But relaxation techniques may not be enough, Peeke said, since the best way to block stress hormones is through beta endorphin -- produced during exercise.

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Other companies, such as Neurogen, Aventis and Neurocrine Biosciences, are in early tests of drugs that block a damaging stress hormone often elevated in depressed patients.

FORBES: Think Happy

For another, the strategy of UK ministers is to highlight uncertainty, not to seem to be suggesting that they are placing any block in the path of a decision which, they repeatedly stress, is one for Scotland to take.

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