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Intraductal papilloma of breast

Intraductal papilloma of breast (intraductal breast papilloma): benign wart-like growth in a milk duct, ages 35-55, causing nipple discharge. Solitary form does not raise cancer risk; multiple papillomas may; upgrade to carcinoma 5% benign, 36% atypical.

Intraductal tubulopapillary neoplasm of pancreas

Intraductal tubulopapillary neoplasm (ITPN) of the pancreas, also called intraductal tubule-papillary neoplasm, is a rare non-mucinous intraductal pancreatic tumor with high-grade dysplasia, MUC1/MUC6 positivity, invasive component in about 60%, and favorable post-surgical survival.

Intraepidermal squamous cell carcinoma

Intraepidermal squamous cell carcinoma, also called Bowen's disease or squamous cell carcinoma in situ, is a noninvasive skin cancer confined to the epidermis, with about 3% progression risk and treatments including 5-FU, PDT, cryotherapy, and excision.

Intraepithelial lymphocyte

Intraepithelial lymphocytes (IELs), also called intraepithelial T cells, are tissue-resident T cells wedged between epithelial cells of gut, skin, and airways; about 1 per 10 intestinal epithelial cells, mostly CD8+ TCRαβ or γδ, guarding the barrier and driving celiac disease.

Intraflagellar transport

Intraflagellar transport (IFT): bidirectional kinesin-2 and dynein-2 driven movement of IFT-A/IFT-B protein trains along ciliary microtubules, building and maintaining cilia; discovered in Chlamydomonas, linked to ciliopathies.

Intraflagellar transport protein 20

IFT20 (intraflagellar transport protein 20) is the smallest subunit of the IFT-B ciliary transport complex, part of the IFT-B2 peripheral subcomplex, uniquely localized at both cilia and the Golgi, where GMAP210 anchors it for ciliary protein sorting.

Intrafusal muscle fiber

Intrafusal muscle fiber: the small stretch-sensing fibers inside muscle spindles, in three types (bag1, bag2, chain), innervated by Ia/II afferents and dynamic/static gamma motoneurons for proprioception.

Intragastric administration

Intragastric administration is a drug delivery method in which a compound is introduced directly into the stomach of a laboratory rodent, most commonly by gavage, a feeding tube passed through the mouth.

Intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA, ICC) is the second most common primary liver cancer after HCC, arising proximal to second-order bile ducts; surgery is the only cure, with FGFR2/IDH1 targeted therapies for advanced disease.

Intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (obstetric cholestasis, ICP): pregnancy-specific liver disorder with pruritus and raised serum bile acids in late pregnancy. Graded mild 19–39, moderate 40–99, severe ≥100 µmol/L; UDCA and delivery timing vary by guideline.

Intralesional Infusions

Intralesional infusions (MeSH: Infusions, Intralesional) deliver medication directly into localized lesions via gravity flow or infusion pumps, distinct from intralesional injections; used in melanoma (T-VEC, PV-10), keloids, and skin disease.

Intralesional injection

An intralesional injection delivers medication directly into a skin lesion or other diseased tissue rather than the circulation, most often triamcinolone, a mainstay treatment for keloid scars and warts.

Oct 15, 2026

Intralinks

Intralinks, now part of SS&C Technologies, is a fintech company that pioneered the virtual data room in 1997 for secure document exchange in M&A deals.

Oct 20, 2026

Intralymphatic Injections

Intralymphatic injections deliver drugs or allergens directly into lymph nodes or lymphatic vessels (endolymphatic injection). Main use is intralymphatic immunotherapy (ILIT), three ultrasound-guided node injections replacing years of allergy shots, plus experimental cancer vaccine delivery.

Intramammary infusion

Intramammary infusion is a veterinary method of injecting a drug, usually an antibiotic, through the teat canal into a dairy cow's udder quarter to treat mastitis.

Intramedullary nail fixation

Intramedullary nail fixation is a surgical technique that stabilizes long-bone fractures with a metal rod in the marrow canal, the standard for femoral and tibial shaft fractures.

Intramedullary nailing

Intramedullary nailing is a surgical technique for fixing long-bone fractures in which a metal rod is inserted into the marrow canal and secured with locking screws.

Intramedullary screw fixation

Intramedullary screw fixation is an orthopedic technique that stabilizes unstable metacarpal and phalangeal fractures of the hand with a headless compression screw placed in the bone's medullary canal.

Intramuros

Intramuros, the Walled City of Manila, is the historic Spanish colonial core of the Philippines' capital, seat of the Galleon trade, now a heritage district managed by the Intramuros Administration.

Intramuscular fast-flow vascular anomaly

Intramuscular fast-flow vascular anomaly (IM-FFVA), formerly intramuscular capillary-type hemangioma, is a rare fast-flow lesion within skeletal muscle carrying somatic MAP2K1 or KRAS mutations, treated mainly by complete surgical resection.

Intramuscular injection

An intramuscular injection delivers medication deep into a muscle, bypassing liver metabolism and absorbing faster than subcutaneous routes; common sites are the deltoid and thigh.

Intranasal administration

Intranasal administration is a drug delivery route giving medication through the nose as a spray, drops, gel, or powder, offering rapid onset that avoids hepatic first-pass metabolism.

Intranet

An intranet, or internal network, is a private computer network based on Internet technology that organizations use to share information among employees, protected by firewalls and typically accessed via LAN or VPN.

Oct 22, 2026

Intransigent Radical Civic Union

The Intransigent Radical Civic Union (Unión Cívica Radical Intransigente, UCRI) was an Argentine political party, created in 1957 from the split of the Radical Civic Union.

Intransitive verb

Intransitive verb: a verb taking no direct object (e.g. arrive, laugh, fall). Covers ambitransitive verbs, the unergative/unaccusative split from Perlmutter 1978, diagnostics, and passive restrictions.

Intraocular administration

Intraocular administration is a drug delivery route in which medication is injected directly into compartments of the eye, most commonly the vitreous cavity, to treat retinal disease.

Intraocular injection

Intraocular injection is a clinical procedure that delivers a drug directly into the eye to treat retinal diseases, minimizing systemic absorption; intravitreal injection is the most common form.

Intraocular lens

An intraocular lens (IOL), also called an intraocular implant, is an artificial lens implanted in the eye to replace the natural lens after cataract removal.

Intraocular lens implantation

Intraocular lens implantation is the surgical placement of an artificial lens inside the eye, replacing the natural lens removed during cataract surgery or correcting refractive error.