Search results for "amine"

showing 10 items of 7299 documents

Visible light photocatalytic activity of macro-mesoporous TiO2-CeO2inverse opals

2018

Macro-mesoporous TiO2 inverse opal materials were synthesized and they were tested as photocatalysts under visible light irradiation. The influence of cerium oxide addition towards the Rhodamine B (RhB) photodegradation activity was evaluated. Structural, textural, spectral and surface properties of the TiO2-CeO2 inverse opal nanocomposites were studied by XRD, XPS, SEM, TEM, N2 adsorption-desorption, Diffuse Reflectance UV–vis and Photoluminescence spectroscopies. Compared to commercial TiO2 anatase, the macro-mesoporous TiO2 inverse opal exhibited six times higher kinetic rate constant in the RhB degradation under visible light irradiation. The good photocatalytic activity was related to …

AnataseCerium oxideRhodamine BGeneral Chemical EngineeringInorganic chemistryGeneral Physics and Astronomy02 engineering and technologyAdvanced oxidation process010402 general chemistryPorous structure01 natural sciencesNanomaterialschemistry.chemical_compoundPhysics and Astronomy (all)PhotocatalysiChemical Engineering (all)PhotocatalysisPhotodegradationChemistryPhotonic effectChemistry (all)General ChemistryCerium oxidePorous structures021001 nanoscience & nanotechnology0104 chemical sciencesChemical engineeringAdvanced oxidation process; Cerium oxide; Photocatalysis; Photonic effect; Porous structures; Rhodamine B; Titanium dioxide; Chemistry (all); Chemical Engineering (all); Physics and Astronomy (all)Titanium dioxidePhotocatalysisAdvanced oxidation proceTitanium dioxideSettore CHIM/07 - Fondamenti Chimici Delle Tecnologie0210 nano-technologyMesoporous materialVisible spectrum
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Effect of the addition of different doping agents on visible light activity of porous TiO2 photocatalysts

2018

Abstract The influence of the addition of different doping agents (N, W and Hf) on the macroporous TiO2 photoactivity toward the Rhodamine B degradation and ethanol photo-oxidation was evaluated. The samples were characterized by XRD, XPS, SEM, TEM, N2 adsorption-desorption, UV–vis Diffuse Reflectance and Photoluminescence spectroscopies to study also the changes in the physico-chemical properties due to the presence of dopants. The photonic effect and the high ordered porous structure of the macroporous TiO2 that lead to increase the path length of the light, were the key factors that allow to enhance the catalytic activity towards the dye and VOC degradation under visible and solar light …

AnataseMaterials sciencePhotoluminescenceIonic bondingVOCs remediation02 engineering and technology010402 general chemistry01 natural sciencesCatalysisCatalysichemistry.chemical_compoundPhotocatalysiRhodamine BPhysical and Theoretical ChemistryWater purificationDopantInverse opal materialProcess Chemistry and TechnologyDoping021001 nanoscience & nanotechnology0104 chemical scienceschemistryChemical engineeringTitanium dioxideSettore CHIM/07 - Fondamenti Chimici Delle TecnologieDiffuse reflection0210 nano-technologyVisible spectrumMolecular Catalysis
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Analgesic effect of intravenous ketamine in cancer patients on morphine therapy: A randomized, controlled, double-blind, crossover, double-dose study

2000

Pain not responsive to morphine is often problematic. Animal and clinical studies have suggested that N-methyl-d-aspartate (NMDA) antagonists, such as ketamine, may be effective in improving opioid analgesia in difficult pain syndromes, such as neuropathic pain. A slow bolus of subhypnotic doses of ketamine (0.25 mg/kg or 0.50 mg/kg) was given to 10 cancer patients whose pain was unrelieved by morphine in a randomized, double-blind, crossover, double-dose study. Pain intensity on a 0 to 10 numerical scale; nausea and vomiting, drowsiness, confusion, and dry mouth, using a scale from 0 to 3 (not at all, slight, a lot, awful); Mini-Mental State Examination (MMSE) (0- 30); and arterial pressur…

Anesthesiology and Pain MedicineOpioid responseKetamineNeurology (clinical)Cancer painAdverse effectNeuropathic painNMDA- antagonistNursing (all)2901 Nursing (miscellaneous)Randomized controlled epidemiologic study
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112 Workshop Summary: DOPAMINERGIC MECHANISMS OF PAIN CONTROL

2007

Anesthesiology and Pain MedicinePain controlbusiness.industryMedicineDopaminergic mechanismsbusinessNeuroscienceEuropean Journal of Pain
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Role of octreotide, scopolamine butylbromide, and hydration in symptom control of patients with inoperable bowel obstruction and nasogastric tubes: A…

2000

Bowel obstruction may be an inoperable complication in patients with end-stage cancer. Scopolamine butylbromide (SB) and octreotide (OCT) have been successfully used with the aim of reducing gastrointestinal (GI) secretions to avoid placement of a nasogastric tube (NGT); however, there have been no comparative studies concerning the efficacy of these drugs. Furthermore, there is little information about the role played by parenteral hydration in symptom control of these patients. In a prospective trial that involved all 17 inoperable bowel-obstructed patients presenting to our services with a decompressive NGT, patients were randomized to OCT 0.3 mg/day or SB 60 mg/day for 3 days through a …

Anesthesiology and Pain MedicineScopolamine butylbromideHydrationNeurology (clinical)OctreotideNursing (all)2901 Nursing (miscellaneous)Bowel obstructionCancer
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Acquired and Hereditary Angioedema: Pathogenesis and Therapy

1988

There are two main pathogenetic ways by which angioedema can develop. These pathways are completely different and lead to completely different diseases, which may have angioedema of the skin in common. Most cases of cutaneous angioedema develop with involvement of the mast cell and its mediators; especially histamine is considered to play a major role. The exact pathogenesis, however, is not known. This type of angioedema is assumed to be related to urticaria for several reasons: 1 Often it appears alternately with urticaria 2 It responds to antihistaminic drugs 3 The same causes may provoke either urticaria or angioedema

Angioedemabusiness.industryfood and beveragesMast cellmedicine.diseasePathogenesischemistry.chemical_compoundmedicine.anatomical_structurechemistryimmune system diseasesImmunologyHereditary angioedemamedicineAntihistaminic drugscardiovascular diseasesmedicine.symptomskin and connective tissue diseasesbusinessHistamine
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Central role of IL-6 and MMP-1 for cross talk between human intestinal mast cells and human intestinal fibroblasts.

2012

Mast cells (MC) are key effector cells in allergic reactions but also involved in host defence, tissue remodeling, angiogenesis, and fibrogenesis. Here, we show that human intestinal fibroblasts (FB) suppress apoptosis in human intestinal MC dependent on IL-6. Intestinal FB produced IL-6 upon direct stimulation by intestinal MC in co-culture or by MC mediators such as TNF-α, IL-1β, tryptase or histamine. MC incubated with IL-6 survived for up to 3 weeks similar to MC co-cultured with FB and MC survival could be blocked by neutralizing anti-IL-6 Abs. Moreover, FB stimulated by MC mediators upregulated their expression of matrix metalloproteinase-1 (MMP-1), a key fibrolytic enzyme. Noteworthy…

AngiogenesisCell SurvivalImmunologyInflammationTryptaseApoptosisCell CommunicationMatrix metalloproteinaseBiologychemistry.chemical_compoundDownregulation and upregulationmedicineImmunology and AllergyHumansMast CellsIntestinal MucosaInterleukin 6Protein Kinase InhibitorsFlavonoidsInterleukin-6HematologyReceptor Cross-TalkFibroblastsMolecular biologyCoculture TechniqueschemistryApoptosisImmunologybiology.proteinmedicine.symptomMatrix Metalloproteinase 1HistamineImmunobiology
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Development and validation of a liquid chromatography tandem mass spectrometry method for the analysis of beta-agonists in animal feed and drinking w…

2010

A reproducible, sensitive and selective multiresidue analytical method for seven beta-agonists: clenbuterol (CBT), clenpenterol (CPT), ractopamine (RTP), brombuterol (BBT), mabuterol (MBT), mapenterol (MPT), and hydroxymethylclenbuterol (HMCBT) was developed and validated by using liquid chromatography tandem mass spectrometry (LC-MS/MS) in feed and drinking water samples. The validation was achieved according to the criteria laid down in the Commission Decision 2002/657/EC, however it was necessary to use minimum required performance limits (MRPLs) proposed by the Community Reference Laboratories (CRLs) due to the lack of maximum residue limits (MRLs) for beta-agonists. By setting up these…

Animal feedBiochemistryHigh-performance liquid chromatographySensitivity and SpecificityAnalytical Chemistrychemistry.chemical_compoundLiquid chromatography–mass spectrometryTandem Mass SpectrometryWater SupplyPhenethylaminesSample preparationResidue (complex analysis)ChromatographyMabuterolOrganic ChemistryReproducibility of ResultsWaterGeneral MedicineAdrenergic beta-AgonistsAnimal FeedRactopaminechemistryEthanolaminesLinear ModelsWater qualityChromatography LiquidJournal of chromatography. A
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Ring splitting of azetidin-2-ones via radical anions

2012

The radical anions of azetidin-2-ones, generated by UV-irradiation in the presence of triethylamine, undergo ring-splitting via N-C4 or C3-C4 bond breaking, leading to open-chain amides. This reactivity diverges from that found for the neutral excited states, which is characterised by alpha-cleavage. The preference for beta-cleavage is supported by DFT theoretical calculations on the energy barriers associated with the involved transition states. Thus, injection of one electron into the azetidin-2-one moiety constitutes a complementary activation strategy which may be exploited to produce new chemistry.

AnionsAZETIDINESFree RadicalsUltraviolet RaysElectronVINYL ETHERSRing (chemistry)PhotochemistryBiochemistryPolarizable continuum modelchemistry.chemical_compoundN-(ARYLIDENE(OR ALKYLIDENE)AMINO)-2-AZETIDINONESQUIMICA ORGANICAMoietyReactivity (chemistry)BETA-LACTAM RINGPhysical and Theoretical ChemistryTriethylamineDNA PHOTOLYASEMolecular StructureSTEREOCONTROLLED SYNTHESISOrganic ChemistryTransition stateSTEREOSELECTIVE-SYNTHESISchemistryPOLARIZABLE CONTINUUM MODELExcited stateQuantum TheoryPHOTOCHEMICAL-REACTIONSBUILDING-BLOCKS
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Ability of the T cell-replacing polyanion dextran sulfate to trigger the alternate pathway of complement activation.

1973

Dextran sulfate (DS) consumed C3 in C4 deficient guinea pig serum. This temperature-dependent reaction required Mg++ ions and could therefore be blocked by EDTA. Isolated C3 was not influenced by DS, but serum factors were required for C3 consumption. The C3 proactivator as well as C3 were converted to their activated state by DS in guinea pig and human serum, as revealed by immunoelectrophoretical analysis. DS generated anaphylatoxin activity in serum. It is concluded that DS activates C3 via the alternate pathway of complement activation. This potency of the polyanion might serve as a tentative explanation for its T cell-replacing effect in an antibody-forming system, which was reported b…

AnionsAlternate pathwayT cellT-LymphocytesImmunologyBiologyHistamine ReleaseC3 proactivatorGuinea pigIleummedicineImmunology and AllergyPotencyHumansAnaphylatoxinAnaphylaxisImmunoelectrophoresisToxins BiologicalImmune SeraDextransComplement System ProteinsComplement systemKineticsmedicine.anatomical_structureDextran sulfateBiochemistryEuropean journal of immunology
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