aminotransferase times uln alanine alt aspartate ast liver hepatic upper aminotransferase uln involvement alt ast alanine aspartate liver cancer subjects alanine aminotransferase alt uln hepatic laboratory days iu involvement unless aminotransferase aspartate alanine ast alt uln institutional normal unless serum aspartate aminotransferase ast uln hepatic days times metastases laboratory iu aminotransferase uln ast alt liver aspartate alanine metastases present metastasis amino transferase uln alt ast aspartate alanine aminotransferase liver times iuln aminotransferase ast alt aspartate alanine liver metastases registration days uln liver alt metastases alanine present aminotransferase metastasis transaminase ast aminotransferase uln obtained aspartate alanine ast alt registration days prior