Search results for "Contrast"

2017

The current study used event-related brain potentials (ERPs) and behavioral measures to examine effects of genre awareness on sentence processing and evaluation. We hypothesized that genre awareness modulates effects of genre-typical manipulations. We manipulated instructions between participants, either specifying a genre (poetry) or not (neutral). Sentences contained genre-typical variations of semantic congruency (congruent/incongruent) and morpho-phonological features (archaic/contemporary inflections). Offline ratings of meaningfulness (n=64/group) showed higher average ratings for semantically incongruent sentences in the poetry vs. neutral condition. ERPs during sentence reading (n=2…

Magnetic Resonance Imaging of Nonhepatocellular Malignancies in Chronic Liver Disease.

2021

Hepatocellular carcinoma (HCC) is the most common liver malignancy associated with chronic liver disease. Nonhepatocellular malignancies may also arise in the setting of chronic liver disease. The imaging diagnosis of non-HCC malignancies may be challenging. Non-HCC malignancies in patients with chronic liver disease most commonly include intrahepatic cholangiocarcinoma and combined hepatocellular-cholangiocarcinoma, and less commonly hepatic lymphomas and metastases. On MR imaging, non-HCC malignancies often demonstrate a targetoid appearance, manifesting as rim arterial phase hyperenhancement, peripheral washout, central delayed enhancement, and peripheral restricted diffusion. When apply…

Selbstorganisierende neuronale Netze zur automatischen Detektion und Klassifikation von Kontrast(mittel)-verstärkten Läsionen in der dynamischen MR-M…

2005

Purpose: Investigation and statistical evaluation of "Self-Organizing Maps," a special type of neural networks in the field of artificial intelligence, classifying contrast enhancing lesions in dynamic MR-mammography. Material and Methods: 176 investigations with proven histology after core biopsy or operation were randomly divided into two groups. Several Self-Organizing Maps were trained by investigations of the first group to detect and classify contrast enhancing lesions in dynamic MR-mammography. Each single pixel's signal/time curve of all patients within the second group was analyzed by the Self-Organizing Maps. The likelihood of malignancy was visualized by color overlays on the MR-…

Confocal laser endoscopy for diagnosing intraepithelial neoplasias and colorectal cancer in vivo

2004

Background & Aims: Aconfocal laser endoscopy system has recently been developed that may allow subsurface imaging of living cells in colonic tissue in vivo. The aim of the present study was to assess its potential for prediction of histology during screening colonoscopy for colorectal cancer. Methods: Twenty-seven patients underwent colonoscopy with the confocal endoscope using acriflavine hydrochloride or fluorescein sodium with blue laser illumination. Furthermore, 42 patients underwent colonoscopy with this system using fluorescein sodium. Standardized locations and circumscript lesions were examined by confocal imaging before taking biopsy specimens. Confocal images were graded accordin…

Endothelial capillaries chemotactically attract tumour cells.

2001

Directional migration of capillaries towards tumour implants is generally assumed to be regulated by chemotaxis. Preliminary evidence has also been presented for the existence of a reverse chemotactic signalling pathway, with capillaries attracting tumour cells via paracrine factors. By using a variety of endothelial cell types and tumour cell lines, this study has systematically investigated chemotaxis between endothelial cells and tumour cells in two- and three-dimensional systems. Checkerboard analysis revealed faint attraction of human umbilical vein endothelial cells (HUVECs), but not porcine aortic endothelial cells (PAECs), by tumour cells. In reverse, both PAECs and HUVECs potently …

Unmasking epithelial-mesenchymal transition in a breast cancer primary culture: a study report

2012

Abstract Background Immortalized cancer cell lines are now well-established procedures in biomedicine for a more complete understanding of cellular processes in cancer. However, they are more useful in preparation of fresh tumour tissue, in order to obtain cancer cells with highly preserved individual tumour properties. In the present study we report an analytical investigation on a breast cancer primary cell culture isolated from a surgical specimen obtained from a patient with an infiltrating ductal carcinoma. The objective of the research was to reveal unrecognized aspects of neoplastic cells, typical of the tumour from where the cells were derived, but masked in fixed tissue sections, i…

Guidelines for the diagnosis and management of intrahepatic cholangiocarcinoma

2014

Brain iron deposition after Ferumoxytol-enhanced MRI: A study of Porcine Brains

2020

Recent evidence of gadolinium deposition in the brain has raised safety concerns. Iron oxide nanoparticles are re-emerging as promising alternative MR contrast agents, because the iron core can be metabolized. However, long-term follow up studies of the brain after intravenous iron oxide administration have not been reported thus far. In this study, we investigated, if intravenously administered ferumoxytol nanoparticles are deposited in porcine brains. Methods: In an animal care and use committee-approved prospective case-control study, ten Gottingen minipigs received either intravenous ferumoxytol injections at a dose of 5 mg Fe/kg (n=4) or remained untreated (n=6). Nine to twelve months …

Confocal laser endomicroscopy.

2005

A miniaturized confocal microscope was developed that could be integrated in the distal tip of a conventional colonoscope. With this technique, denoted confocal endomicroscopy, subsurface analysis of the gut mucosa and in-vivo histology during ongoing endoscopy are possible in full resolution by point scanning laser analysis. The diagnostic spectrum of confocal endomicroscopy is expanding from screening and surveillance for colorectal cancer to Barrett's esophagus, Helicobacter pylori-associated gastritis, and gastric cancer. The new detailed images seen with confocal laser endomicroscopy allow a unique look on cellular structures at and below the surface of the gut. This review describes t…

2015

Background Accurate evaluation of immunostained histological images is required for reproducible research in many different areas and forms the basis of many clinical decisions. The quality and efficiency of histopathological evaluation is limited by the information content of a histological image, which is primarily encoded as perceivable contrast differences between objects in the image. However, the colors of chromogen and counterstain used for histological samples are not always optimally distinguishable, even under optimal conditions. Methods and Results In this study, we present a method to extract the bivariate color map inherent in a given histological image and to retrospectively o…