51.   White blood cells prevent and fight infections.

52.   When they are needed to fight an infection, their risks, of course, are outweighed by their benefits.

53.   When used for burns, aloe also helps prevent swelling, repair damaged cells, fight infection and prevent scarring, according to the American Botanical Council.

54.   Wiley, an expert on how the immune system fights infections, had recently studied other infectious diseases including AIDS, herpes, and influenza.

55.   White blood cells, a critical component of the immune system, help fight infections.

56.   With leukemia, a cancer of the blood and bone marrow, abnormal white blood cells crowd out healthy white cells, which help fight infections.

57.   Young people get the flu more often, but older ones suffer most from its complications because of their reduced resistance and inability to fight infection.

58.   A follow-up visit found her T-cell count, the white blood cells crucial to fighting infections, at a healthily high level.

59.   A medical statement issued by the Onassis Cardiac Surgery Center said that doctors had tailored a cocktail of antibiotics to try and fight the infection.

60.   And Buck was at a dolphin research center, fighting an infection.