31.   The decision is motivated in part by fears that transplanting animal organs into people could unleash deadly new viruses among the human population.

32.   The idea of using animal organs for transplant, known as xenotransplantation, is controversial because some believe illnesses could cross from pigs to humans.

33.   The industry is exploring ways of altering genes to create, for example, lifesaving medicines, pest-resistent foods and animal organs suitable for human transplantation.

34.   The machine had already been tested using a human kidney and animal organs.

35.   Tiger bones, rhino horns and animal organs are in great demand in Asia and are used in traditional Chinese medicines for treating sexual problems.

36.   Transplanting animal organs into humans offers such promise that nations should work together to overcome scientific and ethical problems, experts told a U.N.-sponsored meeting Thursday.

37.   Transplanting animal organs into humans offers such promise that nations should work together to overcome scientific and ethical problems, experts said at a U.N.-sponsored meeting.

38.   Transplanting animal organs into humans has failed to work in the past, but Platt and his colleagues have used genetic manipulation to improve their chances for success.