Objective: To study expression of whether Shh and its receptor Ptc during late bell stage in mouse tooth germ.

• 目的 :判断sonichedgehog(Shh)基因及其受体patched(Ptc)是否在小鼠牙胚钟状晚期有表达。 方法 :用RT PCR法研究Shh及其受体Ptc在小鼠牙胚钟状晚期的表达。