Fine-needle aspiration. Fine-needle aspiration (FNA), or fine-needle aspiration cytology (FNAC), is a diagnostic procedure used to investigate lumps or masses. In this technique, a thin (23-25 gauge), hollow needle is inserted into the mass for sampling of cells that, after being stained, will be examined under a microscope.
Blood is a bodily fluid in humans and other animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells.he blood cells are mainly red blood cells (also called RBCs or erythrocytes), white blood cells (also called WBCs or leukocytes) and platelets. The most abundant cells in vertebrate blood are red blood cells.
The main function of blood vessels is to carry blood through the body. The blood carries oxygen, nutrients, and wastes that need to move around the body. There are three kinds of blood vessels: arteries, veins, and capillaries. The arteries carry blood away from the heart and transport it to the rest of the body.