| LEH | Linear enamel hypoplasias |
|---|---|
| CEJ | cement enamel junction |
| DEJ | dentin enamel junction |
| EDJ | enamel dentine junction |
| rod cell | <ophthalmology, physiology> Major photoreceptor cell of vertebrate retina (about 125 million in a human eye). Columnar cells (about 40m long, 1m diameter) having three distinct regions: a region adjacent to and synapsed with, the neural layer of the retina contains the nucleus and other cytoplasmic organelles, below this is the inner segment, rich in mitochondria, that is connected through a thin neck (in which is located a ciliary body) to the outer segment. The outer segment largely consists of a stack of discs membrane infoldings that are incompletely separated in cones) that are continually replenished near the inner segment and that are shed from the distal end and phagocytosed by the pigmented epithelium. The membranes of the discs are rich in rhodopsin, the pigment that absorbs light. (03 Jul 1999) |
|---|---|
| rod cell of retina | 1. A straight and slender stick; a wand; hence, any slender bar, as of wood or metal (applied to various purposes). Specifically: An instrument of punishment or correction; figuratively, chastisement. "He that spareth his rod hateth his son." (Prov. Xiii. 24) A kind of sceptor, or badge of office; hence, figuratively, power; authority; tyranny; oppression. "The rod, and bird of peace." . A support for a fishing line; a fish pole. <machinery> A member used in tension, as for sustaining a suspended weight, or in tension and compression, as for transmitting reciprocating motion, etc.; a connecting bar. An instrument for measuring. 2. A measure of length containing sixteen and a half feet; called also perch, and pole. Black rod. <anatomy> Rods and cones, the elongated cells or elements of the sensory layer of the retina, some of which are cylindrical, others somewhat conical. Origin: The same word as rood. See Rood. Source: Websters Dictionary (01 Mar 1998) |
| rod disks | Membranous disk's of flattened sacs about 14 nm thick that occur in the outer segment of rods of the retina. (05 Mar 2000) |
| rod fibre | A part of the rod cell of the retina that extends to either side of the cell body; the inner rod fibre terminates in the spherule, a synaptic ending located in the outer plexiform layer. (05 Mar 2000) |
| rod granule | The nucleus of a retinal cell connecting with one of the rods. (05 Mar 2000) |
| rod monochromatism | Achromatopsia with absent colour vision, nystagmus, reduced visual acuity, and light aversion. Synonym: rod monochromatism, typical achromatopsia. (05 Mar 2000) |
| rod myopathy | A congenital myofibrillar abnormality in which small threadlike or rod-shaped bodies are scattered through the muscle fibres. It is marked by hypotonia and proximal muscle weakness. It is also called rod myopathy with reference to the threadlike (greek nema, thread) rods or myofibrils (latin fibrilla, a little fibre or threadlike structure). (12 Dec 1998) |
| rod nuclear cell | <pathology> Immature neutrophils released from the bone marrow reserve in response to acute demand. (18 Nov 1997) |
| rod outer segment | <ophthalmology, physiology> Major photoreceptor cell of vertebrate retina (about 125 million in a human eye). Columnar cells (about 40m long, 1m diameter) having three distinct regions: a region adjacent to and synapsed with, the neural layer of the retina contains the nucleus and other cytoplasmic organelles, below this is the inner segment, rich in mitochondria, that is connected through a thin neck (in which is located a ciliary body) to the outer segment. The outer segment largely consists of a stack of discs membrane infoldings that are incompletely separated in cones) that are continually replenished near the inner segment and that are shed from the distal end and phagocytosed by the pigmented epithelium. The membranes of the discs are rich in rhodopsin, the pigment that absorbs light. (03 Jul 1999) |
| rod outer segments | The portion of the retinal rod cell between the inner segment and the pigment epithelium layer of the retina. (12 Dec 1998) |
| rod vision | Vision when the eye is dark-adapted. See: dark adaptation, dark-adapted eye. Synonym: night vision, rod vision, scotopia, twilight vision. (05 Mar 2000) |
| withe-rod | <botany> A North American shrub (Viburnum nudum) whose tough osierlike shoots are sometimes used for binding sheaves. Source: Websters Dictionary (01 Mar 1998) |
| harrington rod insertion | <orthopaedics> A procedure that involves fusing together two or more vertebrae in the spine using either bone grafts or metal rods (Harrington rods). This procedure may be used to correct kyphosis or scoliosis. It is also used in those who require spine stabilisation due to vertebral damage from ruptures discs, fractures, osteomyelitis, osteoarthritis or tumour. (27 Sep 1997) |
| reduced enamel epithelium | The several layers of the enamel organ remaining on the enamel surface after formation of enamel is completed. Synonym: reduced enamel epithelium. (05 Mar 2000) |
| mottled enamel | Alterations in enamel structure due to excessive fluoride ingestion during tooth formation; varies in appearance from small white opacities to yellow and black spotting. Nanoid enamel, a condition of abnormal thinness of the enamel. Synonym: dwarfed enamel. Whorled enamel, enamel in which the rods assume a spiral or twisting course. (05 Mar 2000) |