| ACCESS | Ambulatory Care Clinic Effectiveness Systems Study; automated cervical cell screening system |
|---|---|
| BSAM | basic sequential access method |
| DASD | direct access storage device |
| EACH | essential access community hospital |
| VAD | venous access device; ventricular assist device; vinblastine and dexamethasone; vitamin A deficiency... |
| random sample | A group selected randomly, solely by chance. (12 Dec 1998) |
|---|---|
| random sampling | A selection of elements by a formal randomizing device for purposes of inference about a population of inference from that population in such a way that the probability of each possible outcome may be precisely specified in advance; the inferences are necessarily stochastic. (05 Mar 2000) |
| random variable | A variable that may assume a set of values, each with fixed probabilities or probability densities (its distribution), in such a way that the total probability assigned to the distribution is unity; the random variable may be discrete, continuous, or mixed discrete-continuous. (05 Mar 2000) |
| random walk | <cell biology> A description of the path followed by a cell or particle when there is no bias in movement. The direction of movement at any instant is not influenced by the direction of travel in the preceding period. If changes of direction are very frequent, then the displacement will be small, unless the speed is very great and the object will appear to vibrate on the spot. Although the behaviour of moving cells in a uniform environment can be described as a random walk in the long term, this is not true in the short term because of persistence. (18 Nov 1997) |
| random waves | Wave's in the electroencephalogram which occur paroxysmally and asynchronously. (05 Mar 2000) |
| remote memory | Memory for events of long ago as opposed to recent events. (05 Mar 2000) |
| retrograde memory | Memory for that which occurred before an event such as a brain injury. (05 Mar 2000) |
| memory | Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory. (12 Dec 1998) |
| memory cell | <immunology> Cells of the immune system that do not respond immediately when it first encounters an antigen but facilitates the more rapid secondary response when the antigen is encountered on a subsequent occasion. The long lasting immune memory is humoral and resides in B-cells, although it appears that persistence of the antigen may be essential. T-cell memory is shorter. (14 Oct 1997) |
| memory disorder | Disturbances in registering an impression, in the retention of an acquired impression or in the recall of an impression. (12 Dec 1998) |
| memory loop | An electronic device for retrieving data that had been stored and/or displayed upon the oscilloscope at an earlier time; used for reviewing electrical events immediately preceding a specific disturbance. (05 Mar 2000) |
| memory span | The maximum number of items recalled after a single presentation (auditory or visual). (05 Mar 2000) |
| memory T-cell | A T-cell that bears receptors for a specific foreign antigen encountered during a prior infection or vaccination. After an infection or a vaccination, some of the T-cells that participated in the response remain as memory T-cells, which can rapidly mobilize and clone themselves should the same antigen be re-encountered during a second infection at a later time. (09 Oct 1997) |
| memory trace | See: engram. (05 Mar 2000) |
| mixed discrete-continuous random variable | <statistics> A random variable that may assume some values with probabilities and others with probability densities. For example, in a 35-year-old man with familial polyposis of the colon, the distribution of time until malignant disease occurs consists of a probability that he already has cancer (which would be assigned the waiting time 0), a probability density of developing it in the future and a probability that he will die of some other cause before he develops cancer. (05 Mar 2000) |