What's the difference between apex and crest?

Apex


Definition:

  • (n.) The tip, top, point, or angular summit of anything; as, the apex of a mountain, spire, or cone; the apex, or tip, of a leaf.
  • (n.) The end or edge of a vein nearest the surface.

Example Sentences:

  • (1) After 1 year, anesthesia was induced with chloralose and an electrode catheter placed at the right ventricular apex.
  • (2) Following injections of HRP into the apex of the heart, the sinoatrial (SA) nodal region and the ventral wall of the right ventricle, we observed that HRP-labeled sympathetic neurons were localized predominantly in the right stellate ganglia, and to a lesser extent, in the right superior and middle cervical ganglia, and left stellate ganglia.
  • (3) It is therefore suggested that salt water adaptation triggers a cellular reorganization of the epithelium in such a way that leaky junctions (a low resistance pathway) appear at the apex of the chloride cells.
  • (4) When HRP was injected in the left ventricular wall or the apex, few labeled neurons were identified in the DMN.
  • (5) The length of the diaphragmatic wall of the heart in both the right and left ventricle was equal to the sum of the length of the inflow tract and the thickness of the ventricular wall at the apex.
  • (6) However, the external muscle fibers of the ventricles ran clockwise from base to apex toward the center of the vortex, which had a striking resemblance to the normal rather than the mirror image pattern.
  • (7) In the RAO view with the collimator flat against the chest there was better resolution of the cardiac apex.
  • (8) Their proliferating regions are located in the apex tip, where the various cells originate.
  • (9) In these tissues, the viral DNA replicated at the site of inoculation and was transported first to the roots, then to the shoot apex and to the neighboring leaves and the flowers.
  • (10) The vertical distances were compared with measurements taken from periapical radiographs between the apex of each mesial root and the superior border of the mandibular canal prior to sectioning.
  • (11) Three of six patients in whom treatment failed had disease at the vaginal apex.
  • (12) We recommend this skin incision for young patients with pneumothorax if the chest CT scan confirms that the bullae or blebs are localized to the apex of superior segment of the lower lobe.
  • (13) MRI only offered advantages over CT in lesions of the orbital apex, the upper part of the orbit, and in the diagnosis of inflammatory processes.
  • (14) In the accelerated protocol, one, two, and then three extrastimuli were introduced at each of three basic drive train cycle lengths (350, 400, and 600 msec) at the right ventricular apex; the procedure was repeated at a second right ventricular site.
  • (15) Magnetic resonance imaging of the chest in patients with lung cancer is being investigated, but current studies comparing it with CT demonstrate no definite advantage at this time, with the possible exception of the lung apex in which T1 weighted thin-section coronal views are useful.
  • (16) The apex to base lung distribution of 99Tcm-C and 81Krm appeared to be similar.
  • (17) If a web has a low apex angle and the skin is elastic, the length-width ratio may be as great as 1.5:1.
  • (18) Double product increase was inferior to that recorded before atenolol administration; the difference became significant after 2 months and reached its apex after 6 months of treatment.
  • (19) HRCT scans at the apex of the thorax in all nine patients scanned at this level showed that extrapleural fat with interspersed vessels accounted for most of the plain radiographic opacity.
  • (20) To determine if anodal excitation during bipolar stimulation facilitates the initiation of sustained monomorphic ventricular tachycardia, nonsustained polymorphic ventricular tachycardia, or repetitive ventricular responses, both bipolar and cathodal unipolar programmed ventricular stimulation with one to three extrastimuli delivered during ventricular pacing at two rates from the right ventricular apex were performed in 28 patients evaluated for spontaneous sustained ventricular tachycardia or ventricular fibrillation (11 patients), nonsustained tachycardia (eight patients), or syncope (nine patients).

Crest


Definition:

  • (n.) A tuft, or other excrescence or natural ornament, growing on an animal's head; the comb of a cock; the swelling on the head of a serpent; the lengthened feathers of the crown or nape of bird, etc.
  • (n.) The plume of feathers, or other decoration, worn on a helmet; the distinctive ornament of a helmet, indicating the rank of the wearer; hence, also, the helmet.
  • (n.) A bearing worn, not upon the shield, but usually above it, or separately as an ornament for plate, liveries, and the like. It is a relic of the ancient cognizance. See Cognizance, 4.
  • (n.) The upper curve of a horse's neck.
  • (n.) The ridge or top of a wave.
  • (n.) The summit of a hill or mountain ridge.
  • (n.) The helm or head, as typical of a high spirit; pride; courage.
  • (n.) The ornamental finishing which surmounts the ridge of a roof, canopy, etc.
  • (n.) The top line of a slope or embankment.
  • (v. t.) To furnish with, or surmount as, a crest; to serve as a crest for.
  • (v. t.) To mark with lines or streaks, like, or regarded as like, waving plumes.
  • (v. i.) To form a crest.

Example Sentences:

  • (1) Hence, the absence of NGF receptors on premigratory neural crest and early migratory neural crest cultures was not due to enzymatic alterations of the receptor.
  • (2) Predominantly observed defects included neural crest cells in ectopic locations, both within and external to the neural tube, and mildly deformed neural tubes containing some dissociating cells.
  • (3) Our results suggest that cAMP may be an important regulator of phenotypic expression in at least some neural crest cell lineages.
  • (4) Neural crest cells give rise to various essential tissues in vertebrates.
  • (5) In the present study, we have compared the phosphorylation state of the fibronectin receptor in motile neural crest and somitic cells, in stationary somitic cells, and in Rous-sarcoma virus transformed-chick embryo fibroblasts, using immunoprecipitation following metabolic labeling.
  • (6) The staining method consisted of sequential treatment of slides with crest serum, fluorosceinated goat-antihuman and swine-antigoat antibodies, and propidium iodide.
  • (7) The participation of neural crest cells in development of the dermal skeleton is discussed by way of the repartition of the odontods within the pectoral fin.
  • (8) The talus was revascularized with a vascularized corticocancellous iliac crest bone graft.
  • (9) When the method proposed by Trela (1975) is applied, thin layers of the petrous crest are chiselled out until the common crus of the superior and posterior semi-circular becomes apparent.
  • (10) The center of resistance was located at 0.24 times the root length measured apical to the level of alveolar crest.
  • (11) By means of immunoreactivity for spot 35 protein, a novel cerebellar Purkinje cell-specific protein, the regional heterogeneity among non-pigmented ciliary epithelial cells of rats was demonstrated with reference to the antero-posterior and crest-valley directions of individual ciliary epithelial folds in immature and mature eyes.
  • (12) This is done by scoring the septal cartilage in its basal attachment to the maxillary crest, providing a "swinging door" which can be sutured finally as desired.
  • (13) The type II, III, IV, and V boutons appear mature at all ages examined but crest synapses formed by the type III terminals are observed in the later stages of the study.
  • (14) The use of the pectoralis major muscle only flap in conjunction with a free iliac crest bone graft for reconstruction of the mandible is described.
  • (15) The outer coat turned to be extremely sculptured, presenting as interlaced crests of various height.
  • (16) The effects of AAGTP are different in nervous tissue from other tissues, and experiments with that nucleotide have led to the discovery of a new, 32 kDa GTP-binding protein which appears only in neural crest cells.
  • (17) The neural crest has been suggested as the origin of the ectomesenchymomas.
  • (18) He had huge eyes, a wide, deep brow, an angel's mouth, with the upper lip crested.
  • (19) We have examined the distribution and function of the defined cell adhesion molecules, N-cadherin and N-CAM, in the emigration of cranial neural crest cells from the neural tube in vivo.
  • (20) On E7, a slender neuropil was present in the migrating cell clusters, but all the crest derived cells were uniform.