Received: 13 August 2018
Accepted: 3 January 2019
First Online: 18 January 2019
Ethics approval and consent to participate
: All procedures performed in this study involving human participants were in accordance with the ethical standards of the Ethical Committee of the Alexandria Faculty of Medicine with approval reference number of (0303820) dated 18/1/2018. Informed consent to participate in the study was obtained from all participants.
: Not applicable.
: The author declares that he has no competing interests.
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