Search results for "stent"
showing 10 items of 1166 documents
carotid endarterectomy versus stenting in patients with contralateral carotid artery occlusion
2009
Results of Angioplasty With Double-Layer Mesh Stent and Protection Systems of the Extra- and Intracranial Dissection of Cephalic Arteries
2023
Purpose: Although a majority of cervical artery dissections can be managed conservatively, patients presenting with cerebral embolization or significant stenosis require a more aggressive approach. However, complications associated with endovascular repair are quite frequent and optimal interventional technique still remains to be established. Materials and methods: The aim of this post hoc survey was to analyze results of endovascular treatments for symptomatic dissections of the internal carotid and vertebral arteries, which were performed under protection and with the use of double-layer mesh stents. During endovascular procedure catheters, stents and protection systems were tailored acc…
Carotid endarterectomy versus stenting in patients with contralateral carotid artery occlusion
2012
Aim. The aim of this prospective study was to compare outcomes after CEA and CAS in patients with contralateral carotid artery occlusion. Methods. Between 2004 and 2009, 527 consecutive patients underwent CEA (N.=281) or CAS (N.=246) for severe stenosis of internal carotid artery (ICA). Of them, 85 (16.1%) were identified with contralateral carotid artery occlusion. CEA was performed in 31(36.4%) patients with contralateral ICA occlusion, and 15 (48.4%) were symptomatic. Intraoperative shunts were placed in 12% versus 41.9% (P<0.001) patients with patent (N.=250) or occluded contralateral ICA (N.=31). Fifty-four (63.5%) patients with contralateral ICA occlusion underwent CAS with distal pro…
Polycyclic aromatic hydrocarbons (PAHs) in indoor emission from decorative candles
2011
Abstract This study investigates PAHs indoor emissions from burning decorative candle in an indoor environment because emissions from burning wax in home have rarely been addressed. A total of 12 air samples were collected during the entire burning period of the decorative candles. Particulate and gaseous PAHs emissions were simultaneously measured by passing effluent through a filter (to collect particulate-phase PAHs), a cold trap and ORBO 43 tubes (to capture gaseous-phase PAHs). Analysis involved ultrasound extraction, followed by gas chromatography–mass spectrometry (GC–MS). The measured total PAHs concentration (particulate + aqueous phase + gas phases) for the candles, reported as ma…
Macroscopic persistent currents in YBa2Cu3O7
1988
Persistent currents in polycrystalline YBa2Cu3O7 rings have been investigated by measuring the spatial distribution of the magnetic flux trapped in field-cooled samples. The results unambiguously show that macroscopic persistent ring currents exist. The critical current density depends very sensitively on the sample quality, reachingj c ≈250 A/cm2 at 77 K for our best samples.
Hybrid Lattice Boltzmann/Dynamic Self-Consistent Field Simulations of Microphase Separation and Vesicle Formation in Block Copolymer Systems
2011
We present a hybrid numerical method to introduce hydrodynamics in dynamic self-consistent field (SCF) studies of inhomogeneous polymer systems. It solves a set of coupled dynamical equations: The ...
Contamination from polycyclic aromatic hydrocarbons (PAHs) in the soil of a botanic garden localized next to a former manufacturing gas plant in Pale…
2010
The Botanical Garden lies within the city of Palermo, a few meters away from one of the largest unused Manufacturing Gas Plant in Sicily. The total concentrations of PAHs (23 compounds) in the soil of Botanical Garden ranged from 947 to 18,072 microg/kg. The wide range of PAH concentrations (RSD=84%) found in the soil samples indicates heterogeneous levels of contamination in the area and this can be explained by considering the different tree distributions which prevents the homogeneous deposition of pollutants on the soil. Soils collected in the Botanical Garden generally showed the highest PAH concentrations, being almost 2-3 times higher than the concentration samples obtained in the ur…
Oxygen-containing polycyclic aromatic hydrocarbons (OPAHs) in urban soils of Bratislava, Slovakia: patterns, relation to PAHs and vertical distributi…
2011
Abstract We determined concentrations, sources, and vertical distribution of OPAHs and PAHs in soils of Bratislava. The ∑14 OPAHs concentrations in surface soil horizons ranged 88–2692 ng g−1 and those of ∑34 PAHs 842–244,870 ng g−1. The concentrations of the ∑9 carbonyl-OPAHs (r = 0.92, p = 0.0001) and the ∑5 hydroxyl-OPAHs (r = 0.73, p = 0.01) correlated significantly with ∑34 PAHs concentrations indicating the close association of OPAHs with parent-PAHs. OPAHs were quantitatively dominated by 9-fluorenone, 9,10-anthraquinone, 1-indanone and benzo[a]anthracene-7,12-dione. At several sites, individual carbonyl-OPAHs had higher concentrations than parent PAHs. The concentration ratios of se…
Chemical speciation of polycyclic aromatic hydrocarbons in sediments: partitioning and extraction of humic substances.
2010
The primary objective of this study was to examine the chemical speciation of polycyclic aromatic hydrocarbons (PAHs) found in sediments endowed with different characteristics. To achieve this purpose and because the nature of the sediments influences the distribution of PAHs, we have analyzed four different types of sediments. To study the role of organic matter in the sequestration of PAHs, we fractionated humic substances into humic acids and humin–mineral fractions. After their separation and purification, the humic components were examined for their sorptive reactivity by extracting them with organic solvents; these extracts were subsequently subjected to GC/MS analysis. Our results sh…