Age-related changes of serum sex hormones, insulin-like growth factor-1 and sex hormone binding globulin levels in men: cross sectional data from a healthy male cohort. - Leifke,E.; Gorenoi,V.; Wichers,C.; von zur Mühlen,A.; von Büren,E.; Brabant,G. (Clin Endocrinol (Oxf), 2000)