PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 3487957

Dynamic-range compression in surface-coil MRI.

R B Lufkin·T Sharpless·B Flannigan·W Hanafee
View original source ↗Export metadata ↓

Abstract

The large dynamic range in signal intensity present in MR surface-coil images makes proper windowing and photography difficult. By removing the low-spatial frequency information caused by variations in surface-coil field intensity from the high-spatial frequency information containing the image data, a considerable compression of this dynamic range of signal intensity is possible. To accomplish this, a technique was implemented on a digital computer for use with MR surface-coil image data. The compression was done as a postprocessing option after the patient scan had been completed and therefore did not alter actual scan times. Although the image signal-to-noise was not altered, the ease of photography for most images was improved. Thus, digital dynamic-range compression is a practical technique to aid in surface-coil MRI studies.

Explore related subjects

AdenocarcinomaHumansLumbar VertebraeMagnetic Resonance SpectroscopyModels, StructuralSkull NeoplasmsTemporal BoneJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

R B Lufkin, T Sharpless, B Flannigan, W Hanafee. 1986. Dynamic-range compression in surface-coil MRI.. https://doi.org/10.2214/ajr.147.2.379

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2001

Interaction of Galpha 12 and Galpha 13 with the cytoplasmic domain of cadherin provides a mechanism for beta -catenin release.

The G12 subfamily of heterotrimeric G proteins, comprised of the alpha-subunits Galpha12 and Galpha13, has been implicated as a signaling component in cellular processes ranging from cytoskeletal changes to cell growth and oncogenesis. In an attempt to elucidate specific roles of this subfamily in cell regulation, we sought to identify molecular targets of Galpha12. Here we show a specific interaction between the G12 subfamily and the cytoplasmic tails of several members of the cadherin family of cell-surface adhesion proteins. Galpha12 or Galpha13 binding causes dissociation of the transcriptional activator beta-catenin from cadherins. Furthermore, in cells lacking the adenomatous polyposis coli protein required for beta-catenin degradation, expression of mutationally activated Galpha12 or Galpha13 causes an increase in beta-catenin-mediated transcriptional activation. These findings provide a potential molecular mechanism for the previously reported cellular transforming ability of the G12 subfamily and reveal a link between heterotrimeric G proteins and cellular processes controlling growth and differentiation.

Adenocarcinoma↗
PubMed1992

Effect of phosphoramidon on big endothelin-2 conversion into endothelin-2 in human renal adenocarcinoma (ACHN) cells. Analysis of endothelin-2 biosynthetic pathway.

The biosynthetic pathway of endothelin (ET)-2 was analyzed in cultured ACHN cells. In the supernatant, we detected three ET-2-related peptides, ET-2, big ET-2(1-38) and big ET-2(22-38). Phosphoramidon decreased the amount of ET-2 and increased that of big ET-2(1-38) dose-dependently. The amount of big ET-2(1-37) did not significantly change. These results suggest that big ET-2 is composed of 38 and not 37 amino acid residues, and that a putative ET-2-converting enzyme (ECE-2) should be classified as a phosphoramidon-sensitive neutral metalloprotease, bearing a resemblance to the putative ET-1-converting enzyme (ECE-1) in endothelial cells.

Adenocarcinoma↗
PubMed1992

Adenocarcinoma of the proximal small intestine. A marker for familial and multicentric cancer?

BACKGROUND: Adenocarcinoma of the small intestine is uncommon. The Hawaii Tumor Registry (HTR) has identified 49 of these tumors since 1960, and the Japan-Hawaii Cancer Study (JHCS) has identified only four of these tumors among a cohort of 8006 Hawaiian-Japanese men followed up for a period of 22 years. Each of the four men reported by the JHCS had multicentric gastrointestinal cancers. METHODS: Newly diagnosed cancers are recorded separately by the HTR and JHCS, and linkage is maintained between the two files. Family histories are available from the JHCS, and these are supplemented by a state population file maintained by the Department of Genetics, University of Hawaii. RESULTS: Five men, all Japanese, were found to have carcinoma of the proximal small intestine. Each had multicentric carcinomas of the gastrointestinal tract. Carcinoma of the stomach and colon was found in the primary relatives of each of four men whose families lived in Hawaii. CONCLUSIONS: The familial clustering of uncommon neoplasms (small bowel carcinoma and multicentric large bowel carcinoma), and the concurrence of gastric and colonic carcinoma suggests that these subjects have a genetic trait that increases susceptibility to a broad range of carcinogens.

Adenocarcinoma↗