2.9. Liver histopathology score

Histopathology scoring of liver sections, evaluating the degree of liver necrosis, was performed by a pathologist as previously described [24]. In brief, the grading was 0, no lesion present; 1/2, individual necrotic cells seen at the first cell layer adjacent to the central vein, and hyaline degeneration present; 1, necrotic cells extending two or three cell layers from the central veins; 2, necrotic cells extending three to six cell layers from the central veins, but limited in peripheral distribution; 3, the same as 2, but with necrosis extending from one central vein to another; 4, more severe than 3, with extensive centrilobular necrosis throughout the section.