All articles starting with P
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Premna
Premna L. (also Premna integrifolia, agnimantha) is a genus of about 130 species of trees, shrubs, and lianas in Lamiaceae, subfamily Premnoideae, native to the Old World tropics and used in traditional medicine.
Premonition (2007 film)
Premonition is a 2007 American supernatural thriller directed by Mennan Yapo, starring Sandra Bullock as a housewife who experiences the days around her husband's fatal car accident out of sequence.
Premonstratensians
Premonstratensians (Norbertines, White Canons, O. Praem.): Catholic order of canons regular founded by Norbert of Xanten at Prémontré near Laon in 1120-1121, following a stricter Rule of St Augustine with Cistercian-style organization and parish pastoral work.
Prempeh I
Prempeh I was the Asantehene, ruler of the Asante Empire in what is now Ghana, from 1888 to 1931; the British deposed and exiled him in 1896.
Prempeh II
Prempeh II, Nana Sir Osei Tutu Agyeman Prempeh II (1892–1970), was Asantehene, ruler of the Asante of Ghana from 1935, and led the restoration of the Asante Confederacy.
Přemyslid dynasty
The Přemyslid dynasty (Přemyslovci) was the ruling house of Bohemia from the ninth century until Wenceslaus III's 1306 murder; it also ruled Austria, Poland, and Hungary.
Prenatal care
Prenatal care (antenatal care) is health care during pregnancy, including screening, monitoring, and health promotion. Key facts: traditional 12-14 visit US model, WHO eight-contact guideline, ACOG 2025 tailored care, declining first-trimester initiation (75.5% in 2024).
Prenatal cocaine exposure
Prenatal cocaine exposure (PCE), the in utero exposure of a fetus to cocaine, rose with the 1980s crack epidemic; studied outcomes range from transient newborn neurological signs to adolescent emotion-regulation and behavioral difficulties, heavily confounded by polysubstance use and poverty.
Prenatal development
Prenatal development: human growth from fertilization to birth, split into an embryonic period (8 weeks, 23 Carnegie stages) and a fetal period; dated by first-trimester ultrasound, with milestones, term categories, and growth standards.
Prenatal radiation exposure
Prenatal radiation exposure is irradiation of the embryo or fetus from medical imaging, occupation, or emergencies. Effects depend on dose and gestational age; below 50-100 mGy no harm is reported, above 0.5 Gy effects can be severe.
Prenatal testing
Prenatal testing: screening (first-trimester combined, quad screen, cfDNA/NIPT) and diagnostic (CVS, amniocentesis) tests for fetal aneuploidy; cfDNA sensitivity ~99% for trisomy 21 but PPV depends on prevalence; procedure loss risk ~0.1-1%.
Prenetics
Prenetics is a Hong Kong consumer health and diagnostics company co-founded by Danny Yeung in 2014. It became a major covid-19 testing provider and listed on Nasdaq in 2022.
Prenex normal form
Prenex normal form (PNF), also called prenex form, is a standard form for first-order logic formulas in which all quantifiers are gathered at the front, before a quantifier-free matrix.
Prenuptial agreement
Prenuptial agreement (prenup, premarital or antenuptial agreement): a contract signed before marriage setting property, debt, and support terms for divorce or death; governed in the US by the UPAA and in England and Wales given weight but not automatic enforceability after Radmacher v Granatino (2010).
Prenylamine
Prenylamine (Segontin, Synadrin) was a phenylalkylamine antianginal drug marketed from 1960 by Hoechst and withdrawn in 1988 as the first QT-prolongation casualty; it helped found the calcium antagonist class.
Prenylated rab acceptor PRA1
Prenylated rab acceptor PRA1 (PRAF1, RABAC1, YIP3) is a small four-pass transmembrane protein and GDI displacement factor that binds prenylated Rab GTPases and VAMP2 to regulate vesicle trafficking; humans have three PRAF family members and plants an expanded family.
Prenyltransferase
Prenyltransferase (UbiA superfamily, COQ2, UBIAD1, MenA): intramembrane enzymes transferring isoprenyl groups from diphosphate donors to aromatic acceptors, making ubiquinone, menaquinone, chlorophyll, heme, and vitamin E; Mg2+-dependent, disease-linked, and antibiotic drug targets.
Preobrazhensky Prikaz
The Preobrazhensky Prikaz (Преображенский приказ) was a central institution of Muscovite Russia that administered Peter the Great's guard regiments and investigated state crimes, abolished in 1729.
Preobrazhensky Regiment
The Preobrazhensky Regiment (Преображенский полк) was the first guards regiment of Russia, raised by Peter I from his toy troops at Preobrazhenskoe near Moscow; it made and unmade monarchs until its disbandment in 1918.
Preoccupations
Preoccupations, formerly Viet Cong, is a Canadian post-punk band from Calgary formed in 2012 by ex-Women members Matt Flegel, Scott Munro, Daniel Christiansen, and Mike Wallace; albums include Viet Cong (2015) through Ill at Ease (2025).
Preon
A preon, also called a prequark or subquark, is a hypothetical subatomic particle proposed as a building block of quarks and leptons; no experiment has found quark substructure.
Preoperative Care
Preoperative care: medical assessment, optimization, and preparation of patients before surgery, spanning history and examination, risk-stratified testing (NICE NG45), cardiovascular evaluation (AHA/ACC), preanesthesia standards, and prehabilitation.
Preoperative Exercise
Preoperative exercise (exercise-based prehabilitation): structured training before elective surgery to raise functional capacity. Pooled data from 99 RCTs show fewer complications (OR 0.54) and shorter stay; evidence certainty varies by surgery type.
Preoperative Period
The preoperative period spans the time before surgery, from the decision to operate until the patient enters the operating room, covering assessment, testing, and fasting.
Preorder
A preorder, also called a quasiorder, is a binary relation on a set that is reflexive and transitive, and a partial order if also antisymmetric.
Preosteoblast
Preosteoblast (osteoprogenitor cell, CL:0007010): a skeletogenic intermediate cell between mesenchymal progenitor and osteoblast; expresses STRO1, ALP, PPR, type I collagen; regulated by RUNX2, SP7, Wnt; releases OPG to curb osteoclast resorption.
PrEP-PP study
PrEP-PP (PrEP in Pregnancy and Postpartum) is a demonstration cohort study (NCT03902418) of 1,195 pregnant women in Cape Town, South Africa, measuring PrEP initiation, continuation, adherence, and HIV incidence through 12 months postpartum.
Prepaid expense
A prepaid expense is a payment made in advance for goods or services, recorded first as an asset on the balance sheet and transferred to expense as the benefit is used up.
Prepar3D
Prepar3D is a visual simulation platform developed by Lockheed Martin, which bought Microsoft's ESP technology in 2009 and launched it in 2010 for training across aviation, maritime, and ground domains, from underwater to sub-orbital space.
Preparation for the Next Life (film)
Preparation for the Next Life is Bing Liu's 2025 romantic drama debut, adapted from Atticus Lish's PEN/Faulkner-winning novel, starring Sebiye Behtiyar and Fred Hechinger as an undocumented Uyghur immigrant and a PTSD-suffering US veteran in New York.