72,234 articles
Hyperzincemia and hypercalprotectinemia
Hyperzincemia and hypercalprotectinemia (Hz/Hc, AICZC, PAMI syndrome) is a rare PSTPIP1 (E250K, E257K) autoinflammatory disorder with high blood zinc and calprotectin, cytopenia, hepatosplenomegaly, and skin and joint inflammation.
Hypha
Hypha (plural hyphae): the tubular filament that is the structural unit of fungi, growing by apical tip growth via the Spitzenkörper, branching to form mycelium; distinct from pseudohyphae and yeast forms.
Hyphaene
Hyphaene (doum palms), genus of dioecious coryphoid palms native from tropical and southern Africa to Sri Lanka, unique for dichotomously branching trunks; about 8 species, edible fruits, Eocene origin, difficult taxonomy with many synonyms.
Hyphaene thebaica
Hyphaene thebaica, the doum or gingerbread palm (دوم), is a branching dioecious African palm from West Africa to Arabia, with hard edible fruits rich in fiber, potassium, and phenolics, sacred in ancient Egypt.
Hyphal cell
Hyphal cell: a cell of a fungal hypha, the filament of a mycelium. Grows by apical tip growth via the Spitzenkörper, is compartmentalized by septal pores and Woronin body plugs, and underlies fungal multicellularity and dimorphism.
Hyphema
Hyphema is blood in the eye's anterior chamber, usually from blunt trauma; graded 0–IV (microhyphema to eight-ball), complicated by rebleeding, raised intraocular pressure, and corneal blood staining.
Hypnagogia
Hypnagogia is the transitional consciousness state at sleep onset (N1), marked by hypnagogic hallucinations; terms from Maury (1848), Myers (hypnopompic), Mavromatis (1983); common in the general population and narcolepsy, and studied for creativity via MIT's Dormio dream incubation.
Hypnales
Hypnales, the largest order of mosses (about 4,200 species), pleurocarpous feather and fern mosses; formerly included Leucodontales and Hypnobryales; rapid early radiation, Gondwanan origin, sister order Hookeriales.
Hypnic headache
Hypnic headache, or "alarm clock" headache, is a rare primary headache disorder first described by Raskin in 1988: sleep-only attacks waking patients, lasting 15 minutes to 4 hours, treated with lithium, caffeine, melatonin, or indomethacin.
Hypnic jerk
Hypnic jerk, also called sleep start or hypnagogic jerk: a brief involuntary myoclonic muscle contraction at sleep onset, stage N1, with falling sensation; affects about 70% of people, triggered by stress, caffeine, and sleep deprivation.
Hypnodendrales
Hypnodendrales (Bell, Newton & Quandt, 2007) is an order of pleurocarpous mosses in superorder Hypnanae, sister to Ptychomniales, Hookeriales, and Hypnales; families include Hypnodendraceae, Racopilaceae, Pterobryellaceae, with mainly tropical, Gondwanan distribution.
Hypnopompic hallucinations
Hypnopompic hallucinations are vivid, often visual, dream-like hallucinations that occur on waking from sleep. They are common, and frequent episodes, especially with sleep paralysis, can point to narcolepsy.
Hypnosis
Hypnosis, also known as hypnotism, is a state of concentrated attention with reduced awareness of surroundings and heightened responsiveness to suggestion, first named in 1843.
Hypnotherapy
Hypnotherapy is the therapeutic use of hypnosis via induction and suggestion. Rooted in Mesmerism, named by Braid in 1843; best evidence for gut-directed IBS treatment, weaker for smoking cessation.
Hypnotic
Hypnotic: sleep-inducing drug class for insomnia, also called sedative-hypnotics; spans barbiturates, benzodiazepines, Z-drugs, melatonin agonists, and orexin antagonists, with CBT-I preferred first-line.
HYPNOVRNEO trial
The HYPNOVRNEO trial was a randomized controlled trial in Rennes, France, testing whether six 10-minute virtual reality hypnosis sessions during work breaks reduced stress and compassion fatigue among NICU nurses.
Hypnum
Hypnum, a genus of pleurocarpous mosses in Hypnaceae typified by Hypnum cupressiforme (cypress-leaved plaitmoss). Once defined by falcate leaves and a short double costa, molecular work showed it polyphyletic; now restricted to the H. cupressiforme complex, widely used in metal biomonitoring.
HYPO-5 trial
HYPO-5 (NCT05786742) is a phase 1-2 CHU de Québec trial comparing 25 Gy/5-fraction ultra-hypofractionated prostate radiotherapy plus a 15 Gy HDR brachytherapy boost against moderately hypofractionated schedules, reporting interim safety and biochemical control.
Hypo-OPRA trial
Hypo-OPRA (NCT06991465) is a phase II single-arm McGill trial testing 25 Gy in 5 fractions plus a boost to 35 Gy with FOLFOX or capecitabine for rectal preservation in locally advanced rectal adenocarcinoma.
Hypoactive sexual desire disorder
Hypoactive sexual desire disorder (HSDD), also called female sexual interest/arousal disorder in DSM-5, is persistent low sexual desire causing marked distress. Covers diagnosis, prevalence (8–10% of women), mechanisms, flibanserin, bremelanotide, testosterone, and controversy.
Hypoalbuminemia
Hypoalbuminemia, low serum albumin below 35 g/L, is a common hospital finding driven mainly by inflammation and protein loss, a strong mortality predictor, and a poor nutrition marker; albumin infusion has few supported indications.
Hypoaldosteronism
Hypoaldosteronism (ICD-11 5A73) is deficient aldosterone production or action, causing hyperkalemia, hyponatremia, and acidosis. Forms include hyporeninemic hypoaldosteronism, CYP11B2 aldosterone synthase deficiency, and pseudohypoaldosteronism; treated with fludrocortisone or sodium supplementation.
Hypoallergenic dog breed
Hypoallergenic dog breed: a label for low-shedding breeds like Poodle and Labradoodle; studies of Can f 1 show no breed is truly hypoallergenic, allergen output varies by individual dog.
Hypoaspis
Hypoaspis is a genus of Laelapidae mites (Mesostigmata) described by Canestrini in 1884, once a broad catch-all genus now restricted to about 36 soil predatory species; its former members include the biocontrol mites Gaeolaelaps aculeifer and Stratiolaelaps scimitus.
Hypocalcemia
Hypocalcemia, or low blood calcium, is an abnormally low serum calcium level caused by hypoparathyroidism, vitamin D deficiency, or kidney disease, treatable with calcium and vitamin D.
Hypocalcemic vitamin D-dependent rickets
Hypocalcemic vitamin D-dependent rickets (VDDR type 1, VDDR1A/VDDR1B; 1-alpha-hydroxylase deficiency) is a rare autosomal recessive disorder of vitamin D activation causing infantile hypocalcemia and rickets, treated with calcitriol.
Hypocalcemic vitamin D-resistant rickets
Hypocalcemic vitamin D-resistant rickets (HVDRR, VDDR2A, OMIM 277440) is a rare autosomal recessive rickets caused by VDR gene mutations, causing calcitriol resistance, hypocalcemia, elevated calcitriol, and alopecia in about half to two-thirds of patients.
Hypocalciuria
Hypocalciuria (low urinary calcium; ICD-11 MF98.3), also called low urine calcium. Key causes: familial hypocalciuric hypercalcemia (CASR, GNA11, AP2S1 mutations), thiazides, lithium, vitamin D deficiency; CCCR <0.01 suggests FHH over primary hyperparathyroidism.
Hypocapnia
Hypocapnia, also called hypocarbia, is an arterial CO2 partial pressure below 35 mm Hg (normal 35-45), usually from hyperventilation, causing respiratory alkalosis and cerebral vasoconstriction; transiently lifesaving for intracranial hypertension but harmful when prolonged.
Hypochondriasis
Hypochondriasis: persistent preoccupation with having serious illness despite reassurance; DSM-IV somatoform diagnosis, split by DSM-5 into illness anxiety disorder and somatic symptom disorder, retained in ICD-11.