But traditional guidelines say not to use tPA if more than three hours have passed after the first signs of a stroke.

VOA: special.2009.08.12

Breathing in two hundred parts per million of carbon monoxide will cause the first signs of poisoning.

VOA: special.2011.01.25

First,immediately leave the area if you recognize the signs of carbon monoxide poisoning in yourself or others.

VOA: special.2010.02.02

Arick first showed signs of the disease when he was about two years old.

VOA: special.2009.07.28

The first trap shows no signs of oil, only mud stirred up by recent storms.

VOA: standard.2010.05.06

"One of the things we found consistently in the academic literature and elsewhere was that the first responders, state and local law enforcement, did not recognize the signs of human trafficking."

VOA: standard.2010.07.23