sphincter muscle 括约肌

pupil sphincter muscle 瞳孔括约肌

pupillary sphincter muscle 瞳孔括约肌

nasopharyngeal sphincter muscle 鼻咽括约肌

sphincter muscle of pupil 瞳孔括约肌

sphincter muscle of urethra 尿道括约肌

external sphincter muscle anus 肛门外括约肌

sphincter muscle of bile duct 胆道括约肌

external sphincter muscle of anus 肛门外括约肌

sphincter muscle of urinary bladder 膀胱括约肌