These are useful drugs and they have their place.

Scientists hope that they will discover useful new drugs and pesticides.

"You could design a molecular structure, which has a potential to become a useful drug," he said.

However, this is an extremely rare side effect of a useful drug.

Kept away from developing fetuses it can be an extremely useful drug.

The patients have long pleaded for quicker access to a wider range of potentially useful drugs.

So it was, and a most useful drug too.

But whether they would produce many more useful drugs is problematic, some officials said.

If the donations are no good, that is money that could have been spent on more useful drugs.

He added that with broader screening "we probably would have picked up several useful drugs."