Apud concept: Hypothesis or tautology?

This publication has 7 references indexed in Scilit:

• 4 Brain and gut
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• A Review of “Chromaffin, Enterochromaffin and Related Cells, ” with Some Comments on the APUD and Paraneuron Concepts
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• NEUROENDOCRINE EMBRYOLOGY AND THE APUD CONCEPT
  Clinical Endocrinology, 1976
• The Neural Crest and the Origin of the Insulin-Producing and Other Gastrointestinal Hormone-Producing Cells
  Science, 1976
• Neurocristopathy, neuroendocrine pathology and the APUD concept
  Zeitschrift für Krebsforschung und Klinische Onkologie, 1975
• Neural crest origin of the endocrine polypeptide (APUD) cells of the gastrointestinal tract and pancreas
  Gut, 1971
• Common cytochemical properties of cells producing polypeptide hormones, with particular reference to calcitonin and the thyroid C cells
  Published by Wiley ,1966