This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Mul...This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Multiple quaternion-based extended Kalman filters were implemented to estimate the absolute orientations to achieve high accuracy.Under the guidance of ornithology experts, the extending/contracting motions and flapping cycles were recorded using the developed motion capture system, and the orientation of each bone was also analyzed. The captured flapping gesture of the Falco peregrinus is crucial to the motion database of raptors as well as the bionic design.展开更多
目的:分析门静脉海绵样变性(Cavernous transformation of the portal ven CTPV)三维动态增强磁共振血管成像的表现和特征,探讨对本病诊断及其价值。方法:回顾性分析了24例门静脉海绵样变的磁共振血管成像的图像,观察了其特征性的磁共...目的:分析门静脉海绵样变性(Cavernous transformation of the portal ven CTPV)三维动态增强磁共振血管成像的表现和特征,探讨对本病诊断及其价值。方法:回顾性分析了24例门静脉海绵样变的磁共振血管成像的图像,观察了其特征性的磁共振门静脉成像的表现,所有病例均经临床、实验室及彩超检查,其中14例经手术治疗,2例肝癌门脉主干癌栓伴CTPV患者行肝动脉化疗栓塞术。结果:本组24例CTPV以门静脉主干CTPV为主10例,门静脉主干及左右支均受累者8例,单纯左支或右支4例,肠系膜上静脉水平发生者2例。9例门静脉成像清楚地显示,数条迂曲的侧支循环静脉跨过阻塞部位向肝内匐形延伸,其中7例可在网状、管状扩张的门静脉内见细条状、小点状低信号的栓子,6例清楚地显示,门静脉全程多条细小迂曲的侧支循环静脉缠绕在一起,扭曲成网状血管结构的影像,其它15例见离肝性侧支循环静脉走行、分布情况。结论:三维动态增强磁共振血管成像能准确地提供CTPV位置、严重程度的信息,可直观地评价CTPV,为临床采取正确的治疗措施提供更多有重要价值的信息。展开更多
将40例术前放疗直肠癌患者随机分为A组和B组各20例。 A 组采用传统仰卧位小真空垫固定法， B组采用俯卧位热塑体膜＋有孔腹板固定法。两组病例均通过放疗前CT模拟定位、三维图像重建、靶区及正常危及器官的勾画，治疗计划采用5-7d调强...将40例术前放疗直肠癌患者随机分为A组和B组各20例。 A 组采用传统仰卧位小真空垫固定法， B组采用俯卧位热塑体膜＋有孔腹板固定法。两组病例均通过放疗前CT模拟定位、三维图像重建、靶区及正常危及器官的勾画，治疗计划采用5-7d调强放射治疗（IMRT），在剂量-体积直方图（DVH）上计算两组小肠、膀胱、股骨头的受量。治疗中拍摄验证片，与治疗前定位治疗计划系统（TPS）输出的3D数字重建图像进行对比，通过计算机专用软件测量摆位误差。两种固定方式的股骨头受量差异无统计学意义（t=0.35，P＞0.05），小肠剂量B组低于A组差异有统计学意义（t=2.42，P＜0.05），膀胱受量A组低于B组，但差异无统计学意义（t=0.85，P＞0.05）。摆位误差比较，B组左右及前后方向的摆位误差明显低于A组，差异有统计学意义（t=2.63，P＜0.05；t=2.22，P＜0.05），头脚方向的差异无统计学意义（t=1.32，P＞0.05）。在直肠癌术前调强放疗中，俯卧位体膜＋有孔腹板固定法在减少小肠的受照剂量及减少盆腔野头脚和前后方向的摆位误差方面具有优势。展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.52175279 and 51705459)the Natural Science Foundation of Zhejiang Province,China (Grant No.LY20E050022)the Key Research and Development Projects of Zhejiang Provincial Science and Technology Department (Grant No.2021C03122)。
文摘This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Multiple quaternion-based extended Kalman filters were implemented to estimate the absolute orientations to achieve high accuracy.Under the guidance of ornithology experts, the extending/contracting motions and flapping cycles were recorded using the developed motion capture system, and the orientation of each bone was also analyzed. The captured flapping gesture of the Falco peregrinus is crucial to the motion database of raptors as well as the bionic design.
文摘目的:分析门静脉海绵样变性(Cavernous transformation of the portal ven CTPV)三维动态增强磁共振血管成像的表现和特征,探讨对本病诊断及其价值。方法:回顾性分析了24例门静脉海绵样变的磁共振血管成像的图像,观察了其特征性的磁共振门静脉成像的表现,所有病例均经临床、实验室及彩超检查,其中14例经手术治疗,2例肝癌门脉主干癌栓伴CTPV患者行肝动脉化疗栓塞术。结果:本组24例CTPV以门静脉主干CTPV为主10例,门静脉主干及左右支均受累者8例,单纯左支或右支4例,肠系膜上静脉水平发生者2例。9例门静脉成像清楚地显示,数条迂曲的侧支循环静脉跨过阻塞部位向肝内匐形延伸,其中7例可在网状、管状扩张的门静脉内见细条状、小点状低信号的栓子,6例清楚地显示,门静脉全程多条细小迂曲的侧支循环静脉缠绕在一起,扭曲成网状血管结构的影像,其它15例见离肝性侧支循环静脉走行、分布情况。结论:三维动态增强磁共振血管成像能准确地提供CTPV位置、严重程度的信息,可直观地评价CTPV,为临床采取正确的治疗措施提供更多有重要价值的信息。
文摘将40例术前放疗直肠癌患者随机分为A组和B组各20例。 A 组采用传统仰卧位小真空垫固定法， B组采用俯卧位热塑体膜＋有孔腹板固定法。两组病例均通过放疗前CT模拟定位、三维图像重建、靶区及正常危及器官的勾画，治疗计划采用5-7d调强放射治疗（IMRT），在剂量-体积直方图（DVH）上计算两组小肠、膀胱、股骨头的受量。治疗中拍摄验证片，与治疗前定位治疗计划系统（TPS）输出的3D数字重建图像进行对比，通过计算机专用软件测量摆位误差。两种固定方式的股骨头受量差异无统计学意义（t=0.35，P＞0.05），小肠剂量B组低于A组差异有统计学意义（t=2.42，P＜0.05），膀胱受量A组低于B组，但差异无统计学意义（t=0.85，P＞0.05）。摆位误差比较，B组左右及前后方向的摆位误差明显低于A组，差异有统计学意义（t=2.63，P＜0.05；t=2.22，P＜0.05），头脚方向的差异无统计学意义（t=1.32，P＞0.05）。在直肠癌术前调强放疗中，俯卧位体膜＋有孔腹板固定法在减少小肠的受照剂量及减少盆腔野头脚和前后方向的摆位误差方面具有优势。
