Original sentence: As more research yields increasingly precise techniques, stem cell transplantation to restore vision may become viable on a large The success rate of the procedure is currently from 20 to 70 percent , and further clinical research is intensely required before any credible claim can be made
Edited sentence: As more research yields increasingly precise techniques, stem cell transplantation to restore vision may become viable on a large scale.However, the success rate of the procedure is still low, from 20 to 70 percent , and further clinical research is intensely required before any credible claim can be made