Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and freque...Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and frequency dimension to cope with the temporal wind shear and achieve the optimal accumulation time.A hardware-efficient algorithm combining the interpolation and cross-correlation is used to enhance the wind retrieval accuracy by reducing the frequency sampling interval and then reduce the spectral width calculation error.Moreover,the temporal broadening effect and spatial broadening effect are decoupled according to the strategy we developed.展开更多
背景动态增强磁共振成像在肿瘤性质,血流灌注,预后评估等方面发挥着十分重要的作用.动态增强磁共振成像能定量分析肿瘤组织微循环血流灌注状态,可为临床术前评估提供有价值的血流动力学信息.目的探讨直肠癌动态增强磁共振成像(dynamic c...背景动态增强磁共振成像在肿瘤性质,血流灌注,预后评估等方面发挥着十分重要的作用.动态增强磁共振成像能定量分析肿瘤组织微循环血流灌注状态,可为临床术前评估提供有价值的血流动力学信息.目的探讨直肠癌动态增强磁共振成像(dynamic contrast-enhanced magnetic resonance image,DCE-MRI)定量灌注参数与血管内皮生长因子、微血管密度的相关性.方法选取在我院拟行手术切除治疗的65例直肠癌患者作为研究对象.所有患者术前均行DCE-MRI检查,测定病灶及其周围正常直肠壁的定量灌注参数:正向转运常数(forward transport constant,K^(trans))、反向转运常数(reverse transport constant,Kep)、容积分数(volume fraction,Ve)和起始曲线下面积(area under the starting curve,iAUC).采用免疫组织化学方法测定术后标本的血管内皮生长因子(vascular endothelial growth factor,VEGF)表达水平、微血管密度(microvessel density,MVD),分析DCE-MRI定量灌注参数与VEGF、MVD的相关性.结果直肠癌病灶的K^(trans)、Kep、Ve和iAUC均明显高于正常直肠壁,差异均有统计学意义(均P<0.05);直肠癌病灶的MVD和VEGF表达水平均明显高于正常直肠壁,差异均有统计学意义(均P<0.05);K^(trans)、Kep、Ve和iAUC与MVD均呈正相关,相关系数分别为r=0.76、r=0.70、r=0.46、r=0.68(均P<0.05);与VEGF表达水平均呈正相关,相关系数分别为r=0.72、r=0.67、r=0.41、r=0.64(均P<0.05).结论直肠癌DCE-MRI定量灌注参数能有效反映病灶的血流灌注状态,其中Ktrans与MVD、VEGF表达水平具有较好相关性,可为术前评估提供有价值的参考.展开更多
恶性纤维组织细胞瘤为一种罕见病,多误诊为不典型纤维黄色瘤或上皮样肉瘤。患者男,67岁。因左大腿内侧结节3月,进行性增大1月就诊。皮损组织病理检查示:肿瘤中成分呈多形性表现,部分细胞似成纤维细胞样交织排列呈漩涡状;有些细胞似组织...恶性纤维组织细胞瘤为一种罕见病,多误诊为不典型纤维黄色瘤或上皮样肉瘤。患者男,67岁。因左大腿内侧结节3月,进行性增大1月就诊。皮损组织病理检查示:肿瘤中成分呈多形性表现,部分细胞似成纤维细胞样交织排列呈漩涡状;有些细胞似组织细胞样,可见形状怪异的多核巨细胞。免疫组化:Vim(+)、CD163(+)、CD68(+)、CD34血管(+)、Ki-67 index 30%。展开更多
基金Project supported by the Shanghai Science and Technology Innovation Action(Grant No.22dz1208700).
文摘Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and frequency dimension to cope with the temporal wind shear and achieve the optimal accumulation time.A hardware-efficient algorithm combining the interpolation and cross-correlation is used to enhance the wind retrieval accuracy by reducing the frequency sampling interval and then reduce the spectral width calculation error.Moreover,the temporal broadening effect and spatial broadening effect are decoupled according to the strategy we developed.
文摘背景动态增强磁共振成像在肿瘤性质,血流灌注,预后评估等方面发挥着十分重要的作用.动态增强磁共振成像能定量分析肿瘤组织微循环血流灌注状态,可为临床术前评估提供有价值的血流动力学信息.目的探讨直肠癌动态增强磁共振成像(dynamic contrast-enhanced magnetic resonance image,DCE-MRI)定量灌注参数与血管内皮生长因子、微血管密度的相关性.方法选取在我院拟行手术切除治疗的65例直肠癌患者作为研究对象.所有患者术前均行DCE-MRI检查,测定病灶及其周围正常直肠壁的定量灌注参数:正向转运常数(forward transport constant,K^(trans))、反向转运常数(reverse transport constant,Kep)、容积分数(volume fraction,Ve)和起始曲线下面积(area under the starting curve,iAUC).采用免疫组织化学方法测定术后标本的血管内皮生长因子(vascular endothelial growth factor,VEGF)表达水平、微血管密度(microvessel density,MVD),分析DCE-MRI定量灌注参数与VEGF、MVD的相关性.结果直肠癌病灶的K^(trans)、Kep、Ve和iAUC均明显高于正常直肠壁,差异均有统计学意义(均P<0.05);直肠癌病灶的MVD和VEGF表达水平均明显高于正常直肠壁,差异均有统计学意义(均P<0.05);K^(trans)、Kep、Ve和iAUC与MVD均呈正相关,相关系数分别为r=0.76、r=0.70、r=0.46、r=0.68(均P<0.05);与VEGF表达水平均呈正相关,相关系数分别为r=0.72、r=0.67、r=0.41、r=0.64(均P<0.05).结论直肠癌DCE-MRI定量灌注参数能有效反映病灶的血流灌注状态,其中Ktrans与MVD、VEGF表达水平具有较好相关性,可为术前评估提供有价值的参考.
文摘恶性纤维组织细胞瘤为一种罕见病,多误诊为不典型纤维黄色瘤或上皮样肉瘤。患者男,67岁。因左大腿内侧结节3月,进行性增大1月就诊。皮损组织病理检查示:肿瘤中成分呈多形性表现,部分细胞似成纤维细胞样交织排列呈漩涡状;有些细胞似组织细胞样,可见形状怪异的多核巨细胞。免疫组化:Vim(+)、CD163(+)、CD68(+)、CD34血管(+)、Ki-67 index 30%。
