(n.) A carpentry obstruction, stockade, or other obstacle made in a passage in order to stop an enemy.
(n.) A fortress or fortified town, on the frontier of a country, commanding an avenue of approach.
(n.) A fence or railing to mark the limits of a place, or to keep back a crowd.
(n.) An any obstruction; anything which hinders approach or attack.
(n.) Any limit or boundary; a line of separation.
Example Sentences:
(1) Here we have asked whether protection from blood-borne antigens afforded by the blood-brain barrier is related to the lack of MHC expression.
(2) We conclude that chloramphenicol resistance encoded by Tn1696 is due to a permeability barrier and hypothesize that the gene from P. aeruginosa may share a common ancestral origin with these genes from other gram-negative organisms.
(3) The findings clearly reveal that only the Sertoli-Sertoli junctional site forms a restrictive barrier.
(4) This suggests that a physiological mechanism exists which can increase the barrier pressure to gastrooesophageal reflux during periods of active secretion of the stomach, as occurs in digestion.
(5) Comparison of the 50% binding concentrations of the compounds for the various PBPs of the five strains with their antibacterial activity indicates that the different antibiotics are excluded to a greater or lesser degree by the outer membrane permeability barrier and that the exclusion is most pronounced in P. aeruginosa.
(6) Preservation of dopaminergic and H1 neurotransmission, probably within the blood barrier, is needed to allow the neuroendocrine transduction of cholinergic inputs, whereas the role of 5-HT neurotransmission remains uncertain.
(7) Their levels in urine are a useful indicator of the integrity of membrane barriers of the kidney glomerular capillary wall.
(8) The IgG index (formula: see text) corrects for the influence of serum protein abnormalities as well as a bloodbrain barrier damage and is, therefore, a better measure for the presence of an IgG elevation in CSF due to IgG synthesis, when compared with other IgG quotients commonly used.
(9) In the far east is the arid, depressed country leading down Hell’s Canyon, which bottoms out at the Snake River, which the wolves crossed when they moved from Idaho, and which they now treat more as a crosswalk than a barrier.
(10) No signs of the blood-brain barrier disruption were observed.
(11) Although no anatomical 'barrier' has been described, it has been suggested that the gel mucus and epithelial phospholipids are constituents.
(12) Despite their wide dispersion, Vmax and the stereological determinations correlated strongly at 2 mo of age, confirming that Vmax is a robust indicator of the surface area of the air-blood barrier.
(13) Developmental changes are delineated, with particular reference to recent work on the ovine blood-brain barrier.
(14) Features of barrier island physiography and ecology were studied relative to selective bait deployment and site biosecurity.
(15) This study sought to determine if and why barriers to the over-the-counter purchase of syringes in the St. Louis metropolitan area might exist, given that no ordinance prohibits such a sale there.
(16) It is suggested that the intercalated disc functioned as a barrier to the freezing process.
(17) To explain some of these results a theoretical model is presented to demonstrate that while short circuiting can block the passive ionic movement, it will cause an increase in the energy consumption of the system and introduce certain important changes in the ionic barriers and e.m.fs.
(18) Our results show that paramagnetic enhancement with T1-weighted imaging adds specificity and enables rapid assessment of abnormalities of the blood-brain barrier.
(19) A functional impairment of the amino acid transport systems at the level of the blood-brain barrier seems to play a crucial role in causing deleterious modifications of the synaptic neurotransmission in the central nervous system.
(20) There was a significant correlation between the lesion index and the PD reduction, although the integrity of the resting gastric mucosal barrier remained unaltered.
Boundary
Definition:
(n.) That which indicates or fixes a limit or extent, or marks a bound, as of a territory; a bounding or separating line; a real or imaginary limit.
Example Sentences:
(1) Patients with papillary carcinoma with a good cell-mediated immune response occurred with much lower infiltration of the tumor boundary with lymphocyte whereas the follicular carcinoma less cell-mediated immunity was associated with dense lymphocytic infiltration, suggesting the biological relevance of lymphocytic infiltration may be different for the two histologic variants.
(2) In contrast, boundary layer diffusion is operative in the release from the matrixes prepared by compression of physical mixtures.
(3) The review will now be delayed for five years, leaving the next election to be fought on the existing constituency boundaries, and seriously damaging David Cameron's chances of winning an overall majority in 2015.
(4) In Europe such escapees often find themselves recaptured by boundary adjustments.
(5) This gene was previously shown to have a DNase I- and S1-sensitive site for which the boundaries varied with the cell cycle, and we have now precisely mapped these modifications.
(6) Past measurements have shown that the intensity range is reduced at the extremes of the F0 range, that there is a gradual upward tilt of the high- and low-intensity boundaries with increasing F0, and that a ripple exists at the boundaries.
(7) The problem, however, is that this scale of economic planning and management is entirely outside the boundaries of our reigning ideology.
(8) His first ball reaches Ali at hip height and he flicks him to fine leg for a boundary that takes him to a quite epic century.
(9) Upon estimation of 5' and 3' boundaries, a 497 base stretch of homology with the TOP1 mRNA was found.
(10) Responses above the associated boundary decreased stimulus intensity, responses below the associated boundary increased stimulus intensity.
(11) The position of the sedimenting boundary can be observed at any time during the run, and up to six 'photographs' can be recorded for subsequent analysis.
(12) If figurative language is defined as involving intentional violation of conceptual boundaries in order to highlight some correspondence, one must be sure that children credited with that competence have (1) the metacognitive and metalinguistic abilities to understand at least some of the implications of such language (Lakoff & Johnson, 1980; Nelson, 1974; Nelson & Nelson, 1978), (2) a conceptual organization that entails the purportedly violated conceptual boundaries (Lange, 1978), and (3) some notion of metaphoric tension as well as ground.
(13) First, chains are constrained by their inability to penetrate the boundary.
(14) Within the developing CNS of mouse embryos the anterior boundaries of expression are specific for each gene.
(15) Cities and counties across the US have also passed laws that prohibit such performances from occurring within their boundaries.
(16) The rate of forward patch movement was generally greater at positions further behind the boundary.
(17) He said the proposals had been directed at seats that have not changed hands for many years, but said with the redrawing of the constituency boundaries required by David Cameron's desire to cut the number of constituencies no safe seats as previously defined would exist.
(18) A line iterative technique is described to solve numerically the resulting coupled system of nonlinear partial differential equations with physiologically relevant boundary and entrance conditions.
(19) Many Iranian women are already pushing the boundaries , and observers in Tehran say women who drive with their headscarves resting on their shoulders are becoming a familiar sight.
(20) And then, as the Guardian revealed at the weekend, there is the potentially devastating effect of the boundary changes, which can’t really be brought in before an early election but will radically tilt the field by 2020.