RT Journal Article SR Electronic T1 Abstracts JF The British Journal of Venereal Diseases JO Br J Vener Dis FD BMJ Publishing Group Ltd SP 229 OP 232 DO 10.1136/sti.41.3.229 VO 41 IS 3 YR 1965 UL http://sti.bmj.com/content/41/3/229.abstract AB