Search results for "Specificity."
showing 10 items of 2232 documents
Acoustic Radiation Force Impulse Elastography for the Non-Invasive Evaluation of Hepatic Fibrosis in Non-Alcoholic Fatty Liver Disease Patients: A Sy…
2015
Background In order to better monitor non-alcoholic fatty liver disease (NAFLD) patients at higher risk for HCC, there is a need for non-invasive diagnostic approaches to screen for the presence of advanced fibrosis in these patients. The aim of this systematic review and meta-analysis will be to evaluate the diagnostic efficacy of ARFI elastography in detecting hepatic fibrosis in NAFLD patients. Methods Relevant studies were identified from systematic searches of several major electronic databases (PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials). The primary outcomes were the summary sensitivity, summary specificity, the diagnostic odds ratio, and the summary recei…
Rilpivirine attenuates liver fibrosis through selective STAT1-mediated apoptosis in hepatic stellate cells
2020
ObjectiveLiver fibrosis constitutes a major health problem worldwide due to its rapidly increasing prevalence and the lack of specific and effective treatments. Growing evidence suggests that signalling through cytokine-activated Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathways regulates liver fibrosis and regeneration. Rilpivirine (RPV) is a widely used anti-HIV drug not reported to produce hepatotoxicity. We aimed to describe the potential hepatoprotective effects of RPV in different models of chronic liver injury, focusing on JAK-STAT signalling regulation.DesignThe effects of RPV on hepatic steatosis, inflammation and fibrogenesis were studied in a nut…
Computed tomographic imaging of hepatocellular carcinoma
2004
The ability of x-ray computed tomography (CT) to detect and characterize liver lesions has been one of the most studied issues in radiology during the past 20 years. Technological advances, combined with increased knowledge about the pathophysiological characteristics of these tumors, have dramatically increased the ability to detect and characterize large hepatocellular carcinomas (HCCs). Nonetheless, detection and characterization of early and small HCC lesions remains a difficult task. We review the imaging appearances of HCC on CT and discuss the sensitivity and specificity of computed tomographic imaging in screening patients with cirrhosis for HCC.
Incomplete sequence homogenization in 45S rDNA multigene families: intermixed IGS heterogeneity within the single NOR locus of the polyploid species …
2014
† Background and Aims Ribosomal sequences have become the classical example of the genomic homogenization of nuclear multigene families. Despite theoretical advantages and modelling predictions that support concerted evolution of the 45S rDNA, several reports have found intragenomic polymorphisms. However, the origins and causes of these rDNA polymorphisms are difficult to assess because seed plants show a wide range of 45S rDNA loci number variation, especially in polyploids. Medicago arborea is a tetraploid species that has a single 45S rDNA locus. This feature makes this species a suitable case study to assess the fate of ribosomal IGS homogenization in polyploid species showing nucleolu…
MRI of the pulmonary parenchyma.
1999
Imaging of the pulmonary parenchyma represents a unique challenge for MRI. Limited signal is caused by low proton density, susceptibility artifacts, and physiological motion (cardiac pulsation, respiration). Recently, further improvements in MRI techniques have widened the potential for investigations of pulmonary parenchymal disease. These include very short echo times, ultrafast turbo-spin-echo acquisitions, projection reconstruction technique, breathhold imaging, ECG triggering, contrast agents (perfusion imaging, aerosols), sodium imaging, hyperpolarized noble gas imaging, and oxygen enhancement. By using widely available techniques, MRI is helpful in the assessment of (a) acute alveoli…
Contrast-enhanced MRI of the lung
2000
The lung has long been neglected by MR imaging. This is due to unique intrinsic difficulties: (1) signal loss due to cardiac pulsation and respiration; (2) susceptibility artifacts caused by multiple air-tissue interfaces; (3) low proton density. There are many MR strategies to overcome these problems. They consist of breath-hold imaging, respiratory and cardiac gating procedures, use of short repetition and echo times, increase of the relaxivity of existing spins by administration of intravenous contrast agents, and enrichment of spin density by hyperpolarized noble gases or oxygen. Improvements in scanner performance and frequent use of contrast media have increased the interest in MR ima…
Latency versus persistence or intermittent recurrences: Evidence for a latent state of murine cytomegalovirus in the lungs
1997
The state of cytomegalovirus (CMV) after the resolution of acute infection is an unsolved problem in CMV research. While the term "latency" is in general use to indicate the maintenance of the viral genome, a formal exclusion of low-level persistent productive infection depends on the sensitivity of the assay for detecting infectious virus. We have improved the method for detecting infectivity by combining centrifugal infection of permissive indicator cells in culture, expansion to an infectious focus, and sensitive detection of immediate-early RNA in the infected cells by reverse transcriptase PCR. A limiting-dilution approach defined the sensitivity of this assay. Infectivity was thereby …
Evaluation of soluble CD 14 and neopterin as serum parameters of the inflammatory activity of pulmonary sarcoidosis.
1992
CD14 represents the most specific marker for monocytes/macrophages. It has been demonstrated in vitro that monocytes/macrophages lose this antigen upon activation. Results of studies investigating the expression of membrane-bound CD14 on the surface of monocytes/macrophages in sarcoidosis patients are controversial. To investigate whether the soluble form of CD14 reflects monocyte/macrophage activation in sarcoidosis, serum levels of soluble CD14 were determined concurrently with other serum markers of monocyte/macrophage activation (neopterin, angiotensin-converting enzyme) in 50 consecutive patients with bioptically confirmed sarcoidosis. The patients were allocated to three groups accord…
A smart and operator independent system to delineate tumours in Positron Emission Tomography scans
2018
Abstract Positron Emission Tomography (PET) imaging has an enormous potential to improve radiation therapy treatment planning offering complementary functional information with respect to other anatomical imaging approaches. The aim of this study is to develop an operator independent, reliable, and clinically feasible system for biological tumour volume delineation from PET images. Under this design hypothesis, we combine several known approaches in an original way to deploy a system with a high level of automation. The proposed system automatically identifies the optimal region of interest around the tumour and performs a slice-by-slice marching local active contour segmentation. It automa…
An update on the xenograft and mouse models suitable for investigating new therapeutic compounds for the treatment of B-cell malignancies
2008
B-cell malignancies account for over the 90% of all lymphoid neoplasms. The clonal proliferations of B-cells show a high degree of variation in terms of clinical and presenting features, histopathology, immuophenotype, and genetics. Primary tumor samples are useful for examining the characteristics of a patients own tumor, although both primary leukemic cells and cell lines provide an initial step for screening novel compounds for their activity in some hematological malignancies, they should be followed by models in intact animals. In this review, we try to summarize the animal models generated to study B-cell malignancies, in particular, B-cell lymphoma, B-cell CLL and MM that represent t…