目的探讨基于CT三维重建技术获得的肾结石物理特征对软性输尿管镜碎石术(flexible ureteroscopic lithotripsy,FURL)碎石效能的影响。方法选取四川大学华西空港医院自2021年7月至2022年12月符合入组条件的86例肾结石患者。术前通过CT三...目的探讨基于CT三维重建技术获得的肾结石物理特征对软性输尿管镜碎石术(flexible ureteroscopic lithotripsy,FURL)碎石效能的影响。方法选取四川大学华西空港医院自2021年7月至2022年12月符合入组条件的86例肾结石患者。术前通过CT三维重建技术测定肾结石的各个物理特征,包括结石数量(个)、结石长径(mm)、结石密度(Hu)、结石体积(cm^(3))和结石质量(Hu*cm^(3))。入选患者均接受FURL治疗,FURL术后根据结石清除状态分为结石清除组和结石残留组,采用多因素二元logistic回归分析法分析肾结石患者FURL术后结石清除率的影响因素。绘制受试者工作特征(receiver operating characteristic,ROC)曲线,分析各结石特征预测肾结石患者FURL术后结石清除的价值。采用Spearman相关系数分析各结石特征与手术时间的相关性。结果结石清除组为67例,结石残留组为19例,结石清除率为77.9%。多因素分析结果显示,结石长径、结石密度、结石体积及结石质量均为影响FURL术后结石清除率的独立危险因素(P<0.05)。ROC曲线显示,结石长径、结石密度、结石体积及结石质量的特征因素曲线下面积(area under the curve,AUC)分别为0.891、0.674、0.919、0.957,结石质量预测结石清除率的效能明显优于其余结石特征因素。Spearman相关系数表明,结石长径、结石密度、结石体积、结石质量与手术时间均呈正相关(r=0.521、0.226、0.573、0.611,P<0.05),结石质量与手术时间相关性更高。结论基于CT三维重建技术获取的结石长径、密度、体积及质量等均是影响FURL术治疗肾结石的危险因素。其中,结石质量作为结石负荷指标可以更好地预测FURL术治疗肾结石的碎石效能。展开更多
Aiming at machining deeply small holes in TC4 alloy,a series of experiments were carried out on a self-developed multi-axis micro electrical discharge machining(micro-EDM)machine tool.To improve machining efficiency a...Aiming at machining deeply small holes in TC4 alloy,a series of experiments were carried out on a self-developed multi-axis micro electrical discharge machining(micro-EDM)machine tool.To improve machining efficiency and decrease relative wear of electrode in machining deeply small hole in TC4 alloy,many factors in micro-EDM,such as polarity,electrical parameters and supplying ways of working fluid were studied.Experimental results show that positive polarity machining is far superior to negative polarity machining;it is more optimal when open-circuit voltage,pulse width and pulse interval are 130 V,5μs and 15μs respectively on the self developed multi-axis micro-EDM machine tool;when flushing method is applied in micro-EDM,the machining efficiency is higher and relative wear of electrode is smaller.展开更多
The isotope shifts and hyperfine structures of seven optical transitions for all seven stable isotopes of Nd II were measured by using collinear fast-ion-beam laser spectroscopy.The nuclear parameterλwas obtained fro...The isotope shifts and hyperfine structures of seven optical transitions for all seven stable isotopes of Nd II were measured by using collinear fast-ion-beam laser spectroscopy.The nuclear parameterλwas obtained from the measured optical isotope shifts for all seven stable isotopes with improved accuracy.Theλvalues were analysed by using the Fermi distribution for the nuclear charge density.The values of δ<r^(2)>,δ<r^(4)>and δ<r^(6)>were determined.展开更多
文摘目的探讨基于CT三维重建技术获得的肾结石物理特征对软性输尿管镜碎石术(flexible ureteroscopic lithotripsy,FURL)碎石效能的影响。方法选取四川大学华西空港医院自2021年7月至2022年12月符合入组条件的86例肾结石患者。术前通过CT三维重建技术测定肾结石的各个物理特征,包括结石数量(个)、结石长径(mm)、结石密度(Hu)、结石体积(cm^(3))和结石质量(Hu*cm^(3))。入选患者均接受FURL治疗,FURL术后根据结石清除状态分为结石清除组和结石残留组,采用多因素二元logistic回归分析法分析肾结石患者FURL术后结石清除率的影响因素。绘制受试者工作特征(receiver operating characteristic,ROC)曲线,分析各结石特征预测肾结石患者FURL术后结石清除的价值。采用Spearman相关系数分析各结石特征与手术时间的相关性。结果结石清除组为67例,结石残留组为19例,结石清除率为77.9%。多因素分析结果显示,结石长径、结石密度、结石体积及结石质量均为影响FURL术后结石清除率的独立危险因素(P<0.05)。ROC曲线显示,结石长径、结石密度、结石体积及结石质量的特征因素曲线下面积(area under the curve,AUC)分别为0.891、0.674、0.919、0.957,结石质量预测结石清除率的效能明显优于其余结石特征因素。Spearman相关系数表明,结石长径、结石密度、结石体积、结石质量与手术时间均呈正相关(r=0.521、0.226、0.573、0.611,P<0.05),结石质量与手术时间相关性更高。结论基于CT三维重建技术获取的结石长径、密度、体积及质量等均是影响FURL术治疗肾结石的危险因素。其中,结石质量作为结石负荷指标可以更好地预测FURL术治疗肾结石的碎石效能。
基金Project(2006AA04Z323)supported by High-tech Research and Development Program of China。
文摘Aiming at machining deeply small holes in TC4 alloy,a series of experiments were carried out on a self-developed multi-axis micro electrical discharge machining(micro-EDM)machine tool.To improve machining efficiency and decrease relative wear of electrode in machining deeply small hole in TC4 alloy,many factors in micro-EDM,such as polarity,electrical parameters and supplying ways of working fluid were studied.Experimental results show that positive polarity machining is far superior to negative polarity machining;it is more optimal when open-circuit voltage,pulse width and pulse interval are 130 V,5μs and 15μs respectively on the self developed multi-axis micro-EDM machine tool;when flushing method is applied in micro-EDM,the machining efficiency is higher and relative wear of electrode is smaller.
基金Supported by the National Natural Science Foundation of China under Grant No.19984015.
文摘The isotope shifts and hyperfine structures of seven optical transitions for all seven stable isotopes of Nd II were measured by using collinear fast-ion-beam laser spectroscopy.The nuclear parameterλwas obtained from the measured optical isotope shifts for all seven stable isotopes with improved accuracy.Theλvalues were analysed by using the Fermi distribution for the nuclear charge density.The values of δ<r^(2)>,δ<r^(4)>and δ<r^(6)>were determined.
