[Doctor]
Well, I can tell you right now, I am not letting him recreate anything even close to the immortality gate unless we want to see the Master race marching around earth... Even then, we wouldn't see it, because he'd be us.
Repair... Repair... NANOGENS! Doctor, I have nanogens!
... But they're programmed to human anatomy, I don't know what they'd do to a Time Lord. They could repair him, in theory, but they might remove one of his hearts. They might change everything about him... The results would, of course, have to be stable, to a point, but he might not even be himself... I'm not sure how good of an idea that is, he might end up even less on the sane side than we left him...
And no, I won't let anyone get hurt. I don't want to kill him, he's the only other like you, and I couldn't do that. I'd rather him try to eat me before anyone else. At least I'll come back.