You have done all the right things, so it could be due to a resistant strain of the yeast that causes thrush.

All patients have been tested and those with the resistant strain have been given other antivirals.

And as they become sicker, they become more contagious and spread the resistant strain.

They found that almost 50 genes were turned on in the hippocampus of the resistant strain vs. only a dozen in the sensitive strain.

They suggest the emergence of a resistant strain may be associated with a patient's clinical deterioration.

The resistant variety has been like the widespread version of the virus in that it typically produces only mild symptoms.

In addition, the suppliers didn't believe a resistant variety could be produced.

With this development, the townspeople built a new park, planted with the new resistant variety.

It makes sense to try these resistant varieties to see if they are as good as they say they are.

Are there any resistant varieties?

But many readers are proving stubbornly resistant to the allure of the ebook, preferring well-thumbed pages to touchscreens, and crammed bookshelves to waning battery power.

Airlines have proved stubbornly resistant to the pannational mergers that have swept through other global industries.

Similar treatments are also being developed for bacterial ear infections and food poisoning, which are triggered by the most stubbornly resistant bugs.

But ironing has remained stubbornly resistant to mechanisation.

The human heart remains stubbornly resistant to total replacement, its physical mysteries nearly as challenging as the metaphorical ones that have plagued us since the beginning of time.