SF book... can't remember title or author

[koldflame]

This book was interesting and I really want to read it again. However, I read it a few years ago and can't remember title or author... I've been racking my brain for weeks trying to remember and I still can't so I hope one of you can.

If I remember correctly, this guy was abducted by aliens, who when they examined him determined that the human body was very inefficient. They changed it to be more efficient and then released him back to earth. As a result of this changing, he can control his body with his mind, such as creating multiple hearts or regrowing organs he had lost. He can also capture (or "wall off") any foreign substances in his body and examine them to determine what they do or if they would harm him.

Its an older book I think (as in before the 90's) although I can't really remember. Any help would be greatly appreciated.

Thanks in advance,
-Steven Cohen

 

[letterHead]

It sounds a bit like Thorns, by Robert Silverberg, although I don't remember the regrowing of organs. Healer, by Paul F Wilson, does have that ability, but his comes from an alien symbiote.

 

[koldflame]

Thanks for your reply! I've looked at the descriptions of the two books you mentioned and I don't think either one is the book I'm looking for. But I won't know for sure until I find a copy to look at.