目的:分析儿童肝脏未分化胚胎性肉瘤(undifferentiated embryonal sarcoma of the liver,UESL)的超声、CT及MRI影像学表现,以提高对该病的认识水平。方法:回顾性收集2009年12月至2021年12月首都儿科研究所附属儿童医院经手术及病理证实...目的:分析儿童肝脏未分化胚胎性肉瘤(undifferentiated embryonal sarcoma of the liver,UESL)的超声、CT及MRI影像学表现,以提高对该病的认识水平。方法:回顾性收集2009年12月至2021年12月首都儿科研究所附属儿童医院经手术及病理证实的11例儿童UESL,分析所有患儿的超声、CT及MRI影像表现,总结其影像学特点。结果:病灶均为单发,肿块最大径11.5~19.8 cm。CT平扫显示所有病灶边缘较清楚、其内呈不均匀低密度,内可见厚薄不均的分隔;囊性密度区边缘或分隔周围可见少许片絮样软组织密度影。6例超声图像均提示实性占位,表现为混合回声的实性包块内可见大小不等的无回声区。3例MRI表现为边界清楚肿块影,T1WI呈不均匀混杂低信号,病灶内可见高信号区;T2WI呈混合高信号区和条状低信号区。9例病灶增强扫描动脉期均以边缘强化为主,8例可见迂曲增粗血管影;延迟期病灶呈持续不均匀强化,边缘持续强化,且从外围向中心充盈,强化范围增大,8例延迟期可见假包膜。结论:儿童UESL影像学表现有一定特征性,了解其影像特点并结合临床特征,有助于早期诊断。展开更多
According to the characteristic of cruise missiles,navigation point setting is simplified,and the principle of route planning for saturation attack and a concept of reference route are put forward.With the help of the...According to the characteristic of cruise missiles,navigation point setting is simplified,and the principle of route planning for saturation attack and a concept of reference route are put forward.With the help of the shortest-tangent idea in route-planning and the algorithm of back reasoning from targets,a reference route algorithm is built on the shortest range and threat avoidance.Then a route-flight-time algorithm is built on navigation points.Based on the conditions of multi-direction saturation attack,a route planning algorithm of multi-direction saturation attack is built on reference route,route-flight-time,and impact azimuth.Simulation results show that the algorithm can realize missiles fired in a salvo launch reaching the target simultaneously from different directions while avoiding threat.展开更多
文摘目的:分析儿童肝脏未分化胚胎性肉瘤(undifferentiated embryonal sarcoma of the liver,UESL)的超声、CT及MRI影像学表现,以提高对该病的认识水平。方法:回顾性收集2009年12月至2021年12月首都儿科研究所附属儿童医院经手术及病理证实的11例儿童UESL,分析所有患儿的超声、CT及MRI影像表现,总结其影像学特点。结果:病灶均为单发,肿块最大径11.5~19.8 cm。CT平扫显示所有病灶边缘较清楚、其内呈不均匀低密度,内可见厚薄不均的分隔;囊性密度区边缘或分隔周围可见少许片絮样软组织密度影。6例超声图像均提示实性占位,表现为混合回声的实性包块内可见大小不等的无回声区。3例MRI表现为边界清楚肿块影,T1WI呈不均匀混杂低信号,病灶内可见高信号区;T2WI呈混合高信号区和条状低信号区。9例病灶增强扫描动脉期均以边缘强化为主,8例可见迂曲增粗血管影;延迟期病灶呈持续不均匀强化,边缘持续强化,且从外围向中心充盈,强化范围增大,8例延迟期可见假包膜。结论:儿童UESL影像学表现有一定特征性,了解其影像特点并结合临床特征,有助于早期诊断。
基金supported by the Aeronautical Science Foundation of China (20085584010)
文摘According to the characteristic of cruise missiles,navigation point setting is simplified,and the principle of route planning for saturation attack and a concept of reference route are put forward.With the help of the shortest-tangent idea in route-planning and the algorithm of back reasoning from targets,a reference route algorithm is built on the shortest range and threat avoidance.Then a route-flight-time algorithm is built on navigation points.Based on the conditions of multi-direction saturation attack,a route planning algorithm of multi-direction saturation attack is built on reference route,route-flight-time,and impact azimuth.Simulation results show that the algorithm can realize missiles fired in a salvo launch reaching the target simultaneously from different directions while avoiding threat.
