Primary gram negative pneumonias.
D001442:Bacteroides Infections / Q000453:epidemiology*; D004756:Enterobacteriaceae Infections / Q000453:epidemiology*; D005260:Female; D006192:Haemophilus Infections / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008824:Michigan; D008875:Middle Aged; D011014:Pneumonia / Q000453:epidemiology / Q000209:etiology*; D011552:Pseudomonas Infections / Q000453:epidemiology*