ALB and cholestasis: Portal venous blood flow is related to liver functional reserve; ALT and AST are important indexes for liver cell injury, and increased ALT and AST levels indicate damage to hepatic parenchymal cells; ALP and γ-GGT levels indicate biliary obstruction and cholestasis at any level from the capillary bile duct to the common bile duct; ALB and PT levels reveal the synthetic function of liver (24–26).