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Ectasia of the left atrial appendage
Ectasia of the left atrial appendage, also known as left atrial appendage aneurysm, is a rare cardiac malformation enlarging the left auricle, usually without other cardiac lesions.
Ecteinascidia turbinata
Ecteinascidia turbinata, the mangrove tunicate, is a colonial Perophoridae ascidian of warm Atlantic and Mediterranean seas, source of the anticancer drug trabectedin (ET-743, Yondelis) actually produced by its endosymbiont Candidatus Endoecteinascidia frumentensis.
Ecthyma
Ecthyma (ICD-11 1B73) is a superficial ulcerative bacterial pyoderma with punched-out crusted ulcers, caused by beta-hemolytic streptococci and Staphylococcus aureus; ecthyma gangrenosum is its Pseudomonas aeruginosa sepsis variant.
Ecthyma gangrenosum
Ecthyma gangrenosum, a necrotizing skin infection with hemorrhagic pustules evolving into black eschars, classically marks Pseudomonas aeruginosa bacteremia in immunocompromised, neutropenic patients, though other bacteria and fungi can cause identical lesions.
Ectoderm
Ectoderm: outermost of the three embryonic germ layers, formed at gastrulation; gives rise to epidermis, nervous system, neural tube, and neural crest. Also called ectodermal layer; basis of ectodermal dysplasias.
Ectodermal cell
Ectodermal cell, a cell of the ectoderm germ layer; gives rise to nervous system, epidermis, and neural crest derivatives; fate set by BMP signaling during gastrulation.
Ectodermal dysplasia
Ectodermal dysplasia (ED), also called anhidrotic or hypohidrotic ectodermal dysplasia, Christ-Siemens-Touraine syndrome: a group of 180+ inherited disorders of ectoderm-derived tissues (hair, teeth, nails, sweat glands), affecting about 1 in 5,000-10,000 people; HED from EDA gene mutations is the most common type.
Ectodermal dysplasia-skin fragility syndrome
Ectodermal dysplasia-skin fragility syndrome (McGrath syndrome, EBS due to plakophilin deficiency) is a rare autosomal recessive PKP1 genodermatosis with neonatal skin fragility, palmoplantar keratoderma, nail dystrophy, alopecia, and no cardiac involvement.
Ectoine
Ectoine, a zwitterionic tetrahydropyrimidine compatible solute discovered in 1985 in Ectothiorhodospira halochloris, protects microbes against osmotic, heat, cold, and desiccation stress; produced industrially and used in atopic dermatitis creams and cryopreservation.
Ectomycorrhiza
Ectomycorrhiza (ECM), also called ectomycorrhizal symbiosis, is a fungus-root partnership marked by a mantle and Hartig net, trading soil nitrogen for plant carbon in most temperate and boreal forest trees.
Ectopia cordis
Ectopia cordis, or ectopic heart, is a rare congenital defect in which the heart lies partly or wholly outside the thorax through an anterior chest wall defect; prevalence 5.5–7.9 per million births, often with pentalogy of Cantrell, survival about 10%.
Ectopic anus
Ectopic anus (anal ectopia, misplaced anus), ICD-11 LB17.1: congenital abnormal displacement of the anus, usually anterior, causing constipation; female-predominant, treated by anoplasty, distinct from perineal fistula.
Ectopic or pelvic kidney
An ectopic kidney, including the pelvic kidney, is a congenitally displaced kidney caused by failed upward migration during fetal development, affecting roughly 1 in 1,000 people.
Ectopic pregnancy
An ectopic pregnancy, also called a tubal or extrauterine pregnancy, is one that implants outside the uterus, usually in a fallopian tube, and can cause life-threatening rupture.
Ectopic testis
Ectopic testis (ICD-11 LB52.0), a form of cryptorchidism in which the testis lies outside its normal descent path, most often in the superficial inguinal pouch; requires orchidopexy, usually before 12 months.
Ectopic thymus
Ectopic thymus, also called ectopic cervical or intrathyroidal thymus, is thymic tissue stranded along the embryological descent path from the third pharyngeal pouch; a benign pediatric neck or thyroid finding that can mimic cancer.
Ectoplasm (paranormal)
Ectoplasm (paranormal), also called teleplasm or ideoplasm, is a substance supposedly exuded by spiritualist mediums in trance, coined by Charles Richet in 1894; every analyzed sample proved to be cloth, paper, or other props.
Ector County
Ector County, Texas: West Texas county created 1887 from Tom Green County, named for Mathew D. Ector; seat Odessa, a Permian Basin oil center and the Odessa MSA, population about 173,800 (2025).
Ector County Independent School District
Ector County Independent School District (ECISD), Odessa, Texas public school district created August 18, 1921 by House Bill 59; now 42 schools, 33,000+ students, led by Superintendent Dr. Keeley Boyer.
Ectotherm
Ectotherm: an animal relying on external heat sources rather than metabolic heat to regulate body temperature; also called cold-blooded. Key contrasts with endotherms: 4–15x lower resting energy use, behavioral thermoregulation, thermal performance limits.
Ectrodactyly
Ectrodactyly, or split hand/foot malformation (SHFM), cleft hand, is a congenital central-ray limb deficiency causing missing central fingers or toes; typical (V-shaped, genetic, bilateral) versus atypical (U-shaped, sporadic) forms, TP63/DLX/WNT10B genes, EEC syndrome association.
Ectropion of eyelid
Ectropion of the eyelid: outward turning of the eyelid margin, usually the lower lid, exposing the inner surface. Main types involutional, cicatricial, mechanical, paralytic; treated with lubricants and lateral tarsal strip surgery.
ECTS grading scale
The ECTS grading scale was a letter-based A–E scale ranking passing students by their position in the cohort; it was replaced in 2009 by the ECTS grading table.
ECU-Test
ECU-Test, or ecu.test, is test automation software developed by tracetronic GmbH of Dresden, Germany, that creates, executes, and evaluates tests of automotive electronic control unit software across all development stages.
Ecuador
Ecuador, a northwestern South American country on the equator with capital Quito, spans Andes, Amazon, coast, and Galápagos Islands; dollarized since 2000, oil- and banana-exporting, biodiverse, and facing a severe organized-crime security crisis.
Ecuador national football team
Ecuador national football team, La Tri, CONMEBOL men's side; five World Cups (2002, 2006, 2014, 2022, 2026), Round of 16 in 2006 and 2026, second in 2026 qualifying with five goals conceded, coach Sebastián Beccacece.
Ecuadorian Agrarian Reform of 1964
The Ecuadorian Agrarian Reform of 1964 was a land reform enacted by Ecuador's military junta on 11 July 1964, abolishing the huasipungo system of servile labor on Andean haciendas.
Ecuadorian Agrarian Reform of 1973
The Ecuadorian Agrarian Reform of 1973, decreed by General Guillermo Rodríguez Lara's military government on 9 October 1973, broadened the 1964 law and required owners to exploit over 80 percent of their land.
Ecuadorian Civil War of 1859–1860
The Ecuadorian Civil War of 1859–1860 was an internal conflict in which Ecuador fragmented into four rival governments while Peru blockaded its coast, ending in September 1860.
Ecuadorian conflict (2024–present)
Ecuadorian conflict (2024–present), also called Ecuador's internal armed conflict: President Daniel Noboa's January 2024 declaration of war on 22 drug gangs including Los Choneros and Los Lobos, its contested legal status, homicide trends, and human rights record.