[Thyroid antagonists. X. Action of the methylene ether of 4-methyl-6-oxo-2-thio-5-pyrimidinol, of the methylene ether of 5-ethyl-4-methyl-2-thiouracil, of 5-ethyl-4-methyl-2-thiouracil, and of the methylene ether of 4,5-dimethyl-2-thiouracil on the weight curve, oxygen consumption and thyroid and pituitary histological pictures after parenteral administration to rats].