(n.) The posterior of the three principal divisions of the brain, including the epencephalon and metencephalon. Sometimes restricted to the epencephalon only.
Example Sentences:
(1) These observations and a relatively high incidence of hindbrain tumours are suggestive of an embryonic origin for most of the cases.
(2) Among the 18 hindbrain areas, LCGU was decreased by pentobarbital by 15-55% (range 50-157 and 28-110 mumol.100 g-1.min-1 in control and treated rats, respectively).
(3) Under conditions of chronic or repeated seizure activity over prolonged time periods, seizures evoked from the hindbrain can recruit forebrain circuits; conversely, repeated stimulation of forebrain limbic circuits (e.g., kindling) can modify susceptibility to brainstem convulsions.
(4) These differences in effects on specific neurotransmitter systems reflect the fact that the forebrain is most severely affected by early ethanol administration, whereas the hindbrain is relatively spared.
(5) Microscopic immunohistochemical localization of CRABP found the highest concentration in the ventral midbrain and in the ventral and lateral sides of the hindbrain and spinal cord; CRABP was also abundant in tongue, limb, and skin.
(6) The question raised was whether cells from the graft would be able to yield the neural crest derivatives normally arising from the hindbrain and vagal crest, such as carotid body type I and II cells, enteric ganglia, Schwann cells located along the local nerves, and the nonneuronal contingent of cells in the host nodose ganglion.
(7) Potency profiles of these and other analogues suggest that the renal medulla and dorsal hindbrain vasopressin receptors represent different subtypes.
(8) During this period, the intensity of transcription in presomitic and somitic mesoderm declines relative to that in the overlying neural ectoderm, and the transcription boundary within the presumptive hindbrain region sharpens.
(9) In detailed examination of alpha Enhb-1 and 4D9 localization, we find previously undetected patterns of En protein localization in the prechordal plate, hindbrain, myotome, ventral body-wall mesoderm, and extraembryonic membranes.
(10) The results were as follows: (1) III-V interpeak latency (IPL) decreased progressively from prolonged to the normal range with growth until 25 years of age; (2) I-III IPL tended to prolong gradually from the normal range; (3) these findings may indicate that the natural history of Chiari II malformation is delayed maturation of the brain stem and intensification in the elongation and stretching of the hindbrain and lower cranial nerves.
(11) Both genes are expressed in the developing midbrain and its junction with the hindbrain.
(12) Both mutants also have altered polyamine synthesis and accumulation, particularly in the hindbrain and spinal column.
(13) With due consideration for the clinical findings and those recorded by Doppler ultrasound and computed tomography, vertebral angiography is indicated in vertebrobasilar occlusive disease if anticoagulation, percutaneous transluminal angioplasty (PTA) or local intraarterial fibrinolytic therapy (LIF) of the hindbrain circulation is intended, and also if there is a discrepancy between the clinical findings and the results of computed tomography or Doppler ultrasound examination.
(14) The results indicate that the mesencephalon is the principal site for the precursor cells of the ciliary ganglia and clearly rules out any contribution to the ganglia from either the forebrain or hindbrain levels.
(15) In specimens of shovelnose, Scaphirhynchus platorynchus, and Atlantic sturgeon, Acipenser oxyrhynchus, and paddlefish, Polyodon spathula, evoked potentials recorded from the hindbrain and elicited by electric fields reached maximum amplitude within the DON and decreased in amplitude through the cerebellar crest.
(16) We show that neurons whose axons reach the hindbrain first survive for a short time in culture before responding to brain-derived neurotrophic factor (BDNF).
(17) Retinoic acid (RA) and its congeners accumulate in a saturable manner in neural crest and neural crest-derived cells, in the hindbrain, and the spinal cord of mouse embryos.
(18) In general the telencephalon made greatest use of ketone bodies, whereas the hindbrain used least.
(19) However, there was a significant linear relationship between carbon dioxide tension and the percent of the microvasculature perfused in the hindbrain.
(20) Na+, K+-ATPase activity was significantly reduced in the forebrain region at the stage of mild encephalopathy (43 h after injection), while at the deeper stage of coma (43-53 h after injection) enzyme activity was further reduced in the forebrain region and was also significantly reduced in the hindbrain region.
Medulla
Definition:
(n.) Marrow; pith; hence, essence.
(n.) The marrow of bones; the deep or inner portion of an organ or part; as, the medulla, or medullary substance, of the kidney; specifically, the medula oblongata.
(n.) A soft tissue, occupying the center of the stem or branch of a plant; pith.
Example Sentences:
(1) Furthermore, the local interneurons make extensive efferent synaptic connections with unidentified neurons in the terminal medulla.
(2) These findings suggest that AAT participates in the synthesis of transmitter aspartate in the medulla oblongata of the rat.
(3) These included the noradrenergic, TH- and DBH-immunoreactive cell groups of the pons and medulla.
(4) Size of both areas gradually decreased as the medulla filled with plasma cells, 7-30 days after injection.
(5) Obvious restitution of the thymic medulla was evident about 14 days after withdrawal of FK506.
(6) + inf., pons + medulla), rCBF increased toward the control level gradually, and it completely recovered 60 min after recirculation.
(7) It is well established that the renal medulla exerts a potent endocrine-like antihypertensive action.
(8) It was found that within the dorsal part of the well known pressor area there is a narrow strip, 2.5 mm lateral from the mid line, starting ventral to the inferior colliculus and ending in the medulla close to the floor of the IV ventricle, from which vasodilatation in skeletal muscles is selectively obtained.
(9) Urea decreased and valine increased in the TD medulla-pons.
(10) The sizes of adrenaline (A) and noradrenaline (N) cells in the adrenal medulla of nonoperated (NO), sham-operated (SPX), and pinealectomized (PX) male rats (n = 126) were investigated by quantitative light microscopy.
(11) Injection of horseradish peroxidase into the rostral ventrolateral medulla (RVLM) led to heavy retrograde and anterograde labeling in the region of the hypothalamus that yielded the CRDR when stimulated electrically.
(12) The object of these studies was to investigate whether destruction of the renal medulla in normal rats would alter vascular capacitance.
(13) The presence in lamprey kidney of a loop which is similar to Henle's loop in mammals and birds indicates that the development of the system of osmotic concentration conditioned by the formation in the kidney of the medulla and from a sharp increase in renal arterial blood supply.
(14) Our results suggest that multiple receptors and signal transduction pathways are involved in the regulation of the tyrosine hydroxylase gene in the rat adrenal medulla.
(15) In hypertensive rats (SHR) the density of alpha 2-adrenoceptors was reduced in the cerebral cortex, hypothalamus and medulla oblongata (20-27%), as was the dose-pupillary response curve for clonidine (1.8-fold).
(16) An antihypertensive function in systemic blood pressure control has been attributed to the renal medulla.
(17) 1 After the injection of labelled procaine and lidocaine in mice, the location and concentration of radioactivity was demonstrated by autoradiographical methods.2 An accumulation in some endocrine cells such as the pancreatic islets, the hypophysis, the adrenal medulla and certain cells of the thyroid (probably representing the calcitonin-producing parafollicular cells) was shown.3 After the injection of [(14)C]-procaine in chicks, an accumulation of radioactivity was observed in the ultimobranchial gland (which produces calcitonin in birds), but not in the thyroid.4 Radioactivity was also shown to be strongly concentrated in structures containing melanin, such as the pigment of the eye, skin and hair and in some organs involved in the metabolism and excretion of these drugs.
(18) Histologically, increased amounts of fibrotic tissue in the medulla and the cortex were found together with tubular atrophy.
(19) Two well-defined zones are observed both in the medulla and in the cortex.
(20) One infant had a unilateral infarction in the medulla and another showed extensive gliosis in the brainstem tegmentum along with a large infarction in the region of the anterior cerebral artery.