21.   In fact, scientists have identified at least two other outlier HIV strains and are temporarily calling them Type O, although they are very dissimilar.

22.   It was one of the first bacteria that scientists identified as a killer.

23.   Levels of these toxins might also be reduced, Silverberg hopes, even if scientists never identify just what the toxins are and how they function.

24.   Modern technology allows scientists to identify such minute traces of chemicals that a zero-tolerance law is outdated, Bliley continued.

25.   Mullis was honored for inventing a technique allowing scientists to identify even a fragment of DNA and reproduce it.

26.   Now scientists have identified a key difference in how humans and the malaria-causing parasite Plasmodium regulate a single enzyme.

27.   Now, as the field of immunology has flowered, scientists have identified several cells that act in concert to reject foreign cells.

28.   Now scientists have identified a taste receptor that may play a part in making sure we consume enough of it.

29.   Only analysis and debate will determine whether scientists have identified ancient traces of life on Mars.

30.   Other scientists had identified a type of white blood cell known as T cells as responsible for producing graft-versus-host disease.