Funding for this research was provided by:
The Perklén foundation
Received: 28 March 2018
Accepted: 7 May 2018
First Online: 11 June 2018
Ethics approval and consent to participate
: All patients and controls gave a written informed consent. The study was approved by the Ethical Committee of the hospital district of Southwest Finland, and it was conducted in accordance with the Declaration of Helsinki as revised in 1996.
: The authors declare that they have no competing interests.
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