So, if Iraq is concealing something nasty, perhaps only a defector will provide conclusive proof.

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It does not offer conclusive proof that this is causing a rise in asthma.

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There is no conclusive proof that Celebrex works as a preventive drug for anything other than a rare genetic condition that can lead to colorectal cancer.

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After all, there is little conclusive proof that Bigfoot is anything but a myth.

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That's not conclusive proof, but it does look like the boost has a lot to do with the pressure to find something to do when jobs are hard to find.

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Independent reports by military aviation experts, a fatal accident inquiry in Scotland and other investigations had all concluded that there was no conclusive proof of what caused the accident, he said.

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The UUP's Mike Nesbitt said he had examined a report on the horse mussels by Queen's University Belfast and could find no conclusive proof that the problem was caused by any current legal activity.

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