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Submitted on: 15 March 2013.
Revised on: 26 April 2013.
Accepted on: 03 June 2013.
___________________BMC Geriatrics---BMC
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Submitted on: 30 November 2013.
Revised on: 09 February 2014.
Accepted on: 14 March 2014.
___________________BMC Geriatrics---BMC
Submitted on: 05 January 2010.
Revised on: 21 March 2010.
Accepted on: 02 April 2010.
___________________BMC Geriatrics---BMC
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