聚乳酸可吸收根管桩与3种粘接剂的粘接强度

目的:研究聚乳酸可吸收根管桩与3种粘接剂的粘接强度,寻找可用于聚乳酸可吸收根管桩的合适的可吸收粘接剂,为进一步的应用奠定基础. 方法:使用聚乳酸根管桩修复离体牙,用不同的粘接剂进行聚乳酸根管桩的粘接. 按使用的粘接剂分为3组:氰基丙烯酸酯粘接剂组、纤维蛋白粘接剂组和玻璃离子水门汀组. 将离体牙制成薄片试样并进行微推出试验,测试不同粘接剂的粘接强度,对结果进行方差分析. 将经过测试的薄片试样,放置于显微镜下观察粘接破坏的方式,分为4种:桩-粘接剂界面破坏、牙本质-粘接剂界面破坏、粘接剂的破坏和可吸收桩的破坏. 结果:测得氰基丙烯酸酯粘接剂的粘接强度为(16. 83 ± 6. 97) MPa,玻璃离子水门汀的粘接强度为(12. 10 ± 5. 09)MPa,这两组的粘接强度均高于纤维蛋白粘接剂的粘接强度(1. 17 ± 0. 50)MPa,P<0. 001,差异有统计学意义,而氰基丙烯酸酯粘接剂的粘接强度与玻璃离子水门汀的粘接强度的差异没有统计学意义,P值为0. 156.观察粘接破坏的方式,在氰基丙烯酸酯粘接剂组,桩-粘接剂界面破坏占25. 0%,牙本质-粘接剂界面破坏占16. 7%,粘接剂的破坏占33. 3%,可吸收桩的破坏占25. 0%;在纤维蛋白粘接剂组,桩-粘接剂界面破坏占66. 7%,牙本质-粘接剂界面破坏占22. 2%,粘接剂的破坏占11. 1%;在玻璃离子水门汀组,桩-粘接剂界面破坏占87. 5%,粘接剂的破坏占12. 5%. 纤维蛋白粘接剂和玻璃离子水门汀粘接剂,以桩-粘接剂界面破坏为主,而在氰基丙烯酸酯粘接剂组,各种破坏方式的出现次数较为平均. 结论:从粘接强度方面,纤维蛋白粘接剂的粘接强度低,难以满足临床使用的需求,氰基丙烯酸酯粘接剂和玻璃离子水门汀的粘接强度可以满足临床需求;氰基丙烯酸酯粘接剂是可用于聚乳酸可吸收根管桩的较好的可吸收粘接剂.     

不同温度新型大气压冷等离子体处理对牙本质粘接强度的影响

目的:研究不同温度条件下新型大气压冷等离子体(radio-frequency atmospheric-pressure glow discharge,RF-APGD)处理对牙本质粘接强度的影响。方法:(1)收集新鲜拔除的、无龋坏的、完整的第三磨牙52颗,采用精密低速切割机制备平行于牙合中层牙本质薄片,每颗离体牙制备1片 [(900±100) μm]。将52个中层牙本质薄片随机分为对照组和实验组,其中对照组4片,无处理;实验组48片,按新型RF-APGD等离子体不同处理温度(4 ℃、10 ℃、20 ℃、30 ℃)平均分为4组,每大组12片。每大组按照不同处理时间(10 s,20 s,30 s)平均分为3个小组,每小组4片。采用扫描电镜观察脱矿牙本质表面形貌。(2)收集20颗完整第三磨牙随机分为对照组和4个实验组,每组4颗。对照组,无处理;4 ℃、10 ℃、20 ℃和 30 ℃ 4个实验组,每组采用新型RF-APGD等离子体处理20 s。实验组及对照组采用低速水冷精密切割机垂直于牙长轴去除牙合面牙釉质,暴露中层牙本质;采用32%磷酸酸蚀剂对牙本质表面进行酸蚀;采用牙本质粘接剂和树脂进行牙本质-树脂粘接,采用万能力学机进行牙本质-树脂粘接试件即刻微拉伸强度测定,观察不同温度新型RF-APGD等离子体处理对牙本质-树脂即刻粘接性能的影响。结果:(1)扫描电镜观察脱矿牙本质表面形貌显示,30 ℃和20 ℃新型 RF-APGD 等离子体处理组,脱矿牙本质胶原纤维表面经新型RF-APGD等离子体处理10 s即会出现微结构的破坏;10 ℃新型RF-APGD等离子体处理脱矿牙本质表面 20 s,即会出现牙本质胶原纤维之间间隙变小、表面结构坍塌等现象;4 ℃新型RF-APGD等离子体处理10 s、20 s及30 s,脱矿牙本质表面胶原纤维网状结构均能维持蓬松结构。(2)牙本质-树脂即刻微拉伸强度结果显示,对照组为(47.4±0.5) MPa,4 ℃、10 ℃、20 ℃和30 ℃新型RF-APGD等离子体处理组分别为(57.8±0.7) MPa、(51.9±0.7) MPa、(29.7±1.0) MPa和(22.2±1.5) MPa,其中4 ℃新型RF-APGD等离子体处理组所获得的微拉伸强度最高,与其他各组相比,差异具有统计学意义(P<0.05), 4 ℃和10 ℃新型RF-APGD等离子体处理组和对照组相比,牙本质-树脂微拉伸粘接强度分别提高了21.9%和9.5%。结论:4 ℃新型RF-APGD等离子体对脱矿牙本质胶原纤维的处理,较更高温度的新型RF-APGD等离子体更有利于提高牙本质-树脂的即刻粘接性能。     

自黏性流动树脂的性能研究

目的:通过自黏性流动树脂与自酸蚀粘接剂以及传统型复合树脂的比较,研究了自黏性流动树脂的性能,并进一步明确酸蚀预处理对自黏性流动树脂与牙本质粘接性能以及自酸蚀粘接剂与牙本质粘接性能的影响。方法:对90颗牛牙进行牙体预备,暴露牙本质,随机平均分为3组(A组、B组、C组):A组为自黏性流动树脂与牙本质粘接、B组为自黏性流动树脂加自酸蚀粘接剂与牙本质粘接、C组为传统型复合树脂加自酸蚀粘接剂与牙本质粘接。根据是否行酸蚀预处理,进一步分为非酸蚀组(记为A1组、B1组、C1组)和酸蚀组(记为A2组、B2组、C2组)。测试粘接试样的剪切粘接强度,并对测试结果进行单因素方差(one-way ANOVA,LSD)分析。结果:A1组的粘接强度[(3.39±1.71)MPa]低于B1组的粘接强度[(21.58±4.50)MPa],且两组之间的差异有统计学意义(P<0.05);B1组的粘接强度和C1组的粘接强度[(19.31±6.79)MPa]之间的差异没有统计学意义(P>0.05)。酸蚀预处理后,A2组的粘接强度[(6.75±3.54)MPa]大于A1组,但酸蚀预处理导致自酸蚀粘接剂与牙本质的粘接强度降低,即B2组[(16.56±7.39)MPa]的粘接强度低于B1组,C2组[(11.31±5.54)MPa]的粘接强度低于C1组。结论:自黏性流动树脂与自酸蚀粘接剂一起使用时,与牙本质的粘接强度高于单独使用自黏性流动树脂。与自酸蚀粘接剂一起与牙本质粘接时,自黏性流动树脂与传统型复合树脂之间的差异没有统计学意义,但是,酸蚀预处理会降低自酸蚀粘接剂与牙本质的粘接强度,并使粘接强度结果的变异系数增大。     

热循环对二种粘接剂的树脂-牙本质界面粘接强度的影响

目的:评价在离体条件下热循环对树脂-牙本质界面粘接强度的影响。方法：选取60颗人无龋磨牙,在低速锯下去除冠部牙釉质,暴露出牙本质,用300目、600目的碳化硅砂纸依次抛光处理后,按热循环处理方法随机分成3组,各组内用全酸蚀粘接剂系统中的Single Bond和自酸蚀粘接剂系统中的Adper Prompt分别粘接处理10颗牙。第1组（n=20）,无热循环处理,试件在37℃的蒸馏水中保存24 h后取出进行剪切强度(shear bond strength)测试;第2组(n=20),试件热循环处理500次;第3组（n=20）,试件热循环处理1 000次。后两组的温度均设定为5℃~55℃,闭模时间为30 s,传递时间20 s。热循环机处理后的试件在37℃蒸馏水中保存24 h后取出进行剪切强度测试。3组均在Instron1121万能材料试验机上进行剪切强度测试,加载的速度为1 mm·min^-1。剪切强度测试结束后,每组选取Single Bond和Adper Prompt试件的断裂面各1例,进行扫描电子显微镜的观察。结果：热循环0、500及1 000次后的剪切强度（MPa）依次为(Single Bond)18.12±3.36、17.62±3.61及16.93±2.66;(Adper Prompt)13.22±2.76、12.93±2.93及11.17±2.63。不同的热循环处理组间的剪切强度差异均无显著性（P>0.05）;各组中Single Bond的剪切强度显著高于Adper Prompt(P<0.05);扫描电子显微镜显示,Single Bond试件断裂面内的树脂突多于Adper Prompt。结论:短期内,热循环对树脂-牙本质界面的剪切强度没有显著的影响;在本研究中所选用的全酸蚀粘接剂系统的粘接强度显著高于自酸蚀粘接剂系统的粘接强度。     

通用型粘接剂对双固化树脂水门汀牙本质粘接强度的影响

目的：研究一步法和两步法通用型粘接剂与不同双固化树脂水门汀匹配使用时,光固化模式对牙本质粘接强度的影响。方法： 选用一步法通用型粘接剂Single Bond Universal（SBU）和两步法通用型粘接剂OptiBond Versa（VSA）作为研究对象,以一步法自酸蚀粘接剂OptiBond All in One（AIO）和两步法自酸蚀粘接剂Clearfil SE Bond（SEB）作为对照,同时选择RelyX Ultimate（RLX）和Nexus 3 Universal（NX3）作为不同的双固化树脂水门汀。收集新鲜无龋磨牙80颗,切除冠部釉质,暴露牙本质平面。根据粘接剂种类、粘接剂是否进行光固化和水门汀种类的不同组合分为16组,每组随机5颗。按照说明使用各组粘接剂,光固化（10 s）或者不进行光固化后,在粘接剂上方放置树脂水门汀厚度为1 mm,光照20 s（650 mW/cm2）,然后在水门汀上方分层填压复合树脂并固化（厚度5 mm）。水中储存24 h后,使用慢速切片机制备横截面积1 mm×1 mm的条形树脂-水门汀-牙本质样本,测定微拉伸粘接强度。结果： SBU光固化后与RLX和NX3联合使用,粘接强度［(35.45±7.04) MPa和(26.84±10.39) MPa］显著高于未光固化组［(17.93±8.93) MPa和(10.07±5.89) MPa, P<0.001］。SBU在相同光固化模式下,与RLX匹配使用的粘接强度显著高于与NX3匹配使用的粘接强度(P<0.05)。与对照AIO相比,SBU光固化后与RLX匹配使用时的粘接强度高于AIO组［(35.45±7.04) MPa vs. (24.86±8.42) MPa, P<0.05］,而未光固化下SBU的粘接强度低于AIO组［(17.93±8.93) MPa vs. (22.28±7.57) MPa, P<0.05］。两步法通用型粘接剂VSA与对照粘接剂SEB在不同的光照模式及联合使用不同的水门汀各组之间的粘接强度（25.98~32.24 MPa）差异没有统计学意义（P>0.05）。结论： 一步法通用型粘接剂的固化模式以及双固化水门汀的种类对于水门汀与牙本质的粘接强度均有一定的程度的影响。对于两步法通用型粘接系统,固化模式以及水门汀的种类对于水门汀与牙本质的粘接强度无显著影响。     

改良式微推出试验评价化学处理玻璃纤维桩表面后与树脂水门汀的粘接强度

目的:建立一种改良式微推出方式测试玻璃纤维桩表面经35%磷酸+硅烷偶联剂处理后与树脂水门汀的粘接强度,探讨此种测试模式评价玻璃纤维桩与树脂水门汀粘接强度的价值。方法:先将40支玻璃纤维桩随机分成2大组,每组20支,组1为磷酸+硅烷化组,组2为对照组。再将每一大组随机分为M(改良)和T(传统)两个小组,每组10支,分别用改良式微推出试验和传统微推出试验测定纤维桩与树脂水门汀的粘接强度并观察破坏模式。结果:组1M(磷酸+硅烷化组-改良)微推出粘接强度为(18.85±1.42) MPa,组1T(磷酸+硅烷化组-传统)为(19.39±1.35) MPa,组2M(对照组-改良)为(11.26±1.57)MPa,组2T(对照组-传统)为(11.27±1.83)MPa,在改良组和传统组中,磷酸+硅烷化组粘接强度值均显著高于对照组(P<0.01),且改良组中断裂模式100%为桩/树脂界面破坏,相比传统组的65.7%,更加集中体现界面粘接强度的变化。结论:相较于传统组,改良组微推出试验能更有效地评价纤维桩与树脂水门汀之间的粘接强度,且35%磷酸+硅烷化处理玻璃纤维桩表面可以更有效地提高其与树脂水门汀的粘接强度。     

生物活性玻璃预处理对牙本质粘接界面耐久性的影响

目的:研究生物活性玻璃(bioactive glass, BG)预处理对维持牙本质粘接界面耐久性的作用。方法:选取30颗无龋坏第三磨牙,去除冠部釉质制备牙本质平面,随机均分对照组、BG组、三偏磷酸钠(sodium trimetaphosphate, STMP)-聚丙烯酸(polyacrylic acid, PAA)-BG组(S-P-BG组)。各组均使用35%(质量分数)磷酸酸蚀牙本质样本,BG组再使用0.5 g/L BG涂擦酸蚀后的牙本质样本;S-P-BG组先使用5%(质量分数)STMP、5%(质量分数)PAA浸泡酸蚀后的牙本质样本1 min,再使用0.5 g/L BG涂擦牙本质样本。各组样本使用3M Single Bond 2粘接剂及3M Z350XT复合树脂粘接,并制备微拉伸柱状样本,每颗牙的柱状样本按时间随机分为24 h、1个月、3个月组。各组样本保存在37 ℃人工唾液(artificial saliva, AS)中相应时间后,进行微拉伸粘接强度测试,并使用单因素方差分析及LSD法进行统计学分析,扫描电镜下观察粘接断裂界面形貌。另选取27颗无龋坏第三磨牙制备牙本质平面,随机分为对照组、BG组、S-P-BG组,并按上述分组处理牙本质样本,再使用含0.1%(质量分数)罗丹明B的3M Single Bond 2粘接剂完成粘接。去除样本牙根暴露髓腔,并保存在 37 ℃ AS中24 h、1个月、3个月后,髓腔内放置0.1(质量分数)荧光素钠溶液染色1 h,激光共聚焦显微镜观察粘接界面形态及混合层微渗漏。结果:AS中浸泡24 h、1个月后,3组微拉伸粘接强度间的差异无统计学意义(P>0.05);浸泡3个月后,S-P-BG组微拉伸粘接强度为(36.91±7.07) MPa,高于对照组粘接强度(32.73±8.06) MPa,且差异有统计学意义(P=0.026);对照组、BG组3个月的微拉伸粘接强度较24 h呈下降趋势,且差异有统计学意义(对照组P=0.017,BG组P=0.01);S-P-BG组3个月微拉伸粘接强度较24 h粘接强度[(37.99±7.98) MPa]下降,但差异无统计学意义(P>0.05)。扫描电镜观察24 h粘接断裂面,3组均未见明显矿化;1个月、3个月后,BG组、S-P-BG组的粘接界面可见矿物质形成,S-P-BG组无明显胶原暴露。激光共聚焦显微镜观察对照组、BG组与S-P-BG组树脂突形成的形态及数量无明显差异;3组样本粘接24 h后粘接界面混合层均有渗漏,3个月后对照组微渗漏增加,BG组和S-P-BG组混合层微渗漏减少。结论:BG预处理牙本质粘接界面能够在粘接界面形成矿物质,减少粘接混合层微渗漏;STMP、PAA 与BG共同预处理牙本质粘接界面,可能在一定程度上维持牙本质粘接修复的耐久性。     

生物活性玻璃预处理对牙本质粘接界面耐久性的影响

目的:研究生物活性玻璃(bioactive glass, BG)预处理对维持牙本质粘接界面耐久性的作用。方法:选取30颗无龋坏第三磨牙,去除冠部釉质制备牙本质平面,随机均分对照组、BG组、三偏磷酸钠(sodium trimetaphosphate, STMP)-聚丙烯酸(polyacrylic acid, PAA)-BG组(S-P-BG组)。各组均使用35%(质量分数)磷酸酸蚀牙本质样本,BG组再使用0.5 g/L BG涂擦酸蚀后的牙本质样本;S-P-BG组先使用5%(质量分数)STMP、5%(质量分数)PAA浸泡酸蚀后的牙本质样本1 min,再使用0.5 g/L BG涂擦牙本质样本。各组样本使用3M Single Bond 2粘接剂及3M Z350XT复合树脂粘接,并制备微拉伸柱状样本,每颗牙的柱状样本按时间随机分为24 h、1个月、3个月组。各组样本保存在37 ℃人工唾液(artificial saliva, AS)中相应时间后,进行微拉伸粘接强度测试,并使用单因素方差分析及LSD法进行统计学分析,扫描电镜下观察粘接断裂界面形貌。另选取27颗无龋坏第三磨牙制备牙本质平面,随机分为对照组、BG组、S-P-BG组,并按上述分组处理牙本质样本,再使用含0.1%(质量分数)罗丹明B的3M Single Bond 2粘接剂完成粘接。去除样本牙根暴露髓腔,并保存在 37 ℃ AS中24 h、1个月、3个月后,髓腔内放置0.1(质量分数)荧光素钠溶液染色1 h,激光共聚焦显微镜观察粘接界面形态及混合层微渗漏。结果:AS中浸泡24 h、1个月后,3组微拉伸粘接强度间的差异无统计学意义(P>0.05);浸泡3个月后,S-P-BG组微拉伸粘接强度为(36.91±7.07) MPa,高于对照组粘接强度(32.73±8.06) MPa,且差异有统计学意义(P=0.026);对照组、BG组3个月的微拉伸粘接强度较24 h呈下降趋势,且差异有统计学意义(对照组P=0.017,BG组P=0.01);S-P-BG组3个月微拉伸粘接强度较24 h粘接强度[(37.99±7.98) MPa]下降,但差异无统计学意义(P>0.05)。扫描电镜观察24 h粘接断裂面,3组均未见明显矿化;1个月、3个月后,BG组、S-P-BG组的粘接界面可见矿物质形成,S-P-BG组无明显胶原暴露。激光共聚焦显微镜观察对照组、BG组与S-P-BG组树脂突形成的形态及数量无明显差异;3组样本粘接24 h后粘接界面混合层均有渗漏,3个月后对照组微渗漏增加,BG组和S-P-BG组混合层微渗漏减少。结论:BG预处理牙本质粘接界面能够在粘接界面形成矿物质,减少粘接混合层微渗漏;STMP、PAA 与BG共同预处理牙本质粘接界面,可能在一定程度上维持牙本质粘接修复的耐久性。     

两种牙本质粘接剂的微拉伸强度测试研究

目的　探讨改良的微拉伸法在同一牙上做平行配对粘接比较的可行性 ,并评价两种新型牙本质粘接剂 (Prime & Bond RNT;Prime one Mirage TM)的粘接效果。方法　选用 15颗拔出的无龋人类磨牙 ,冠部横切暴露牙本质 ,于中央垂直向下开一深约 5 mm的小槽 ,将粘接面分成大致相等的两部分 ,以分别接受两种粘接剂处理。粘接后的标本浸于 37℃的蒸溜水中 2 4小时后分成两组 : 组 (5颗牙 )直接测试粘接强度 ; 组 (10颗牙 )则在粘接强度测试前行 5℃和 5 5℃的冷热循环 2 40 0次。各预备的标本被片切成若干“酒杯”形薄块 (凹槽间最窄处相距约为1.0 m m)供拉伸测试。结果　未经温度循环和经温度循环的两组试件的粘接强度分别为 :Prim e & Bond RNT:42 MPa、 31MPa;Prim e one Mirage TM:6 4MPa、38MPa。双因素方差分析表明 ,此两种粘接剂的微拉伸强度间以及它们各自是否行冷热循环处理的粘接强度间均存在显著性差异 (P<0 .0 0 1)。而配对多重比较 (t检验 )提示 ,经冷热循环后这两种粘接剂的微拉伸强度间差异无显著性 (P>0 .0 5 )。回归分析提示 ,以每牙为单位分别得出的这两种粘接剂各自的平均微拉伸强度间存在相关性 ,并具有统计学意义 (r=0 .5 75 ,P<0 .0 5 )。结论　改良微拉伸法可用于比较和评价两种牙本质粘接     

次氯酸钠溶液表面处理对牙本质粘接强度的影响

目的：研究根管治疗过程中次氯酸钠（sodium hypochlorite,NaOCl）冲洗溶液对牙本质粘接强度的影响。方法： 选取新鲜拔除的人第三磨牙15颗,牙冠完整无龋坏,未经牙体或牙髓治疗,去除釉质,暴露中层牙本质,600目砂纸打磨牙本质表面1 min,去离子水冲洗1 min,制备牙本质平面试件。试件随机分为3组,采用不同表面处理方法后制作粘接试件：A组（阴性对照组）,去离子水处理牙本质平面试件20 min;B组（2.50% NaOCl实验组）,2.50% NaOCl溶液处理牙本质平面试件20 min,每5分钟更换1次新鲜溶液;C组（5.25% NaOCl实验组）, 5.25% NaOCl溶液处理牙本质平面试件20 min,每5分钟更换1次新鲜溶液。处理后所有试件表面均使用自酸蚀粘接剂SE bond进行粘接处理,上方堆塑5 mm高的AP-X复合树脂,分层固化后,粘接试件置于37 ℃去离子水中储存24 h后,使用金刚石切割机垂直于粘接界面切割,制作1.0 mm×1.0 mm条状试样（n=45）。用微拉伸测试仪测试条状试样微拉伸粘接强度（MPa）, 体视显微镜下观察试样断裂类型（界面破坏、内聚破坏及混合破坏类型）,采用单因素方差分析比较不同实验组的微拉伸粘接强度,并用Post-hoc test（LSD）法进行两两比较,应用卡方检验比较不同组之间断裂类型分布的差异,并进行两两比较。结果： 2.50%NaOCl实验组［（26.04±5.74 ）MPa］和5.25%NaOCl实验组［（24.46±3.77） MPa］的粘接强度明显低于未经NaOCl溶液处理的阴性对照组［（48.71±7.77 ）MPa］,P=0.000。与阴性对照组比较,2.50%和5.25%NaOCl实验组粘接强度分别下降了46.5%和50.2%,2.50%和5.25%NaOCl实验组间粘接强度差异无统计学意义（P=0.214）。不同实验组之间断裂类型分布差异均具有统计学意义（χ2=56.324,P=0.000）, 阴性对照组试样断裂类型以混合破坏类型（68.9%）为主,界面破坏类型（24.4%）次之,内聚破坏类型（6.7%）最少,2.50%NaOCl实验组与5.25%NaOCl实验组发生界面破坏类型的比例明显高于阴性对照组(P=0.000),2.50%NaOCl实验组和5.25%NaOCl实验组间的断裂类型分布差异无统计学意义（P=0.197）,且均未发现内聚破坏。结论： NaOCl处理过的牙本质与复合树脂的粘接强度明显降低。     

Value of D-Dimers in patients with acute aortic dissection

Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P ＜ 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (＞0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P ＜0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P ＜ 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.     

Research of combined liver-kidney transplantation model in rats

Objective： To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods： SD rats served as both donors and recipients. 4℃ sodium lactate Ringer＇s was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava （IVC） inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results： Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion： This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.     

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P＜ 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P＜ 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.     

安心颗粒对急诊经皮冠状动脉介入术后生活质量影响的研究

目的：评价使用安心颗粒对急诊经皮冠状动脉介入术（PPCI）术后生活质量的影响.方法：将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组（术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次）和对照组（仅接受基础药物治疗）.所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表（MIDAS）、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果：入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异（P＞0.05）;出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低（P＜0.05）;组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低（P＜0.05）.两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血（P＞0.05）.两组发生轻度血小板减少症的患者数比较无差异（P＞0.05）.结论：PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.     

The comparative studies of the influences of Urapidil and Nicardipine on sino-atrial node function, atrio-ventricular node function and hemodynamics

Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P＜0.01);the MAP decreased(P＜0.01)and the HR increased drastically(P＜0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.     

Expression of OPGmRNA and ODFmRNA in the patients of hip fracture due to osteoporosis

Objective：To investigate the gene expression of osteoprotegerin（OPG） and osteoclast differentiation factor（ODF） in the bone tissue of patients with hip fracture due to osteoporosis. Methods：OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers（over 50 years old） with hip fracture（Observer Group） and 30 cases of hip facture sufferers with no osteoporosis（Control group） were analyzed with the Semi-Quantitative RT-PCR method. Results：The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion：Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.     

The clinicopathological and immuohistochemical analysis of solid-pseudopapillary tumor of the pancreas： report of 9 cases

Objective：To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas（SPTP）. Methods：Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin（HE） staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results：Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin（9/9 cases）, AAT（9/9 cases）, NSE（9/9 cases）, ACT（7/9 cases）, CK20（2/9 cases）, CgA（1/9 cases）, S-100（3/gcases）, PR（4/gcases）, Syn（3/9 cases） and CD56（5/9cases）, negative in CEA and ER. Conclusion：SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.     

Dynamic Changes in Serum Estradiol and Progesterone levels in Patients of Premenstrual Syndrome with Adverse Flow of Liver-qi

Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.     

Real-time Three-dimensional Echocardiography in Assessment of Left Ventricular and Right Ventricular Volumes

Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.     

SCREENING FOR A 21-CHROMOSOME ABNORMALITY IN PREIMPLANTED EMBRYOS OF ELDERLY WOMEN

Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.