Search results for " Vessel"

Improved technique for sheath supported contralateral limb gate cannulation in endovascular abdominal aortic aneurysm repair

2019

Summary: Background: To present a technique of sheath supported contralateral limb gate (CLG) cannulation of modular bifurcated stent-graft in endovascular abdominal aortic repair. Materials and methods: After totally percutaneous bilateral femoral access, the 9F introducer sheath is exchanged to a 30 cm 12 fr introducer sheath over a stiff wire contralateral to the intended main stent-graft insertion side and advanced into the aorta below the lowest renal artery. Parallel to the stiff wire within the sheath an additional standard J-tip guidewire with a 5 fr Pigtail angiographic catheter is advanced to the level of the renal arteries. After main body deployment, the 12 fr introducer sheath…

A Comparative Study on Feature Selection for Retinal Vessel Segmentation Using FABC

2009

This paper presents a comparative study on five feature selection heuristics applied to a retinal image database called DRIVE. Features are chosen from a feature vector (encoding local information, but as well information from structures and shapes available in the image) constructed for each pixel in the field of view (FOV) of the image. After selecting the most discriminatory features, an AdaBoost classifier is applied for training. The results of classifications are used to compare the effectiveness of the five feature selection methods.

Unsupervised recognition of retinal vascular junction points.

2014

Landmark points in retinal images can be used to create a graph representation to understand and to diagnose not only different pathologies of the eye, but also a variety of more general diseases. Aim of this paper is the description of a non-supervised methodology to distinguish between bifurcations and crossings of the retinal vessels, which can be used in differentiating between arteries and veins. A thinned representation of the binarized image, is used to identify pixels with three or more neighbors. Junction points are classified into bifurcations or crossovers according to their geometrical and topological properties. The proposed approach is successfully compared with the state-of-t…

On the Reduction of Power Consumption in Vortexing Unbaffled Bioslurry Reactors

2020

Bioremediation of polluted soils via bioslurry reactors is an interesting option among those available nowadays, especially when recalcitrant pollutants are present. Vortexing unbaffled stirred tanks may be a valuable choice to this purpose as they were recently found to be more efficient than baffled vessels for solid suspension processes where mixing time is not a controlling factor. When operated at sufficiently high agitation speeds, the central vortex bottom reaches the impeller and air bubbles start to be distributed throughout the system, thus avoiding any sparger and related clogging issues. In the present work, a vortexing unbaffled stirred tank with solid loadings ranging from 2.5…

Riflessione sulle misure di prevenzione dell'inquinamento marino dopo l'incidente della Prestige

2003

En este capítulo se analizan las medidas de prevención de la contaminación marina, en concreto, de la contaminación por hidrocarburos procedentes de buque que existían antes del accidente del superpetrolero Prestige. A continuación, se analizan las medidas adoptadas por el Estado ribereño para evitar accidentes similares en el futuro, así como las medidas propuestas por la Comisión Europea.

Transient reduction of the ocular perfusion pressure and the oscillatory potentials of the ERG

2005

Abstract Purpose. To evaluate the changes of the Oscillatory Potentials (OPs) of Electroretinogram (ERG) caused by short-term hypertension in human subjects, and their relationship with ocular perfusion pressure (OPP). Methods. Suction cup technique in 12 normal volunteers with OPs simultaneously recording. Results. Scotopic and photopic OPs were altered during OPP drop. Scotopic OPs showed more sensitiveness, with higher reduction (from 21% to 47%), when compared to the basal value, than in photopic recordings (from 14% to 34%). In both conditions, the relationship between OPP and OPs presented a steady amplitude before the trough after the +30 step, and rapid recovery after OPP normalisat…

Apoptosis causes lumen formation during angiogenesis in vitro.

2002

Paraoxonase-2 Reduces Oxidative Stress in Vascular Cells and Decreases Endoplasmic Reticulum Stress–Induced Caspase Activation

2007

Background— In the vascular system, elevated levels of reactive oxygen species (ROS) produce oxidative stress and predispose to the development of atherosclerosis. Therefore, it is important to understand the systems producing and those scavenging vascular ROS. Here, we analyzed the ROS-reducing capability of paraoxonase-2 (PON2) in different vascular cells and its involvement in the endoplasmic reticulum stress pathway known as the unfolded protein response. Methods and Results— Quantitative real-time polymerase chain reaction and Western blotting revealed that PON2 is equally expressed in vascular cells and appears in 2 distinct glycosylated isoforms. By determining intracellular ROS, we…

Giant bronchogenic cyst within the aortic wall mimicking symptoms of acute type A aortic dissection.

2010

Mediastinal lymph node staging with transesophageal echography in cancer of the lung.

1990

Transesophageal echography (TEE) was used prospectively to study mediastinal lymph node enlargement in 23 patients with cancer of the lung. The findings were validated blindly by comparison with computed tomography (CT, n = 23) and pathological N classification after curative surgery (n = 9). Lymph nodes larger than 1 cm were defined as pathologically enlarged. In the upper mediastinum, 22% (8 vs 36), in the lower mediastinum including the subaortic region 112% (37 vs 33) and in the hilar region 67% (6 vs 9) of enlarged lymph nodes diagnosed by CT were detected by TEE. A pathological study in 9 patients demonstrated true positive findings in 2 vs 1, true negatives in 4 vs 5, false positives…