41.   Although the work only has been demonstrated in laboratory animals, Petersen said other studies strongly suggest humans also have bone marrow cells that will convert into liver cells.

42.   But a team of researchers led by Stephen C. Strom of the University of Pittsburgh discovered that human liver cells exposed to the compound in lab tests were killed.

43.   Doctors found that the women who got bone marrow transplants from men had some Y-chromosome liver cells.

44.   He tested human liver cells infected with hepatitis to see if they were sensitive to the drug.

45.   Human liver failure often involves a virus or a toxin that may persist even after the liver cells are transplanted, he said.

46.   Researchers could analyze the livers of the test subjects to see where the liver cells were coming from.

47.   Roche say it is likely most cases of liver cell injury can be prevented by attention to patient symptoms.

48.   So Strom and his team did a control experiment using healthy human liver cells.

49.   The men, who got liver transplants from female donors, also had Y-chromosome liver cells on their female livers.

50.   The liver often can generate new hepatocytes, or a type of healthy liver cells, after an injury or disease.