High Frequence of Fecal E. Coli Strains Resistents to Beta-Lactamic Antibiotics in Lactents Submitted to Amoxycillin Therapy [Elevada Frequencia De Resistencia Aos Antibioticos Beta-Lactamicos Nas Estirpes Fecais De E. Coli De Lactentes Tratados Com Amoxicilina]
