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Spartina alterniflora
Spartina alterniflora, now Sporobolus alterniflorus, smooth or saltmarsh cordgrass, a C4 salt marsh grass native from eastern Canada to Argentina, dominant in low marsh, invasive in China and San Francisco Bay, parent of Spartina xtownsendii.
Spartina patens
Spartina patens, saltmeadow cordgrass or marshhay cordgrass (syn. Sporobolus pumilus), a rhizomatous high-marsh grass from Newfoundland to Texas, tolerant of 0-35 ppt salinity, used for salt hay and restoration, invasive on the Pacific coast.
Spartium junceum
Spartium junceum, known as Spanish broom (Spanish: retama de olor), is a shrub in the legume family, native to the Mediterranean and grown for fragrant yellow flowers but invasive elsewhere.
SPARX Group
SPARX Group (スパークス・グループ) is an independent asset management group headquartered in Tokyo, founded by Shuhei Abe in 1989, which manages Japanese and Asian equities, real assets, and private equity.
Spaser
The spaser, short for surface plasmon amplification by stimulated emission of radiation, is a nanoscale device producing coherent light below light's wavelength, the nanoplasmonic counterpart of the laser.
Spasm
Spasm: sudden involuntary contraction of one or more muscles (also called muscle cramp, charley horse). Distinct from dystonia and spasticity; quinine reduces cramps but is restricted for toxicity, magnesium shows no benefit in older adults.
Spasm of accommodation
Spasm of accommodation (pseudomyopia, ciliary spasm, ICD-11 9D01.2) is excessive ciliary contraction causing sudden apparent myopia that resolves with cycloplegia; causes include close work, stress, and head trauma.
Spasm of conjugate gaze
Spasm of conjugate gaze (conjugate gaze spasm, CGS): sudden involuntary movement of both eyes in the same direction from extraocular muscle spasm; ICD-10-CM H51.0, ICD-11 9C83.1; includes oculogyric crisis.
Spasm of the near reflex
Spasm of the near reflex (SNR), also called convergence or accommodative spasm, is an intermittent triad of convergent strabismus, pseudomyopia, and miosis, first named by Cogan in 1955; mostly functional, treated with cycloplegics and fogging.
Spasmodic dysphonia
Spasmodic dysphonia, or laryngeal dystonia, is a rare focal dystonia causing involuntary laryngeal muscle spasms, voice breaks, and strained or breathy speech, treated mainly with botulinum toxin injections.
Spasmodic torticollis
Spasmodic torticollis (cervical dystonia): the most common adult-onset focal dystonia, causing involuntary head turning, tilting, and tremor. Treated mainly with botulinum toxin; features geste antagoniste sensory tricks and prominent pain.
Spasmus nutans
Spasmus nutans, a rare benign infantile eye-movement disorder with the triad of asymmetric pendular nystagmus, head nodding, and torticollis; onset 4-12 months, spontaneous remission, but mimicked by optic pathway glioma.
Spastic bilateral cerebral palsy
Spastic bilateral cerebral palsy (ICD-11 8D20.1; SCPE bilateral spastic CP, formerly diplegia/quadriplegia) is spasticity affecting both body sides, about 60% of CP cases, with variable walking ability, gait scissoring, and rehabilitation evidence.
Spastic cerebral palsy
Spastic cerebral palsy, the most common CP type at about 80% of cases, features increased muscle tone with diplegic, hemiplegic, and quadriplegic subtypes; treated with botulinum toxin A, therapy, and selective dorsal rhizotomy.
Spastic diplegia
Spastic diplegia, also called Little's disease or bilateral spastic cerebral palsy, is the most common cerebral palsy subtype, with leg spasticity exceeding arm involvement; treated with SDR, physiotherapy, and rehabilitation.
Spastic hemiplegia
Spastic hemiplegia (ICD-11 MB53.2, ICD-10 G81.1) is one-sided paralysis with involuntary contractions and increased muscle tone, seen as unilateral spastic cerebral palsy in children and post-stroke hemiparesis in adults, affecting the arm more than the leg.
Spastic paraplegia type 2
Spastic paraplegia type 2 (SPG2, X-linked spastic paraplegia 2) is a rare X-linked recessive leukodystrophy caused by PLP1 mutations, allelic with Pelizaeus-Merzbacher disease, causing childhood-onset spastic gait, autonomic dysfunction, and hypomyelination.
Spastic paraplegia type 7
Spastic paraplegia type 7 (SPG7) is a rare autosomal recessive hereditary spastic paraplegia caused by SPG7 gene variants encoding mitochondrial paraplegin, with adult-onset leg spasticity, ataxia, and optic atrophy.
Spastic paraplegia-intellectual disability-nystagmus-obesity syndrome
SINO syndrome (spastic paraplegia-intellectual disability-nystagmus-obesity syndrome, ORPHA:521390, OMIM 617296) is a rare autosomal dominant KIDINS220-related neurodevelopmental disorder with congenital spastic paraplegia, intellectual disability, nystagmus, and obesity.
Spastic paraplegia-optic atrophy-neuropathy syndrome
SPOAN syndrome (spastic paraplegia-optic atrophy-neuropathy syndrome, OMIM 609541) is an autosomal recessive hereditary spastic paraplegia caused by a 216-bp non-coding deletion upregulating KLC2 on 11q13, concentrated in northeastern Brazil, with congenital optic atrophy, infancy-onset spastic paraplegia, and axonal neuropathy.
Spastic peristalsis
Spastic peristalsis (ICD-11 DA21.22), also called distal or diffuse esophageal spasm, is a rare esophageal motility disorder with spastic non-peristaltic contractions causing chest pain and dysphagia, diagnosed by high-resolution manometry.
Spastic tetraplegia
Spastic tetraplegia (痙性四肢麻痺) is four-limb paralysis with velocity-dependent muscle tone from stretch-reflex hyperexcitability; ICD-11 code MB50.1, ICD-10-AM G82.4, seen after cervical spinal cord injury, cerebral palsy, and stroke.
Spastic unilateral cerebral palsy
Spastic unilateral cerebral palsy (USCP, spastic hemiplegia, ICD-11 8D20.0) is one-sided spastic CP, 40–60% of spastic cases, with bilateral weakness, sensory impairment, and CIMT or bimanual therapy.
Spasticity
Spasticity (muscle spasticity) is a velocity-dependent increase in stretch reflexes and muscle tone after upper motor neuron lesions, seen in stroke, spinal cord injury, multiple sclerosis, and cerebral palsy, treated with therapy, baclofen, botulinum toxin, and intrathecal baclofen.
Spastin
SPAST (SPG4, spastin) is a human gene on chromosome 2p22.3 encoding the AAA-family microtubule-severing enzyme spastin; heterozygous pathogenic variants cause spastic paraplegia type 4, the most common autosomal dominant hereditary spastic paraplegia.
Spatangoida
Spatangoida (heart urchins), order of irregular sea urchins named by Claus in 1876; deposit-feeding burrowers first appearing in the Berriasian, radiating in the Cretaceous, defined by a compact apical system, and surviving today in all oceans.
Spatax study
SPATAX (Spastic Paraplegia and Ataxia network) is a European clinical-genetic cohort study of cerebellar ataxias and hereditary spastic paraplegias, database created 2000, hosted at the Paris Brain Institute, coordinated by Alexandra Durr, closed 17 May 2022.
Spatha
Spatha: the double-edged, parallel-sided long sword of the Roman army and Germanic successor peoples; adopted from Celtic cavalry use, it replaced the gladius as standard infantry sword by the 3rd century.
Spathi / Lasithiotika
Spathi (Σπαθί), also recorded as Lasithiotika, is a 2,148-meter peak in the Dikti range of eastern Crete, Greece, generally regarded as the range's highest summit.
Spathiphyllum
Spathiphyllum, peace lily, is a genus of about 40-60 evergreen Araceae herbs from tropical America and Malesia, grown as houseplants for white spathes; toxic from calcium oxalates.