Submitted on: 23 June 2006.
Revised on: 26 September 2006.
Accepted on: 29 October 2006.
___________________JOURNAL OF OCCUPATIONAL HEALTH
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Submitted on: 26 April 2012.
Revised on: 12 July 2012.
Accepted on: 02 August 2012.
___________________JOURNAL OF OCCUPATIONAL HEALTH
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Submitted on: 26 June 2000.
Revised on: 22 September 2000.
Accepted on: 19 October 2000.
___________________JOURNAL OF OCCUPATIONAL HEALTH
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