There are interesting data on hypothermia based on Nazi human experimentation, which are especially interesting because it's impossible to replicate these measurements for obvious reasons. The ethics of using and citing those have been a matter of controversy for decades:
http://www.pbs.org/wgbh/nova/holocaust/experi02_no.html

Otherwise, however, the human experiments done by Nazi doctors seem to have been scientifically worthless. Mengele in particular was just a particularly cruel dilettante.