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Results 101 - 150 of 1643
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Zicker Steven C - - 2010
To determine the pharmacokinetics of DL-α-lipoic acid in dogs when administered at 3 dosages via 3 methods of delivery. 27 clinically normal Beagles. In a 3 × 3 factorial Latin square design, 3 dosages (2.5, 12.5, and 25 mg/kg) of DL-α-lipoic acid were administered orally in a capsule form and ...
Luo Heng - - 2010
Antioxidant properties of 46 lichen species collected from high-UV exposed alpine areas of southwestern China were evaluated for their therapeutic utilization. Anti-linoleic acid peroxidation activity, 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity, reducing power and the total phenolic contents were assessed in methanol extract of the lichens in vitro. Extracts of Peltigera ...
Mukherjee Debajyoti - - 2010
Betulinic acid (pentacyclic triterpenoid) is an important marker component present in Nelumbo nucifera Gaertn. rhizome. N. nucifera rhizome has several medicinal uses including hypoglycaemic, antidiarrhoeal, antimicrobial, diuretic, antipyretic, psychopharmacological activities. To establish a simple, sensitive, reliable, rapid and validated high-performance thin-layer chromatography method for estimation of betulinic acid in hydro-alcoholic ...
He Yu - - 2010
Domoic acid (DA), a neurotoxic amino acid produced by some strains of phytoplankton, is responsible for the human toxic syndrome amnesic shellfish poisoning. This exocitotoxin results in neuronal degeneration and necrosis in specific regions of the hippocampus. Because DA accumulates mostly in shellfish, causing outbreaks in different countries, screening for ...
Chu Yung-Ming - - 2011
Silane-based methods have become the standards for the conjugation of biomolecules, especially for the preparation of one-dimensional nanomaterial biosensors. However, the specific binding of those target molecules might raise problems with regard to the sensing and non-sensing regions, which may contaminate the sensing devices and decrease their sensitivity. This paper ...
Letzel Marion - - 2010
To investigate the occurrence and fate of ritalinic acid - the main human metabolite of the psychostimulant drug methylphenidate - in the aquatic environment, a HPLC-electrospray-MS/MS method for the quantification of ritalinic acid in wastewater, surface water and bank filtrate was developed. Carbamazepine known as very stable in the aquatic ...
Ducroq D H - - 2010
WEQAS, one of the largest EQA (External Quality Assessment) providers in the UK, offers a bile acid EQA scheme, with linear serum pools containing cholic acid, deoxycholic acid and chenodeoxycholic acid, reflecting levels observed in obstructive cholestasis. Total bile acids are currently measured routinely by non-specific enzymatic methods. Traceability of ...
Li Jing-sheng - - 2010
A much "greener" and harmless leaching method for removing impurity aluminum further from industrial quartz sands by very dilute mixed acids has been presented. With the help of supersonic, the percentage of removal aluminum reached up to 52.5%/53%, that is, 17.4 ppm/17.7 ppm at 30 °C/80 °C, respectively. These results ...
Zhang Siyu - - 2010
For ecological risk assessment of the large and ever-increasing number of chemical pollutants, it is of importance to develop computational methods to screen or predict their environmental photodegradation behavior. This study developed a computational method based on the density functional theory (DFT) to predict and evaluate the photodegradation behavior and ...
Gupta Shikha - - 2010
Although a number of chemicals have been isolated from Lantana camara, only a few have been evaluated for their biological significance. As part of our drug discovery program for cytotoxic agents from Indian medicinal plants, roots of L. camara L. were chemically investigated, which resulted in the isolation and identification ...
Almeida Ana R R P - - 2010
The standard (p(0) = 0.1 MPa) molar enthalpies of formation, in the crystalline phase, of five aminomethoxybenzoic acids, at T = 298.15 K, were derived from the standard molar energies of combustion in oxygen, measured by static-bomb combustion calorimetry. Combining these results with literature results of the standard molar enthalpies ...
Griffiths M J - - 2010
Assays for total lipid content in microalgae are usually based on the Folch or the Bligh and Dyer methods of solvent extraction followed by quantification either gravimetrically or by chromatography. Direct transesterification (DT) is a method of converting saponifiable lipids in situ directly to fatty acid methyl esters which can ...
Xu Xueqin - - 2010
A simple method was established to determine protoberberine alkaloids in Cortex Phellodendri and Rhizoma Coptidis based on an acidic potassium permanganate chemiluminescence (CL) system. The optimum conditions for the CL reaction between protoberberine alkaloids and potassium permanganate were studied in detail. Under the optimum conditions, the linear response ranges for ...
Altun Deniz - - 2010
Stachyss species have been used as a medicine for centuries throughout the world. Stachys lavandulifolia Vahl. var. lavandulifolia (Lamiaceae) is of interest to researchers because the constituents such as betulinic acid, oleanolic acid, rosmarinic acid, and ursolic acid are similar to other Stachys species commonly used as an alterative in ...
Zhang Xin - - 2010
Au nanoparticles stabilized by polystyrene-co-polymethacrylic acid microspheres (PS-co-PMAA) were prepared and characterized via X-ray diffraction (XRD), and transmission electron microscope (TEM). The Au nanoparticles supported on the microspheres showed highly selective catalytic activity for homo-coupling reactions of arylboronic acids in a system of aryl-halides and arylboronic acids. X-ray photoelectron spectroscopy ...
Purcaro Giorgia - - 2010
The bacteria fatty acid profile has been extensively studied for taxonomic classification purposes, since bacteria, in general, contain particular and rare fatty acids, compared with animal and plant tissues. As for any real-world sample type, the development of rapid and reliable methods for (i) sample identification (in this case, bacterium ...
Cao Qian - - 2010
A new electrochemical sensor for melamine with 3,4-dihydroxyphenylacetic acid as the recognition element is established. The results of Fourier Transform Infrared (FT-IR) spectra demonstrate that melamine may interact with 3,4-dihydroxyphenylacetic acid to form a complex mainly through the hydrogen-bonding interaction. The electrochemical behavior of 3,4-dihydroxyphenylacetic acid in the presence of ...
Rodrigues J E A - - 2010
The organic acids present in beer provide important information on the product's quality and history, determining organoleptic properties and being useful indicators of fermentation performance. NMR spectroscopy may be used for rapid quantification of organic acids in beer and different NMR-based methodologies are hereby compared for the six main acids ...
Phillips Melissa M - - 2010
Nine organic acids (citric acid, galacturonic acid, glycolic acid, isocitric acid, malic acid, oxalic acid, quinic acid, shikimic acid, and tartaric acid) and two anions (phosphate and sulfate) were determined in a suite of Vaccinium berry-containing dietary supplement standard reference materials (SRMs). Following solvent extraction, three independent methods were utilized ...
Khiaosa-ard Ratchaneewan - - 2010
The effects of three emulsifying methods on ruminal fatty acid biohydrogenation (BH) in vitro were compared. Using a static in-vitro gas test system, four replicates of each treatment were incubated in buffered ruminal fluid. Hemicellulose (300 mg dry matter) was supplemented either with or without linoleic acid (9c12c-18:2, 5% in ...
Wang Yang - - 2010
A selective, sensitive, rapid and reliable method based on molecularly imprinted polymers (MIPs) with dual templates to determine total content of parabens in cosmetics was developed. With methylparaben (MP) and propylparaben (PP) as dual-templates, methacrylic acid (MAA) as a functional monomer and tripropylene glycol diacrylate (TPGDA) as a cross-linker, MIPs ...
Nakayama Shoji F - - 2010
Despite ongoing efforts to develop robust analytical methods for the determination of perfluorinated compounds (PFCs) such as perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) in surface water, comparatively little has been published on method performance, and the environmental distribution of these materials remains poorly described worldwide. In this study, an existing ...
Dubois M - - 2010
Okadaic acid, a diarrhetic shellfish poison, domoic acid, an amnesic shellfish poison, and saxitoxin, a paralytic shellfish poison, are three of the best-known marine biotoxins. The mouse bioassay is the method most widely used to detect many of these toxins in shellfish samples, but animal welfare concerns have prompted researchers ...
Liu Xin-Ru - - 2010
Early diagnosis and treatment for thermal injury with septic complications continue to be a serious clinical problem. In this study, plasma biomarkers of rats in the burn and/or septic models were investigated with a metabolomic method. Rat plasma samples were analyzed by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Multivariate ...
Meng Liping - - 2010
A simple, fast and sensitive liquid chromatography-electrospray tandem mass spectrometry method was established for trace levels of nine haloacetic acids (HAAs) in drinking water. Water samples were removed of residual chlorine by adding L-ascorbic acid, and directly injected after filtered by 0.22 microm membrane. Nine HAAs were separated by liquid ...
Au Catherine - - 2011
The enhancement of marks in blood on dark surfaces poses significant challenges to the forensic scientist. Current methods of enhancement include the sequential use of acid dyes (acid yellow, acid violet and acid black). Acid yellow is used to greatest effect on lighter deposits of blood on a non-porous background, ...
Dick Graham R - - 2010
A wide range of 2-pyridyl and other difficult-to-access heterocyclic N-methyliminodiacetic acid boronates can be readily prepared from the corresponding bromides via a new method involving direct transligation of 2-heterocyclic trialkoxyborate salts with N-methyliminodiacetic acid (MIDA) at elevated temperatures.
Newton Laura A A - - 2010
Homocysteine has gathered considerable interest in recent years after being implicated in the pathogenesis of various clinical conditions. It has been an elusive target with many conflicting studies casting some confusion over its significance, and much more needs to be done to ascertain its pathophysiological role--especially with respect to regimes ...
Zhao Xuebing - - 2010
Siam weed [Chromolaena odorata (L.) King & Robinson], an invasive exotic weed in China, was proposed as a feedstock for bioethanol production. This would be a promising way of using for an invasive weed that needs management and control. It was found that the glucan content of the weed stem ...
Rizza Luisa - - 2010
The aim of the present study was to compare the effectiveness and the safety of different topical agents (glycolic acid, mandelic acid, and grape juice acid mixture) in skin exfoliation by objective instrumental methods. To evaluate the exfoliating effects of these substances, a new experimental in vivo protocol based on ...
Huang Gang L - - 2010
Extraction of mannan oligosaccharides from the yeast cell wall and methods of deproteinization were studied. We extracted crude mannan oligosaccharides by the dilute alkali-Sevage method. The percentages of deproteinization and mannan oligosaccharide loss were compared as indexes using the Sevage method, trichloroacetic acid method, and hydrochloric acid method. The results ...
Gasperotti Mattia - - 2010
Accurate quantification and structural characterization of ellagitannins and ellagic acid conjugates in food, beverages, and food supplements are essential starting points for studying their effect on human health. However, accuracy is hindered both by the lack of pure standard compounds and by methods that maintain the compounds in their native ...
Franzmann Carolin - - 2010
Ergot alkaloid and ricinoleic acid contents of 63 ergot sclerotia samples from rye throughout Germany of the harvest years 2006-2009 were determined. Alkaloid contents were analyzed by means of high-performance liquid chromatography with fluorescence detection (HPLC-FLD) and ricinoleic acid contents by means of gas chromatography with flame ionization detection (GC-FID). ...
Salo Kent - - 2010
The enthalpy of sublimation has been determined for nine carboxylic acids, two cyclic (pinonic and pinic acid) and seven straight-chain dicarboxylic acids (C(4) to C(10)). The enthalpy of sublimation was determined from volatility measurements of nano aerosol particles using a volatility tandem differential mobility analyzer (VTDMA) set-up. Compared to the ...
Mallakpour Shadpour - - 2010
This is the first description of the application of molten tetrabutylammonium bromide (TBAB) in the presence of triphenyl phosphite (TPP) for the synthesis of novel polyamides (PAs). Monomer diacid, 5-[(9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)-3-methylbutanoylamino]isophthalic acid (4), having anthracenic and amino acid S-valine pendant group, was synthesized in four steps. Several novel, optically active PAs ...
Lowenthal Mark S - - 2010
An isotope-dilution liquid chromatography-tandem mass spectrometry (ID LC-MS/MS) measurement procedure was developed to accurately quantify amino acid concentrations in National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 2389a-amino acids in 0.1 mol/L hydrochloric acid. Seventeen amino acids were quantified using selected reaction monitoring on a triple quadrupole ...
Kucklick John R - - 2010
The National Institute of Standards and Technology (NIST) has a diverse collection of control materials derived from marine mammal blubber, fat, and serum. Standard Reference Material (SRM) 1945 Organics in Whale Blubber was recertified for polychlorinated biphenyl (PCB) congeners, organochlorine pesticides, and polybrominated diphenyl ether (PBDE) congeners. SRM 1945 has ...
Liu Yan - - 2010
A novel colorimetric luminescence sensor strip for the detection of indole-3-acetic acid (IAA) has been fabricated by using green emissive quantum dots of cadmium telluride (CdTe QDs) as a background layer and a red emissive europium chelate, [4'-(9-anthryl)-2,2':6',2''-terpyridine-6,6''-diyl]bis(methylenenitrilo) tetrakis(acetate)-Eu(3+) (ATTA-Eu(3+)), as a specific sensing layer coated on the surface of ...
Ben Rejeb Ines - - 2010
A new, simple, and original method is described for specific measurement of polyunsaturated fatty acid content in olive oil. This analytical system uses coupled enzymes, lipase and lipoxygenase. The system consists of lipase-catalyzed hydrolysis of triacylglycerol and subsequent lipoxygenation of liberated polyunsaturated fatty acids. The hydroperoxy-fatty acids formed were easily ...
Reenil? Ilkka - - 2010
Novel HPLC method utilizing UV-detection was developed to analyse catechol-O-methyltransferase (COMT) products, vanillic acid and isovanillic acid, S-adenosylhomocysteine (SAH) and adenosine formed from dihydroxybenzoic acid and S-adenosyl-L-methionine (SAM) by incubation of the rat tissues. Entacapone, a COMT inhibitor, prevented the formation of SAH only partially in the striatal homogenate whereas ...
Zhao Shulin S Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education), College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin, 541004, - - 2010
Since the channels in micro- and nanofluidic devices are extremely small, a sensitive detection is required following microchip electrophoresis (MCE). This work describes a highly sensitive and yet universal detection scheme based on chemiluminescence resonance energy transfer (CRET) for MCE. It was found that an efficient CRET occurred between a ...
Caligiani Augusta - - 2010
1H NMR spectra were recorded of methanolic extracts of seven soybean varieties (Glycine max.), cultivated using traditional and organic farming techniques. It was possible to identify signals belonging to the groups of amino acids, carbohydrates, organic acids and aromatic substances in the spectra. In the aromatic zone, the isoflavone signals ...
Kang Gumin - - 2010
Mixed hydrofluoric and nitric acids are widely used as a good etchant for the pickling process of stainless steels. The cost reduction and the procedure optimization in the manufacturing process can be facilitated by optically detecting the concentration of the mixed acids. In this work, we developed a novel method ...
Liao Xiangjun - - 2010
An analytical method has been developed for the measurements of five urinary acids namely, quinolinic acid, picolinic acid, nicotinic acid, 2-pyridylacetic acid and 3-pyridylacetic acid. The high performance liquid chromatograph-electrospray ionization mass spectrometry was operated in positive polarity under selected ion monitoring mode, with a column flow rate of 0.2 ...
Huang Haowen - - 2010
In this paper, we have developed a simple, rapid, selective, and ultra-sensitive assay to detect cysteine by means of gold nanorods assembly. This methodology is based on the end-to-end assembly of gold nanorods and it is very sensitive due to the useful formation of the gold nanorods chain in the ...
Brand?n S A - - 2010
Theoretical calculations on the molecular geometry and the vibrational spectrum of 4-hydroxybenzoic acid were carried out by the Density Functional Theory (DFT/B3LYP) method. In addition, IR and Raman spectra of the 4-hydroxybenzoic acid in solid phase were newly recorded using them in conjunction the experimental and theoretical data (including SQM ...
Meng Qing H - - 2010
BACKGROUND: There have been an increasing number of reports on false increase of lactate in ethylene glycol poisoning. We recently encountered two cases of ethylene glycol poisoning with very high blood lactate concentrations on ABL blood gas analyzers. METHODS: Patient plasma lactate concentrations were measured on different chemistry instruments in ...
Nakano Shigenori - - 2010
A novel flow-injection spectrophotometry has been developed for the determination of molybdenum(VI) at nanograms per milliliter levels. The method is based on the catalytic effect of molybdenum(VI) on the bromate oxidative coupling of p-hydrazinobenzenesulfonic acid with N-(1-naphthyl)ethylenediamine to form an azo dye (lambda(max)=530nm). Chromotropic acid (4,5-dihydroxy-2,7-naphthalenedisulfonic acid) acted as an ...
Bednar A J - - 2010
Interest in tungsten occurrence and geochemistry is increasing due to increased use of tungsten compounds and its unknown biochemical effects. Tungsten has a complex geochemistry, existing in most environmental matrices as the soluble and mobile tungstate anion, as well as poly- and heteropolytungstates. Because the geochemistry of tungsten is substantially ...
Issa Y M - - 2010
Two simple and highly sensitive spectrophotometric methods were developed for the quantitative determination of the drug sildenafil citrate (SC), Viagra, in pure form and in pharmaceutical formulations, through ion-associate formation reactions (method A) with mono-chromotropic acid azo dyes, chromotrope 2B (I) and chromotrope 2R (II) and ion-pair reactions (method B) ...
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