| HEPA | high-efficiency particulate air [filter] |
|---|---|
| HPF | heparin-precipitable fraction; hepatic plasma flow; high-pass filter; high-power field [microscope];... |
| QMF | quadrature mirror filter |
| ULPA | ultra low penetration air filter |
| JVP | [POMD P 49 - 52] 1) Jugular Vein Pressure 2) Jugular Venous Pulse ... |
| closed reduction of fractures | Reduction by manipulation of bone, without incision in the skin. (05 Mar 2000) |
|---|---|
| closed skull fracture | Fracture with intact overlying scalp and/or mucous membranes. Synonym: simple skull fracture. (05 Mar 2000) |
| closed surgery | Surgery without incision into skin, e.g., reduction of a fracture or dislocation. (05 Mar 2000) |
| closed system | <biology, ecology> A chemical or biological system that exchanges no matter or energy with the ouside environment. (12 Mar 1998) |
| covalently closed circular DNA | <molecular biology> A circular molecule of double-stranded DNA which is supercoiled, or coiled up on itself due to internal tensions, because there are no breaks in the phosphate backbone (upon which the nucleotide bases are mounted) to relieve the tensions and allow it to form an open circle. (09 Oct 1997) |
| head injuries, closed | Organic or functional damage resulting from trauma to the head where continuity of the scalp and mucous membranes is maintained. When brain injury results from closed head injuries, the primary cause is mechanical stretching and shearing of nerve fibres. Also common are focal intracranial lesions including haematomas and contusions. (12 Dec 1998) |
| hemming filter | <apparatus> A filter placed between two tubes attached to each other, often used with centrifuges to selectively remove a substance of interest from a mixture in one tube and deposit the substance into the other tube. (09 Oct 1997) |
| high-pass filter | A device or material that allows high frequency signals to pass while attenuating other signals. (05 Mar 2000) |
| high quality filter paper | Used in paper chromatography. Synonym: high quality filter paper. Congo red paper, paper impregnated with Congo red; used as a pH indicator, changing from blue-violet at 3.0 to red at 5.0. Filter paper, an unsized paper used in pharmacy and chemistry for filtering solutions; many varieties are used for paper chromatography. (05 Mar 2000) |
| semi-closed anaesthesia | Inhalation anaesthesia using a circuit in which a portion of the exhaled air is exhausted from the circuit and a portion is rebreathed following absorption of carbon dioxide. (05 Mar 2000) |
| semi-closed circle | A circuit for administration of an inhalation anaesthetic in which partial rebreathing with carbon dioxide absorption is combined with loss from the circuit of a portion of respired gases through valves. (05 Mar 2000) |
| simon nitinol ivc filter | <radiology> Introduced 1990; Nitinol Medical Technologies, Woburn, MA. BARD, thermal memory alloy:titanium and nickel;, straightened form at cool temperatures (4-10C), reforms into predetermined filter shape at body temperatures efficacy, recurrent PE: 0 - 4.8%, IVC thrombosis: 7 - 11% (by clinical symptoms), access site thrombosis: 2 - 10% advantages, narrow introducer sheath (9 Fr), largest choice of access: brachial or left CFV approach without difficulty, only mild MRI artifacts disadvantages, IVC thrombosis: symptomatic occlusion rates higher than reported wtih Greenfield or bird's nest filters, caval penetration: 1 - 33%, caudal drop: exact filter location difficult to predict (12 Dec 1998) |
| spatial filter | <radiobiology> Device consisting of a lens pair and a pinhole aperture stop. Intensity fluctuations over the spatial extent of a laser beam are removed by passing the focused beam through the aperture stop. The pinhole must be placed in a vacuum to prevent air breakdown by the focused beam. These filters are used to counter the effects caused by self-focusing. (09 Oct 1997) |
| 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) |