PT - JOURNAL ARTICLE AU - Carol Black TI - Spheres of medical influence AID - 10.7861/clinmedicine.6-4-387 DP - 2006 Jul 01 TA - Clinical Medicine PG - 387--391 VI - 6 IP - 4 4099 - http://www.rcpjournals.org/content/6/4/387.short 4100 - http://www.rcpjournals.org/content/6/4/387.full SO - Clin Med2006 Jul 01; 6