单项选择题
A.10~20Hu B.20~50Hu C.100Hu左右 D.-20~-10Hu E.-90~-70Hu或更低
A.关节腔 B.关节囊 C.关节软骨 D.关节囊和关节腔 E.关节腔和关节软骨
A.AndreasGruntzig B.CharlesDotter C.AlexanderMargulis D.WernerForssmann E.Sven-IvarSeldinger