Complex sentence: He used from 20 to 75 or 100 bee stings per patient, from bees he bred in his own hives outside his office specially for the purpose, but stated that arthritic patients were almost immune to the pain of the sting.
Split into simpler sentences: He used from 20 to 75 or 100 bee stings per patient, from bees bred in his own hives outside his office specially for the purpose. He opined stated that arthritic patients were almost immune to the pain of the sting.