So far scientists at five laboratories have failed to identify any known infectious agent as its cause.

She can't seem to pin down the coma to any known agent and she's getting frustrated.

After, they tested resveratrol in combination with several different known anticancer agents.

You are a known agent of a foreign power.

In terms of mortality, the former is second only to smoking among known agents causing cancer.

"A good, known agent gets stuff to the top of the pile; their chief ability is getting something read."

The cause of pingueculitis is unknown but there are no known infectious agents associated with its manifestation.

Perhaps the service might want to continue running the known redoubled agent in order to conceal other operations.

We must keep all known agents of Trantor under strict scrutiny without really interfering with them.

I looked for every known agent that affects cardiac rhythm.