【摘要】 <正> 胆结石是常见病,在腹部外科死亡原因中仅低于恶性肿瘤。我国常见的是胆色素为主的混合结石,主要成分是胆红素。最近不少学者认为钙在胆石形成中起着重要作用。胆石是胆红素的钙盐或钙参加的复杂高聚物。为研究钙离子在胆石形成中作用,有必要测定胆汁中离子钙浓度。更多还原

【Abstract】 Ionized calcium is one of the important factors in the formation of gallstones.In order to study its role, the determination of ultrafiltrable calcium in bile with atomic absorption spectroscopy had been reported . But the concentration of ultrafiltrable Calcium cannot represent that of ionized calcium.In this paper, it is shown that the concentration of ionized calcium in bile can be determined with Calcium ion selective electrode directly and conveniently,.Calcium ion selective electrode was calibrated by 10-2 to 10-5 M CaCl2 in 0.15 M NaCl solution.The effects of the inorganic cations and main organic components in human bile on calcium ion selective electrode were investigated, and a method for measuring ionized calcium concentration was established. The range of ionized calcium concentration in the bile of patients with pigment gallstones is 10-4 to 10-3 M.In studying pathogenesis and dissolution of gallstones, ionized calcium concentration may be as low as less than 10-5M.For this reason, calcium ion selective electrode was calibrated by ion buffer solution consisting of 1×10-3M CaCl2, 5×10-8 M EDTA in 0.15 M NaCl solution,The pH value of that was adjusted to 5-8.The limit of detection may be extended to 10-8 M.This method makes it possible to determine ionized calcium concentration in studying pathogenesis, prevention and dissolution of gallstones.更多还原