RT Journal Article SR Electronic T1 Clopidogrel reduced recurrent ischaemic events in patients with previous cardiac surgery more than aspirin JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 114 OP 114 DO 10.1136/ebm.6.4.114 VO 6 IS 4 YR 2001 UL http://ebm.bmj.com/content/6/4/114.abstract AB