| DEFT | direct epifluorescent filter technique |
|---|---|
| ESF | electron scatter function; electrosurgical filter; erythropoietic stimulating factor |
| filt | filter, filtration |
| HEPA | high-efficiency particulate air [filter] |
| HPF | heparin-precipitable fraction; hepatic plasma flow; high-pass filter; high-power field [microscope];... |
| neutral-density filter | <equipment> A light-absorbing filter whose absorption spectrum is moderately flat. Depending on the type, the absorption curve is flat primarily in the visible spectral range, or may extend to varying degrees beyond the visible range. For video microscopy, this is an important point since the absorbance may or may not extend into the near-infrared region where the sensitivity of many video image pickup devices is very high. (05 Aug 1998) |
|---|---|
| nitinol filter | A vena cava filter made with a metal that springs into shape when warmed to body heat by the blood after catheter insertion. (05 Mar 2000) |
| Nucleopore filter | Filter of defined pore size made by etching a polycarbonate filter that has been bombarded by neutrons, the extent of etching determining the pore size. Very thin, with neat circular holes going right through the membrane, not a complex meshwork like micropore filters. (18 Nov 1997) |
| DNA filter assay | <molecular biology> A lab technique used to identify the complementary base sequences of DNA. It involves immobilising the DNA on a filter and putting it in a solution that contains radioactively-labelled probe DNA or RNA molecules. (09 Oct 1997) |
| inferior vena cava filter | <radiology> Indications: contraindication to anticoagulation, failure of anticoagulation, complication of anticoagulation: haemorrhage or thrombocytopenia, large free-floating IVC/iliac vein thrombus expanded indications: cor pulmonale and DVT/PE, patients with high risk of complications to anticoagulation, metastatic disease, syncope in elderly, prophylactic placement in high-risk trauma patients, spinal cord injury, severe head injury, complex pelvic fractures, multiple long bone fractures, prophylactic placement before hip/knee replacement in patients with prior DVT prophylactic filters remain controversial see also: types of IVC filters (12 Dec 1998) |
| titanium greenfield ivc filter | <radiology> Advantages: low profile: 14.3 Fr introducer sheath, percutaneous placement, lack of ferromagnetic properties, low recurrent PE rate (3-5%), low IVC thrombosis rate (1-9%), successful placement (97%) disadvantages: maximum caval diameter = 28mm, tilting/leg assymetry, difficult placement from left femoral approach see also: indications (12 Dec 1998) |
| filter | 1. A porous substance through which a liquid or gas is passed in order to separate it from contained particulate matter or impurities. Synonym: filtrum. 2. To use or to subject to the action of a filter. 3. In diagnostic or therapeutic radiology, a plate made of one or more metals such as aluminum and copper that, placed in the x-or gamma-ray beam, permits passage of a greater proportion of higher energy radiation and attenuation of lower and less desirable energy radiation, raising the average energy or hardening the beam. 4. A device used in spectrophotometric analysis to isolate a segment of the spectrum. 5. A mathematical algorithm applied to image data for the purpose of enhancing image quality, usually by suppression of high spatial frequency noise. Origin: Mediev. L. Filtro, pp. -atus, to strain through felt, fr. Filtrum, felt (05 Mar 2000) |
| filter fabric | A fabric used to collect sediment from water flowing through a creek or through a gully. (09 Oct 1997) |
| filter sterilisation | A lab technique to sterilise a solution by passing it through a filter fine enough to catch bacteria-sized microorganisms. (09 Oct 1997) |
| low-pass filter | A device or material with the opposite effect from a high-pass filter; most tissues act as low-pass filters of ultrasound signals. (05 Mar 2000) |
| absorption chromatography | <investigation> Techniques for separating molecules based on differential absorption and elution. Term for separation methods involving flow of a fluid carrier over a nonmobile absorbing phase. (18 Nov 1997) |
| adsorption chromatography | Chromatography in which separation of substances is achieved by the difference in degree of adsorption of the compounds to a stationary phase. (05 Mar 2000) |
| affinity chromatography | <investigation> A technique of analytical chemistry used to separate and purify a biological molecule from a mixture, based on the attraction of the molecule of interest to a particular ligand which has been previously attached to a solid, inert substance. The mixture is passed through a column containing the ligand attached to the stationary substance, so that the molecule of interest stays within the column while the rest of the mixture continues through to the end. Then, a different chemical is flushed through the column to detach the molecule from the ligand and bring it out separately from the rest of the mixture. (09 Feb 1998) |
| gas chromatography | <technique> A chromatographic technique (a type of column chromatography) in which the stationary phase is solid while the mobile phase is gaseous samples. The gaseous samples are separated based on their different adsorption ability to the solid phase. (09 Oct 1997) |
| gas-liquid chromatography | <technique> A chemistry lab technique, a type of column chromatography, used to separate the components of a mixed substance. The substance is held stationary by an inert solid coated with an inert liquid which is not likely to evaporate (i.e. Is nonvolatile), while a gas (called an eluant) flows past it bringing out the components one at a time. (09 Oct 1997) |