The divalent state of Ln（III） ions has attracted much interest because of their ability to serve isomorphously in many biological system of divalent Ca（II） ion. Therefore, present paper deals with the study of div...The divalent state of Ln（III） ions has attracted much interest because of their ability to serve isomorphously in many biological system of divalent Ca（II） ion. Therefore, present paper deals with the study of divalent state of Eu（III） and Nd（III） ions in non-aqueous medium. In present study, cyclic voltammetry and chronopotentiometry were utilized to establish the divalent state of Eu（III） and Nd（III） ions. The cyclic voltammetric technique showed two-step reduction process at cathode for both Ln（III） ions under specified experimental conditions and chronopotentiometric method also showed two different transition times （r）. Looking to the shape of cyclic voltammogram we calculated het- erogeneous forward rate constant （K^fh, cm/s） and diffusion coefficient （D, cm2/s） for both ions, which suggested that sweep rate had great ef- fect on the shape of cyclic voltammogram of Eu（III） and Nd（III） ions. The result of chronopotentiometry also suggested that stable divalent states of Eu（III） and Nd（III） ions existed with chronopotentiogram with two distinct transition times. The diffusion coefficients （D, cm2/s） were calculated from Sand equation. The diffusion coefficients of both techniques were compared and the results suggested that the system at electrode surface was changing from being reversible to irreversible.展开更多
目的比较行固定平台和活动平台人工膝关节置换的患者术后的中期膝前痛情况。方法选取2006至2009年于首都医科大学附属北京同仁医院骨科行固定平台和活动平台膝关节置换的患者作为研究对象,将其分为固定平台组和活动平台组。所有患者均...目的比较行固定平台和活动平台人工膝关节置换的患者术后的中期膝前痛情况。方法选取2006至2009年于首都医科大学附属北京同仁医院骨科行固定平台和活动平台膝关节置换的患者作为研究对象,将其分为固定平台组和活动平台组。所有患者均未置换髌骨。记录患者术前术后膝前痛发生率、膝前痛评分、髌骨评分、KSS功能评分(Knee Society Function Score),并进行术前术后和两组间的比较。拍摄术后膝关节正侧位和Merchant位X线片,观察髌骨位置情况。结果共63人、85膝纳入研究。其中活动平台组31人、45膝,随访时间3.9~7.6年,平均(5.9±1.1)年。固定平台组30人、40膝,随访4.2~8.1年,平均(6.4±1.3)年。两组患者术后膝前痛评分、髌骨评分、KSS功能评分均较术前有明显提高,但两组患者间术后上述评分差异无统计学意义。两组患者间术后膝前痛发生率差异也无统计学意义。两组患者术后X-ray均未显示明显的髌骨脱位或半脱位。结论非置换髌骨的活动平台和固定平台膝关节置换术均可以有效地缓解膝前痛、恢复膝关节功能,术后中期效果满意。相比固定平台假体,活动平台假体的应用并未显著地改善术后膝前痛情况。展开更多
文摘The divalent state of Ln（III） ions has attracted much interest because of their ability to serve isomorphously in many biological system of divalent Ca（II） ion. Therefore, present paper deals with the study of divalent state of Eu（III） and Nd（III） ions in non-aqueous medium. In present study, cyclic voltammetry and chronopotentiometry were utilized to establish the divalent state of Eu（III） and Nd（III） ions. The cyclic voltammetric technique showed two-step reduction process at cathode for both Ln（III） ions under specified experimental conditions and chronopotentiometric method also showed two different transition times （r）. Looking to the shape of cyclic voltammogram we calculated het- erogeneous forward rate constant （K^fh, cm/s） and diffusion coefficient （D, cm2/s） for both ions, which suggested that sweep rate had great ef- fect on the shape of cyclic voltammogram of Eu（III） and Nd（III） ions. The result of chronopotentiometry also suggested that stable divalent states of Eu（III） and Nd（III） ions existed with chronopotentiogram with two distinct transition times. The diffusion coefficients （D, cm2/s） were calculated from Sand equation. The diffusion coefficients of both techniques were compared and the results suggested that the system at electrode surface was changing from being reversible to irreversible.
文摘目的比较行固定平台和活动平台人工膝关节置换的患者术后的中期膝前痛情况。方法选取2006至2009年于首都医科大学附属北京同仁医院骨科行固定平台和活动平台膝关节置换的患者作为研究对象,将其分为固定平台组和活动平台组。所有患者均未置换髌骨。记录患者术前术后膝前痛发生率、膝前痛评分、髌骨评分、KSS功能评分(Knee Society Function Score),并进行术前术后和两组间的比较。拍摄术后膝关节正侧位和Merchant位X线片,观察髌骨位置情况。结果共63人、85膝纳入研究。其中活动平台组31人、45膝,随访时间3.9~7.6年,平均(5.9±1.1)年。固定平台组30人、40膝,随访4.2~8.1年,平均(6.4±1.3)年。两组患者术后膝前痛评分、髌骨评分、KSS功能评分均较术前有明显提高,但两组患者间术后上述评分差异无统计学意义。两组患者间术后膝前痛发生率差异也无统计学意义。两组患者术后X-ray均未显示明显的髌骨脱位或半脱位。结论非置换髌骨的活动平台和固定平台膝关节置换术均可以有效地缓解膝前痛、恢复膝关节功能,术后中期效果满意。相比固定平台假体,活动平台假体的应用并未显著地改善术后膝前痛情况。
