造牙
1.BMP may also be found in human tooth germs, predentin, the cells of outer and inner enamel epithelium, and the cells of dental sac generating alveolar bone.
2.Abstract: Factors causing the failure of the rod string in a screw pump well include rod with minor OD being used，defects in the rod body produced in manufacturing and service，excessive torque caused by plugging and reactive torque on the rod string，and excessive shearing stress on the rod thread.
