microscopic view of red blood cells in human blood, surface view - 19th century - 血球 幅插畫檔、美工圖案、卡通及圖標紅血球
normal artery and cholesterol blocked artery. clogged arteries caused by cholesterol. normal veins and varicose veins. - 血球 幅插畫檔、美工圖案、卡通及圖標阻塞, 血液流動