72,234 articles
Checklist of Australian spider families and genera
The Checklist of Australian Spiders, maintained by Volker Framenau, catalogs Australia's spider fauna at roughly 87 families, 677 genera, and 3,935 described species, led by jumping spiders.
CheckMate 9ER trial
CheckMate 9ER (NCT03141177) is a phase 3 open-label trial of first-line nivolumab plus cabozantinib versus sunitinib in advanced renal cell carcinoma, showing superior PFS, overall survival, and response rates.
Checkpoint inhibitor immunotherapy
Checkpoint inhibitor immunotherapy is a cancer treatment using monoclonal antibodies that block immune checkpoints like CTLA-4, PD-1, and PD-L1, releasing T cells to attack tumors; it earned the 2018 Nobel Prize.
Checkpoint protein Rad17/Rad24, fungi/metazoa
Rad17/Rad24 checkpoint protein: conserved AAA+ clamp-loader large subunit (Rad17 in S. pombe and metazoa, Rad24 in S. cerevisiae) that loads the 9-1-1 checkpoint clamp at 5'-recessed DNA junctions to activate ATR-dependent DNA damage checkpoints.
Cheddar Man
Cheddar Man: Mesolithic male skeleton found 1903 in Gough's Cave, Cheddar Gorge, Somerset; Britain's oldest near-complete human skeleton, about 10,000 years old; 2018 DNA showed blue eyes and dark skin, haplogroup U5b1.
Chédiak-Higashi syndrome
Chédiak-Higashi syndrome (Chédiak-Higashi-Steinbrink syndrome) is a rare autosomal recessive LYST-gene disorder with partial albinism, immunodeficiency, bleeding, neurodegeneration, and HLH risk; giant leukocyte granules are diagnostic.
Cheese mite
The cheese mite is a storage mite, chiefly Tyrolichus casei and Acarus siro, that infests cheese and is deliberately used to ripen Milbenkäse and Mimolette.
Cheesecloth
Cheesecloth, also called butter muslin at its finest grade, is a loosely woven cotton gauze first recorded in the 1650s for pressing cheese curds; sold in grades 10 to 90 by thread count for straining, draining, and wrapping.
Cheesemaking
Cheesemaking: coagulating milk with rennet or acid, draining whey, and ripening curd with starter cultures and salt to make about 1,500 cheese varieties; over 20 million tons produced yearly worldwide.
Cheetah
Cheetah (Acinonyx jubatus), world's fastest land mammal at 96-112 km/h in short sprints; Vulnerable IUCN species with under 7,000 wild individuals, CITES Appendix I since 1975, surviving mainly in African savannas with a critically endangered Asiatic population in Iran.
Cheilanthes
Cheilanthes, the lip ferns, is a genus of xerophytic Pteridaceae ferns with marginal sori covered by lip-like leaf margins. Once over 150 species, it proved polyphyletic; Myriopteris was resurrected in 2013 and recent classifications synonymize Cheilanthes.
Cheilanthoideae
Cheilanthoideae, the cheilanthoid or lip ferns, a xeric-adapted subfamily of Pteridaceae with about 500 species in seven lineages; hemionitids reclassified into 22 monophyletic genera in 2025.
Cheilectomy
Cheilectomy is a joint-sparing operation for mild-to-moderate hallux rigidus, removing dorsal osteophytes and up to 30% of the metatarsal head to relieve pain and restore motion.
Cheilitis
Cheilitis, also called chilosis or chapped lips, is inflammation of the lips arising mainly in the vermilion, with causes including irritants, allergens, and sun exposure.
Cheilitis glandularis
Cheilitis glandularis, or glandular cheilitis, is a rare inflammatory disorder of the lower lip's minor salivary glands causing lip swelling and thick mucus secretion; under 100 cases reported, cause unknown, with rare squamous cell carcinoma risk.
Cheiloceras
Cheiloceras, extinct Late Devonian goniatite ammonoid genus (Frech 1897, type species Goniatites subpartitus), namesake of the lowermost Famennian Cheiloceras Stufe, involute shell, simple sutures, sexually dimorphic.
Cheiloplasty
Cheiloplasty is a surgical procedure that repairs lip defects by reconstructing lip structure and restoring function and appearance, used most often for primary cleft lip repair in infants.
Cheiracanthium
Cheiracanthium, long-legged sac spiders, is a genus of Cheiracanthiidae spiders erected by C. L. Koch in 1839, type species C. punctorium, with about 232 accepted species worldwide except the Polar Regions.
Cheiracanthium inclusum
Cheiracanthium inclusum, the agrarian or black-footed yellow sac spider (Hentz, 1847), is a pale yellow nocturnal hunting spider native to the Americas, outdoor-dwelling unlike the indoor C. mildei, with cytotoxic venom and up to five 40-egg sacs per season.
Cheirogaleus
Cheirogaleus, the dwarf lemurs, is a genus of small nocturnal Malagasy primates in Cheirogaleidae, including C. medius, C. major, and C. crossleyi, known for tail fat storage and primate hibernation.
Cheirolepidiaceae
Cheirolepidiaceae, an extinct worldwide conifer family of the Triassic to latest Cretaceous or early Paleocene, diagnosed by Classopollis pollen, with Frenelopsis and Pseudofrenelopsis foliage and sister-to-crown-group conifer affinities.
Cheirolepis
Cheirolepis is an extinct Devonian ray-finned fish genus (Agassiz 1835; type species C. trailli) from Scotland, Canada, and Nevada, the sister taxon of all other actinopterygians, distinct from the plant Euphorbia cheirolepis and the fossil pollen genus.
CHEK1
CHEK1 (checkpoint kinase 1, CHK1), human gene at 11q24.2 encoding a serine/threonine kinase activated by ATR that enforces DNA damage and replication checkpoints by phosphorylating CDC25 phosphatases.
CHEK2
CHEK2, checkpoint kinase 2, is a human gene on chromosome 22 that encodes a kinase in the DNA damage response, and its inherited variants raise breast cancer risk.
Chelatase
Chelatases are enzymes inserting divalent metal ions into tetrapyrroles to form heme, chlorophyll, cobalamin, and F430. Three classes: ATP-dependent AAA+ (Mg-chelatase ChlHID), ATP-independent (ferrochelatase), multifunctional.
Chelation therapy
Chelation therapy uses chelating agents such as EDTA, dimercaprol, DMSA, and DMPS to bind and excrete heavy metals; established for lead and metal poisoning, unproven and unapproved for heart disease after TACT and TACT2 trials.
Chelicerae
Chelicerae are the first pair of mouthpart appendages in chelicerate arthropods (spiders, scorpions, mites, horseshoe crabs). In spiders they bear venom-injecting fangs; a 2025 study proposes hydraulic pressure drives their movement.
Chelicerata
Chelicerata: arthropod subphylum with chelicerae and no antennae, including Arachnida (spiders, scorpions, mites), Xiphosura (horseshoe crabs), and Pycnogonida (sea spiders); over 100,000 species, Cambrian origin, contested arachnid monophyly.
Chelidae
Chelidae, side-necked freshwater turtles of South America and Australia–New Guinea; about 58 living species, Early Cretaceous origin, long neck evolved independently in each geographic clade.
Chelidonium
Chelidonium (greater celandine, bai qu cai 白屈菜) is a Papaveraceae genus of five species, best known for Chelidonium majus, an alkaloid-rich medicinal herb whose oral use carries documented idiosyncratic hepatotoxicity risk.