Jejunoileal BypassHyperlipidemiasOsteoporosisOsteoporosis, PostmenopausalBone DensityCalcium SignalingBone Density Conservation AgentsCalcium, DietaryFractures, BoneCalcium ChannelsOsteoporotic FracturesDiphosphonatesAbsorptiometry, PhotonBone and BonesAlendronateFractures, SpontaneousBone Diseases, MetabolicCalcium CarbonateTeriparatideCalcium IsotopesEtidronic AcidSpinal FracturesBone ResorptionCalcium PhosphatesBone RemodelingFemur NeckCalcium ChlorideLumbar Vertebrae