Attempts to grow replacementbone by placing stem cells in a culture chamber of the desired shape have not been very successful, with the cells often dying or producing only weak bone.
Replacement can be a marvelously precise process, so that details of shell ornamentation, tree rings in wood, and delicate structures in bone are accurately preserved.
替换可能是一个令人惊叹的精确过程，因此贝壳纹饰的细节，树木的年轮和骨的微妙结构都被准确地保存。
3
It held great promise for producing replacement skin, cartilage, and bone tissue for burn and accident victims, and nerve tissue to treat spinal cord injuries.