title: A forgotten cause of false negative rapid urease test: formalin contamination of the sample.
authors.forename: Ersan
authors.initials: E
authors.lastname: Ozaslan
authors.forename: Tankut
authors.initials: T
authors.lastname: Koseoglu
authors.forename: Tugrul
authors.initials: T
authors.lastname: Purnak
authors.forename: Ayla
authors.initials: A
authors.lastname: Yildiz
mesh_terms: D005188:False Negative Reactions; D005557:Formaldehyde / Q000494:pharmacology*; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000201:enzymology*; D006801:Humans; D013048:Specimen Handling; D014510:Urease / Q000378:metabolism*
chemical_list: D005557:Formaldehyde; D014510:Urease