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Mubin I. Syed Talal Akhter Uzma Wahid Azim Shaikh Mohsin Mirza Granville J. Tengesdahl 《Cardiovascular Revascularization Medicine》2012,13(2):141.e7-141.e11
Subclavian stenting can be extremely difficult in a hostile type II aortic arch (with acute angulation of the subclavian artery origin) or type III aortic arch. This case illustrates use of a low-profile system to gain through-and-through (flossing) access through the brachial artery to facilitate stenting via the femoral approach. This approach can be useful in patients with small brachial arteries where the risk of complication may be high if a standard vascular sheath was placed for stenting via the brachial approach. This technique also avoids the use of a surgical cut down. 相似文献
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Predictors of left ventricular systolic function recovery in the setting of sinus tachycardia in patients with cancer
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Faqir Muhammad Tuyen Duong Thanh Nguyen Ahmad Raza Bushra Akhtar 《Drug and chemical toxicology》2017,40(4):489-497
Nanotechnology has gained significant penetration to different fields of medicine including drug delivery, disease interrogation, targeting and bio-imaging. In recent years, efforts have been put forth to assess the use of this technology in biodetoxification. In this review, we will discuss the current status of nanostructured biomaterials/nanoparticle (NP)-based technologies as a candidate biodetoxifying agent. Patient hospitalization due to illicit drug consumption, suicidal attempts and accidental toxin exposure are major challenges in the medical field. Overdoses of drugs/toxic chemicals or exposure to bacterial toxins or poisons are conventionally treated by voiding the stomach, administering activated charcoal or by using specific antidotes, if the toxin is known. Because of the limitations of these methods for safe and effective detoxification, advancements in nanotechnology may offer novel ways in intoxication support by using nanostructured biomaterials, such as liposomes, micellar nanocarriers, liquid crystalline nanoassemblies and ligand-based NPs. 相似文献
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Syed Bilal Ahmad Fiona E. McNeill Soo Hyun Byun William V. Prestwich Carmel Mothersill Colin Seymour Andrea Armstrong Cristian Fernandez 《Dose-response》2013,11(4):513-531
In this study, we aimed to establish the emission of UV photons when HPV-G cells and associated materials (such as the cell substrate and cell growth media) are exposed to low LET radiation. The potential role of UV photons in the secondary triggering of biological processes led us to hypothesize that the emission and absorption of photons at this wavelength explain some radiation induced “bystander effects” that have previously been thought to be chemically mediated. Cells were plated in Petri-dishes of two different sizes, having different thicknesses of polystyrene (PS) substrate, and were exposed to β-radiation from 90Y produced by the McMaster Nuclear Reactor. UV measurements were performed using a single photon counting system employing an interference-type filter for selection of a narrow wavelength range, 340±5 nm, of photons. Exposure of the cell substrates (which were made of polystyrene) determined that UV photons were being emitted as a consequence of β particle irradiation of the Petri-dishes. For a tightly collimated β-particle beam exposure, we observed 167 photons in the detector per unit μCi in the shielded source for a 1.76 mm thick substrate and 158 photons/μCi for a 0.878 mm thick substrate. A unit μCi source activity was equivalent to an exposure to the substrate of 18 β-particles/cm2 in this case. The presence of cells and medium in a Petri-dish was found to significantly increase (up to a maximum of 250%) the measured number of photons in a narrow band of wavelengths of 340±5 nm (i.e. UVA) as compared to the signal from an empty control Petri-dish. When coloured growth medium was added to the cells, it reduced the measured count rate, while the addition of transparent medium in equal volume increased the count rate, compared to cells alone. We attribute this to the fact that emission, scattering and absorption of light by cells and media are all variables in the experiment. Under collimated irradiation conditions, it was observed that increasing cell density in medium of fixed volume resulted in a decrease in the observed light output. This followed a roughly exponential decline. We suggest that this may be due to increased scattering at the cell boundary and absorption of the UV in the cells. We conclude that we have measured UVA emitted by cells, cell medium and cell substrates as a consequence of their irradiation by low LET β-particle radiation. We suggest that these secondary UV photons could lead to effects in non-targetted cells. Some effects that had previously been attributed to a chemically mediated “bystander effect” may in fact be due to secondary UV emission. Some radiation bystander effect studies may require re-interpretation as this phenomenon of UV emission is further investigated. 相似文献
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