11.   Very recent research has demonstrated that if these inhibitory proteins are blocked, severed nerves can regrow, and that adding certain growth factors fosters that regeneration.

12.   But scientists might someday develop a pill to block the protein the gene produces, which would keep patients from accumulating more iron, Andrews said.

13.   Called nucleoside analogs, they work by blocking a protein active in the early reproduction cycle of the virus, but the virus quickly develops resistance to their effect.

14.   Experiments in rats showed that when the protein is blocked, the spinal cord can repair itself.

15.   Researchers also say they may be able to develop a drug to block the protein once they better understand the function and location of proteins in specific tissue.

16.   Researchers were able to delay the onset of a form of mad cow disease by blocking a protein that usually assists the immune system.