In exchange, Brownback backed off amendments that would have banned human cloning and prohibited creating animal-human hybrid embryos.

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But Ditmire from Fox-Pitt Kelton says the so-called hybrid half-human, half-electronic system at NYSE "is at a relative disadvantage" on days like Thursday.

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But the 2009 H1N1 virus is a hybrid of swine, avian and human strains, and no vaccine has been developed for it.

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The virus, a hybrid of swine, avian and human flu, can jump from person to person with relative ease.

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