All articles starting with R
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Rh(III)-catalyzed C–H activation
Rh(III)-catalyzed C–H activation is a family of organic reactions in which cationic Cp*Rh(III) complexes cleave otherwise inert carbon–hydrogen bonds and couple them with unsaturated partners to form C–C and C–heteroatom bonds directly, without pre-functionalized starting materials.
Rh(III)-catalyzed C–H annulation
Rh(III)-catalyzed C–H annulation is an organic reaction in which a Cp*Rh(III) catalyst cleaves a C–H bond and couples it with an alkyne to form a ring.
Rh(III)-catalyzed C–H annulation with alkynes
Rh(III)-catalyzed C–H annulation with alkynes is a reaction class in which a cyclopentadienyl rhodium(III) catalyst activates a directed C–H bond and inserts an alkyne to close a ring, building fused heterocycles.
Rh18
Rh18, also called SJRH-18, is a human rhabdomyosarcoma cell line established at St. Jude Children's Research Hospital from a two-year-old girl's perineal tumor, used widely in pediatric sarcoma research.
Rh28
Rh28 (SJRH-28, CVCL_8752) is a human alveolar rhabdomyosarcoma cell line from a 17-year-old male, PAX3-FOXO1 fusion-positive, near tetraploid, established via xenograft at St. Jude in 1987, notable for spontaneous senescence and use in PPTP drug testing.
Rh30
Rh30 (SJCRH30, RMS13, CVCL_0041) is a human alveolar rhabdomyosarcoma cell line from a bone marrow metastasis, carrying the PAX3-FOXO1 fusion, TP53 mutations, and 12q13-q15 CDK4 amplification; distributed by ATCC and DSMZ.
Rh4
Rh4 (RH4, SJRH-4, CVCL_5916) is a human alveolar rhabdomyosarcoma cell line from a 7-year-old girl's lung metastasis, PAX3-FOXO1 fusion-positive with TP53 mutation, paired with RH41 from the same patient.
RH5 (robot)
RH5 is a full-size humanoid robot developed by the German Research Center for Artificial Intelligence (DFKI) in Bremen, Germany, standing 2 m tall and weighing about 62.5 kg.
Rhabditida
Rhabditida, also called Strongylida in NCBI synonymy, is an order of Chromadorea nematodes with about 450 genera, including C. elegans, soil rhabditids, and the entomopathogenic genera Steinernema and Heterorhabditis.
Rhabdoid tumor
Rhabdoid tumor (malignant rhabdoid tumor), an aggressive infant/childhood cancer of kidney, CNS (ATRT), and soft tissues, driven by SMARCB1 loss; 5-year survival about 20%, treated with surgery, chemotherapy, radiotherapy.
Rhabdoid tumor predisposition syndrome
Rhabdoid tumor predisposition syndrome (RTPS, RTPS1/RTPS2) is a rare autosomal dominant hereditary cancer syndrome caused by germline SMARCB1 or SMARCA4 variants, predisposing infants to aggressive rhabdoid tumors (ATRT, kidney, soft tissue) with over 90% penetrance by age 5.
Rhabdomyolysis
Rhabdomyolysis: rapid skeletal muscle breakdown releasing myoglobin and creatine kinase, causing acute kidney injury. Causes include crush injury, statins, exertion, infections; treated with early IV fluids.
Rhabdomyoma
Rhabdomyoma: benign skeletal-muscle tumor, cardiac and extracardiac (adult, fetal, genital) types. Cardiac form is the most common pediatric heart tumor, linked to tuberous sclerosis, regresses spontaneously; mTOR inhibitors shrink it.
Rhabdomyosarcoma
Rhabdomyosarcoma (RMS), also called embryonal or alveolar rhabdomyosarcoma, is the most common childhood soft tissue sarcoma, arising in striated muscle. Key facts: PAX3/7-FOXO1 fusions mark alveolar RMS; treated with VAC/IVA chemotherapy, surgery, and radiation.
Rhabdomyosarcoma of the cervix uteri
Rhabdomyosarcoma of the cervix uteri, a rare embryonal (usually botryoid/polypoid) skeletal-muscle cancer of the cervix, peaks in the second decade, is treated with chemotherapy plus conservative surgery, and has the best survival among gynecologic rhabdomyosarcoma sites.
Rhabdomyosarcoma of the corpus uteri
Rhabdomyosarcoma of the corpus uteri (uterine rhabdomyosarcoma) is an extremely rare, highly malignant uterine sarcoma from primitive mesenchymal cells with skeletal muscle differentiation, presenting with abnormal bleeding, linked to DICER1, and treated with surgery plus VAC chemotherapy.
Rhabdomys
Rhabdomys, the African striped mice or four-striped grass mice, is a genus of small (40-50 g) diurnal murid rodents of southern and eastern Africa, defined by four dorsal stripes formed through Alx3 repression of Mitf and by socially flexible solitary or group living.
Rhabdophis
Rhabdophis, Asian keelback snakes (34 species, East and South Asia), known for nuchal glands storing bufadienolide toxins sequestered from toads or fireflies; some species are both venomous and poisonous.
Rhabdopleura
Rhabdopleura (Allman, 1869) is the only living graptolite genus, a colonial pterobranch hemichordate with stolon-connected zooids in secreted tubes, a Middle Cambrian to Eocene fossil record, and 12 described extant species.
Rhabdoviridae
Rhabdoviridae: family of bullet-shaped, enveloped negative-sense ssRNA viruses (order Mononegavirales) with 580 species in 62 genera and four subfamilies; includes rabies virus (Lyssavirus), vesicular stomatitis viruses, and fish and plant rhabdoviruses.
Rhabon Valles
Rhabon Valles, a 245-km lava channel on Mars between Ascraeus Mons and Uranius Mons, centered near 21.2°N 268.7°E; IAU-named in 1988 for a classical river in Dacia, Romania.
Rhacophoridae
Rhacophoridae, the Old World tree frogs (Afro-Asian tree frogs, flying frogs), is a frog family of 494 species in two subfamilies, native to Subsaharan Africa and southern Asia, sister to Mantellidae.
Rhacophorus
Rhacophorus (flying frogs, parachuting frogs, 树蛙属) is a genus of 51 rhacophorid tree frog species from South and Southeast Asia, established in 1822, with contested internal taxonomy involving Leptomantis and Zhangixalus.
Rhacotis
Rhacotis, also Rhakotis, was a native Egyptian village on the Nile Delta coast, occupied from about 1000 BC, on the site where Alexander founded Alexandria in 332–331 BC.
Rhadamanthus (Ῥαδάμανθυς)
Rhadamanthus (Ῥαδάμανθυς), son of Zeus and Europa and brother of Minos, is the mythical Cretan lawgiver who after death became a judge of the dead in Elysium, judging Asian souls under Plato's Gorgias scheme.
Rhadamanthys Linea
Rhadamanthys Linea is a ~2000 km-long, low-albedo double ridge on Europa's northern trailing anti-Jovian hemisphere, IAU-named in 1985 after a son of Europa and Zeus; a transitional ridge-triple-band feature with dark marginal spots and possible plume deposits.
Rhadoo
Rhadoo is the stage name of Radu Bogdan Cilinca, a Romanian DJ and producer born in Galați in 1975, a defining figure of the Romanian minimal techno scene.
Rhaenyra Targaryen
Rhaenyra Targaryen, the Half-Year Queen, is George R.R. Martin's fictional first-born child of King Viserys I, named heir at eight, dragonrider of Syrax, wife of Laenor Velaryon and Daemon Targaryen, and queen claimant killed by Aegon II's dragon Sunfyre in the Dance of the Dragons.
Rhaenyra the Cruel
Rhaenyra the Cruel is a nickname for Rhaenyra Targaryen in George R.R. Martin's Fire & Blood, evoking Maegor the Cruel, and the title of House of the Dragon Season 2 Episode 2 (aired June 23, 2024), covering the aftermath of Aegon's heir's murder.
Rhaenyra Triumphant
"Rhaenyra Triumphant" is House of the Dragon season 3, episode 3 (HBO, aired July 5, 2026), written by Sara Hess, directed by Clare Kilner, following Queen Rhaenyra's troubled first days ruling King's Landing from the Red Keep.