A bone marrow biopsy or aspirate usually shows hemophagocytosis. Lymph node aspirate and chylous fluid may also yield microfilariae. The peripheral blood and bone marrow aspirate findings in copper deficiency can mimic myelodysplastic syndrome. Sometimes, a bone marrow examination will include both an aspirate and a biopsy. Pulmonary infection have to be ruled out by endotracheal aspirate or BAL. Patients typically aspirate food because they have esophageal, gastric or neurologic problems. A surgeon can aspirate the fluid with a needle. The reliable method is to aspirate some fluid from the tube with a syringe. For a silver nitrate test on gastric aspirate, diluted gastric content can be positive. People who aspirate while standing can have bilateral lower lung lobe infiltrates. Under aspirate mutation (), unvoiced stops become fricatives. It is normally possible to aspirate five litres of rumen liquor using this device. The nucleus emulsification makes it easier to aspirate the particles. Avestan has retained voiced sibilants, and has fricative rather than aspirate series. An "aspirate" can also be obtained from the sternum (breastbone).