31.   If it can be shown that blood flows freely into the heart even under stress, then it may not be necessary to bypass even seriously blocked arteries.

32.   In the syndrome not enough blood can flow to nourish the heart because the coronary arteries are blocked by fatty deposits from the underlying condition, atherosclerosis.

33.   It works within an hour, relaxing smooth muscles in the penis so blood can flow into the spongy tissue that becomes engorged to cause an erection.

34.   It works by allowing more blood to flow to the genital area, but has been tested only in men.

35.   Most of us see homicide as a huge problem, but the blood is not flowing fast enough to suit the firearms industry.

36.   Normally the blood vessels would dilate to allow more blood to flow back to the lower arm.

37.   Nitric oxide is an important chemical messenger that signals blood vessels to relax and allow blood to flow more freely.

38.   Once in a while, the crewmen released the rubber tube, allow blood to flow into his arm for a minute or so.

39.   Prick him, and green blood will flow.

40.   Sol players, for example, are tested for Mitral Valve Prolapse, a kind of regurgitation in which the blood flows backward.