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\bibitem{Clemen_etal2020} {\textquotedblleft}\textit{Physical Plasma-Treated Skin Cancer Cells Amplify Tumor Cytotoxicity of Human Natural Killer (NK) Cells}{\textquotedblright}. Clemen R, Heirman P, Lin A, Bogaerts A, Bekeschus S, Cancers \textbf{12}, 3575 (2020).   http://doi.org/10.3390/cancers12123575

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