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

Professor Hess says a major value of sustainable agriculture is making good use of what you have.

VOA: special.2009.04.14

But you have to use a safe method or you could do a lot of damage.

VOA: special.2010.03.31

Have you ever agreed to the "terms of use" for a service without reading it all?

VOA: special.2010.04.30

"One of the challenges we have is to make the Web a lot easier to use even on the simplest and least expensive mobile phones."

VOA: special.2010.11.08

The first involves sheep. Researchers have found that hair sheep are a good source of blood for use in tests to diagnose infectious diseases in people.

VOA: special.2009.08.03

Belladonna and other poison plants have a long history of medical use.

VOA: special.2009.08.25

"The military commissions have been reformed by the Congress and the Obama administration in a way that prohibits absolutely the use of any evidence obtained through torture or cruelty."

VOA: special.2010.11.20

"So if you have hoarseness with tobacco or alcohol use, that would be a significant risk factor for cancer or other problems of the throat that could be serious.

VOA: special.2009.09.02

So,yes,there is a threat particularly of the use of radioactive material, although we have no specific evidence indicating any capability at this time."

VOA: standard.2009.05.01

It's a country more like the mountainous parts of Afghanistan, where you have to undertake special operations, more use of the air (power) and, also,political handling.

VOA: standard.2009.06.18

Bereket told reporters, pro-government Somali militias have permission to use Ethiopia as a base of operations in attacking al-Shabab rebels, who control large sections of southern Somalia.

VOA: standard.2009.08.20

"we don't have money to buy insecticide, the little money we have, we use to take care of the kids, we don't have a lot of money."

VOA: standard.2010.03.30

you have to assume they are in," He says the more advanced a country is in its use of computers and the Internet, the more vulnerable it may be.

VOA: standard.2009.08.11