人胎儿真皮乳头和皮纹发生的研究

本文用扫描电镜法研究了入胎儿的皮纹发生过程,包括初级真皮嵴、次级真皮嵴、真皮乳头和表皮隆线的发生。为研究人皮纹的发生和皮肤的异常提供了皮肤正常发育的形态学依据。共观察111例从第6周到第9个月胎儿的皮纹区皮肤,表明第3个月末胎儿开始形成初级真皮嵴,以后逐渐加深,至第16周嵴的顶端中央产生纵沟形成两条平行的次级真皮嵴;自19周后,次级真皮嵴局部隆起,由波浪形逐渐形成乳头。至30周乳头呈犬牙状。表皮隆线于第4—5月形成,随真皮乳头的增高而渐趋明显。至第6个月,全部皮纹图样已可辨认。本文还讨论了真皮乳头发生的过程。

ON THE DEVELOPMENT OF DERMAL PAPILLAE AND EPIDERMAL RIDGES OF HUMAN SKIN

The formation of the primary dermal ledges, secondary dermal ledges, dermal papillae and epidermal ridges were observed with scanning electron microscope. The volar skin of 111 samples including embryos of 6th week to fetuses of 9th month were prepared. The distal phalanges and digites, palms and soles of freshly aborted embryos and fetuses were prepared by routine methods. Some of them were pretreated with ammonium thiocyanate to remove the epidermal layer for observation on the dermal surface. In the 6th week embryos, the body surface was covered by a layer of periderm. Each peridermal cell has many tiny microvilli and a large central vacuole projecting from the cell surface. In the third month fetuses, the primary dermal ledges and grooves gradually appeared, but the epidermal surface showed noepidermal ridges. The primary dermal ledges began.to divide into double parallel ledges,-the secondary dermal ledges in the 16th week fetuses. Concomitantly, a furrow was recognizable between the two related secondary dermal ledges. The dermal papillae first appeared in 19th week fetuses and then elevated gradually to form zigzag shape in 30th week. The epidermal ridges appeared simultaneously with the secondary dermal ledges in 4th to 5th month and the dermatoglyphic configurations were recognizable in 6th month fetuses. The embryogenesis and the relationship between the dermatoglyphic configuration on the skin surface and the dermal ledges and dermal papillae were discussed.