1[6]Ertberg BS,Kliewer MA,Bowie JD.Adnexal ring sign and he-moperitoneum caused by hemorrhagic ovarian cyst:pitfall in the sonographic diagnosis of ectopic pregnancy[J].AJR,1999,173(5):1301-1302.
2[1]Kory LA.Diagnosis of ectopic pregnancy[J].AJR,2000,175(4):1185-1186.
3[2]Frates MC,Doubijet PM,Durfee SM,et al.Sonographic and Doppler characteristics of the corpus luteum: can they predict pregnancy outcome[J]?J Ultrasound Med,2001,20(8):821-827.
4[3]Brown DL,Doubilet PM. Transvaginal sonography for diagno-sing ectopic pregnancy:positivity criteria and performance characteristics [J].J Ultrasound Med,1994,13(2):259-266.
5[4]Durfee SM,Frates MC.Sonographic spectrum of the corpus lute-um in early pregnancy:gray-scale,color,and pulsed Doppler appearance[J].J Clin Ultrasound,1999,2(1):55-59.
6[5]Comparision of tubal ring and corpus luteum echogenicities [J].J Ultrasound Med,2001,20(1):27-31.