The New England Journal of Medicine Downloaded from nejm.org at BIBLIOTHEQUE UNIV LAVAL SEC ACQ on November 20, 2015. For personal use only. No other uses without permission. Copyright © 1991 Massachusetts Medical Society. All rights reserved.
The New England Journal of Medicine Downloaded from nejm.org at BIBLIOTHEQUE UNIV LAVAL SEC ACQ on November 20, 2015. For personal use only. No other uses without permission. Copyright © 1991 Massachusetts Medical Society. All rights reserved.
The New England Journal of Medicine Downloaded from nejm.org at BIBLIOTHEQUE UNIV LAVAL SEC ACQ on November 20, 2015. For personal use only. No other uses without permission. Copyright © 1991 Massachusetts Medical Society. All rights reserved.
