7/26/2019 Nej m 199304293281701

1/7The New England Journal of Medicine

Downloaded from nejm.org on September 10, 2015. For personal use only. No other uses without permission.Copyright 1993 Massachusetts Medical Society. All rights reserved.

7/26/2019 Nej m 199304293281701

2/7The New England Journal of Medicine

Downloaded from nejm.org on September 10, 2015. For personal use only. No other uses without permission.Copyright 1993 Massachusetts Medical Society. All rights reserved.

7/26/2019 Nej m 199304293281701

3/7The New England Journal of Medicine

Downloaded from nejm.org on September 10, 2015. For personal use only. No other uses without permission.Copyright 1993 Massachusetts Medical Society. All rights reserved.

7/26/2019 Nej m 199304293281701

4/7The New England Journal of Medicine

Downloaded from nejm.org on September 10, 2015. For personal use only. No other uses without permission.Copyright 1993 Massachusetts Medical Society. All rights reserved.

7/26/2019 Nej m 199304293281701

5/7The New England Journal of Medicine

Downloaded from nejm.org on September 10, 2015. For personal use only. No other uses without permission.Copyright 1993 Massachusetts Medical Society. All rights reserved.

7/26/2019 Nej m 199304293281701

6/7The New England Journal of Medicine

Downloaded from nejm.org on September 10, 2015. For personal use only. No other uses without permission.Copyright 1993 Massachusetts Medical Society. All rights reserved.

7/26/2019 Nej m 199304293281701

7/7The New England Journal of Medicine

D l d d f j S b 10 2015 F l l N h i h i i