中文摘要：

目的探讨大鼠胚胎背部皮肤β-NGF和p75NTR的表达规律。方法使用冰冻超薄切片结合免疫组织化学染色方法和显色半定量统计方法。结果大鼠胚胎背部皮肤呈现逐渐增厚的趋势，其中毛囊隆突区并不明显，但可明显观察到基底层细胞的表达变化。结论形态学观察说明毛囊发生初期毛囊于细胞（hair follicle stem cell，HFSC）不仅仅定位于毛囊上段β-NGF和p75NTR的表达有差异。背部皮肤基底层细胞具有于细胞特性，未分化为表皮细胞或者毛囊中的各种细胞。β-NGF和p75NTR的表达变化可能与毛囊于细胞以及毛囊的生物学特性有关。

英文摘要：

Objective To detect the expression of β-NGF and p75NTR in developmental rat embryo dorsal skin. Methods Using frozen section and Immunohistochemistry to investigate the expression of β-NGF and p75NTR. All the data was summarized by semi-quantification. Results Embryo dorsal skin became thicker gradually without bulge region significant, but the expression of β-NGF and p75NTR in basal cells changed obviously. Conclusion the results of morphology suggest that hair follicle stem cells （HFSCs） not only located in upper-hair follicle in early stage of hair follicle morphogenesis. Especially, basal layer cells in dorsal skin exhibited stem cell characteristics without differentiating into epithelial cells or other type of cells in hair follicle. The expression of β-NGF and p75NTR may be correlated with characteristics of hair follicle and hair follicle stem cells.