11.   As predicted, in cycle after cycle the capillary-making cells did not develop resistance to the agent.

12.   At least two dozen different kinds of bacteria have developed resistance to one or more antibiotics.

13.   At the same time, increasing numbers of bacteria have developed resistance to antibiotics.

14.   At this time, before the cancerous cells have multiplied enough to develop resistance to chemotherapy, the cancer is much more easily eliminated.

15.   Bacteria can develop resistance to drugs they are frequently exposed to, by random mutations some of which allow the microbes to survive.

16.   Because blood vessel cells, unlike tumor cells, cannot develop resistance to drugs, they offer in principle a far better target for anti-cancer therapy.

17.   Because most patients develop resistance to drugs that fight the virus, experts hope new approaches will help slow the disease progression and eventually overwhelm it.

18.   Because many microbes eventually developed resistance to its antibiotic properties, it has been more or less superseded by other drugs of fungal origin, such as cephalosporin.

19.   Because chickens have been fed fluoroquinolones, the campylobacter bacterium has developed a resistance to that class of antibiotics.

20.   Both of those germs have mutated and developed resistance to medicines, literally under the watchful gaze of researchers.