Sanhedrin 59: Not the Sciatic Nerve or a Limb from a Live Animal

More on the Noahide laws -- eating the limb from a live animal, in contrast to the Jews being prohibited about the same thing. But why wasn't the one prohibition sufficient to teach them both? The Gemara says that the Noahide commandments were not repeated at Sinai (except for when and why they were). Yet nothing that is permitted for Israel is prohibited for Bnei Noah - except for "eshet yifat to'ar," some discussion over small thefts, and circumcision. Also, the shift to eating meat that was only permitted in the era of the Bnei Noah, and not the time of Adam, or the beginnings of humanity.