The clinical pathology laboratory also enables the veterinarian to examine and analyze various body fluids and cells that may be present in a particular sample. Fluids may be aspirated by syringe from body cavities and cysts, and studied in the same manner as a urine sample. Microscopically examining the cellular portion or the sample is called cytologic analysis. Pressing a microscope slide against a particular tissue results in the deposition of some of its cells on the slide's surface. Such impression smears can be made from tissue masses (lumps, etc), abscesses, discharges, wounds, etc. Various stains can be used to prepare this impression smears before their microscopic examination. Cytologic and fluid analyses are valuable diagnostic tools in avian medicine.