title: Diagnostic accuracy of ultrasound above and below the beta-hCG discriminatory zone.
authors.forename: M A
authors.initials: MA
authors.lastname: Kohn
mesh_terms: D000022:Abortion, Spontaneous / Q000097:blood / Q000000981:diagnostic imaging; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011271:Pregnancy, Ectopic / Q000097:blood* / Q000000981:diagnostic imaging*; D016216:Ultrasonography, Prenatal
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human