Explanation: Unit 731 was an infamous Japanese torture unit during WW2 which undertook horrific experiments primarily on Chinese prisoners and civilians. Their results, which were often performed using substandard scientific methodology and record-keeping, often amounted to such stunning conclusions as "If you amputate all of someone's limbs without anesthesia, they usually die".
There was, supposedly, some useful data in more rigorously conducted experiments on frostbite and tuberculosis, but for obvious reasons, there are ethical considerations to the release of that data.