All articles starting with P
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Ptesanwi Mons
Ptesanwi Mons is a 200 km diameter volcanic mons on Venus at 2.80°N, 45.40°E in the Mead quadrangle (V-21), named in 2003 by the IAU for the Lakota Sioux White Buffalo Woman, with mapped lobate lava flows.
PTF boat
A PTF boat, or Patrol Torpedo Fast, was a fast, shallow-draft US Navy combatant craft of the Vietnam War era, most closely identified with the Norwegian-designed Nasty class.
PtGa
PtGa, or platinum gallide, is a chiral topological semimetal made of platinum and gallium, notable for the strongest spin-orbit coupling of any chiral crystal and for hosting multifold fermions.
PTGER4
PTGER4 (EP4, EP4R) is a human gene on chromosome 5p13.1 encoding the prostaglandin E2 receptor EP4, a Gs-coupled GPCR; linked to Crohn's disease, rheumatoid arthritis progression, and EP4-antagonist drug development.
PTGES
PTGES (mPGES-1, MPGES1, PIG12) is a human chromosome 9 gene encoding a glutathione-dependent prostaglandin E synthase that converts PGH2 to PGE2 downstream of COX-2; IL1B- and TP53-inducible, MAPEG-family, an anti-inflammatory drug target.
PTGS1
PTGS1 (COX1, prostaglandin-endoperoxide synthase 1) is the human chromosome 9q33.2 gene encoding cyclooxygenase-1, the constitutive homodimeric enzyme converting arachidonate to PGH2 and the aspirin target in platelets.
PTGS2
PTGS2 (COX-2, prostaglandin-endoperoxide synthase 2), human gene ID 5743 on chromosome 1q25.2-q25.3, encodes the inducible cyclooxygenase converting arachidonic acid to PGG2 and PGH2; target of coxib NSAIDs.
PTH1R
PTH1R (PTHR1, parathyroid hormone 1 receptor), a class B GPCR at 3p21.31 for PTH and PTHrP regulating calcium homeostasis and skeletal development; activating mutations cause Jansen metaphyseal chondrodysplasia, inactivating ones Blomstrand chondrodysplasia and tooth eruption failure.
Pthiriasis
Pthiriasis (pediculosis pubis, pubic lice, "crabs") is ICD-11 1G03, infestation by the crab louse Pthirus pubis, spread mainly sexually; treated with permethrin 1% or pyrethrins, with STI screening advised.
Ptiliidae
Ptiliidae, featherwing beetles (synonyms Trichopterygidae, Limulodidae), a staphylinoid beetle family of the smallest beetles and non-parasitic insects, under 1 mm, mycophagous, with feather-like bristled hind wings.
Ptilinopus
Ptilinopus (fruit-doves, fruit-pigeons), a Swainson 1825 genus of colorful frugivorous pigeons in Columbidae, spanning Southeast Asia to Polynesia; about 50-55 species, partly split into Megaloprepia and Ramphiculus in 2025.
Ptinidae
Ptinidae (spider beetles; synonym Anobiidae) is a beetle family in Bostrichoidea with 12 subfamilies and nearly 4,200 species; larvae are wood-boring pests of furniture, timber, and stored products.
PTK2
PTK2 (FAK, focal adhesion kinase) is a human gene at 8q24.3 encoding a 1052-amino-acid non-receptor tyrosine kinase active at focal adhesions, central to cell migration and survival, overexpressed in many cancers, and targeted by defactinib and other investigational inhibitors.
PTK2B
PTK2B (Pyk2, CAK-beta, RAFTK) is a human chromosome 8p21.1 gene encoding a calcium-regulated non-receptor tyrosine kinase of the FAK family, involved in integrin signaling, osteoclast bone resorption, and Alzheimer's disease risk.
PTN_POPS study
PTN_POPS (NCT01431326, NICHD-2011-POP01) is the Pediatric Trials Network's observational pharmacokinetic study of understudied drugs given per standard of care to children under 21, enrolling 3,520 participants from 2011 to 2019 across dozens of drugs and sites.
Ptolemaeus (lunar crater)
Ptolemaeus is a 153.67 km ancient lava-flooded lunar impact crater at 9.16S, 1.84W, named for Claudius Ptolemy; northernmost of the Ptolemaeus-Alphonsus-Arzachel crater chain, oldest of the trio, with no central peak.
Ptolemaeus (Martian crater)
Ptolemaeus is a 165-km-wide impact crater at 45.88° S, 202.40° E in Mars' southern hemisphere, IAU-named in 1973 for the Greco-Egyptian astronomer Claudius Ptolemy; distinct from the lunar crater of the same name.
Ptolemaic army
The Ptolemaic army was the multiethnic army of Ptolemaic Egypt (323–30 BC), made up of Greco-Macedonian settlers, mercenaries, and native Egyptians, fielding about 70,000 men at Raphia in 217 BC.
Ptolemaic Baris
The Ptolemaic Baris, the Birah of the Mishnah and Nehemiah, was a fortress at Jerusalem north of the Temple, rebuilt by Herod as the Antonia.
Ptolemaic campaign into Nubia
The Ptolemaic campaign into Nubia, commanded by Ptolemy II Philadelphus, was a 275 BC expedition against Kush that temporarily extended Ptolemaic control south to the Second Cataract.
Ptolemaic Canon
The Ptolemaic Canon, also called the Canon of Kings, is a list of rulers and reign lengths compiled by Ptolemy, running from 747 BC to his own time.
Ptolemaic coinage
Ptolemaic coinage is the coinage of Ptolemaic Egypt, a closed currency system of gold, silver, and bronze struck from Ptolemy I to Cleopatra VII, with its own weight standard.
Ptolemaic cult of Alexander the Great
The Ptolemaic cult of Alexander the Great was a state cult founded by Ptolemy I in Alexandria around 290 BC, serving as the frame of the dynastic cult.
Ptolemaic dynasty
Ptolemaic dynasty, also called the Lagid dynasty: Macedonian Greek royal house ruling Egypt 305–30 BC, founded by Ptolemy I Soter, general of Alexander the Great; ended with Cleopatra VII's defeat and Roman takeover.
Ptolemaic Kingdom
The Ptolemaic Kingdom, founded by Ptolemy I Soter after Alexander's death (323 BC; king from 305/4 BC), was the longest-lasting Hellenistic successor state, ruling Egypt from Alexandria until Cleopatra VII's defeat at Actium in 31 BC and Roman annexation in 30 BC.
Ptolemaic navy
The Ptolemaic navy was the fleet of Ptolemaic Egypt, based at Alexandria. Under Ptolemy II it was the leading naval power of the third-century-BC Mediterranean.
Ptolemaic ruler cult
The Ptolemaic ruler cult, state cult of living and deceased Ptolemaic rulers, was founded under Ptolemy II Philadelphos in the 270s BC and had Greek and Egyptian temple forms.
Ptolemaios (son of Glaucias)
Ptolemaios son of Glaucias was a Macedonian katochos, or temple recluse, in the Serapeum of Memphis in Ptolemaic Egypt, detained there 15 years by his own 158 BC petition.
Ptolemaios/Traianos Potamos
Ptolemaios/Traianos Potamos, also Diôrus, was the ancient Nile-to-Red-Sea canal through Egypt's Wadi Tumilat, begun under Necho II and Darius I, restored by Ptolemy II and reworked by Trajan (98–117 CE), and used in Roman Indo-Mediterranean trade.
Ptolemais Hermiou
Ptolemais Hermiou, also called Ptolemais in Upper Egypt, was a Greek city on the Nile founded by Ptolemy I, capital of Upper Egypt under the Ptolemies.