And as professor Von Heijne says, their understanding of the mechanisms at work has opened the door to others seeking new treatments.

VOA: standard.2009.10.07

House Speaker Pelosi agreed, saying Congress and the Obama administration must keep the door open to additional steps, even as the current stimulus plan begins to work.

VOA: standard.2009.03.10

If you don't like the way I work here,there's the door.

VOA: standard.2009.12.17