Well replacing all organs save for the brain certainly would do the trick, since the brain is the cause of death in 0.001% of cases.
The body is the one which is weak.
And as for nanotechnology, there's nothing that proves it exists, and nothing that proves it doesn't. It seems logical it would, though, since even in our time right now research for medical applications of nanotechnology is in progress.
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<span style="color:#000000">All morons hate it when you call them a moron.
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