Manzke E, Chesnut C H, Wergedal J E, Baylink D J, Nelp W B
Metabolism. 1975 May;24(5):605-15. doi: 10.1016/0026-0495(75)90140-7.
The relationship between total body calcium (TBC) and local bone calcium mass (BCM) was studied in a group of osteoporotic patients (12 females and two males) with a wide range of body size. Two methods were used to estimate BCM: photon absorptiometry and radiographic morphometry. TBC was estimated by total-body neutron-activation analysis. Since 99 percent of TBC is located in the skeleton, it was assumed that TBC was essentially a measure of total skeletal (calcium) mass. TBC ranged from 482 to 1076 g. High correlations with r values from 0.84 to 0.94, p less than 0.001, were found between TBC and BCM measured by absorptiometry at six different sites of radius, ulna, and humerus. Additionally, high correlations with r values from 0.89 to 0.95, p less than 0.001, were found between BCM at the distal tenth of the radius and BCM at the five other sites. A high correlation was also found between body height and TBC, but partial correlations indicated that this accounted for very little of the correlation between TBC and BCM. In contrast to the above, correlations between BCM determined by radiographic morphometry and TBC were weak or nonsignificant. When TBC and BCM were expressed as percent of their mean value, the slopes of the estimating equations, describing the relationships between TBC and BCM, were essentially the same, but significantly less than one, which is the value of the slope expected if TBC and BCM had changed at the same relative rate. From these relationships, we conclude (1) that the rate of change in BCM was similar in the six sites examined, and (2) that the rate of change in these six sites was relatively more rapid than the change in total body calcium. Whether the change in rate of BCM was related to rate of increase during attainment of maximum BCM or subsequent rate of loss of BCM or both remains to be determined.
在一组体型差异较大的骨质疏松患者（12名女性和2名男性）中，研究了全身钙（TBC）与局部骨钙质量（BCM）之间的关系。使用了两种方法来估计BCM：光子吸收法和放射形态测量法。通过全身中子活化分析来估计TBC。由于99%的TBC位于骨骼中，因此假定TBC基本上是总骨骼（钙）质量的一种度量。TBC范围为482至1076克。在桡骨、尺骨和肱骨的六个不同部位，通过吸收法测量的TBC与BCM之间发现了高度相关性，r值在0.84至0.94之间，p小于0.001。此外，在桡骨远端十分之一处的BCM与其他五个部位的BCM之间发现了高度相关性，r值在0.89至0.95之间，p小于0.001。还发现身高与TBC之间存在高度相关性，但偏相关性表明，这在TBC与BCM之间的相关性中所占比例非常小。与上述情况相反，通过放射形态测量法确定的BCM与TBC之间的相关性较弱或不显著。当TBC和BCM以其平均值的百分比表示时，描述TBC与BCM之间关系的估计方程的斜率基本相同，但显著小于1，而如果TBC和BCM以相同的相对速率变化，预期斜率的值应为1。从这些关系中，我们得出结论：（1）在所检查的六个部位中，BCM的变化率相似；（2）这六个部位的变化率相对全身钙的变化更为迅速。BCM变化率的改变是与达到最大BCM时的增加率有关，还是与随后BCM的丢失率有关，抑或是与两者都有关，仍有待确定。
