Molokhia M, Sturniolo G, Shields R, Turnberg L A
Am J Clin Nutr. 1980 Apr;33(4):881-6. doi: 10.1093/ajcn/33.4.881.
Using a short-lived isotope of zinc (69mZn) with a half-life of 13.9 hr, we have developed a simple test of zinc absorption. After an oral dose of isotope (50 muCi) with 2 mg of elemental zinc a plasma appearance curve was constructed from radioactivity determined in blood samples taken sequentially over 8 hr. Two week later an iv dose of isotope (25 muCi) was administered and a plasma disappearance curve was constructed. Absorption was calculated by computer analysis of appearance and disappearance curves using a deconvolution programme. Mean absorption in five normal subjects was 61% (range 41 to 79%). In three subjects given food with, or 1 hr before the isotope, absorption was delayed and reduced to less than 20% of the oral dose at 8 hr. This test of zinc absorption is simple to perform and, because the isotope has a short half-life, has the advantage of subjecting patients to only limited radiation.
我们使用半衰期为13.9小时的锌的一种短寿命同位素（69mZn），开发出了一种简单的锌吸收测试方法。口服一定剂量的同位素（50微居里）以及2毫克元素锌后，通过对在8小时内依次采集的血样中的放射性进行测定，绘制出一条血浆出现曲线。两周后，静脉注射一定剂量的同位素（25微居里），并绘制出一条血浆消失曲线。使用反卷积程序通过对出现曲线和消失曲线进行计算机分析来计算吸收情况。五名正常受试者的平均吸收为61%（范围为41%至79%）。在三名在服用同位素的同时或提前1小时进食的受试者中，吸收延迟，且在8小时时降至口服剂量的20%以下。这种锌吸收测试操作简单，而且由于该同位素半衰期短，具有使患者仅接受有限辐射的优点。
