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2. Abbott (2020) Cartridge and test information. Available at: https://www.pointofcare.abbott/int/en/offerings/support/i-stat/cartridge-test-information-sheets.
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4. Two-center clinical evaluation of a new automated fluorometric immunoassay for the quantitative analysis of total betaeta-human chorionic gonadotropin;Azzazy;Clin. Biochem.,2003
5. Pregnancy of unknown location: a consensus statement of nomenclature, definitions, and outcome;Barnhart;Fertil. Steril.,2011