title: THE PRESENCE OF A VIRULENCE FACTOR IN M PROTEIN EXTRACTS OF GROUP A STREPTOCOCCI. I. THE ENHANCEMENT OF VIRULENCE OF HOMOLOGOUS STREPTOCOCCI BY THESE EXTRACTS.
mesh_terms: D000486:Allergy and Immunology; D000818:Animals; D001426:Bacterial Proteins; D006224:Cricetinae; D003470:Culture Media; D051379:Mice; D009504:Neutrophils; D010336:Pathology; D010587:Phagocytosis; D012106:Research; D013291:Streptococcus; D013297:Streptococcus pyogenes; D014774:Virulence; D037521:Virulence Factors
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D037521:Virulence Factors
keywords: BACTERIAL PROTEINS; CULTURE MEDIA; EXPERIMENTAL LAB STUDY; HAMSTERS; IMMUNOLOGY; MICE; NEUTROPHILS; PATHOLOGY; PHAGOCYTOSIS; STREPTOCOCCUS