It was concluded that the cartilage canals of fetus play great roles in formation of secondaryossificationcenter and exist in primary secondaryossificationcenter.
说明胎儿股骨远端次级骨化中心初始时其内存在软骨管，软骨管对次级骨化中心的形成起作用。
2
To observe the correlativity between secondaryossificationcenter and cartilage canals in cartilage epiphysis and the initial morphosis of the secondaryossificationcenter.
为观察软骨骺内次级骨化中心与软骨管的关系，及次级骨化中心初始形态结构。
3
At the distal part of femur in fetus age of 30 weeks, a cluster of lump-like osteogenic cell, osteoblast and basophlous osteoid filled among cells appeared at the secondaryossificationcenter.