A geometric model of relaxed plain-nitted fabric isproposed.A method based on the model for predictingthe loop length from the course spacing,wale spacing offabric and the diameter of yarn is deduced,as well as a comp...A geometric model of relaxed plain-nitted fabric isproposed.A method based on the model for predictingthe loop length from the course spacing,wale spacing offabric and the diameter of yarn is deduced,as well as a computer program is developed to graphically represent the structures of plain knitted fabric with various struc-tural parameters.展开更多
目的:探讨基于左心室压力-应变环(pressure-strain loop,PSL)的二维左心室整体纵向应变(two-dimensional left ventricular global longitudinal strain,2D-GLS)、心肌做功参数预测急性心肌梗死(acute myocardial infarction,AMI)患者PC...目的:探讨基于左心室压力-应变环(pressure-strain loop,PSL)的二维左心室整体纵向应变(two-dimensional left ventricular global longitudinal strain,2D-GLS)、心肌做功参数预测急性心肌梗死(acute myocardial infarction,AMI)患者PCI术后心肌灌注不良的价值。方法:收集117例2023年4月至2024年4月,在华中科技大学同济医学院附属梨园医院接受PCI术治疗的AMI患者的,根据术后是否发生心肌灌注不良将其分为心肌灌注不良组(n=26)及无心肌灌注不良组(n=91),并分析其PCI术前2D-GLS参数[心内膜下心肌节段整体纵向应变(global longitudinal strain of subendocardial myocardial segmen,GLSendo)、中层心肌节段整体纵向应变(global longitudinal strain of middle myocardial segment,GLSmid)、心外膜下心肌节段整体纵向应变(global longitudinal strain ofsubepicardialmyocardialsegment,GLSepi)]及心肌做功参数[整体有用功(globalconstructive work,GCW)、整体做功功率(global work efficiency,GWE)、整体做功指数(global work index,GWI)及整体无用功(global wasted work GWW)]预测AMI患者PCI术后发生心肌灌注不良的价值。结果:(1)常规超声显示,两组患者LVEDD、左心室舒张末期容积、左心室收缩末期容积及LVEF比较无明显差异(P>0.05);(2)二维应变成像显示,心肌灌注不良组患者GLSendo、GLSmid、GLSepi均较无心肌灌注不良组低(P<0.05);(3)二维应变成像显示,心肌灌注不良组患者GWW较无心肌灌注不良组高(P<0.05),GCW、GWE、GWI均较无心肌灌注不良组低(P<0.05);(4)AMI患者PCI术前GLSendo、GLSmid、GLSepi、GWW、GCW、GWE、GWI预测其PCI术后心肌灌注不良的效能较高,其中GWI的预测效能最高,其Youden指数最大时(0.747),预测PCI术后心肌灌注不良曲线下面积(AUC)为0.849,敏感度为92.8%,特异度为82.4%。结论:AMI心肌灌注不良患者PCI术前GWW异常增高,GLSendo、GLSmid、GLSepi、GCW、GWE、GWI异常降低,均可作为预测该类患者PCI术后心肌灌注不良的有效指标,其中GWI预测效能最高。展开更多
文摘A geometric model of relaxed plain-nitted fabric isproposed.A method based on the model for predictingthe loop length from the course spacing,wale spacing offabric and the diameter of yarn is deduced,as well as a computer program is developed to graphically represent the structures of plain knitted fabric with various struc-tural parameters.
文摘目的:探讨基于左心室压力-应变环(pressure-strain loop,PSL)的二维左心室整体纵向应变(two-dimensional left ventricular global longitudinal strain,2D-GLS)、心肌做功参数预测急性心肌梗死(acute myocardial infarction,AMI)患者PCI术后心肌灌注不良的价值。方法:收集117例2023年4月至2024年4月,在华中科技大学同济医学院附属梨园医院接受PCI术治疗的AMI患者的,根据术后是否发生心肌灌注不良将其分为心肌灌注不良组(n=26)及无心肌灌注不良组(n=91),并分析其PCI术前2D-GLS参数[心内膜下心肌节段整体纵向应变(global longitudinal strain of subendocardial myocardial segmen,GLSendo)、中层心肌节段整体纵向应变(global longitudinal strain of middle myocardial segment,GLSmid)、心外膜下心肌节段整体纵向应变(global longitudinal strain ofsubepicardialmyocardialsegment,GLSepi)]及心肌做功参数[整体有用功(globalconstructive work,GCW)、整体做功功率(global work efficiency,GWE)、整体做功指数(global work index,GWI)及整体无用功(global wasted work GWW)]预测AMI患者PCI术后发生心肌灌注不良的价值。结果:(1)常规超声显示,两组患者LVEDD、左心室舒张末期容积、左心室收缩末期容积及LVEF比较无明显差异(P>0.05);(2)二维应变成像显示,心肌灌注不良组患者GLSendo、GLSmid、GLSepi均较无心肌灌注不良组低(P<0.05);(3)二维应变成像显示,心肌灌注不良组患者GWW较无心肌灌注不良组高(P<0.05),GCW、GWE、GWI均较无心肌灌注不良组低(P<0.05);(4)AMI患者PCI术前GLSendo、GLSmid、GLSepi、GWW、GCW、GWE、GWI预测其PCI术后心肌灌注不良的效能较高,其中GWI的预测效能最高,其Youden指数最大时(0.747),预测PCI术后心肌灌注不良曲线下面积(AUC)为0.849,敏感度为92.8%,特异度为82.4%。结论:AMI心肌灌注不良患者PCI术前GWW异常增高,GLSendo、GLSmid、GLSepi、GCW、GWE、GWI异常降低,均可作为预测该类患者PCI术后心肌灌注不良的有效指标,其中GWI预测效能最高。
基金Foundation item:The project was aided financially by the Beijing Natural Science Fund(4822011)and Foundation Resarch Fund of Tsinghua University(200110001)
