radio-calcium absorption , plasma 25-hydroxyvitamin d [ 25- ( oh ) d ] and 1,25-dihydroxyvitamin d [ 1,25- ( oh ) 2d ] concentrations were measured in 19 elderly women with , and 21 without , vertebral fractures , before and after treatment with 25-hydroxyvitamin d3 [ 25- ( oh ) d3 ] , to establish whether malabsorption of calcium in elderly women with vertebral fractures has a cause different from that in elderly women without vertebral fractures .
C0006657
25-hydroxyvitamin d3
C2713074
25