目的:探讨127°小颈干角和135°大颈干角假体行全髋关节置换术(total hip arthroplasty,THA)的疗效。方法:2014年1月至2016年6月行THA患者84例,男44例,女40例;年龄45~72(53.4±8.1)岁,股骨头坏死68例(左侧32例,右侧36例),...目的:探讨127°小颈干角和135°大颈干角假体行全髋关节置换术(total hip arthroplasty,THA)的疗效。方法:2014年1月至2016年6月行THA患者84例,男44例,女40例;年龄45~72(53.4±8.1)岁,股骨头坏死68例(左侧32例,右侧36例),其他原因导致严重髋关节骨性关节炎16例,病程9~36(24.0±5.5)个月。分别采用小颈干角(127°)和大颈干角(135°)假体,每组42例,术后两组患者进行髋关节Harris评分,疼痛视觉模拟评分(visual analogue scale,VAS)评分,双下肢长度测量,不同颈干角生物力学评估,比较术后并发症发生情况以及患者术后24个月生活质量。结果:两组患者各有2例患者失访,其余患者均获得随访,随访时间30~36(33.0±1.6)个月。术前及术后1、6、12、24个月进行Harris评分及双下肢长度测量,两组患者髋关节Harris评分及双下肢长度差与术前比较均得到明显改善(P<0.05),而组间差异无统计学意义(P>0.05)。两组术后1、6、12、24个月VAS评分均低于术前(P<0.05);两组VAS评分术前差异无统计学意义(P>0.05),但术后大颈干角组VAS评分明显低于小颈干角组(P<0.05)。两组术后并发症(包括假体松动、脱位)的发生率差异无统计学意义(P>0.05)。两组患者术后24个月生活质量较术前生活质量明显提高(P<0.05),且组间比较发现135°大颈干角组生活质量较127°小颈干角组生活质量更高(P<0.05)。结论:大、小颈干角假体的THA均能较好地恢复患者髋关节的功能,但是大颈干角更能降低术后疼痛程度,进而提高患者术后的生活质量。展开更多
High grade pipeline steels were prepared using vacuum carbon deoxidization process combined with a final Ti-deoxidation process.The microstructure of the as-cast steels was investigated by using scanning electron micr...High grade pipeline steels were prepared using vacuum carbon deoxidization process combined with a final Ti-deoxidation process.The microstructure of the as-cast steels was investigated by using scanning electron microscopy（SEM）and transmission electron microscopy（TEM）.SEM observation shows that the formation of intragranular ferrite（IGF）structure is induced by fine inclusions.TEM selected area diffraction（SAD）patterns and elemental distribution analysis indicate that these inclusions are mainly Ti2O3 and MnS.It is also found that Ti2O3 may act as nucleus in the formation of MnS during solidification process.Raman spectroscopic analysis demonstrates the presence of another phase,MnTiO3,which could be formed through entrapment of Mn by Ti2O3.It is believed that the formation of Mn-depleted region in the inclusions and thus the formation of MnTiO3 phase will increase the Mn pickup from matrix and promote the formation of IGF during solidification of molten steel.展开更多
The level of the slag entrapment in mold involves the submerged nozzle immersion depth,the electromagnetic stirring intensity and other factors;this article has studied the relations between the slag entrapment behavi...The level of the slag entrapment in mold involves the submerged nozzle immersion depth,the electromagnetic stirring intensity and other factors;this article has studied the relations between the slag entrapment behavior and the above factors by using of the water model.The results show that the surface velocity in meniscus increases with the increasing of stirring intensity and the decreasing of submerged nozzle immersion depth.When the submerged nozzle immersion depth is shallower,and the stirring intensity is high,the interface turbulence of the molten steel and slag is more severe,slag entrapment may occur in the extreme state.In order to avoid the slag entrapment in the working condition,the submerged nozzle immersion depth should be increased from 85;0mm to 100mm,or the electric current of the electromagnetic stirring should be reduced from 320A to 295A.展开更多
文摘目的:探讨127°小颈干角和135°大颈干角假体行全髋关节置换术(total hip arthroplasty,THA)的疗效。方法:2014年1月至2016年6月行THA患者84例,男44例,女40例;年龄45~72(53.4±8.1)岁,股骨头坏死68例(左侧32例,右侧36例),其他原因导致严重髋关节骨性关节炎16例,病程9~36(24.0±5.5)个月。分别采用小颈干角(127°)和大颈干角(135°)假体,每组42例,术后两组患者进行髋关节Harris评分,疼痛视觉模拟评分(visual analogue scale,VAS)评分,双下肢长度测量,不同颈干角生物力学评估,比较术后并发症发生情况以及患者术后24个月生活质量。结果:两组患者各有2例患者失访,其余患者均获得随访,随访时间30~36(33.0±1.6)个月。术前及术后1、6、12、24个月进行Harris评分及双下肢长度测量,两组患者髋关节Harris评分及双下肢长度差与术前比较均得到明显改善(P<0.05),而组间差异无统计学意义(P>0.05)。两组术后1、6、12、24个月VAS评分均低于术前(P<0.05);两组VAS评分术前差异无统计学意义(P>0.05),但术后大颈干角组VAS评分明显低于小颈干角组(P<0.05)。两组术后并发症(包括假体松动、脱位)的发生率差异无统计学意义(P>0.05)。两组患者术后24个月生活质量较术前生活质量明显提高(P<0.05),且组间比较发现135°大颈干角组生活质量较127°小颈干角组生活质量更高(P<0.05)。结论:大、小颈干角假体的THA均能较好地恢复患者髋关节的功能,但是大颈干角更能降低术后疼痛程度,进而提高患者术后的生活质量。
基金Item Sponsored by Provincial Natural Science Foundation of Hubei Province of China(2006ABD006)Excellent Young Scientific and Technological Innovation Team Scheme of Hubei Universities of China(T200609)
文摘High grade pipeline steels were prepared using vacuum carbon deoxidization process combined with a final Ti-deoxidation process.The microstructure of the as-cast steels was investigated by using scanning electron microscopy（SEM）and transmission electron microscopy（TEM）.SEM observation shows that the formation of intragranular ferrite（IGF）structure is induced by fine inclusions.TEM selected area diffraction（SAD）patterns and elemental distribution analysis indicate that these inclusions are mainly Ti2O3 and MnS.It is also found that Ti2O3 may act as nucleus in the formation of MnS during solidification process.Raman spectroscopic analysis demonstrates the presence of another phase,MnTiO3,which could be formed through entrapment of Mn by Ti2O3.It is believed that the formation of Mn-depleted region in the inclusions and thus the formation of MnTiO3 phase will increase the Mn pickup from matrix and promote the formation of IGF during solidification of molten steel.
文摘The level of the slag entrapment in mold involves the submerged nozzle immersion depth,the electromagnetic stirring intensity and other factors;this article has studied the relations between the slag entrapment behavior and the above factors by using of the water model.The results show that the surface velocity in meniscus increases with the increasing of stirring intensity and the decreasing of submerged nozzle immersion depth.When the submerged nozzle immersion depth is shallower,and the stirring intensity is high,the interface turbulence of the molten steel and slag is more severe,slag entrapment may occur in the extreme state.In order to avoid the slag entrapment in the working condition,the submerged nozzle immersion depth should be increased from 85;0mm to 100mm,or the electric current of the electromagnetic stirring should be reduced from 320A to 295A.
