61.   Doctors knew that in some of those patients the disease would grow and spread, or metastasize, whereas in others it would not.

62.   Doctors know that a low pregnancy rate can spell doom for their clinic.

63.   Doctors know that the sharp curbs on malpractice lawsuits that Mr. Gingrich favors face a tough future in the Senate.

64.   Doctors know they are battling bigger issues than simply urging young patients to have willpower.

65.   Doctors now know that a combination of three or more drugs is the most effective treatment for HIV.

66.   Dr. Jeffrey Nichols, who is treating Taylor at Grady, said it could be weeks before doctors know if she will recover fully.

67.   Even your doctor knows better than to call it the flu.

68.   For decades, doctors have known that bone marrow transplants, though potentially lifesaving, also raise the risk of leukemia and bone marrow disorders later on.

69.   For years, American doctors have known that the technique works with no serious side effects, and many have quietly recommended it to plenty of panicked women.

70.   For years, doctors have not known which is the better way to take the beta-agonist drug albuterol, also sold as Proventil and Ventolin.