 parathyroid human tumor tissu bone resorpt tissu cultur mous calvaria grown tissu cultur combin singl multipl fragment varieti human tumor glandular tissu determin capac enhanc bone resorpt singl fragment parathyroid adenoma tissu consist enhanc resorpt frontal pariet bone squamou-- cell carcinoma lung activ tissu test singl fragment enhanc hand human tissu enhanc resorpt multipl fragment halo calvarium suggest presenc lesser amount resorpt-enhanc factor human tissu 