Additionally, the immunoreactivity of these metabolites was assessed by screening the HPLC fractions with four enzyme immunoassays (EIA). However, only a newly established EIA for 5alpha-pregnane-3beta,11beta,21-triol-20-one (measuring corticosterone metabolites with a 5alpha-3beta,11beta-diol structure) detected several peaks of radioactive metabolites with high intensity in both sexes, while the other EIAs showed only minor immunoreactivity. Thus, our study for the first time provides substantial information about metabolism and excretion of corticosterone in urine and feces of mice and is the first demonstrating a significant impact of the animals' sex and the time of day. Based on these data it should be possible to monitor adrenocortical activity non-invasively in this species by measuring fecal corticosterone metabolites with the newly developed EIA. Since mice are extensively used in research world-wide, this could open new perspectives in various fields from ecology to behavioral endocrinology.     

大鼠骨髓间充质干细胞的分离培养和外源基因的导入

目的探讨绿色荧光蛋白基因转染骨髓间质干细胞的可行性。方法采用F icoll-PaqueTMP lus淋巴细胞分离液,根据细胞密度梯度原理,分离大鼠骨髓间充质干细胞(rM SC s)并进行体外原代培养和传代扩增,倒置相差显微镜观察细胞生长情况,免疫细胞化学法对其初步鉴定。流式细胞仪分析转染效率。结果原代和传代培养的细胞呈现梭形外观,具有较强的生长增殖能力;细胞均一表达CD44、CD54、CD106、CD29抗原。电穿孔法转染rM SC s转染率为32.8%±3%。结论采用比重为1.077 g/L的F icoll-PaqueTMP lus能分离获得大鼠骨髓间充质干细胞,经原代培养和传代培养能够迅速扩增。电穿孔法具有较高的介导外源基因表达于rM SC s的效率。