31.   In an experiment that could point the way to a new approach to fighting cancer, scientists blocked the enzyme that most forms of cancer need to continue growing.

32.   Like other blood pressure drugs, Vanlev blocks enzymes that constrict arteries and thicken their walls, but it also increases levels of a chemical that dilates blood vessels.

33.   Several of the drugs that failed early testing were designed to block an enzyme the cancer needs to eat out channels for new blood vessels.

34.   Statin drugs work by blocking an enzyme that helps to make cholesterol in the liver.

35.   Statins block an enzyme needed to make cholesterol in the liver.

36.   Some block the enzymes that are necessary for new blood vessels to burrow through surrounding tissue.

37.   The drug works by blocking an enzyme known as a protease, which is essential for the virus to replicate.