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101.
Tepoxalin is a non-steroidal anti-inflammatory drug with analgesic, anti-inflammatory, and antipyretic properties and has been recently introduced into veterinary medicine. The aim of this study was to evaluate the pharmacokinetic/pharmacodynamic (PK/PD) profile of tepoxalin to assess whether it would be suitable for clinical use in horses. Six female fasting/fed horses were given 10mg/kg tepoxalin orally in a cross-over study. After administration, tepoxalin underwent rapid and extensive hydrolytic conversion to its carboxylic acid metabolite RWJ-20142. In animals that had been fed, the plasma concentrations of tepoxalin were undetectable, whereas in fasting animals they were close to the limit of quantification of the method. No differences between the fasting/fed groups in RWJ-20142 plasma concentrations were shown. Tepoxalin showed a strong and long-lasting ex vivo inhibitory activity against cyclooxygenase (COX)-1, mainly due to its main metabolite RWJ-20142. Tepoxalin and RWJ-20142 do not seem to possess either COX-2 or 5-lipoxygenase inhibitory activity in the horse. These features suggest that the drug is a selective COX-1 inhibitor in horses, with no significant anti-inflammatory activity. Thus, its long term use in equine practice could be of concern.  相似文献   
102.
Large and small piroplasms have been observed in the blood smears of various wild carnivores, but few studies utilizing molecular characterization have been done. The goal of this present study was to investigate the presence of Babesia sp. by molecular and serologic techniques in exotic and neotropical carnivores maintained in captivity at Brazilian zoos. Blood and sera samples were collected from 146 Brazilian wild felids, 21 exotic felids, 1 genet (Genetta tigrina), 3 European wolves (Canis lupus), and 94 Brazilian wild canids in Brazilian zoos in the S?o Paulo and Mato Grosso states and in the Federal District. A total of 53 wild felids (31.74%) and 10 wild canids (10.31%) were seropositive for Babesia canis by Indirect Fluorescent Antibody Test (IFAT). Antibodies were detected in ocelots, little-spotted cats, margays, pampas cats, jaguars, pumas, jaguarundis, crab-eating foxes, and bush dogs. Babesia sp. DNA, with high similarity to B. leo, was detected in one pampas cat and one genet.  相似文献   
103.
Total aliphatic and indole glucosinolates, phenolic compounds (flavonoids and hydroxycinnamoyl derivatives), and vitamin C contents were evaluated in freshly harvested broccoli (Brassica oleracea L., var. italica, cv. Marathon) inflorescences. These were film-wrapped and stored for 7 days at 1 degrees C to simulate a maximum period of commercial transport and distribution. After cold storage, inflorescences were kept for 3 days at 15 degrees C to simulate a retail sale period. For wrapping, low-density polyethylene (LDPE) of 11 microm thickness was used. Gas composition was about 17% O(2) and 2% CO(2) during cold storage and about 16% O(2) and 3-4% CO(2) during shelf life within packages. The predominant glucosinolates were 4-methylsulfinylbutyl-glucosinolate (glucoraphanin), 3-indolylmethyl-glucosinolate (glucobrassicin), and 1-methoxy-3-indolylmethyl-glucosinolate (neoglucobrassicin). The predominant hydroxycinnamoyl derivatives were identified as 1,2,2'-trisinapoylgentiobiose, 1,2-diferuloylgentiobiose, 1,2'-disinapoyl-2-feruloylgentiobiose, and 3-O-caffeoyl-quinic (neochlorogenic acid). Results showed major losses at the end of both periods, in comparison with broccoli at harvest. Thus, the respective losses, at the end of cold storage and retail periods, were 71-80% of total glucosinolates, 62-59% of total flavonoids, 51-44% of sinapic acid derivatives, and 73-74% caffeoyl-quinic acid derivatives. Slight differences in all compound concentrations between storage and retail sale periods were detected. Distribution and retail periods had minimal effects on vitamin C. Weight loss was monitored at the end of both periods.  相似文献   
104.
The antiradical activity of water-soluble components contained in mushrooms (Psalliota campestris), onions (Allium cepa), white cabbage (Brassica oleracea var. alba), and yellow bell peppers (Capsicum annuum) against hydroxyl radicals was tested in a chemical and biological system. The vegetable juices were obtained by centrifugation of a vegetable homogenate processed at 2 degrees C or heated at 102 degrees C. The chemical system consisted of a buffered reaction mixture composed of Fe(III)-EDTA, 2-deoxy-D-ribose, ascorbic acid, and H(2)O(2) generating the hydroxyl radical. The antiradical activity was expressed as an inhibition of deoxyribose degradation. The biological system consisted of IMR32 neuroblastoma cells exposed to H(2)O(2) in the presence or absence of the vegetable juices. Cells were pretreated for either 24 h or 1 h with the vegetable juices, and reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was used as a cell viability assay. All vegetable juices inhibited the degradation of deoxyribose and increased the viability of H(2)O(2) treated cells. Raw mushroom juice proved to be the most active in both cases. Boiling significantly affected the activity of mushroom juice, but did not change significantly the effect on onions and yellow bell peppers, and partially increased the activity of white cabbage juice. Mushroom antiradical activity was also confirmed by a cytofluorimetric analysis.  相似文献   
105.
Improvement of a previously described method of purification of alpha-galactosides, members of the raffinose family of oligosaccharides (RFOs), has been developed for lupins. The considerable amount of sucrose present in the RFO preparations obtained by the previous method has been removed by modifying the purification stage on diatomaceous earth and charcoal. The present method allows for the preparation of high-purity RFOs containing approximately 99.4% of RFOs in the form of a white fine powder, which provides new perspectives for the production of pure alpha-galactoside preparations for their use as prebiotics in functional foods.  相似文献   
106.
A rapid liquid chromatography electrospray ionization tandem mass spectrometry with negative ion detection method was developed and validated to determine cocoa flavonoid metabolites in human plasma and urine after the intake of a standard portion of a cocoa beverage. A chromatographic run time of only 9 min provided clear separation of all metabolites and internal standards. Samples were analyzed in a product-ion scan of m/z 289, 369, and 465 to identify the metabolites and in multiple reaction monitoring acquisition mode to quantify (-)-epicatechin ((-)-Ec) (289/ 245), (-)-epicatechin-glucuronide ((-)-EcG) (465/289), and (-)-epicatechin-sulfate ((-)-EcS) (369/289). One (-)-Ec-G and three (-)-Ec-S were identified and confirmed in urine as the major metabolites, and one (-)-Ec-G was the only metabolite present in plasma volunteers (n = 5) at a mean concentration of 625.7 +/- 198.3 nmol/L at 2 h after consumption of a cocoa beverage containing 54.4 mg of (-)-Ec.  相似文献   
107.
A three-dimensional (3D) off-line chemical transport model (CTM) has been used to study an Arctic ozone minihole event in early December 2002, when the meteorological conditon were severely colder than in recent years. The minimum temperatures were below 188 K on 6 December 2002 and remained below 195 K for the entire month. Such temperatures are low enough for the formation of PSCs (polar stratospheric clouds) which were observed by a visible/near infrared solar occultation instrument by the Polar Ozone and Aerosol Measurement (POAM) III experiment. The SLIMCAT model compares well with the depth and evolution of the ozone distribution as observed by the second European Remote Sensing Satellite (ERS-2) Global Ozone Monitoring Experiment (GOME). The combined effect of a very strong and large intrusion of sub-tropical air, and uplifting of air masses of low ozone concentrations from the troposphere plays important role in the fomation of the ozone minihole. The modelled chemical ozone loss rate was relatively fast in the lower stratosphere in the region of frequent PSCs and higher levels of ClO and BrO. The observed PSCs in the vicinity of the minihole supports the model-predicted location of PSCs and chlorine activation. However, ozone miniholes have been attributed almost entirely to dynamical effects due to its short duration.  相似文献   
108.
In this work the formation and composition of aggregates between metals and organic material is studied in real fog samples. In a preliminary experiment it has been found that concentrated cloud samples form a yellow-brown precipitate in the presence of Fe(III). Standards of humic acids and fulvic acids co-precipitate with Fe(III), forming similar aggregates i.e. iron-humates (Fe-HA) and iron-fulvates (Fe-FA). By comparing the solubility properties of aggregates by extracting organic carbon (OC) in different pH conditions, it has been observed that fog droplet particulate samples are characterised by solubility properties more similar to those of Fe-HA than Fe-FA. Dilute alkaline solutions can also easily extract organic refractory substances that form aggregates with metals. The recoveries of the total extractable organic matter (accounting for 12% of total insoluble carbon and 15% of particulate mass) are similar to those of humic-like substances (HULIS) from particulate samples. The chromatographic behaviour and functional group characteristics measured in the alkali-extract fraction of precipitated aggregates with iron and in the insoluble particulate of fog samples, are those of humic-like material. Thus, soluble HULIS are able to interact with iron to form particulate, but the composition of a large fraction of insoluble organic carbon is still unknown. These findings have implications on the solubility and surface tension properties of fog droplets and can therefore potentially influence droplet formation, as well as cloud chemical and photochemical processes.  相似文献   
109.
Even when plant growth was not visibly affected, ammonium versus nitrate nutrition had distinct effects on some parts of plant metabolism. Barley seedlings growing on 3 mM ammonium rapidly accumulated ammonium up to 20 mM in the roots. In leaves, ammonium accumulation was observed only when the pH of the nutrient medium was very low (pH 4). Yet even under the most extreme conditions there was no indication that plants were suffering from uncoupling of ATP synthesis or from a lack of carbohydrates. Especially dramatic was the response of the organic acid content of pea and barley leaves: it decreased strongly within a few days upon transfer of plants from nitrate to ammonium-media, and this was apparently not due to an inhibition of PEPcarboxylase, which was rather activated under ammonium nutrition. As malate dispappeared from leaves even when pea plants were transferred to an N-free medium, malate degradation was not necessarily connected to increased amino acid synthesis, but eventually to a more rapid decarboxylation by malic enzyme. Also, malate degradation was not a response to ammonium, but rather to (the absence of) nitrate.  相似文献   
110.
Traffic activities generate a wide gradation of anthropogenic particulate matter that is entrained in highway snow and snowmelt. Granulometric-based analyses of this particulate mattercan provide guidance for selection and design for snowmelt solid/liquid separation processes. This study presents a granulometry-based analysis of snow melt particles from 10 highway shoulder sites in urban Cincinnati (State of Ohio, U.S.A.) generated from a 46 cm, 48 hr snowfall with a highwayshoulder residence time of 102 hr. Each site was exposed totraffic and maintenance activities (plowing and de-icing saltsonly). Despite variations in gradations and particle indices, measured l nv-N t (number-volume mean size-particle counts) values for all sites were closely modeled using a two-parameter power law model. The model exponent, β, ranged from 2.22 to 2.64 indicating that a significant fractionof surface area is associated with the coarser gradation of particles. Modeled results support previous experimental data indicating the predominance of surface area and heavy metal mass is associatedwith the coarser fraction of particles. Results indicated a statistically significant difference in densities for coarse (2.86 gm cm-3) and fine particles (2.75 gm cm-3) (P < 10-11).A methodology is presented in the form of a process selection diagram to evaluate mechanisms of particle separation. It was determined that sedimentation could remove 90% of particles, bymass, within 2 hr for a typical roadway drainage design. The influence of particle specific gravity on sedimentation efficiency is illustrated for a range of specific gravities from 1.1 to 4.0. Although the very high concentrations of particulate matter in highway snow melt do not make it amenableto straining or direct filtration, such processes may be feasible as a secondary treatment for snowmelt or storm water effluent discharges to receiving waters.  相似文献   
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