What's the difference between chiasma and modiolus?
Chiasma
Definition:
(n.) A commissure; especially, the optic commissure, or crucial union of the optic nerves.
Example Sentences:
(1) For the case described by the author primary tearing of the chiasma due to sudden applanation of the skull in the frontal region with burstfractures in the anterior cranial fossa is assumed.
(2) There were, however, significant differences among investigators in reported mean chiasma frequencies.
(3) In only one case was the B chromosome significantly associated with an increase chiasma frequency.
(4) Chromosomal analysis of cells undergoing diakinesis showed significantly lower chiasma frequency in elderly men, compared with a group of younger control males and also with infertile males.
(5) Furthermore we found increased chiasma frequencies in diakinesis--metaphase I (MI) and reduced nondisjunction frequencies at anaphse I as a result of the treatments applied.
(6) A case of cystic optic glioma involving chiasma and bilateral posterior optic pathway was reported.
(7) CT revealed a calcified lesion which must be a vessel in the chiasma cistern just adjacent to the basilar artery which was relatively larger than normal.
(8) In the unanaesthetised animals the proportions of units responding were high (60%) and did not differ significantly between regions for each type of stimulation investigated: visual, auditory and optic chiasma shocks.
(9) Tangential, centrifugal and incerta sedis-fibres, which originate either from cell bodies in the cell body layer at the periphery of the outer chiasma or more centrally, terminate in the synaptic region of the lamina.
(10) This new function is derived by assuming that all chromosome arms except the short arms of acrocentric chromosomes hav an obligatory chiasma, and that the remaining chiasmata are distributed at random; assumptions which may correspond reasonably well to reality.
(11) Thus from just beyond the chiasma the fibres had already achieved the major uniaxial rearrangement necessary to establish a normal tract distribution despite the eye translocation.
(12) Pathologically there was necrosis of the optic chiasma and focal areas of myelin sheath vacuolation or demyelination in certain areas of the brain, especially in the cerebellar peduncles.
(13) Predictions from the chiasma map can be confirmed or refuted only by genetic evidence for which the estimates of this paper serve as initial values to begin maximum likelihood iteration.
(14) Male meiosis in Mesostoma ehrenbergii ehrenbergii (2x = 10) is characterized by extreme restriction of chiasma formation; 3 pairs of chromosomes form bivalents at metaphase I which are associated by single very distally localized chiasma, while two pairs of chromosomes remain as unpaired univalents.
(15) It was found that both of the heat-induced decreases in chiasma frequency which can be obtained (Effects 2 and 3), were dominant over both of the different types of increase (Effects 1 and 4), with the largest decrease (Effect 3) being dominant over all others.
(16) In precocious puberty we found 1 ectopic pinealoma and 2 gliomas of the chiasma.
(17) The latter refers to the Willis atypical polygons, which determine important atipies in the topographical distribution of the chiasma's arteries and optical bandelets.
(18) In the rostral third of the SCN there are relatively few optic synapses which are found close to the optic chiasma.
(19) In addition to this abnormality there is a misrouting of the optic nerve fibers, with some fibers from the temporal retina following a crossed route at the chiasma and terminating in the contralateral cortical hemisphere.
(20) The chiasma frequency estimates were based on 15 son-sire pairs, the translocation heterozygotes being maintained in a Swiss random-bred genetic background.
Modiolus
Definition:
(n.) The central column in the osseous cochlea of the ear.
Example Sentences:
(1) The electrodes can be implanted in bundles through the round window or into the modiolus; they can, however, also be introduced individually through several drill holes in the promontory for placement in the scala tympani and vestibuli.
(2) The peripheral and central axons also degenerated, and the losses of both the radial nerve fibers in the osseous spiral lamina and the central axons passing into the modiolus displayed selective topographies that paralleled the cell loss within the spiral ganglion.
(3) In the developing cochlear nerve, a central tissue projection is present before birth, but regresses somewhat before a marked outgrowth of central nervous tissue along the nerve takes place, which reaches into the modiolus during the first week postnatum.
(4) A trough around the modiolus was drilled, and the electrode array was placed in it.
(5) The function of the vessel loops in the modiolus is to flatten the pulse wave as well as to regulate the blood flow in the microvascular bed by vasomotion.
(6) The cochlea was dissected into three parts: organ of Corti + modiolus (OC + M), lateral wall (LW), and cochlear nerve (CN), and then PG's formed by these tissues were determined after a 5-min incubation of the homogenates.
(7) Implantation involved creation of a channel for the electrode to wrap around the modiolus.
(8) Each unit begins with special blood vessel convoluts in the modiolus, consisting of loops of arterioles.
(9) The openings in the bone on the scala vestibuli and tympani sides of the modiolus are considered to be communication routes for the transport of fluids from the perineural and perivascular spaces in the modiolus to the perilymph in the scalae.
(10) In cryostat sections, tyrosine hydroxylase and dopamine beta-hydroxylase-like immunoreactivities fibers were seen in the modiolus that did not extend to the organ of Corti.
(11) A vessel, formed by the confluence of the vascular network on the modiolar wall and having a spiral course into the internal auditory meatus was found in the modiolus of the basal turn.
(12) HRP permeated interendothelial spaces lining the modiolus to reach the scala vestibuli lymphatics close to all the above areas were also permeated by HRP, but the inner tunnel was devoid of the marker.
(13) Multiple anomalies include: abnormal narrowing of the crus commune-utricle junction, superiorly located crus commune and posterior semicircular canal, underdeveloped modiolus, absence of the bony septum between the middle and apical coil (existence of scala communis in left ear), abnormally small internal auditory meatus, and abnormal direction of internal auditory canal, large cartilaginous mass around the superior semicircular canal and in the tympanic end of the fissula ante fenestram, small facial nerve, large facial bony canal dehiscence, anomalic stapes, etc.
(14) These scanning electron microscopic findings were confirmable by serial sections of the dural veins in the internal auditory meatus and the modiolus.
(15) Preliminary studies have shown that the nerve will survive the placement of electrodes both into the modiolus and the scala tympani.
(16) Some accumulation of lidocaine was found in the modiolus, but almost none in the stria vascularis.
(17) These regenerating cochlear nerve fibers were found in the osseous spiral lamina, modiolus and internal auditory meatus, but these fibers atrophied and disappeared afterward.
(18) However, detailed information concerning the vasculature of the modiolus is still unavailable, and even the existence of venous drainage through the internal auditory meatus is not agreed upon.
(19) The modiolus on the scala vestibuli side had a canal for the spiral modiolar artery.
(20) The spiral ganglion dendrites within the osseous spiral lamina of the basal turn project radially, nearly perpendicular to the central axis of the modiolus.