TY - RPRT TI - Morphological differences in Xenopus embryonic mesodermal cells are specified as an early response to distinct threshold concentrations of activin. AU - K Symes AU - C Yordán AU - M Mercola PY - 1994 DO - 10.1242/dev.120.8.2339 UR - https://pubmed.ncbi.nlm.nih.gov/7925034/ ID - 7925034 ER -