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" no prazo de Papéis
Beatrice Bocca et al.
Annali dell'Istituto superiore di sanita, 41(2), 197-203 (2005-10-26)
The haematic concentration of 26 metals and the oxidative damage in 60 patients (20 males and 40 females) affected by Alzheimer's disease and 44 healthy individuals (33 males and 11 females) were compared. In patients, the following significant (p <
R K Sahoo et al.
Journal of nanoscience and nanotechnology, 14(6), 4595-4601 (2014-04-18)
The dewetting of a low melting point metal thin film deposited on silicon substrates was studied. The experimental results suggest that the change in the growth temperature affects the nanostructures that form. Based on the experimental results, the temperature which
Chengyong Li et al.
Journal of nanoscience and nanotechnology, 13(3), 2272-2275 (2013-06-13)
Mesoporous Si-C-O fibers were fabricated by air activation of a kind of carbon-rich SiC-C fibers at 600 degrees C. The SiC-C fibers were prepared from the hybrid precursor of polycarbosilane and pitch through melt-spinning, air curing and pyrolysis in nitrogen.
Alexandra E Porter
Micron (Oxford, England : 1993), 37(8), 681-688 (2006-04-25)
Silicon plays an important role in bone mineralization and formation and is therefore incorporated into a wide variety of medical implants and bone grafts used today. The significance of silicon (Si) can be understood through an analysis of the mechanisms
David J Savage et al.
Current opinion in pharmacology, 13(5), 834-841 (2013-07-13)
Biomedical applications of porous silicon include drug delivery, imaging, diagnostics and immunotherapy. This review summarizes new silicon particle fabrication techniques, dynamics of cellular transport, advances in the multistage vector approach to drug delivery, and the use of porous silicon as
Hirohito Nishimura et al.
The Journal of cell biology, 202(6), 967-983 (2013-09-18)
Fluorescence microscopy is used extensively in cell-biological and biomedical research, but it is often plagued by three major problems with the presently available fluorescent probes: photobleaching, blinking, and large size. We have addressed these problems, with special attention to single-molecule
Guo-Jun Zhang et al.
Analytica chimica acta, 749, 1-15 (2012-10-06)
Over the past decade, silicon nanowire (SiNW) biosensors have been studied for the detection of biological molecules as highly sensitive, label-free, and electrical tools. Herein we present a comprehensive review about the fabrication of SiNW biosensors and their applications in
L H Jones
The American journal of clinical nutrition, 31(10 Suppl), S94-S98 (1978-10-01)
Plant cell walls that are secondarily thickened contain silicon and metal cations. The silicon occurs predominantly as silica (SiO2.nH2O) deposited in intimate association with the organic components of the walls and, according to recent evidence, as an integral constituent of
Nathaporn Promros et al.
Journal of nanoscience and nanotechnology, 13(5), 3577-3581 (2013-07-19)
n-Type nanocrystalline (NC) FeSi2/p-type Si heterojunctions, which were prepared by pulsed laser deposition, were evaluated as a near infrared photodiode. The built-in potential was estimated to be approximately 1.1 eV from the capacitance-voltage measurement. These junctions showed a rectifying behavior
Takashi Abe et al.
Journal of neuroscience research, 70(3), 447-450 (2002-10-23)
To investigate the possible role of oxidative RNA damage in the pathogenesis of Alzheimer's disease (AD), the concentrations of the oxidative stress marker 8-hydroxyguanosine (8-OHG) were measured in the cerebrospinal fluid (CSF) and the serum of patients with AD and
Anna Walter et al.
Neurobiology of aging, 25(10), 1299-1303 (2004-10-07)
Experimental and clinical studies give evidence for breakdown of membrane phospholipids during neurodegeneration. In the present study, we measured the levels of glycerophosphocholine (GPCh), phosphocholine (PCh), and choline, that is, water-soluble metabolites of phosphatidylcholine (PtdCho), in human cerebrospinal fluid (CSF).
M Naoi et al.
Mechanisms of ageing and development, 111(2-3), 175-188 (2000-02-03)
Dopamine neurons in the substantia nigra of human brain are selectively vulnerable and the number decline by aging at 5-10% per decade. Enzymatic and non-enzymatic oxidation of dopamine generates reactive oxygen species, which induces apoptotic cell death in dopamine neurons.
V Calabrese et al.
Neurochemical research, 28(9), 1321-1328 (2003-08-27)
Recent studies suggest that NO and its reactive derivative peroxynitrite are implicated in the pathogenesis of multiple sclerosis (MS). Patients dying with MS demonstrate increased astrocytic inducible nitric oxide synthase activity, as well as increased levels of iNOS mRNA. Peroxynitrite
Cells under pressure.
Allison Doerr
Nature methods, 10(9), 818-819 (2013-10-22)
Keith R Martin
Metal ions in life sciences, 13, 451-473 (2014-01-29)
Silicon is the second most abundant element in nature behind oxygen. As a metalloid, silicon has been used in many industrial applications including use as an additive in the food and beverage industry. As a result, humans come into contact
C E Shaw et al.
Journal of neurology, 242(2), 53-58 (1995-01-01)
Magnetic resonance imaging of multiple sclerosis (MS) patients often shows active inflammatory lesions despite clinical remission. No immunological marker of disease activity has been identified in these patients. Concentrations of neopterin, interleukin-2 (IL-2), soluble interleukin-2 receptor (sIL-2R) and tumour necrosis
S Engelborghs et al.
Neurochemical research, 28(8), 1145-1150 (2003-07-02)
To study changes in amino acid metabolism and biogenic amines in Parkinson's disease, we set up a prospective study and measured biogenic amines, their main metabolites, and 22 different amino acids, in cerebrospinal fluid of Parkinson's disease patients (n =
Emil Rudobeck et al.
Radiation research, 181(4), 407-415 (2014-03-15)
An unavoidable complication of space travel is exposure to radiation consisting of high-energy charged particles (HZE), such as Fe and Si nuclei. HZE radiation can affect neuronal functions at the level of the synapse or neuronal soma without inducing significant
P A LeWitt et al.
Neurology, 42(11), 2111-2117 (1992-11-01)
We used two analytic methods (a multichannel coulometric electrode array with high-performance liquid chromatography, and gas chromatography-mass spectrophotometry) to measure CSF dopamine (DA) and its metabolites in mildly affected, unmedicated subjects with Parkinson's disease (PD). The mean (+/- SD) concentration
Norbert W Lutz et al.
PloS one, 2(7), e595-e595 (2007-07-06)
Multiple sclerosis (MS), an inflammatory disease of the central nervous system, manifests itself in numerous forms and stages. A number of brain metabolic alterations have been reported for MS patients vs. control subjects. However, metabolite profiles of cerebrospinal fluid (CSF)
Dae-Hee Kim et al.
Journal of nanoscience and nanotechnology, 13(5), 3564-3567 (2013-07-19)
The initial reaction of dimethylaluminum isopropoxide (Al(CH3)2OC3H7, DMAI) with a fully hydrogen-terminated Si (001) surface for aluminum oxide thin-film growth was investigated using density functional theory. Al-C and Al-O bonds of the adsorbed DMAI were easily broken to produce unimethylaluminum
Prashanta Dhoj Adhikari et al.
Journal of nanoscience and nanotechnology, 13(7), 4587-4592 (2013-08-02)
Multi-walled carbon nanotubes (MWCNTs) were grown using iron oxide nanoclusters (Nc) assisted by self-assembled monolayer (SAM) on substrate. The amine-terminated SAM fabricated on silicon substrate (APTMS/SI) was carried out by UV-treatment and immersed into the FeCI3/HCI aqueous solution. Then, Nc
K W Urban et al.
Physical review letters, 110(18), 185507-185507 (2013-05-21)
Newly developed achromatic electron optics allows the use of wide energy windows and makes feasible energy-filtered transmission electron microscopy (EFTEM) at atomic resolution. In this Letter we present EFTEM images formed using electrons that have undergone a silicon L(2,3) core-shell
Nathan Marchack et al.
Annual review of chemical and biomolecular engineering, 3, 235-262 (2012-06-14)
The invention of the transistor followed by more than 60 years of aggressive device scaling and process integration has enabled the global information web and subsequently transformed how people communicate and interact. The principles and practices built upon chemical processing
Jeong Min Lee et al.
Journal of nanoscience and nanotechnology, 13(11), 7741-7744 (2013-11-20)
This study demonstrated meso/micro/nano-ultraprecision machining through electrochemical reactions using intermittent DC pulses. The experiment focused on two machining methods: (1) pulse electrochemical polishing (PECP) of stainless steel, and (2) pulse electrochemical nano-patterning (PECNP) on a silicon (Si) surface, using atomic
E O Uthus et al.
The Journal of nutrition, 126(9 Suppl), 2452S-2459S (1996-09-01)
Circumstantial evidence suggests that aluminum, arsenic, bromine, cadmium, germanium, lead, lithium, nickel, rubidium, silicon, tin and vanadium are essential. The evidence is most compelling for arsenic, nickel, silicon and vanadium. The estimated daily dietary intakes for these elements are arsenic
Giovanni Forte et al.
Annali dell'Istituto superiore di sanita, 41(2), 213-216 (2005-10-26)
Although some studies suggested a link between exposure to trace elements and development of multiple sclerosis (MS), clear information on their role in the aetiology of MS is still lacking. In this study the concentrations of Al, Ba, Be, Bi
Muhammad Ahsan Farooq et al.
Ecotoxicology and environmental safety, 96, 242-249 (2013-08-06)
Biotic systems face immense environmental hazards such as accumulation of heavy metals, particularly in agricultural ecosystems that might cause deterioration of yield and quality of crops. In this study, we evaluated the role of silicon (Si) in alleviating the heavy
Xuyang Liu et al.
Environmental pollution (Barking, Essex : 1987), 184, 570-578 (2013-11-05)
Surface transformation can affect the stability, reactivity, and toxicity of titanium dioxide (TiO2) nanoparticles (NPs) in water environments. Herein, we investigated the release kinetics of Si impurity frequently introduced during NP synthesis and the resulting effect on TiO2 NP transformation
E Epstein
Proceedings of the National Academy of Sciences of the United States of America, 91(1), 11-17 (1994-01-04)
Silicon is the second most abundant element in soils, the mineral substrate for most of the world's plant life. The soil water, or the "soil solution," contains silicon, mainly as silicic acid, H4SiO4, at 0.1-0.6 mM--concentrations on the order of
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