the following parameters were measured on all subjects : plasma renin activity and plasma and urinary aldosterone levels ( by radioimmunoassay ) , serum ionic calcium levels ( by nova-2 ) , total serum calcium , and serum and urinary magnesium values ( by atomic absorption ) , serum and urinary sodium and potassium levels ( by flame photometry ) , and creatinine clearance .
C0032105
plasma
C0229671
serum