Sir - Last week my life was prolonged through the unselfish action of three anonymous blood donors.

As this could have been said on a dozen occasions during the past year, it seemed high time to acknowledge publicly my debt to them and to all the other donors concerned.

Of the many professionals also involved at the John Radcliffe Hospital, I should like to refer to just two groups.

First, the nurses: their considerate care and consistent good humour imbues the whole clinic with a sense of camaraderie - which helps us, the patients, to cope with anxieties and the long hours which transfusions require.

Secondly, there are the technicians, whom we do not see, conscientiously cross-matching blood samples to ensure that no harm comes to the recipients.

To them all let me express, through your columns, a heartfelt, "Thank you".

Tom Fellows, Oxford