72,234 articles
STIL
STIL (SCL/TAL1 interrupting locus, SIL) is a human gene at 1p33 encoding a centriole duplication protein, ortholog of SAS-5/ANA-2. Knockout mice lack centrioles and cilia and die midgestation; truncating mutations cause autosomal recessive primary microcephaly MCPH7.
Stillbirth
Stillbirth, also called fetal demise, is the death of a baby before or during birth, at or beyond 22 weeks of pregnancy according to the World Health Organization.
Stimulant
Stimulants, also known as psychostimulants, are drugs that boost brain chemicals to increase alertness, attention, and energy, ranging from caffeine to prescription drugs that treat ADHD and narcolepsy.
Stimulant psychosis
Stimulant psychosis: drug-induced delusions and hallucinations from amphetamine, methamphetamine, cocaine, or prescription stimulants; affects 36.5% of methamphetamine users versus 0.2% of therapeutic users; usually transient, 19–33% transition to primary psychosis.
Stimulated Raman scattering histology
Stimulated Raman scattering histology (SRH) is a label-free optical imaging method producing histology-like images of unprocessed surgical tissue, developed for brain tumor diagnosis in the operating room.
Stimuli-responsive nanoparticles
Stimuli-responsive nanoparticles are drug-delivery particles that release cargo in response to triggers like pH, redox state, enzymes, light, ultrasound, or heat, aiming to boost efficacy and cut toxicity.
Stimulus (physiology)
Stimulus (physiology): a detectable environmental or internal change (light, sound, chemical, temperature, pressure) that activates sensory receptors. Key facts: transduction into graded receptor potentials, coding of modality, location, intensity, duration, and receptor adaptation.
Stimulus control
Stimulus control is a behavioral technique in which environmental cues are arranged so a desired behavior occurs reliably, central to behavior therapy, applied behavior analysis, and insomnia treatment.
STING-associated vasculopathy with onset in infancy
STING-associated vasculopathy with onset in infancy (SAVI) is a rare genetic autoinflammatory disease, first described in 2014, causing severe skin lesions and progressive lung disease in infants.
STING1
STING1 (formerly TMEM173; protein STING, ERIS, MITA, MPYS) is the human gene at 5q31.2 encoding the ER adaptor that binds cGAMP from cGAS, drives TBK1/IRF3 type I interferon signaling, and whose mutations cause SAVI vasculopathy.
Stinger
Stinger: venom-injecting organ of bees, wasps, hornets, fire ants, and scorpions; in Hymenoptera a modified ovipositor, in honeybees barbed and autotomized to keep pumping venom.
Stinging of skin
Stinging of skin (ICD-11 ME65.3) is an unpleasant nettle-like cutaneous sensation triggered by topical preparations or stimuli most people tolerate, the hallmark of sensitive skin syndrome, tested with the lactic acid sting test and linked to small-fiber neuropathy and TRPV1.
Stingless bee
Stingless bees (Meliponini), also called meliponines, are over 500 social bee species of tropical regions with atrophied stings; they store honey in cerumen pots, produce acidic high-moisture honey, and are kept in meliponiculture since Maya times.
Stingless bee colony organization and life cycle
Stingless bee colonies are perennial eusocial nests with one dominant queen and thousands of workers, founded by swarming fission, with slow larval development of about 50 days.
Stingless bee communication and behavior
Stingless bees (Meliponini) recruit nestmates to food using pheromone trails, odor marks, and vibration rather than honeybee waggle dances, with signaling strategies varying widely between species.
Stingless bee honey
Stingless bee honey, often called pot-honey, is honey produced by stingless bees and stored in small cerumen pots; it is more acidic, more watery, and far rarer than honeybee honey.
Stingless bee nest architecture
Stingless bee nest architecture is the enclosed structure built by Meliponini bees: horizontal brood combs surrounded by an involucrum, with oval storage pots built outside it.
Stingray
Stingray (Myliobatoidei): flattened, venomous-barbed cartilaginous fish of shallow coastal seas, up to 6.5 ft and 790 lb, with ampullae of Lorenzini prey sensing; distinct from manta, eagle, and electric rays.
Stingray injury
A stingray injury is a wound from the barbed, venomous tail spine of a stingray, usually on the feet or lower legs of people wading in shallow water.
Stinkhorn and nidularioid ecology and dispersal
Stinkhorn and nidularioid ecology and dispersal covers how gasteroid fungi spread spores they cannot launch themselves: stinkhorns lure insects with carrion-like odors, while bird's-nest fungi eject spore packets with raindrops.
STIP1
STIP1 (Hop/Sti1, stress induced phosphoprotein 1) is a human co-chaperone gene encoding an adaptor that bridges Hsp70 and Hsp90, stimulating Hsp70 ATPase and inhibiting Hsp90 ATPase during client protein folding; secreted Hop also signals via prion protein and is implicated in cancer and neurodegeneration.
Stipa
Stipa (feather grasses, needlegrasses) is a Poaceae genus of perennial tussock grasses with twisted, hygroscopic awns; about 141 accepted Old World species, centered in Middle Asian steppes, type species S. pennata.
Stiripentol
Stiripentol (Diacomit) is a third-generation antiseizure medication, a GABAergic and CYP-inhibiting dioxolane approved from 2007 (EU) and 2018 (FDA) as add-on to clobazam and valproate for refractory tonic-clonic seizures in Dravet syndrome.
Stirred-tank bioreactor
A stirred-tank bioreactor is a cylindrical vessel whose rotating impellers mix a liquid culture while a bottom sparger supplies oxygen, serving microbial fermentation and mammalian cell culture.
STK11
STK11 (LKB1, liver kinase B1) is a tumor suppressor serine/threonine kinase gene on 19p13.3; germline mutations cause Peutz-Jeghers syndrome, and somatic loss is common in lung cancer.
STK38
STK38 (NDR1), human serine/threonine kinase of the AGC NDR/LATS family on chromosome 6p21.31; Hippo pathway YAP kinase and LATS inhibitor, autophagy regulator, XPO1 activator, cancer-relevant.
STK39
STK39 (SPAK) is a human serine/threonine kinase gene at 2q24.3 linking WNK kinases to NCC/NKCC cotransporters, renal salt handling, and blood pressure; also implicated in HCC inflammation, DNA repair, and PARP inhibitor resistance.
STK4
STK4 (MST1, KRS2, YSK3) is a human chromosome 20 gene encoding a 487-aa serine/threonine kinase of the Hippo pathway; biallelic loss causes autosomal recessive combined immunodeficiency with lymphopenia and EBV-driven lymphoproliferation.
STMN1
STMN1 (stathmin 1, oncoprotein 18) is a human cytosolic phosphoprotein gene that destabilizes microtubules by sequestering tubulin dimers; overexpression marks poor prognosis in most solid tumors and modulates paclitaxel and vincristine sensitivity. Distinct from SMN1 and STNM01.
Stoat
Stoat (Mustela erminea), also called ermine or short-tailed weasel: a circumpolar mustelid with a black-tipped tail and white winter coat. Least Concern globally, but a devastating invasive predator of native birds in New Zealand.