Delivery of bone morphogenetic protein-2 by crosslinking heparin to nile tilapia skin collagen for promotion of rat calvaria bone defect repair Lina Ma, Li Fu, Chengxu Gu, Haonan Wang, Zhenghai Yu, Xiuwei Gao, Dongmei Zhao, Baosheng Ge, Naili Zhang*, 10.1007/s40204-022-00213-7 XML