They may have a weak or damaged heart, high blood pressure or other problems of the blood system.

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After six Eurostar trains broke down in or near the tunnel that runs under the English Channel, the system has been suspended while engineers troubleshoot the electrical problems thought to have been brought on by condensation.

VOA: standard.2009.12.21

Moreover, he says, the trial excluded patients at high risk for bleeding, such as those with central nervous system tumors or vascular problems.

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Of the 241 cases reported so far this year, 144 were severe cases in which the virus spread to the brain and nervous system and caused encephalitis or other problems.

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Apple remains a closed system with its fair share or problems.

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