Method: bFGF expression was exmined with immmunohistochemical technique in bud stage,cap stage and bell stage of human tooth germ from aborted embryo of 7,8,10 and 14 weeks.

• 方法 :选择胎龄分别为 7、8、10、14周自愿终止妊娠的新鲜人胚胎各 4例 ,制作牙胚切片 ,将蕾状期、帽状期和钟状期牙胚切片 ,做免疫组化检测。