All articles starting with P
28,818 articles
Primary angle closure glaucoma
Primary angle closure glaucoma (PACG), also called primary angle-closure glaucoma, is glaucoma with iris-trabecular meshwork angle obstruction plus optic nerve damage; pupillary block drives most cases, treated by laser iridotomy or lens extraction, affecting about 17 million people, mostly in Asia.
Primary angle-closure
Primary angle-closure disease (PACD), also called primary angle closure glaucoma spectrum, is iris obstruction of the trabecular outflow pathway, staged as PACS, PAC, and PACG, mainly caused by pupillary block and treated with laser peripheral iridotomy or lens extraction.
Primary antiphospholipid syndrome
Primary antiphospholipid syndrome (PAPS) is antiphospholipid syndrome occurring without another autoimmune disease, unlike secondary APS linked to SLE. It features thrombosis, pregnancy morbidity, and persistent antiphospholipid antibodies, classified by the 2023 ACR/EULAR criteria.
Primary arthroplasty
Primary arthroplasty is the replacement of a joint with prosthetic components performed as a first operation in that joint, done chiefly to relieve pain and restore function in osteoarthritis.
Primary basilar invagination
Primary basilar invagination (primary basilar impression, Bull-Nixon syndrome) is a rare congenital upward translocation of the upper cervical spine and clivus into the foramen magnum, autosomal dominant, often with Chiari I malformation, diagnosed by Chamberlain, McGregor, and McRae line criteria and treated surgically.
Primary biliary cholangitis
Primary biliary cholangitis (formerly primary biliary cirrhosis) is a chronic autoimmune liver disease destroying small bile ducts, affecting middle-aged women, diagnosed by ALP elevation and AMA, treated first with ursodeoxycholic acid.
Primary biliary cholangitis/primary sclerosing cholangitis and autoimmune hepatitis overlap syndrome
Primary biliary cholangitis/primary sclerosing cholangitis and autoimmune hepatitis overlap syndrome is an uncommon liver disorder in which autoimmune hepatitis occurs alongside primary biliary cholangitis or primary sclerosing cholangitis.
Primary bone lymphoma
Primary bone lymphoma is a rare lymphoma arising in bone with no disease elsewhere, usually diffuse large B-cell type, causing progressively worsening local bone pain.
Primary care
Primary care is essential first-contact, community-based health care, a subset of primary health care (PHC). Defined by Starfield's 4Cs, rooted in Alma-Ata 1978 and Astana 2018; linked to lower costs, fewer avoidable hospitalizations, and longer life expectancy.
Primary Care Nursing
Primary care nursing is the practice of nursing in first-contact settings like general practice and community health centers, centered on chronic disease management, health education, and health promotion.
Primary Care Physicians
Primary care physicians (PCPs, family physicians, general practitioners) are specialists in family medicine, internal medicine, pediatrics, or geriatrics providing first-contact, continuous, comprehensive, coordinated care and gatekeeping access to specialists.
Primary Cell Culture
Primary cell culture: freshly isolated, non-immortalized cells grown in vitro, retaining native tissue morphology and function; finite lifespan (Hayflick limit, ~6-10 passages), unlike immortalized cell lines.
Primary cesarean birth
A primary cesarean birth is a person's first cesarean delivery, counted separately from repeat cesareans because about 85% of women who have one have repeats for later births.
Primary chemotherapy
Primary chemotherapy, also called neoadjuvant, induction, or preoperative therapy, is systemic anticancer drug treatment given as the first treatment after diagnosis, before surgery or radiotherapy, so tumors can shrink and organ-sparing surgery becomes possible.
Primary choroidal lymphoma
Primary choroidal lymphoma (PCL), a rare low-grade extranodal marginal zone B-cell lymphoma of the choroid, formerly called reactive lymphoid hyperplasia; indolent, no CNS spread, good prognosis, treated with radiotherapy or rituximab.
Primary Chronicle
The Primary Chronicle, also called the Tale of Bygone Years or Nestor's Chronicle, is the earliest surviving East Slavic historical record, compiled in Kiev in the 1110s.
Primary ciliary dyskinesia
Primary ciliary dyskinesia (PCD, Kartagener syndrome when with situs inversus) is a rare autosomal recessive ciliopathy of motile cilia causing chronic sinopulmonary disease, laterality defects, and infertility, diagnosed by nNO, TEM, and genetics.
Primary color
Primary color: the defining colors of a color model, additive RGB for light, subtractive CMY for inks, traditional RYB; grounded in Young-Helmholtz trichromacy, Maxwell's work, and CIE standards like BT.2020 and D65.
Primary Colors (film)
Primary Colors is a 1998 American comedy-drama film directed by Mike Nichols and starring John Travolta, based on the anonymous novel about a Clinton-like presidential campaign.
Primary congenital glaucoma
Primary congenital glaucoma (PCG), also called trabeculodysgenesis or primary infantile glaucoma, is a rare bilateral childhood glaucoma from trabecular meshwork malformation; treated surgically (goniotomy, trabeculotomy), linked to CYP1B1, LTBP2, TEK genes.
Primary cutaneous actinomycosis
Primary cutaneous actinomycosis (ICD-11 1C10.3) is a rare primary skin infection by Actinomyces, chiefly A. israelii, after trauma; diagnosed by excluding deeper foci and sulfur granules, treated with penicillin for 6-12 months.
Primary cutaneous aggressive epidermotropic CD8+ T-cell lymphoma
Primary cutaneous aggressive epidermotropic CD8+ T-cell lymphoma, or Berti lymphoma, is a rare, highly aggressive skin T-cell lymphoma under 1% of CTCL, marked by rapidly ulcerating lesions, spread to lung and CNS, and about 18% five-year survival.
Primary cutaneous anaplastic large cell lymphoma
Primary cutaneous anaplastic large cell lymphoma (pcALCL, C-ALCL, ICD-O-4 97180/3) is an ALK-negative CD30+ cutaneous T-cell lymphoma, second most common after mycosis fungoides, presenting as solitary or multifocal skin nodules with 90% 10-year survival.
Primary cutaneous CD30-positive lymphoproliferative disorder
Primary cutaneous CD30-positive lymphoproliferative disorder (CD30+ LPD) is an indolent skin T-cell lymphoma spectrum spanning lymphomatoid papulosis and primary cutaneous anaplastic large-cell lymphoma, the second most common group of cutaneous T-cell lymphomas.
Primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma
Primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, now called primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder (PCSM-TCLPD), is a rare indolent skin T-cell proliferation presenting as a solitary CD4+, PD-1+ nodule on the face, neck, or upper trunk with excellent prognosis.
Primary cutaneous coccidioidomycosis
Primary cutaneous coccidioidomycosis (PCC) is a rare, localized Coccidioides skin infection from direct traumatic inoculation, without pulmonary disease. First described 1927; Wilson's 1953 diagnostic criteria; about 82 reported cases; azole treatment, excellent prognosis.
Primary cutaneous diffuse large B-cell lymphoma, leg type
PCDLBCL, leg type (PCDLBCL-LT) is a rare aggressive primary cutaneous B-cell lymphoma of elderly patients, usually on the lower legs, with MYD88/CD79B mutations, BCL2/MUM1 expression, ~50% 5-year survival, treated with R-CHOP plus radiation.
Primary cutaneous follicle center lymphoma
Primary cutaneous follicle center lymphoma (PCFCL), the most common primary cutaneous B-cell lymphoma, is an indolent skin lymphoma of head, neck, or trunk with BCL6-positive, BCL2-negative cells and over 95% five-year survival.
Primary cutaneous marginal zone B-cell lymphoma
Primary cutaneous marginal zone B-cell lymphoma (PCMZL) is an indolent B-cell lymphoma arising in the skin, causing recurring plaques or nodules but rarely spreading beyond it.
Primary cutaneous peripheral T-cell lymphoma not otherwise specified
Primary cutaneous peripheral T-cell lymphoma NOS (pcPTCL-NOS), also called primary cutaneous unspecified peripheral T-cell lymphoma, is a rare, aggressive skin T-cell lymphoma, about 2% of primary cutaneous lymphomas, treated with chemotherapy, with 5-year survival around 54% in the EORTC series.