The human environmental studies would include things such as the population in a country, how a country's economy is doing, and more.

These problems, however, have not been seen in human studies, though it may be too soon to tell.

The responses were similar to those reported from human studies.

Whether the same thing could happen in humans is not known, however, because only a few human studies have been done.

Few, if any, human or animal studies have been done.

This human study, he said, is in strong agreement with the animal research.

And for every five drugs that get into human clinical studies, only one ever makes it to market.

As for the human studies, they are contradictory and open to various interpretations.

As documents and human studies, the images are nothing short of fascinating.

But some human studies indicate that tea may protect against cancer.