Suppression

(redirected from fat suppression)
Also found in: Dictionary, Thesaurus, Medical.

suppression

[sə′presh·ən]
(computer science)
Removal or deletion usually of insignificant digits in a number, especially zero suppression.
Optional function in either on-line or off-line printing devices that permits them to ignore certain characters or groups of characters which may be transmitted through them.
(electronics)
Elimination of any component of an emission, as a particular frequency or group of frequencies in an audio-frequency of a radio-frequency signal.

Suppression

 

in genetics, a phenomenon that prevents the appearance of a character resulting from mutation and that causes partial or complete restoration of the normal phenotype.

Intragenic suppression is caused by a second (suppressor) mutation in the same gene in which the first (direct) mutation occurred. Intergenic suppression is caused by a second mutation in other genes that are located at a considerable distance from the suppressed gene. In intragenic suppression, a protein coded by a given gene can reacquire functional activity, although its original structure, in contrast to true reverse mutation, or reversion, is not restored. In intergenic suppression, the normal phenotype may be restored in some cases owing to mutations that permit other means of metabolism which do not require the functioning of the given gene. In other cases, the normal phenotype may be restored as a result of mutations that alter the process by which the genetic information of the mutant gene is realized.

The phenomenon of suppression, first discovered in 1920 by the American geneticist A. H. Sturtevant, is used to study the genetic code and other aspects of molecular genetics.

REFERENCE

Stent, G. Molekuliarnaia genetika. Moscow, 1974. Chapter 6. (Translated from English.)

I. I. TOLSTORUKOV

References in periodicals archive ?
Two independent radiologists performed the qualitative analysis for fat suppression uniformity and lesion conspicuity on T2 Dixon water-only and SPAIR images.
Caption: Figure 6: Magnetic resonance imaging findings (T1-weighted fat suppression gadolinium-enhanced image) after a drug holiday for six weeks.
At least one sequence without fat suppression is necessary to discern the typical appearance of marrow within the ossicle and to ensure the ossicle is not confused with a labral tear.
T2-weighted ((a) and (d)) and short T1 inversion recovery images (fat suppression method; (b), (c), (e), and (f)).
Chen, "Chemical shift and fat suppression magnetic resonance imaging of thymus in myasthenia gravis," Canadian Journal of Neurological Sciences, vol.
Reeder, "IDEAL imaging of the musculoskeletal system: robust water fat separation for uniform fat suppression, marrow evaluation, and cartilage imaging," The American Journal of Roentgenology, vol.
Magnetic resonance signal characteristics of lipomas are quite specific; lipomas have high signal intensity on T1 and T2 weighted images and their signal are suppressed by fat suppression sequence and by this way cardiac MRI become diagnostic in this case.
The hyperintense foci on T1-weighted images with fat suppression are due to small hemorrhages (Fig.
MRI fat suppression imaging has been reported to be useful, but angiomyolipoma, retroperitoneal liposarcoma, and some renal cell carcinomas also contain fat lesions; thus the preoperative diagnosis of XGP remains difficult [1, 5].
MRI of abdomen was done with 1.5T scanner (GE), The MRI protocol used an axial and coronal T2-weighted Half-Fourier Acquisition Single-Shot Turbo SE (HASTE) sequence, axial 2-D Fast Low Angle Shot (FLASH) plus fat suppression sequence, axial, sagittal, and coronal true fast sequence (TRUFI).
On MRI, hibernomas are often hyperintense on T1 and T2 weighted images with loss of some signal on fat suppression images; striking contrast enhancement and flow voids on T2 weighted images are other MR features that can be identified [1, 5].
Three dimensional gadolinium enhanced MR imaging of the breast: pulse sequence with fat suppression and magnetization transfer contrast.