英语语法分析

At present time the basic research of xenogeneic transplantation should be mainly emphasized.

目前应进一步加强异种器官移植的基础研究。

Objective To prepare the xenogeneic acellular nerve scaffold used a modified chemical extraction method.

目的用改良的化学萃取方法，制备去细胞异种神经支架。

Objective: To evaluate the osteogenesis of xenogeneic bone derived materials in repairing segmental bone defects.

目的：评价三种异种骨衍生材料修复节段性骨缺损的成骨作用。