healthy controls:one blood sample (7.5 cc) hepatitis: three blood samples, at admission, at 3rd and 7-10th day of admission liver cirrhosis: two blood samples, at 1-2 years interval (7.5 cc/each session) hepatocellular carcinoma: three blood samples, before, 1 day after and at the 7th day of transcatheter arterial chembolizatiom