41.   The notion that antibiotic treatment may keep a nonspecific upper respiratory tract infection from getting worse.

42.   The product, called FluMist by Aviron is prepared from live flu viruses modified to survive only in the nasal passages, not in the lower respiratory tract.

43.   These infections gain a foothold when the cold symptoms weaken defenses and impair drainage in the respiratory tract.

44.   They include polyoxyethyleneamines, which irritate the respiratory tract, eyes and skin, and a byproduct, dioxane, a suspected carcinogen.

45.   When this happens during sleep, some of the regurgitated acidic material may be inhaled into the respiratory tract, causing coughing, asthmatic symptoms or even pneumonia.

46.   When the virus enters the body of the first, it homes in on certain structures in her respiratory tract.

47.   A common bacterium that causes respiratory tract infections has evolved into a killer bug that antibiotics cannot fight in Singapore, a newspaper reported Tuesday.

48.   A common bacterium that causes respiratory tract infections has evolved into a killer bug that antibiotics cannot fight in Singapore, doctors and news reports said Tuesday.

49.   Air pollution contributes to lung disease, including respiratory tract infections, asthma and lung cancer.

50.   Avelox is used for treatment of respiratory tract infections and community-acquired pneumonia.