41.   These resistant strains replace the normal bugs, and they also can pass their traits to other microbes.

42.   They say they cannot pay for needed trips to Italy or Russia to examine resistant strains of honeybees.

43.   This could happen, she said, if HIV-infected individuals could obtain only the cheaper two-drug regimens certain to give rise to resistant strains.

44.   This year, though, a resistant strain of the fungus emerged, and by mid-August, growers throughout the valley were reporting blue mold in their fields.

45.   Thus, drug treatment can lead to the emergence of resistant strains.

46.   Twenty percent of the chickens had a resistant strain.

47.   Tuberculosis strains resistant to drugs are increasing and the downward trend of reported cases of the disease in western Europe has leveled off.

48.   Under such circumstances, resistant strains could be transmitted to others.

49.   But resistant strains have become a growing problem blamed in part on the overuse of antibiotics.

50.   Dangerous TB strains resistant to several drugs often evolve in such patients.