"An X-ray taken immediately after John left the field did not show the injury, " added English.

BBC: Terry may miss England friendly

There are, however, no interference problems with field-emission X-ray sources, so these can be used to take high-resolution pictures while treatment is proceeding.

ECONOMIST: Modern X-ray technology

His first company--launched in his mid 20s--made software for X-ray imaging machines and, later, for laptop computers that helped field technicians troubleshoot glitches in large equipment made by the likes of Xerox and Siemens.

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His first company--launched in his mid 20s--made software for X-ray imaging machines and, later, for laptop computers that helped field technicians troubleshoot glitches in large equipment made by the likes of Xerox (nyse: XRX - news - people ) and Siemens.

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