Funding for this research was provided by:
the Chinese National Natural Science Foundation (81671616, 81471603)
Jiangsu Provincial Commission of Health and Family Planning Foundation (H201317, H201623)
Science Foundation of Nantong City (MS32015021, MS2201564, MS22016028, MS22016019)
Science and Technology Foundation of Nantong City (HS2014071, HS2016003)
Received: 23 September 2017
Accepted: 2 May 2018
First Online: 16 May 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the Afliated Hospital of Nantong University (approval number 2017-K003), and all selected patients and control individuals signed an informed consent form before enrolment, which was carried out in accordance with the Helsinki Declaration.
: The authors declared that they have no competing interests.
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