[Ultrasonography in the surveillance of the uterine cervix during pregnancy].
Yu
H
H
Li
W
W
D002584:Cervix Uteri / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007752:Obstetric Labor, Premature / Q000000981:diagnostic imaging*; D011247:Pregnancy; D014463:Ultrasonography; D002581:Uterine Cervical Incompetence / Q000000981:diagnostic imaging*