Circadian relationships between interleukin-(IL)- 6 and hypothalamic-pituitary-adrenal axis hormones: failure of IL-6 to cause sustained hypercortisolism in patients with early untreated rheumatoid arthritis. - Crofford,L.J.; Kalogeras,K.T.; Mastorakos,G. (J Clin Endocrinol Metab, 1997)