obstructions障碍obstructionn.障碍；妨碍；闭塞；违例阻挡obstruction of nasolacrimal duct鼻泪管阻塞obstruction of Oddi rs sphincter奥狄氏括约肌阻塞obstruction sleep apnea syndrome鼾症Obstruction of precerebral artery大脑前动脉梗阻obstruction of male genital tract男性生殖道阻塞obstruction of superior vena cava上腔静脉梗阻Obstruction of lacrimal canaliculi泪小管梗阻Obstruction of lacrimal canaliduli泪总管狭窄obstruction of lacrimal canalidull泪总管阻塞obstruction of lacrimal canaliculus泪小管阻塞