I have tried to visit the PubMed site www.nlm.nih.gov but receive the message that I am not authorised to view the page. Has anyone else had difficulty getting on to this site? Ian Holbrook Department of Chemical Pathology York District Hospital Wigginton Road YORK YO31 8HE UK _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp