passages.id: split_4_test_1082_passage
passages.type: progene_text
passages.text: We examined the plasma levels of interleukin 6 ( IL-6 ) , interleukin 1 receptor antagonist ( IL-1ra ) and C - reactive protein ( CRP ) in two independent studies : study A , Jungfraujoch , Switzerland , three overnight stays at 3458 m , n = 12 ; study B : Capanna Regina Margherita , Italy , 3 overnight stays at 3647 m and one overnight stay at 4559 m , n = 10 .