2,701 articles
ELEANOR trial
ELEANOR (NCT05438862) is a Czech-led randomized trial comparing early aortic valve surgery with watchful waiting in 217 asymptomatic severe aortic regurgitation patients at CMR-defined risk; distinct from a neratinib breast cancer study of the same name.
Electrical muscle stimulation
Electrical muscle stimulation (EMS, NMES): applying electric currents via electrodes to contract skeletal muscles for rehabilitation, muscle re-education, and atrophy prevention; conventional 20–40 Hz stimulation recruits motor units nonphysiologically, causing fatigue; FDA-regulated devices.
Electrical synapse
Electrical synapse (gap junction synapse): a neuron-to-neuron junction transmitting ionic current directly through connexin channels, mainly Cx36; fast, bidirectional, plastic, and about 20% of connections in C. elegans and rabbit retina circuits.
Electrocardiography in myocardial infarction
Electrocardiography in myocardial infarction (ECG in heart attack): use of the 12-lead ECG, within 10 minutes of first contact, to detect STEMI via ST-elevation criteria, guide reperfusion, and extend with posterior and right-sided leads.
Electrocorticography
Electrocorticography (ECoG) records brain electrical activity from electrodes on the cortical surface, used in epilepsy surgery and brain-computer interfaces; micro-ECoG arrays reach sub-millimeter resolution.
Electrodiagnosis
Electrodiagnosis (EDX medicine) evaluates nerve, muscle, and neuromuscular junction disorders via nerve conduction studies and needle EMG; distinct from EEG and ECG, it grew from Galvani's frog experiments and WWII nerve-injury studies.
Electroencephalography
Electroencephalography (EEG) records the brain's electrical activity via scalp electrodes. Pioneered by Hans Berger in 1924, it offers millisecond temporal resolution and is the cornerstone test for diagnosing epilepsy and sleep disorders.
Electroencephalography Phase Synchronization
Electroencephalography phase synchronization (EEG phase synchrony) is the uniform alignment of oscillation phases between neuronal groups in EEG, quantified by metrics such as the phase locking value, PLI, and wPLI, and read as a sign of brain integration in learning, memory, and perception.
Electromyography
Electromyography (EMG), an electrodiagnostic test recording muscle electrical activity at rest and during contraction, usually paired with nerve conduction studies to diagnose nerve and muscle disorders such as carpal tunnel syndrome and ALS.
Electrophysiology study
Electrophysiology study (EP study, invasive cardiac electrophysiology): catheter-based heart test recording electrical activity to locate arrhythmias, test drugs, map before ablation, and assess sudden cardiac death risk; 1-4 hours, mortality about 0.2%.
Elongated labia
Elongated labia, also called labia minora hypertrophy, are inner vaginal folds extending beyond the labia majora; a common nonpathologic anatomical variation, culturally valued in parts of Eastern and Southern Africa, and increasingly targeted by labiaplasty surgery.
Embolization
Embolization (embolotherapy): minimally invasive transcatheter occlusion of blood vessels using particles, liquids, coils, or gels to stop bleeding, starve tumors, or treat AVMs and aneurysms.
Emmetropia
Emmetropia, from Greek emmetros, is the normal refractive state of the eye: parallel rays focus on the relaxed retina, far point at infinity, opposite of ametropia, reached via emmetropization.
EMPHASIS-HF trial
EMPHASIS-HF, the Eplerenone in Mild Patients Hospitalization and Survival Study in Heart Failure, tested eplerenone in 2,737 patients with mild systolic heart failure and stopped early for benefit.
End-plate potential
End-plate potential (EPP), the graded depolarization of skeletal muscle at the neuromuscular junction, produced by acetylcholine release; built from about 200 quantal units (MEPPs, first recorded by Fatt and Katz), triggers the muscle action potential unless reduced, as in myasthenia gravis.
Endocardium
Endocardium: the endothelial innermost lining of the heart, continuous with vessel intima, with a subendocardium holding Purkinje fibers; embryonically from cardiac crescent mesoderm, it forms valves, septa, and conduction tissue.
Endochondral ossification
Endochondral ossification, also called intercartilaginous ossification, is one of the two modes of bone formation, in which a cartilage template is progressively replaced by bone, forming most bones of the mammalian skeleton.
Endocochlear potential and cochlear homeostasis
Endocochlear potential (EP), the ~+80 mV positive potential of cochlear endolymph generated by the stria vascularis via Kir4.1 channels, drives hair-cell transduction; its maintenance through potassium recycling defines cochlear homeostasis.
Endocrine gland
Endocrine glands are ductless organs, including the pituitary, thyroid, adrenals, and pancreas, that secrete hormones directly into the blood; the hypothalamic-pituitary axis regulates them by feedback, unlike ducted exocrine glands.
Endogenous cardiac stem cell
Endogenous cardiac stem cells (CSCs), heart-resident progenitors marked by c-Kit, Sca-1, Isl-1, once proposed for cardiomyocyte regeneration; lineage tracing showed negligible myogenic capacity, refuting the concept.
Endometrium
Endometrium (uterine lining): mucous membrane lining the uterus, with basal and functional layers, controlled by estradiol and progesterone; site of embryo implantation during the days 20-24 window of implantation and source of menstrual shedding.
Endophthalmitis
Endophthalmitis: purulent intraocular inflammation of vitreous and aqueous, usually infectious; exogenous or endogenous. Treated with intravitreal vancomycin and ceftazidime, with vitrectomy guided by the 1995 EVS trial.
Endorphins
Endorphins are endogenous opioid peptides, chiefly beta-endorphin from POMC, binding mu and other opioid receptors; discovered after the 1975 enkephalin finding, they modulate pain, reward, stress, and exercise effects.
Endothelium
Endothelium: the single layer of endothelial cells lining all blood vessels and lymphatics; term coined by Wilhelm His in 1865; a dynamic organ regulating vascular tone, permeability, hemostasis, inflammation, and angiogenesis, with dysfunction central to atherosclerosis.
Enlarged lymph nodes
Enlarged lymph nodes (lymphadenopathy) are abnormally sized or altered lymph nodes, >1 cm for most nodes. Usually benign and infectious; malignancy causes 1.1% of primary care cases, 4% over age 40.
Enteric nervous system
Enteric nervous system (ENS), the gut's "second brain": intrinsic network of over 500 million neurons and glia in the gastrointestinal wall, forming myenteric and submucosal plexuses, controlling motility and secretion autonomously of the CNS.
Enteric neuron
Enteric neuron, a neuron of the enteric nervous system ("second brain"), located in myenteric and submucosal plexuses; sensory, interneuron, motor, and secretomotor types operating largely independently of the CNS.
Entoptic phenomenon
Entoptic phenomenon: visual sensations arising inside the eye itself, including floaters, blue field entoptic phenomenon (Scheerer phenomenon), Haidinger's brushes, and the Purkinje tree; used clinically to measure macular blood flow.
Entorhinal cortex
The entorhinal cortex is a medial temporal lobe region acting as the gateway between the hippocampus and neocortex, central to memory and containing grid cells for navigation.
Enucleation of the eye
Enucleation of the eye is surgical removal of the entire globe, unlike evisceration (contents only) or exenteration (whole orbit). First documented by Bartisch in 1583; used for intraocular malignancy, blind painful eye, and trauma, usually with an orbital implant and later prosthesis.