Polymorphism analysis of Epstein-Barr virus isolates of nasopharyngeal carcinoma biopsies from Tunisian patients. - Ayadi W; Feki L; Khabir A; Boudawara T; Ghorbel A; Charfeddine I; Daoud J; Frikha M; Hammami A; Karray-Hakim H (Virus genes, 2007)