72,234 articles
Home Parenteral Nutrition
Home total parenteral nutrition (HPN) delivers complete intravenous nutrition at home via a central catheter for chronic intestinal failure. Pioneered in the late 1960s by Scribner, Shils, and Dudrick; about 32,000 US users annually; survival depends on underlying disease.
Home spirometry
Home spirometry is forced expiratory lung function testing performed by patients at home with portable spirometers, mainly to monitor asthma, COPD, cystic fibrosis, and lung transplant function.
Homemaker Services
Homemaker services are non-medical assistance at home, such as meal preparation and bathing, delivered by trained aides to help ill, disabled, or recovering people manage daily living.
Homeobox
Homeobox: a 180-nucleotide DNA sequence encoding the 60-amino-acid homeodomain, a helix-turn-helix DNA-binding motif in developmental transcription factors such as Hox genes, first discovered in Drosophila in 1983.
Homeobox expressed in ES cells 1
Homeobox expressed in ES cells 1 (HESX1), formally HESX homeobox 1, is a human gene on chromosome 3 encoding a transcriptional repressor essential for forebrain and pituitary development.
Homeobox protein
Homeobox protein: transcription factor encoded by a homeobox gene, containing a ~60-amino-acid homeodomain DNA-binding domain. Includes Hox proteins patterning animal body axes; discovered 1984 in Drosophila; distinct from homeobox genes generally.
Homeobox protein orthopedia
Homeobox protein orthopedia (OTP, orthopedia homeobox) is a homeodomain transcription factor on human chromosome 5q14.1, essential for neuroendocrine hypothalamus development, linked to obesity via MC4R, and used as a lung carcinoid marker.
Homeodomain
Homeodomain: a conserved 60-amino-acid helix-turn-helix DNA-binding domain encoded by the ~180-bp homeobox, discovered in Drosophila in 1984; found in transcription factors across eukaryotes, central to development and disease.
Homeodomain-only protein
Homeodomain-only protein, also called HOPX or HOP, is an atypical human homeodomain protein that cannot bind DNA, instead regulating transcription through partners such as serum response factor.
Homeopathic dilutions
Homeopathic dilutions (potentizations): serial 1:10 (X/D) or 1:100 (C) dilutions with succussion or trituration, introduced by Hahnemann; 12C is the Avogadro limit, 30C equals a 10^60 dilution, and no FDA-approved homeopathic product exists.
Homeopathy
Homeopathy: alternative medical system founded by Samuel Hahnemann in Germany around 1800, based on "like cures like" and extreme dilution; reviews find no reliable evidence of effectiveness and no FDA-approved homeopathic products exist.
Homeostasis
Homeostasis is the maintenance of dynamic equilibrium of internal conditions such as temperature, glucose, and blood pressure, via negative feedback loops around set points; defined by Walter Cannon in 1929, critiqued and extended by allostasis.
Homeostatic chondrocyte
Homeostatic chondrocyte (HomC, CL:0020020), a single-cell-RNA-seq-defined chondrocyte state enriched in homeostasis and circadian clock pathways; markers DDIT3, ATF3, GDF15; depleted in osteoarthritic cartilage.
Homeostatic model assessment
Homeostatic model assessment (HOMA) is a mathematical method that estimates insulin resistance and beta-cell function from a single fasting blood sample, widely used in diabetes research since 1985.
Homer family
Homer family (Homer1, Homer2, Homer3; Vesl) proteins: postsynaptic density adaptor proteins binding mGluR1/5, IP3 receptors, and Shank via EVH1 domains; long forms multimerize, short Homer1a is an activity-induced dominant negative.
Homer Smith (renal physiologist)
Homer Smith (1895–1962) was an American renal physiologist at New York University whose inulin and PAH clearance methods made kidney function measurable in patients, winning the 1947 Lasker Award.
Homez, homeobox domain
HOMEZ (KIAA1443), homeobox and leucine zipper encoding, is a vertebrate gene at 14q11.2 encoding a 550-aa nuclear transcription factor with three atypical homeodomains, two leucine zippers, and an acidic domain, related to the ZHX family.
Homing and trail-following in gastropods
Homing and trail-following in gastropods is the return of snails and limpets to fixed home refuges and their tracking of mucus trails, based on chemical detection of pedal mucus.
Homing endonuclease
Homing endonuclease, also called meganuclease: intron- or intein-encoded site-specific nuclease (families LAGLIDADG, HNH, GIY-YIG, His-Cys box, PD-(D/E)XK) that drives selfish DNA homing via double-strand breaks; used in genome editing, gene therapy, and vector control.
Homing pigeon
Homing pigeon (Columba livia domestica), domesticated bird bred to return to its loft from distant release points; navigates with sun compass, magnetic compass, and olfactory map; long used for military messaging.
Hominidae
Hominidae (great apes), family of primates including orangutans, gorillas, chimpanzees, bonobos, and humans; formerly humans only, with other apes in Pongidae; Miocene fossil record, African or Eurasian origins debated.
Homininae
Homininae (African apes), subfamily of Hominidae named by Gray 1825, contains Gorilla, Pan, and Homo; sister to Ponginae (orangutans), divided into tribes Gorillini, Panini, Hominini, with human-chimp-gorilla divergences dated roughly 4-12 Mya.
Hominini
Hominini (hominins) is the tribe containing humans and fossil taxa closer to humans than to chimpanzees (Pan); divergence about 6 Ma; includes Sahelanthropus, Orrorin, Ardipithecus, Australopithecus, Paranthropus, Homo; scope of Pan inclusion disputed.
Hominy
Hominy: dried corn kernels treated with an alkali (lye or limewater) via nixtamalization, removing the hull; the Nahuatl-derived nixtamal. Basis of pozole, menudo, grits, and masa; adds calcium and improves niacin bioavailability.
Homo
Homo is the human genus, sole surviving member Homo sapiens, spanning ~2–3 million years with about fifteen proposed species including H. erectus, H. habilis, H. neanderthalensis, H. floresiensis, and H. naledi.
Homo antecessor
Homo antecessor, an extinct Early Pleistocene human species from Gran Dolina, Atapuerca, Spain, named in 1997; oldest known Western European hominin (~800,000 years), with evidence of cannibalism and a proteome placing it as sister to the Neanderthal-modern human ancestor.
Homo erectus
Homo erectus, also called Java Man or Peking Man, is an extinct human species living about 1.89 million to 110,000 years ago, the first known to leave Africa, with Acheulean handaxes and debated fire use.
Homo ergaster
Homo ergaster is the name many paleoanthropologists give early African Homo erectus, about 2.0 to 1.4 million years ago, the first humans with modern body proportions, known from Turkana Boy, Acheulean tools, and debated fire use.
Homo floresiensis
Homo floresiensis, the "hobbit", an extinct small-brained human species found only at Liang Bua cave, Flores, Indonesia; discovered 2003, LB1 female 106 cm tall, 417 cm3 brain, lived about 100,000-50,000 years ago.
Homo habilis
Homo habilis, "handy man," an early human species of eastern and southern Africa, 2.4–1.4 million years ago; named 1964 by Leakey, Tobias, and Napier from Olduvai Gorge fossils; debated placement in genus Homo.