transition zone

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an encircling region or area; by extension, any area with specific characteristics or boundary.
ciliary zone the outer of the two regions into which the anterior surface of the iris is divided by the collarette.
comfort zone an environmental temperature between 13 and 21°C (55 and 70°F) with a humidity of 30 to 55 per cent.
epileptogenic zone an area, stimulation of which may provoke an epileptic seizure.
erogenous zone (erotogenic zone) in psychoanalytic theory, an area of the body through which the libido expresses itself and which is therefore susceptible to erotic excitation upon stimulation; the primary sites are the oral, anal, and genital regions, but the other body orifices, breasts, and skin are also included.
zone of partial preservation in spinal cord injury, an area of only partial damage that may include up to three consecutive spinal segments caudal to the level of the injury.
pupillary zone the inner of the two regions into which the anterior surface of the iris is divided by the collarette.
transition zone (transitional zone) any anatomical region that marks the point at which the constituents of a structure change from one type to another; for example, the circle in the equator of the ocular lens in which epithelial fibers are developed into lens fibers, or the zone (anocutaneous line) that marks the junction of stratified squamous epithelium with columnar epithelium.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

transition zone

1. Tissue that includes two or more cell types linking two distinct regions of an organ.
Squamocolumnar junction.
See also: zone
Medical Dictionary, © 2009 Farlex and Partners
References in periodicals archive ?
In conclusion, the high residual thermal energy in MWA and RFA induced secondary damage beyond the direct coagulation zone, and this energy could be dissipated by subsequent cooling-circulation, contributing to both smaller ablation zone and transition zone. However, the phenomenon was illustrated only in animal experiments in the present study, so further clinical trials are warranted to determine the role of residual thermal energy in MWA and RFA in the treatment of solid tumors.
Equation (15) is the generalized pressure derivative equation for transition zone of oil-water or gas-water systems.
Regarding prostate gland volume reduction, statistical significance was achieved in the total prostate and the transition zone. It is believed that nonspherical PVA particles have more chance to perform proximal embolization than microspheres, which may reduce the possibility of clinical success [27].
Another study done by Proctor ML et al [9] has noted that in rectosigmoid Hirschsprung disease, the location of the radiographic transition zone correlates accurately with the level of aganglionosis in nearly 90%.
Additional benefit of functional imaging over T2 weighted images in assessing the transition zone tumour is limited, as areas of benign stromal hyperplasia may show enhancement on DCE and restricted diffusion on DWI.
The STGM shows a nearly complete ophiolitic sequence (Penrose Conference, 1972) ranging from foliated peridotite at the base through MantleCrust Transition Zone in middle, to the crustal rocks at top (Fig.
That is, the plastic deformation in the transition zone accompanied with certain amount of heat takes place during the tensile test at temperature below 40[degrees]C in air, but no force oscillation appears.
The biogenic carbonate sand from Porto Santo Island consists mainly of bioclasts of calcareous red algae (Rhodophyta), sand-bathing traditionally taking place outdoors in the dry and warm sand of the transition zone beach/frontal dune, along the southern coast of the island.
A management plan was created for the land, which sits in the transition zone between aspen parkland and the boreal forest, in the mid-1990s, indicating that there is a "high habitat capability for wildlife" including black bear, beaver, coyote, mink, otter, muskrat and wolf and northern flying squirrel.
The mean global transparency was 1.16 m (n = 930; SD = 0.65), the peaks were 5.76 m in the fluvial zone, 4.86 m in the transition zone and 2.83 m in the lacustrine zone (Figure 2).
The area boxed by the dashed line in Figure 2 illustrates the transition zone, in which the patient's performance fluctuates between unable to perform (rating = 0), partial performance (rating = 1), and near normal performance (rating = 2).
Everything in between is the transition zone. What we think of as "Northern Ontario" is just the transition zone, and most of us are not in it.

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