Micro #22

Front 1

Antagonism

Back 1

describing a drug combination that is less effec¬tive than when the drugs are administered alone.

Front 2

Antibiotics

Back 2

chemotherapeutic agents naturally produced by some microorganisms.

Front 3

Broad-spectrum activity drugs

Back 3

drugs that are effective
against a large variety of microorganisms

Front 4

Competitive inhibition

Back 4

describing a situation in which a sub-stance similar to the substrate is competing for the active site of an enzyme.

Front 5

Cross-resistance

Back 5

the phenomenon in which bacteria that are resistant to a particular drug also become resistant to a similar drug.

Front 6

Efficacy

Back 6

the effectiveness of a drug

Front 7

Medium-spectrum activity drugs

Back 7

drugs that are effective against some, but not all, gram-positive and gram-negative bacteria.

Front 8

Minimal bactericidal concentration (MBC)

Back 8

the lowest con-centration of an agent that kills all living organisms in a test tube.

Front 9

Minimal inhibitory concentration (MIC)

Back 9

the lowest concen-tration of an agent that prevents the growth of a selected microorganism.

Front 10

Narrow-spectrum activity drugs

Back 10

drugs that are effective only against a relatively small number of microbes, but that gener¬ally avoid destruction of the normal flora.

Front 11

Selective pressure

Back 11

process by which organisms are forced to adapt or die when exposed to antimicrobial agents.

Front 12

Selective toxicity

Back 12

in which an agent is toxic to the target microorganism but far less toxic to cells of the host

Front 13

Spectrum of activity

Back 13

the range of microorganisms against which an agent is effective

Front 14

Superinfection

Back 14

a secondary infection that occurs when
normal microflora are removed, thus allowing pathogens to
colonize.

Front 15

Synergism

Back 15

the effect produced in a relationship in which two chemicals or organisms work together to produce an effect greater than could have been achieved individually.

Front 16

Therapeutic index

Back 16

ratio comparing the drug dose that pro-duces an undesired toxic effect with the dose that produces a desired positive (therapeutic) effect

Front 17

Zone of inhibition

Back 17

area of no bacterial growth surrounding an antibiotic disk on a Kirby-Bauer plate.