72,234 articles
Partial thromboplastin time
Partial thromboplastin time (PTT, aPTT) is a coagulation blood test measuring seconds to fibrin clot via the intrinsic pathway; normal about 25-37 seconds; used for hemophilia workup, heparin monitoring, and lupus anticoagulant detection.
Partially involuting congenital hemangioma
Partially involuting congenital hemangioma (PICH) is a rare benign vascular tumor fully formed at birth that regresses like a RICH but stops partway, leaving a NICH-like residual lesion; ulceration is its hallmark complication.
Partington syndrome
Partington syndrome (PRTS, Partington-Mulley syndrome), an X-linked recessive ARX-gene (Xp22.13) disorder with intellectual disability, dysarthria, and progressive focal hand dystonia (Partington sign), first described in 1988.
Partitioning defective 3
PARD3 (PAR3, ASIP; Drosophila Bazooka) is a human chromosome 10 scaffold gene of the Par-3/Par-6/aPKC polarity complex, controlling asymmetric cell division, epithelial apicobasal polarity, and acting as context-dependent tumor suppressor or promoter.
Partner notification
Partner notification is a public health practice of informing the sexual or injecting partners of people diagnosed with HIV or other STIs so they can be tested and treated.
PARTNER trial
PARTNER (Placement of AoRTic TraNscathetER Valve) trial, NCT00530894, Edwards Lifesciences-sponsored randomized program comparing TAVR with medical therapy or surgery in severe aortic stenosis, spanning Cohorts A/B, PARTNER 2A, and PARTNER 3.
Partridge
Partridge: plump ground-dwelling gamebirds of Galliformes/Phasianidae, chiefly grey partridge (Perdix perdix) of farmland and Alectoris species such as chukar and red-legged partridge; distinguished by head pattern, flank barring, and red bills.
Partula (gastropod)
Partula is a genus of Pacific island tree snails (Partulidae) from the Society Islands to New Guinea; the rosy wolf snail's 1977 introduction drove 52 French Polynesian species extinct in the wild, and zoo breeding has since re-established Partula tohiveana.
Party and play
Party and play (PnP), also called chemsex, is drug use to facilitate or intensify sex, mainly among gay and bisexual men; typical drugs are methamphetamine, GHB/GBL, and mephedrone, with slamsex injecting raising HIV and hepatitis C risk.
Parulidae
Parulidae, the New World warblers or wood-warblers, is a family of small (9-15 cm) American insectivorous songbirds, unrelated to Old World warblers, with about 110-116 species, many long-distance migrants whose ancestral state was migratory.
Paruresis
Paruresis, also known as shy bladder syndrome or pee shyness, is the inability to urinate when others are present, usually manageable only when alone at home.
Parus
Parus is a genus of small passerine birds in the family Paridae, the tits and chickadees, erected by Linnaeus in 1758 and now restricted to the great tit group.
Parvalbumin
Parvalbumin (PV), also called PA, is a small acidic ~12 kDa EF-hand calcium-binding protein of fast-twitch muscle and GABAergic interneurons; first Ca2+-binding protein structurally resolved (1973), source of the EF-hand motif, and a major fish allergen.
Parvarchaeota
Parvarchaeota is a candidate archaeal lineage of very small microorganisms, one of the two ARMAN groups, discovered in acid mine drainage biofilms at Iron Mountain Mine in California.
Parvin
Parvin: family of α-, β-, and γ-parvin CH-domain adaptor proteins in the ILK-PINCH-parvin (IPP) complex at focal adhesions, linking integrins to actin; roles in adhesion, spreading, survival, cancer, NAFLD, and cardiac disease.
Parvoviridae
Parvoviridae: family of small non-enveloped ssDNA viruses (4–6 kb, 23–28 nm T=1 capsids) in subfamilies Parvovirinae, Densovirinae, Hamaparvovirinae; includes parvovirus B19 and adeno-associated viruses; rolling hairpin replication.
Parvovirosis
Parvovirosis, also called infection with parvoviruses, is disease caused by non-enveloped single-stranded DNA viruses of Parvoviridae affecting mammals, crustaceans, and arthropods; a non WOAH-listed wildlife disease, with canine parvovirus 2 causing hemorrhagic enteritis in dogs.
Parvovirus
Parvovirus (family Parvoviridae): small non-enveloped single-stranded DNA viruses, 4–6 kb genomes, 23–28 nm capsids, infecting vertebrates and invertebrates; includes human B19V and canine parvovirus.
Parvovirus B19
Parvovirus B19 (B19V, erythema infectiosum virus, fifth disease) is a human-only single-stranded DNA parvovirus causing slapped-cheek rash, aplastic crisis in hemolytic anemia, fetal hydrops, and chronic anemia in immunodeficiency.
PAS domain
PAS (Per-ARNT-Sim) domain, also called PAS fold, a ~100-residue sensor module in signal transduction proteins of all kingdoms of life; five-stranded antiparallel beta-sheet fold, under 20% sequence identity, binds heme, flavins, carboxylic acids, gases, and light via cofactors.
PAS trial
PAS trial (NCT06219564): a Turkish retrospective cohort study of 277 women with total placenta previa testing whether placental MRI volumes and cervical measurements predict peripartum hysterectomy and neonatal mortality in placenta accreta spectrum.
Pascal Chanez
Pascal Chanez is a French physician-scientist in respiratory medicine and allergology, professor at Marseille and head of its severe asthma clinic, co-author of the mepolizumab trials DREAM and MENSA.
Pascal Fries
Pascal Fries, born 1972, is a neuroscientist known for the communication-through-coherence hypothesis, built from recordings in visual cortex, leading research groups in Frankfurt and Tübingen.
Pascal Geldsetzer
Pascal Geldsetzer is a physician-scientist and Assistant Professor of Medicine at Stanford whose 2025 Nature study found shingles vaccination reduced dementia diagnoses by about 20%.
Pascal J. Goldschmidt‐Clermont
Pascal J. Goldschmidt-Clermont is a Belgian-trained cardiologist who led cardiology at Duke, directed Ohio State's Heart and Lung Research Institute, and was dean of the University of Miami's medical school from 2006 to 2016.
Pascal Meier
Pascal Meier is a Swiss-trained molecular cell biologist and professor at the Institute of Cancer Research, known for work on inhibitor of apoptosis proteins, cell death, and inflammation.
Pascal Ravassard
Pascal Ravassard is a French neuroscientist, first author of the 2013 Science study showing hippocampal place cells can measure distance, cited in the 2014 Nobel Prize background.
Pascal S. Kaeser
Pascal S. Kaeser, also published as Pascal Kaeser, is a Swiss-born physician-scientist and Professor of Neurobiology at Harvard Medical School who studies active zones and dopamine release.
Pascal Schneider
Pascal Schneider is a Swiss immunologist and senior lecturer at the University of Lausanne whose work on TNF-family proteins produced the 2018 prenatal correction of XLHED.
Pascale Allotey
Pascale Allotey is a global public health researcher who has directed the World Health Organization's Department of Sexual and Reproductive Health and Research since 2022.