Submitted on: 19 October 1999.
Revised on: 28 January 2000.
Accepted on: 07 March 2000.
___________________Annals of Cardiothoracic Surgery
Submitted on: 06 October 2008.
Revised on: 10 November 2008.
Accepted on: 15 December 2008.
___________________Annals of Cardiothoracic Surgery
Submitted on: 13 December 2002.
Revised on: 27 January 2003.
Accepted on: 18 March 2003.
___________________Annals of Cardiothoracic Surgery
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