title: [Ecological study on the pathogenic bacteria in pre-clinical chronic lower respiratory tract infections].
mesh_terms: D000328:Adult; D000368:Aged; D002908:Chronic Disease; D005260:Female; D006193:Haemophilus influenzae / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D012141:Respiratory Tract Infections / Q000382:microbiology*; D013183:Sputum / Q000382:microbiology; D013211:Staphylococcus aureus / Q000302:isolation & purification; D013296:Streptococcus pneumoniae / Q000302:isolation & purification