后退式旋切导管治疗冠状动脉阻塞性病变的初步报告

目的评价后退式旋切导管(PAC)治疗冠状动脉病变的有效性和安全性.方法 55例冠状动脉病变选用PAC导管治疗,其中17例为支架内再狭窄病变,应用定量冠状动脉造影评价即刻和近期疗效.结果 55例患者手术成功率为95%,PAC导管使血管最小管腔直径从(1.07±0.51)mm 增加至(1.98±0.39) mm,并发症包括血管内膜撕裂7例,完全闭塞1例,6个月随访造影最小管腔直径为(1.97±0.67)mm,造影再狭窄率为27%.首次介入治疗病变与支架内再狭窄病变即刻与近期疗效相同,向心性病变较偏心性病变有更好的即刻效果.结论 PAC旋切导管能安全有效去除冠状动脉内粥样斑块,具有较高的即刻和近期有效率.     

后退式旋切导管对冠状动脉支架内再狭窄的治疗

目的 :评价后退式旋切导管 (PAC)治疗冠状动脉支架内再狭窄病变的有效性和安全性以及其即刻和近期定量冠状动脉造影结果。方法 :17例支架内再狭窄病变采用PAC治疗 ,应用定量冠状动脉造影评价即刻和近期疗效 ,并与同期的 38例首次介入治疗病变进行比较。结果 :支架内再狭窄组与首次介入治疗组相比PAC器械成功率分别为 10 0 %∶92 %、即刻造影残余狭窄率为 (36± 10 ) %∶(35± 15 ) %、斑块组织获取率为 94 %∶94 % ,两组差异无显著性意义 (P >0 .0 5 )。PAC所产生的血管腔直径增益为 (0 .78± 0 .6 6 )mm ,略低于首次介入治疗者〔(0 .97± 0 .5 5 )mm〕。PAC造成的主要并发症包括原置入支架带出 2例 ,血管内膜撕裂 3例。 6个月随访造影血管腔直径丢失指数为 0 .4 6± 0 .4 5 ,略低于首次介入治疗组 (0 .5 7± 1.13)。造影再狭窄率为 2 9% ,与首次介入治疗组相近 (2 6 % )。结论 :PAC能有效地用于冠状动脉支架内再狭窄病变的处理 ,具有较理想的即刻和近期有效率。     

药物涂层球囊在糖尿病患者冠状动脉小血管病变中的疗效分析

目的:观察药物涂层球囊(DCB)在糖尿病(DM)患者冠状动脉小血管病变应用中的有效性及近期疗效。方法:入选DM冠状动脉小血管病变患者39例,均单独应用DCB治疗,记录治疗前后最小管腔直径(MLD)、手术即刻成功率及主要不良心血管事件(MACE)发生率。6个月后复查冠状动脉造影,观察靶血管MLD,计算晚期管腔丢失(LLL)。结果:39例患者共46处病变接受DCB治疗,DCB扩张后,1处病变管壁急性弹性回缩,2处病变出现C型夹层,给予补救性置入药物洗脱支架(DES),手术即刻成功率93.48%,术后即刻MLD较术前显著增加(1.64±0.38)mm对(0.92±0.43)mm,P0.01,所有患者随访期间无死亡、心肌梗死事件发生。术后6个月28例患者复查冠状动脉造影,2例发生较明显的再狭窄,其中1例置入DES,1例再次给予DCB扩张治疗,复查造影患者的MLD为(1.46±0.32)mm,LLL为(0.18±0.31)mm。按靶血管部位分别计算,6个月后与术后即刻MLD比较,差异无统计学意义;按总体靶血管计算,差异有统计学意义(P0.05)。结论:DCB可显著增加DM患者冠状动脉小血管病变管腔直径,LLL较少,且耐受性好,无异物置入,即刻及短期疗效肯定。     

冠状动脉内放射治疗对支架内再狭窄的作用

目的　研究应用β射线 (90 Sr/90 y)进行冠状动脉内放射治疗对国人支架内再狭窄的作用。方法　自 1 999年 1 2月至 2 0 0 2年 1月 ,我院对 5 3例患者 [男 4 9例 ,女 4例 ,平均年龄 (5 3 2± 9 8)岁 ]5 5处支架内再狭窄病变 (支架直径≥ 2 5mm ,1 0mm≤病变长度≤ 30mm) ,在球囊 (1 0处病变用普通球囊 ,4 5处病变用切割球囊 )满意扩张后 ,应用Beta Cath系统 (Novoste)进行冠状动脉内放射治疗。放射源长度 4 0mm。术后 8个月随访冠状动脉造影 ,用MEDCONViewer软件包进行定量冠状动脉造影 (QCA)分析。结果　 5 3例患者 5 5处支架内再狭窄病变均被满意扩张 ,冠状动脉内放射治疗全部成功 ,术中并发冠状动脉痉挛 1例 (1 8%) ,无其他并发症。全部患者随访期中无死亡 ,随访≥ 8个月 33例患者中 1例 (3 0 %)发生非Q波心肌梗死 ,6例 (1 8 2 %)进行靶血管重建术。该 33例患者中 2 9例(87 9%) 30处病变进行了随访冠状动脉造影 ,再狭窄率在支架段为 1 0 0 %(3/30 ) ,分析段为 2 3 3 %(7/30 )。最小管径直径术前为 (0 41± 0 2 2 )mm ,术后即刻为 (1 99± 0 42 )mm ,8个月随访时为 (1 73± 0 82 )mm ,平均病变长度为 (2 3 3± 5 4)mm。全部患者无晚期血栓形成、假性动脉瘤及冠状动脉瘤发生。结论　应用90 Sr     

小血管支架的临床应用

目的　评价具有磷酸胆碱涂层的小血管支架治疗细小冠状动脉病变 (≤ 3 0mm)的疗效。方法　选择 4 5例冠心病患者 ,男 35例 ,女 10例 ,年龄 (5 4 2± 10 5 )岁。常规行冠状动脉造影 ,以美国GE公司研制的血管造影机 (GEAdvantx)测量系统实时测量病变血管直径。小于 3 0mm的病变血管共 5 4支 ,平均血管直径为 (2 0± 0 4 5 )mm ,植入PC涂层 (BiodivYsioSV)支架 5 9个。结果　 5 4支病变血管均经球囊扩张后植入支架 ,手术成功率为 10 0 %。支架植入后平均狭窄直径减至 0 %～10 %,无一例急性或亚急性支架内血栓形成。全部病例随访 (6± 2 4 )个月 ,无一例死亡。 10例于术后(4± 1 2 )个月出现心绞痛复发 ,经冠状动脉造影证实 8例为支架内再狭窄 ,2例出现其他部位血管病变。结论　应用具有磷酸胆碱涂层的支架治疗小血管病变 ,再狭窄率低 ,临床疗效肯定。     

不稳定型心绞痛无保护左主干病变支架术后随访研究

目的　探讨冠状动脉内支架治疗无保护左主干病变 (LMD)的安全性及有效性。方法　2 7例LMD经球囊预扩张后置入支架。术后 6和 12个月行冠状动脉造影随访。结果　左主干开口病变 12例、体部 4例、末端 6例 (累及分叉开口 6例、单纯末端 1例 ) ,自开口到体部均狭窄者 5例 (含自开口处就完全闭塞 1例 )。术后 12个月时 ,左心室射血分数从 4 9 8%增加到 5 6 3% (P <0 0 5 )。球囊扩张时 2 0例 ( 6 2 % )出现显著心率减慢和血压下降。共置入 2 8枚支架 ,其中左主干内 2 7枚 ,主干内支架直径 ( 3 90± 0 4 7)mm、长度 ( 12 5 4± 3 95 )mm。全部患者均完成 12个月的临床随访 ,19例 ( 70 % )患者接受 6个月时冠状动脉造影 ,3例支架内再狭窄 ( 15 % ) ,其中 2例接受冠状动脉旁路术 ,1例行血管内放射治疗 ;术后 12个月时 15例 ( 5 5 % )行冠状动脉造影随访 ,1例再狭窄行冠状动脉旁路术 ,因此术后 12个月内累积再狭窄率为 2 1%。 4例再狭窄患者中 ,3例为末端病变 ( 75 % ) ,1例为开口病变( 2 5 % )。结论　冠状动脉内支架治疗LMD疗效可靠 ,冠状动脉造影随访可及时发现再狭窄。左主干末端病变再狭窄率显著。     

联合应用切割球囊与放射治疗对冠脉支架内再狭窄的作用

目的 :探讨联合应用切割球囊及β射线 （1 66Ho）冠脉内放射治疗对支架内再狭窄的作用。方法 :对 2 0 0 1- 0 1～2 0 0 2 - 0 3韩国亚洲大学医院心脏中心完成的 6 0例支架内再狭窄的患者 ,全部使用切割球囊预扩张 ,满意扩张后使用充满液态 1 66Ho的长球囊 （30～ 40 mm ）进行冠脉内放射治疗。术后随访主要临床不良事件 ,并于术后 8个月行冠状动脉造影 ,用 MEDCON Viewer软件包进行定量冠状动脉造影 （QCA）分析。结果 :6 0例患者 6 5处支架内再狭窄病变均被满意扩张 ,血管内放射治疗全部成功 ,无撕裂、血栓形成等并发症。随访 8个月 ,无 1例死亡。 5例 （8.3%）于术后 3个月出现心绞痛行靶病变血管重建术 ,其余 5 5例患者均于术后 8个月行冠状动脉造影 ,4例于支架内发生再狭窄 （7.3%） ,6例于支架边缘发生再狭窄 （10 .9%） ,全部患者无晚期血栓形成、假性动脉瘤及冠状动脉瘤发生。病变长度为 2 5 .1± 4.7mm。晚期管腔丧失为 0 .19± 0 .6 8mm。最小管腔直径术前为 0 .38± 0 .2 6 mm ,术后即刻为 2 .0 8± 0 .36 m m ,8个月随访时为 1.82± 0 .76 mm。结论 :联合应用切割球囊及β射线 （1 66Ho）冠脉内放射治疗对支架内再狭窄是有效及安全的 ,可在临床推广应用。     

PC支架治疗小直径冠脉病变3年随访研究

目的　评价PC支架治疗小直径冠状动脉血管病变的手术成功率、术后主要临床不良事件发生情况及远期再狭窄率。方法　观察我院 1998年 4月至 2 0 0 1年 5月 4 5例小血管 (血管直径 <2 8mm)患者冠心病患者植入PC支架的手术成功率、主要临床不良事件发生情况及远期再狭窄率。随访 1个月至 3年 ,其中 2 8例行冠状动脉造影术复查。结果　手术成功率 10 0 % ,支架全部顺利置入。血管狭窄率由 (82± 10 ) %改善至术后的 (0± 5 ) % (直径法 )。术后 30d随访 ,1例支架内 5 0 %狭窄。 1例术后第 2 2天因急性左心衰死亡。术后 6个月随访 38例。 1例支架完全闭塞 ,1例原支架内及近远端多发性狭窄 ,考虑合并其他血管病变 ,给予搭桥术。 35例随访时间 3年。完全无症状 2 6例。 2例随访过程中支架内狭窄 ,1例术后第 2年因心血管事件死亡。术后第 3年 ,有 2 8例在行冠脉造影复查 ,PC支架植入的 30处 ,6处发生支架内再狭窄 (狭窄 >5 0 % ) ,2例出现支架近端狭窄。冠脉造影再狭窄率为 2 6 6 7% ,总再狭窄率为 2 5 5 %。结论　小血管PC支架术手术成功率高 ,术后即刻效果好 ,术后远期生存率较高 ,再狭窄率接近大血管 >3 0mm普通裸支架     

经皮切割球囊成形术治疗支架内再狭窄的研究

目的　研究切割球囊成形术对治疗支架内再狭窄的即刻和 6个月内随访效果。方法　 6 9例支架内再狭窄患者随机分配到切割球囊组 (38例 )和普通球囊治疗组 (31例 )。球囊扩张前及扩张后即刻在定量冠状动脉造影和冠状动脉内超声下 ,测定相关参数。观察随访 6个月内临床改善及冠状动脉造影结果。研究终点包括出现心肌梗死 ,需要冠状动脉搭桥或再介入治疗。结果　两组的手术成功率均为 10 0 %。切割球囊组 1例患者扩张后在支架的远端出现夹层。平均随访 (6 .7± 2 .3)个月。切割球囊组于术后 3和 6个月时的再狭窄率显著低于普通球囊组(15 %∶38%及 18%∶4 2 % ,P <0 .0 0 1)。扩张后即刻血管直径获得值在切割球囊组和普通球囊组分别为 (1.72±0 .5 2 )mm和 (1.15± 0 .5 4 )mm ,随访 3个月及随访终点时切割球囊组的血管直径晚期丢失分别为 (0 .2 6± 0 .0 5 )mm(3个月 )及 (0 .38± 0 .0 6 )mm ,同时的普通球囊组丢失值分别为 (0 .78± 0 .19)mm(3个月 )及 (0 .89± 0 .16 )mm。结论　切割球囊成形术治疗老年冠心病患者支架内狭窄效果可靠 ,安全 ,容易操作 ,再狭窄率低     

药物涂层球囊在冠状动脉回旋支开口病变介入治疗中的临床应用

目的探讨药物涂层球囊应用于冠状动脉回旋支开口病变的可行性。方法选择2015年10月至2017年6月在首都医科大学附属北京朝阳医院心脏中心经冠状动脉造影证实冠状动脉回旋支开口病变的患者12例,Medina分型0,0,1;行经皮冠状动脉介入术(PCI),应用药物涂层球囊处理病变,术后即刻行冠状动脉造影检查。术后6个月临床随访和复查冠状动脉造影,统计患者主要不良心血管事件。结果 12例患者PCI成功率为100%,血管最小管腔直径由术前的(0.31±0.12)mm增加至术后的(2.86±0.43)mm(P0.001)。术后6个月内患者未发生主要不良心血管事件;10例患者复查冠状动脉造影,造影随访率83.3%,造影随访无再狭窄,管腔直径(2.93±0.39)mm。结论药物涂层球囊应用于冠状动脉回旋支开口病变安全、有效。     

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。