RT Journal Article SR Electronic T1 Introduction JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP S2 OP S2 DO 10.3949/ccjm.78.s2.01 VO 78 IS 11 suppl 2 A1 Leonard Calabrese YR 2011 UL http://www.ccjm.org/content/78/11_suppl_2/S2.abstract AB