Reference points located by visual inspection, palpation, or computer assistance, that are useful in localizing structures on or within the human body.
A dead body, usually a human body.
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
Instinctual patterns of activity related to a specific area including ability of certain animals to return to a given place when displaced from it, often over great distances using navigational clues such as those used in migration (ANIMAL MIGRATION).
Three-dimensional representation to show anatomic structures. Models may be used in place of intact animals or organisms for teaching, practice, and study.
The measurement of the dimensions of the HEAD.
The anatomical frontal portion of the mandible, also known as the mentum, that contains the line of fusion of the two separate halves of the mandible (symphysis menti). This line of fusion divides inferiorly to enclose a triangular area called the mental protuberance. On each side, inferior to the second premolar tooth, is the mental foramen for the passage of blood vessels and a nerve.
The function of the eye that is used in the intermediate level of illumination (mesopic intensities) where both the RETINAL ROD PHOTORECEPTORS and the RETINAL CONE PHOTORECEPTORS are active in processing light input simultaneously.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
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.
Specialized PHOTOTRANSDUCTION neurons in the vertebrates, such as the RETINAL ROD CELLS and the RETINAL CONE CELLS. Non-visual photoreceptor neurons have been reported in the deep brain, the PINEAL GLAND and organs of the circadian system.
The process in which light signals are transformed by the PHOTORECEPTOR CELLS into electrical signals which can then be transmitted to the brain.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
Photosensitive afferent neurons located primarily within the FOVEA CENTRALIS of the MACULA LUTEA. There are three major types of cone cells (red, blue, and green) whose photopigments have different spectral sensitivity curves. Retinal cone cells operate in daylight vision (at photopic intensities) providing color recognition and central visual acuity.