Objective To comparatively observe changes in the expressions of hypoxia inducible factor-1α(HIF-1α) and cyclooxygenase-2(COX-2) in human hepatocellular carcinoma cells under hypoxic conditions as well as the interfering effect of saikosaponin d,and explore the influence of saikosaponin d on HIF-1α /COX-2 pathway.Methods ① Cobalt chloride was used to simulate cell hypoxia to observe the expressions of HIF-1α and COX-2 in human hepatocellular carcinoma cell line SMMC-7721 under hypoxic conditions.② Cobalt ch...