The hints are sometimes subtle but they are relentless.

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Still, the results are expected to shed light on the sometimes subtle differences in effectiveness and side effects among various treatments for schizophrenia, a disabling mental illness marked by hallucinations, delusions and numbed emotions.

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Mr. Annan is sometimes a subtle man.

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Another example: Doctors frequently prescribe antibiotics for colds (always caused by viruses) and viral ear infections, sometimes because they feel subtle pressure from patients to prescribe something.

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Sometimes the characteristics are subtle.

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Despite the caricature of her as an "ideologue", she was "one of the most complex" political figures of her age, argued Mr Clegg, and "much of her politics was subtle, pragmatic, sometimes driven by events".

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It may be subtle and hard to see sometimes, but I believe we live in a culture that is often sexist on a day-to-day basis.

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Sometimes the difference between internal versus external payoffs can be quite subtle.

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But when the signs are subtle, it's easy to miss them --sometimes it's even desirable from the point of view of the spouse.

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