FIG. 4. Two frontal sections through the fore-limb buds of mouse embryos, at the level of an interdigital zone. UnnaBrachet's technique for ribonucleic acid, (a) 12\-day. Beginning of degenerative phenomena in the interdigital outer
mesoderm as revealed by the presence of R N A a n d DNA droplets in the cytoplasm of the degenerating cells, (b) 14-day.
Extension of degenerative phenomena to more proximal cell layers (arrow).
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mesoderm as revealed by the presence of R N A a n d DNA droplets in the cytoplasm of the degenerating cells, (b) 14-day.
Extension of degenerative phenomena to more proximal cell layers (arrow).
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