| single-foot | An irregular gait of a horse; called also single-footed pace. See Single, "Single-foot is an irregular pace, rather rare, distinguished by the posterior extremities moving in the order of a fast walk, and the anterior extremities in that of a slow trot." (Stillman (The Horse in Motion)) Source: Websters Dictionary (01 Mar 1998) |
|---|---|
| single-gene diseases | Hereditary disorders caused by a change (mutation) in a single gene. There are thousands of single-gene diseases including achondroplastic dwarfism, huntington disease, cystic fibrosis, sickle cell disease, duchenne muscular dystrophy, and haemophilia. Single-gene diseases typically describe classic simple mendelian patterns of inheritance (as autosomal dominant, autosomal recessive, and x-linked traits) by comparison with polygenic diseases. (12 Dec 1998) |
| single gene disorder | Hereditary disorder caused by a mutant allele of a single gene (for example, Duchenne muscular dystrophy, retinoblastoma, sickle cell disease). Compare: polygenic disorders. (09 Oct 1997) |
| single-hearted | Having an honest heart; free from duplicity. Sin"gle-heart"edly. Source: Websters Dictionary (01 Mar 1998) |
| single immunodiffusion | See: gel diffusion precipitin tests in one dimension, gel diffusion precipitin tests in two dimensions. (05 Mar 2000) |
| single lucent skull lesion | <radiology> Mnemonic: HELP ME, haemangioma, epidermoid / dermoid, leptomeningeal cyst, lambdoid suture defect, Paget's (osteoporosis circumscripta), post-surgical, metastasis (solitary), eosinophilic granuloma, encephalocele (12 Dec 1998) |
| single-minded | Having a single purpose; hence, artless; guileless; single-hearted. Source: Websters Dictionary (01 Mar 1998) |
| single parent | An unmarried natural, adoptive, or substitute parent of a dependent child, whether living with or visiting the child. To be used also for single-parent families. The concept includes the never-married, as well as the divorced and widowed. (12 Dec 1998) |
| single-payer system | An approach to health care financing with only one source of money for paying health care providers. The scope may be national (the canadian system), state-wide, or community-based. The payer may be a governmental unit or other entity such as an insurance company. The proposed advantages include administrative simplicity for patients and providers, and resulting significant savings in overhead costs. (12 Dec 1998) |
| single person | The unmarried man or woman. (12 Dec 1998) |
| single photon emission computed tomography | <radiology> Tomographic imaging of metabolic and physiological functions in tissues, the image being formed by computer synthesis of photons of a single energy emitted by radionuclides administered in suitable form to the patient. The method uses radionuclides which emit a single photon of a given energy. The camera is then rotated 180 or 360 degrees around the patient to capture images at multiple positions along the arc. The computer then reconstructs the transaxial, sagittal, and coronal images from the 3-dimensional distribution of radionuclides in the target area scanned. The advantages of SPECT are that it can be used to observe biochemical and physiological processes as well as the size and volume of the organ. The disadvantage is that, unlike positron emission tomography where the positron-electron annihilation results in the emission of 2 photons at 180 degrees from each other, SPECT requires physical collimation to line up the photons, which results in the loss of available photons and hence degrades the image. Acronym: SPECT (20 Jun 2000) |
| single-strand break | A break in double-stranded DNA in which only one of the two strands has been cleaved; both strands have not separated from each other. (05 Mar 2000) |
| single stranded binding protein | <protein> SSB's are proteins responsiblefor holding the replication fork of DNAopen while polymerases readthe templates. (09 Oct 1997) |
| single stranded conformational polymorphism | Technique for detecting point mutations in genes by amplifying a region of genomic DNA (using asymmetric PCR) and running the resulting product on a high quality gel. Single base substitutions can alter the secondary structure of the fragment in the gel, producing a visible shift in its mobility. (18 Nov 1997) |
| single stranded DNA | <molecular biology> DNA that consists of only one chain of nucleotides rather than the two base pairing strands found in DNA in the double helix form. Parvoviridae have a single stranded DNA genome. Single stranded DNA can be produced experimentally by rapidly cooling heat denatured DNA. Heating causes the strands to separate and rapid cooling prevents renaturation. (18 Nov 1997) |