Low ratio of S-adenosylmethionine to S-adenosylhomocysteine is associated with vitamin deficiency in Brazilian pregnant women and newborns - Guerra-Shinohara, Elvira Maria; Morita, Olga Emi; Peres, Sabrina; Pagliusi, Regina Alexandre; Sampaio Neto, Luiz Ferraz de; D'Almeida, Vânia; Irazusta, Silvia Pierre; Allen, Robert H.; Stabler, Sally P. (American Journal of Clinical Nutrition, 2004)