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Albert R. Allen, M.D.; Elizabeth A. Roberg, B.S.
JAMA. 1955;159(16):1533-1534. doi:10.1001/jama.1955.02960330033010b.
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The emergence of tubercle bacilli that are resistant to any antibiotic is an adaptation occurring spontaneously as a result of selective mutation for survival. This phenomenon occurs in the laboratory and seems to occur also in patients. Its occurrence is related to the size of the original organism population and the concentration of the drug or drugs, but there must be bacterial multiplication for this selective mutation to occur. Loss of resistance is reported in a few strains resistance to 10 mg. per cubic centimeter of streptomycin after many months per cubic centimeter of streptomycin after many months (22 to 42), with 10 to 21 transplants, but organisms resistant to high concentrations of streptomycin, 100 mg. per cubic centimeter, maintain this resistant characteristic. Courmont and others - found coexistence of bacilli sensitive and resistant to streptomycin in sputum, and Canetti and Saenz, along with Medlar and others, found variance in


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