படிமம்:Gram stain 01.jpgSpanish microscopic image of a Gram stain of mixed Gram-positive cocci (Staphylococcus aureus ATCC 25923, purple) and Gram-negative bacilli (Escherichia coli
படிமம்:Bordetella pertussis.jpgMikroskopisches Bild von Bordetella pertussis, dem Erreger von Keuchhusten, nach Gram-färbung applies to jurisdiction: United States of America determination method