Fine structure of the apical rim-mesenchyme complex during limb morphogenesis in man.
نویسنده
چکیده
Ultrastructure of the apical rim-basal lamina-mesenchyme complex in man during Horizons 15-18 is correlated with the development of limbs. 1. Apical epithelium is a complicated tissue exhibiting surface microvilli, junctional complexes, free ribosomes, elaborate Golgi centers, glycogen and scanty granular endoplasmic reticulum. 2. The apical rim thickens during stages 15 and 16, remaining multilayered at digital tips and thinning adjacent to zones of necrosis by stages 17 and 18. Epithelial thinning may be a response to lack of 'maintenance factor'. 3. A continuous basal lamina is present during these stages. Collagen-like fibrils are numerous in interdigital zones of necrosis and sparse at tips of digital blastemata. 4. The presence of oriented microfilaments in interdigital epithelium suggests active invagination during morphogenesis of fingers in man.
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عنوان ژورنال:
- Journal of embryology and experimental morphology
دوره 29 1 شماره
صفحات -
تاریخ انتشار 1973