Department of Pediatric Surgery;
Hokkaido University Hospital;
Sapporo 060-8648;
Japan;
Department of Gastroenterological Surgery I;
Hokkaido University Graduate School of Medicine;
Sapporo 060-8638;
Japan;
Biliary; atresia; Bone; fractur; Hepatic; osteodystrophy; Kasai; hepatic; portoenterostomy; Vitamin; Ddeficiency;