41.   Skeletal muscle cells, said Dr. Marco Pahor, chief of geriatric medicine at Wake Forest, have receptors for angiotensin.

42.   Some athletes never feel completely healed, because fibroblasts flourish, more so than muscle cells.

43.   Special tight connections between all heart muscle cells let the electrical charge flow through at pretty much at the same instant.

44.   Such cells apparently have the potential to develop into most of the specialized cells and tissues of the body, including muscle cells, nerve cells and blood cells.

45.   Tests showed that what seemed to have been dead heart muscle began contracting, hinting that the thigh muscle cells were now functioning as heart muscle.

46.   That meant there was nothing to stop the muscle cells from growing quickly into an artery-blocking mass.

47.   The balloon scrapes off the lining of the artery, leaving a raw surface and exposing the smooth- muscle cells underneath.

48.   The body stores creatine in muscle, nerve and sperm cells and provides muscle cells with energy.

49.   The clots stop the flow of blood carrying oxygen and other nutrients, leading to death of heart muscle cells.

50.   The correct form of the gene had been injected into their muscle cells.