Patients undergoing abdominal surgery and using morphine pain control analgesia (PCA) device will be involved. Pre- and Post- operative (after anesthesia and at the end of surgery) blood sampling (total 30 ml) plus normal liver tissue (10mm3) e will be harvested. Above protein(TM, IL-20, HD) amount change will be measured (ELISA for TM, IL-20 (serum) or flowcytometry (white cells) for TM, HD, IL-20 expression, stain or blotting for skin tissue). Patients will be included in this branch to check the correlation between morphine consumption and protein expression. Pain questionnaire (BPI, McGill) will be applied for pain evaluation. 2-D gel analysis will also be applied to screen further possible molecules.