An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
The oval-shaped oral cavity located at the apex of the digestive tract and consisting of two parts: the vestibule and the oral cavity proper. --consider also terms at ORAL ORO- STOMAT-
Conceptual system developed by Freud and his followers in which unconscious motivations are considered to shape normal and abnormal personality development and behavior.
Compounds, usually hormonal, taken orally in order to block ovulation and prevent the occurrence of pregnancy. The hormones are generally estrogen or progesterone or both.
Therapy whose basic objective is to restore the volume and composition of the body fluids to normal with respect to WATER-ELECTROLYTE BALANCE. Fluids may be administered intravenously, orally, by intermittent gavage, or by HYPODERMOCLYSIS.
