All articles starting with N
16,460 articles
Neuroendocrine neoplasm of appendix
Neuroendocrine neoplasm of appendix (appendiceal NEN, ORPHA:100079): rare sporadic appendiceal tumor, second most common digestive endocrine tumor, comprising classic low-grade NET and the more aggressive goblet cell adenocarcinoma; usually incidental, treated by appendectomy or right hemicolectomy.
Neuroendocrine neoplasm of esophagus
A neuroendocrine neoplasm of the esophagus is a rare tumor with neuroendocrine features, including well-differentiated tumors, poorly differentiated carcinomas, and mixed neoplasms, with median survival of 22.5 months.
Neuroendocrine tumor
Neuroendocrine tumor (NET): a cancer of the neuroendocrine cell system, mostly gastrointestinal or pancreatic, graded by Ki-67 (G1 20%); rising US incidence, treated with surgery, somatostatin analogs, everolimus, sunitinib, and 177Lu-DOTATATE PRRT.
Neuroendocrine tumor of stomach
A neuroendocrine tumor of the stomach, also called a gastric NET or gastric carcinoid, is a rare tumor arising mostly from ECL cells of the gastric mucosa.
Neuroendocrine tumor of the colon
Neuroendocrine tumor of the colon (colonic NET, ORPHA:100080) is a rare enterochromaffin-cell tumor of the large intestine, mostly cecal or ascending; distinguished from colonic NEC and MiNEN by WHO 2022 grading and Ki-67 index.
Neuroendocrine tumor of the rectum
Neuroendocrine tumor of the rectum (rectal NET), a rare epithelial tumor of enterochromaffin cell origin, usually mid-rectum, slow-growing and often incidental; graded G1–G3 and treated by endoscopic or surgical resection based on size, grade, and nodal status.
Neuroendocrinology
Neuroendocrinology: the study of anatomical and functional relationships between the nervous and endocrine systems (MeSH D009452, 1986); journals Neuroendocrinology (Karger, 1965) and Journal of Neuroendocrinology (BSN, 1989).
Neuroendoscopes
Neuroendoscopes (neuroendoscopes, MeSH D044582) are rigid or flexible endoscopic instruments for visual examination and surgery within the nervous system, used in hydrocephalus, intraventricular tumors, hemorrhage, and skull base procedures.
Neuroendoscopy
Neuroendoscopy is a minimally invasive neurosurgical technique using an endoscope, introduced through a burr hole or the nose, to treat disease inside the brain ventricles and skull base.
Neuroevolution
Neuroevolution is a machine learning approach that uses evolutionary algorithms to optimize neural networks, maintaining a population of candidate networks rather than training weights by gradient descent.
Neuroevolution of augmenting topologies
Neuroevolution of augmenting topologies (NEAT) is an evolutionary algorithm introduced by Kenneth Stanley and Risto Miikkulainen in 2002 that evolves both neural network weights and structure, growing from minimal networks.
Neurofeedback
Neurofeedback (EEG biofeedback, neurotherapy): real-time feedback of brain activity to train self-regulation, founded on Kamiya's 1960s alpha work and Sterman's SMR epilepsy research; ADHD meta-analyses find no stand-alone benefit.
Neuroferritinopathy
Neuroferritinopathy (hereditary ferritinopathy, NBIA3) is a rare autosomal dominant adult-onset movement disorder from FTL ferritin light chain mutations, causing brain iron accumulation, chorea or dystonia, low serum ferritin, and basal ganglia cavitation on MRI.
Neurofibrillary tangle
Neurofibrillary tangles: intracellular aggregates of hyperphosphorylated tau in paired helical filaments, defining lesions of Alzheimer's disease, staged by the Braak system, tracked by tau PET and MTBR-tau243, and targeted by etalanetug.
Neurofibroma
Neurofibroma: benign peripheral nerve sheath tumor of Schwann cell origin, named by von Recklinghausen in 1882; occurs sporadically or in NF1, with dermal and plexiform subtypes, treated by surgery or selumetinib.
Neurofibromatosis
Neurofibromatosis (von Recklinghausen's disease) is a group of autosomal dominant tumor-predisposition disorders: NF1 (chromosome 17, neurofibromin), NF2-related schwannomatosis (chromosome 22, merlin), and schwannomatosis, causing nerve sheath tumors, skin lesions, and hearing loss.
Neurofibromatosis type 3
Neurofibromatosis type 3 (NF3), ICD-11 code LD2D.12, is a legacy designation for a third neurofibromatosis form; historically the mixed type (Riccardi 1982), later segmental (Carey 1986), now outside the NF1/NF2-related schwannomatosis/schwannomatosis framework.
Neurofibromatosis type I
Neurofibromatosis type I (NF1, von Recklinghausen disease): autosomal dominant tumor predisposition syndrome from NF1 gene loss on 17q11.2; café au lait macules, neurofibromas, MPNST risk; treated with MEK inhibitors selumetinib and mirdametinib.
Neurofibromatosis type II
Neurofibromatosis type II, or NF2-related schwannomatosis, is a genetic tumor predisposition syndrome causing bilateral vestibular schwannomas, meningiomas, and spinal ependymomas, caused by NF2 gene variants.
Neurofibromatosis-Noonan syndrome
Neurofibromatosis-Noonan syndrome (NFNS, OMIM 601321) is a rare RASopathy combining NF1 and Noonan syndrome features, usually caused by NF1 gene mutations, with cardiopathy, scoliosis, and intellectual disability comorbidities.
Neurogene Inc.
Neurogene Inc. is a New York-based clinical-stage biotechnology company founded in 2018 by Rachel McMinn that develops gene therapies for rare neurological diseases, led by NGN-401 for Rett syndrome.
Neurogenesis
Neurogenesis is the formation of new neurons from stem cells. Adult neurogenesis occurs in the mammalian dentate gyrus and subventricular zone; its existence and extent in adult humans remains actively disputed.
Neurogenetics
Neurogenetics is the field that studies the genetic basis of nervous system disorders, from monogenic diseases to polygenic conditions, underpinning diagnosis and therapy in neurology.
Neurogenic arthrogryposis multiplex congenita
Neurogenic arthrogryposis multiplex congenita (ORPHA:1143, OMIM 208100, 618766) is a rare autosomal recessive AMC subtype with neonatal onset, caused by motor neuron or peripheral nerve defects leading to fetal akinesia, multiple joint contractures, and neurogenic muscle atrophy; genes include DST, ZC4H2, DYNC1H1, KIF21A.
Neurogenic shock
Neurogenic shock: distributive shock from loss of sympathetic tone after spinal cord injury above T6, causing hypotension with bradycardia and warm skin; treated with fluids then norepinephrine to MAP targets.
Neurogenins
Neurogenins (NEUROG1, NEUROG2, NGN1/2) are atonal-related bHLH proneural transcription factors that determine neuronal fate in vertebrate placodes, cortex, spinal cord, and reprogramming.
Neurohypophysial hormone
Neurohypophysial hormones: vasopressin and oxytocin family nonapeptides made in the hypothalamus and released from the posterior pituitary, acting via V1a, V1b, V2, and oxytocin receptors.
Neuroimaging
Neuroimaging: imaging of brain structure and function using CT, MRI, fMRI, PET, SPECT, EEG, and MEG. Hemodynamic methods give millimeter spatial but seconds-scale temporal resolution; EEG/MEG give millisecond timing; fMRI has largely replaced PET in research.
Neuroinformatics
Neuroinformatics is a discipline combining neuroscience with informatics, building databases, computational models, and tools that let researchers share and analyze brain data across all scales.
Neurokinin A
Neurokinin A, also known as substance K or neuromedin L, is a mammalian tachykinin neuropeptide, 10 amino acids long, that excites neurons, dilates blood vessels, and contracts smooth muscle.