Paraumbilical vein and portal hypertension: ultrasound doppler haemodynamic evaluation - Oliveira, Ilka Regina Souza de; Widman, Azzo; Fukushima, Julia Tizue; Saad, William Abrão; Gama Rodrigues, Joaquim José; Cerri, Giovanni (Annual International Symposium on Contrast Agents in Ultrasound, 2001)