mouse iodinated epidermal growth factor ( egf ) was localized by light and electron microscopic radioautography in basal cells of oral epithelium , papillary cells of the enamel organ , periodontal ligament fibroblasts , preodontoblast precursor cells , and preosteoblasts of the alveolar bone of 13-day-old sprague-dawley rats .
C0007634
cells
C0018956
precursor cells