11.   Petersen said that his research investigated how some people with liver failures are able to grow new liver tissue.

12.   Blood is cleaned as it goes through the tubes, and chemicals from the blood pass back and forth through the fabric to the liver tissue.

13.   But Petersen said that some patients who do not make new hepatocytes still end up growing new liver tissue and recovering.

14.   Sanson said extensive samples of whale tissue, liver tissue and teeth had been removed from the whales for investigation by marine scientists.