Behne D, Brätter P, Herzfeld U, Kraft D
Klin Wochenschr. 1978 Jan 15;56(2):69-74. doi: 10.1007/BF01480086.
The calcium absorption was determined in 8 healthy test persons (average age 25.6 years) after oral administration of 500 mg and 1000 mg of this element. A double isotope method with enriched stable calcium isotopes was used which can be applied without any restriction as, unlike in radiotracer techniques, any exposure to ionizing radiation is avoided. The calcium administered orally was labelled with 48Ca, the CaCl2 injected intravenously with 46Ca. The determination of both isotopes in serum and urine samples was carried out by means of neutron activation analysis. Independent of the calcium dose given, an absorption of 30% was found. From the 46Ca content in the serum samples a mean value of 6.4 +/- 1.0 g calcium or 98.8 +/- 15.4 mg Ca/kg body weight was calculated for the 24 hr-exchangeable calcium body pool.
在8名健康受试人员（平均年龄25.6岁）口服500毫克和1000毫克该元素后，测定了钙的吸收情况。采用了一种使用富集稳定钙同位素的双同位素方法，该方法可以不受任何限制地应用，因为与放射性示踪技术不同，它避免了任何电离辐射暴露。口服的钙用48Ca标记，静脉注射的氯化钙用46Ca标记。通过中子活化分析测定血清和尿液样本中的两种同位素。发现无论给予的钙剂量如何，吸收率均为30%。根据血清样本中的46Ca含量，计算出24小时可交换钙体池的平均钙含量为6.4±1.0克钙或98.8±15.4毫克钙/千克体重。
