Anatomy teaching and research section, Hebei Union University, Tangshan 063009, China;
Worker Hospital Affiliated to Hebei Medical University, Tangshan 063000, China;
Worker Hospital Affiliated to Hebei Medical University, Tangshan 063000, China;
Anatomy teaching and research section, Hebei Union University, Tangshan 063009, China;
Anatomy teaching and research section, Hebei Union University, Tangshan 063009, China;
Anatomy teaching and research section, Hebei Union University, Tangshan 063009, China;