Pengaruh Hipoksia Hipobarik Intermiten terhadap Heat Shock Protein 70 dan Produksi Sitokin TNF-?, IL-1? dan IL-10 pada Jaringan Hepar Tikus = The Effect of Intermittent Hypobaric Hypoxia on Heat Shock Protein 70 and Production of TNF-α, IL-1β, and IL-10 Cytokines in Rat Liver Tissue