| A [band] | the dark-staining zone of a striated muscle |
|---|---|
| DK | dark; decay; diabetic ketoacidosis; diet kitchen; diseased kidney; dog kidney [cells] |
| B1 | induced field in magnetic resonance imaging; radiofrequency magnetic field in nuclear magnetic reson... |
| EF | ectopic focus; edema factor; ejection fraction; elastic fibril; electric field; elongation factor; e... |
| FA | false aneurysm; Families Anonymous; Fanconi anemia; far advanced; fatty acid; febrile antigen; femor... |
| stop-speculum | A dilating speculum, as a speculum of the eyelids, which is provided with a catch to prevent its being opened too wide. (05 Mar 2000) |
|---|---|
| quick-stop mutant | A bacterial mutant that ceases replication immediately when the temperature reaches a certain level. Compare: temperature-sensitive mutant. (05 Mar 2000) |
| Krueger instrument stop | A mechanical device limiting the insertion of a root canal instrument into a canal. (05 Mar 2000) |
| dark adaptation | The adjustment of the eye occurring under reduced illumination in which the sensitivity to light is greatly increased or the light threshold is greatly reduced. Dark adaptation is slower than light adaptation. During dark adaptation rhodopsin is built up in the retinal rods. (12 Dec 1998) |
| dark-adapted eye | An eye that has been in darkness or semidarkness and has undergone regeneration of rhodopsin (visual purple), which renders it more sensitive to reduced illumination. Synonym: scotopic eye. (05 Mar 2000) |
| dark cell | Cell's in eccrine sweat glands having many ribosomes and mucoid secretory granules. (05 Mar 2000) |
| dark current | <physiology> Current caused by constant influx of sodium ions into the rod outer segment of retinal photoreceptors and that is blocked by light (leading to hyperpolarization). The plasma membrane sodium channel is controlled through a cascade of amplification reactions initiated by photon capture by rhodopsin in the disc membrane. (18 Nov 1997) |
| dark-ground illumination | dark-field illumination |
| dark reaction | <biochemistry, plant biology> The reactions in photosynthesis that occur after NADPH and ATP production and that take place in the stroma of the chloroplast. By means of the reaction, carbon dioxide is incorporated into carbohydrate. (18 Nov 1997) |
| dark t2 lesion | <radiology> (short T2), acute haemorrhage (deoxyHb), haemosiderin, physiologic iron (basal ganglia, etc.), mucinous lesions (?) most abnormalities have long T1 and T2 (dark/bright). Compare: bright T1 lesion. (07 Mar 2000) |
| auditory field | The space included within the limits of hearing of a definite sound, as of a tuning fork. (05 Mar 2000) |
| bright field illumination | <microscopy> The method of lighting the specimen with a solid cone of rays. Transmitted bright field illumination is performed by a substage condenser. Reflected bright field illumination is performed by a vertical illuminator. Compare: dark field illumination (05 Aug 1998) |
| bright field imaging | <microscopy> An imaging mode in a transmission electron microscopy that uses only unscattered Electrons to form the image. Contrast in such an image is due entirely to mass-thickness variations in amorphous samples, and may include diffraction contrast in crystalline samples. (05 Aug 1998) |
| bright field microscopy | <technique> Optical microscopy, in which absorption to a great extent and diffraction to a minor extent give rise to the image, as opposed to phase contrast or interference methods of microscopy. (18 Nov 1997) |
| Broca's field | The posterior part of the inferior frontal gyrus of the left or dominant hemisphere, corresponding approximately to Brodmann's area 44; Broca identified this region as an essential component of the motor mechanisms governing articulated speech. Synonym: Broca's area, Broca's field, motor speech centre. (05 Mar 2000) |