All articles starting with S
44,216 articles
Secondary progressive multiple sclerosis
Secondary progressive multiple sclerosis (SPMS) is the MS stage following relapsing-remitting MS, marked by relapse-independent disability accrual (PIRA). About 50% of RRMS patients transition within 20 years; diagnosis is retrospective, and siponimod treats active SPMS.
Secondary psychotic syndrome
Secondary psychotic syndrome is a condition whose marked hallucinations or delusions arise directly from the pathophysiology of a medical illness or substance, coded 6E61 in the ICD-11.
Secondary pulmonary alveolar proteinosis
Secondary pulmonary alveolar proteinosis is a form of pulmonary alveolar proteinosis in which surfactant accumulates because an underlying disease, most often a myeloid blood cancer, impairs alveolar macrophages.
Secondary pulmonary hemosiderosis
Secondary pulmonary hemosiderosis, also called secondary pulmonary haemosiderosis, is lung iron deposition from repeated alveolar hemorrhage due to another disease such as mitral stenosis, autoimmune vasculitis, coagulation disorders, or Heiner syndrome, unlike idiopathic pulmonary hemosiderosis.
Secondary qualitative analysis
Secondary qualitative analysis is a social-science method of reusing qualitative data from earlier studies, such as interview transcripts and field notes, to answer new research questions.
Secondary Raynaud phenomenon
Secondary Raynaud phenomenon is episodic spasm of finger and toe blood vessels caused by an underlying disease, most often connective tissue disease such as systemic sclerosis.
Secondary resonance
A secondary resonance is a commensurability between libration within a mean motion resonance and the apsidal precession period, a source of chaos in the asteroid and Kuiper belts.
Secondary rhabdomyolysis
Secondary rhabdomyolysis (ICD-11 8C84) is muscle breakdown from external causes such as drugs, toxins, trauma, immobilization, or endocrine and electrolyte disorders, distinguished from primary inherited muscle disease, with CK thresholds and AKI risk guiding care.
Secondary school
Secondary school: schooling after primary education, divided by ISCED into lower secondary (level 2) and upper secondary (level 3), preparing students for work or tertiary education. Global 2024 completion: 78% lower, 61% upper secondary.
Secondary School Certificate
Secondary School Certificate (SSC): Grade 10 public examination qualification in Bangladesh, India, Pakistan, and Maldives; gateway to Higher Secondary Certificate study, administered by national and state education boards.
Secondary school physics teacher associations
Secondary school physics teacher associations are organizations of practicing physics teachers, led by the American Association of Physics Teachers (1930) and the Indian Association of Physics Teachers (1984).
Secondary sclerosing cholangitis
Secondary sclerosing cholangitis is a chronic bile duct disease marked by inflammation and stricturing that arises from an identifiable injury, unlike primary sclerosing cholangitis, which has no known cause.
Secondary Security Screening Selection
Secondary Security Screening Selection, or SSSS, is a TSA code printed on boarding passes, primarily on US flights, that selects passengers for enhanced checks like pat-downs, luggage searches, and explosive-trace swabs.
Secondary sex characteristic
Secondary sex characteristic: sexually dimorphic traits not directly involved in reproduction (breasts, beard, antlers, manes, plumage), triggered at puberty by GnRH/gonadarche and adrenarche, staged clinically by Tanner stages, and shaped by genetics, disorders, and hormone therapy.
Secondary Sjögren syndrome
Secondary Sjögren syndrome (sSS), now termed associated Sjögren disease, is Sjögren syndrome with another systemic autoimmune disease such as RA or SLE; the 2023 Rome consensus retired the term.
Secondary source
Secondary source: a work that analyzes, interprets, or synthesizes primary sources, created after the event by someone without firsthand experience. Includes scholarly books, articles, textbooks; same work can be primary depending on use.
Secondary spermatocyte
Secondary spermatocyte: haploid-chromosome male germ cell formed by meiosis I of a primary spermatocyte; DNA still 2N; completes meiosis II within hours to yield two spermatids.
Secondary succession
Secondary succession: reestablishment of a community after disturbance on a previously occupied site, leaving biological legacies such as seed banks; faster than primary succession, studied via Clements-Gleason theory and modern restoration research.
Secondary surveillance radar
Secondary surveillance radar (SSR) is an air traffic control system that interrogates aircraft transponders on 1030 MHz and receives replies on 1090 MHz, providing identity and altitude.
Secondary syringomyelia
Secondary syringomyelia (ORPHA:99857, ICD-10 G95.0) is a rare spinal cord disease: a syrinx forms secondary to blocked CSF flow, cord injury, dysraphism, or intramedullary tumors, causing dissociated sensory loss.
Secondary thrombocytopenic purpura
Secondary thrombocytopenic purpura (secondary immune thrombocytopenia, ICD-11 3B64.11): immune platelet loss from an identifiable cause such as SLE, HIV, hepatitis C, H. pylori, lymphoma, or drugs, affecting 10-20% of ITP cases.
Secondary thrombocytosis
Secondary thrombocytosis, also called reactive thrombocytosis (ICD-11 3B63.10), is a platelet count above 450 × 10⁹/L caused by another disorder such as infection, inflammation, iron deficiency, cancer, or splenectomy; it accounts for 80–90% of thrombocytosis and resolves when the cause is treated.
Secondary treatment
Secondary treatment is the stage of wastewater treatment that uses biological processes, usually aerobic microorganisms, to remove dissolved and finely suspended organic matter left after primary settling, chiefly by activated sludge and trickling filters.
Secondary tremor
Secondary tremor (ICD-11 8A04.3) is tremor caused by an identifiable underlying disorder, lesion, drug, or toxin, such as metabolic disturbances, cerebellar lesions, Holmes tremor, or drug-induced tremor, unlike primary tremor syndromes.
Secondary uterine inertia
Secondary uterine inertia, or arrested active phase of labor (ICD-10 O62.1, ICD-11 JB02.1), is the weakening or cessation of uterine contractions after initially adequate labor, treated with oxytocin augmentation or cesarean delivery.
Secondary vasculitis
Secondary vasculitis is blood vessel inflammation arising from another condition, such as lupus, rheumatoid arthritis, infections like hepatitis C, drugs, or cancer, rather than a primary vasculitic disorder.
Secondary yaws
Secondary yaws (ICD-11 1C1D.1) is the second stage of yaws, caused by hematogenous and lymphatic spread of Treponema pallidum subsp. pertenue weeks to two years after primary infection, with multiple papules, crab yaws, and dactylitis.
Secondcity
Secondcity is the alias of British house DJ and producer Rowan Harrington, whose track 'I Wanna Feel' reached number 1 on the UK Singles Chart in 2014.
Secondhand Lions
Secondhand Lions is a 2003 American comedy-drama written and directed by Tim McCanlies, starring Michael Caine, Robert Duvall, and Haley Joel Osment as a boy and his eccentric Texas great-uncles with a rumored fortune, released by New Line Cinema.
Seconds (1966 film)
Seconds (1966) is John Frankenheimer's black-and-white sci-fi drama, from David Ely's novel, in which banker Arthur Hamilton (John Randolph) is surgically remade as Rock Hudson's Tony Wilson; booed at Cannes, later reappraised.