_:vb50947824 . _:vb50947824 . _:vb50947824 . _:vb50947824 "url:http://www.mayoclinic.com/health/osteoporosis/DS00128"^^ . _:vb50947824 "A bone resorption disease characterized by decreased density of normally mineralized bone which results_in the thinning of bone tissue and decreased mechanical strength."^^ . _:vb50947824 "url:http://www.nlm.nih.gov/medlineplus/ency/article/000360.htm"^^ . _:vb50947824 . _:vb50947824 "url:http://en.wikipedia.org/wiki/Osteoporosis"^^ . _:vb50947824 . _:vb50947824 "url:http://www.niams.nih.gov/Health_Info/Bone/default.asp"^^ . _:vb50947824 . _:vb50947824 .