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51.
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Pyometra was recorded in five camels and Actinomyces pyogenes (Corynebacterium pyogenes) was isolated from pus of the affected camels. 相似文献
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Our objectives were to test the potential replacement of fish meal by soy protein concentrate (SPC) in high-energy, extruded diets fed to rainbow trout (Oncorhynchus mykiss) and to evaluate the efficiency of DL-methionine supplementation of soy-based diets. Groups of trout (initial BW 103 to 106 g) were fed to visual satiety with isonitrogenous (6.6% DM) high-energy (22.8 MJ/kg DM gross energy), extruded diets, in which fish meal was progressively replaced with SPC (0, 50, 75, and 100%). Three 100% SPC diets were formulated to be either unsupplemented or supplemented with DL-methionine, so that total methionine content was .8 or 1.0% of DM. The quality of the SPC source used was assessed by measuring the antitryptic and antigenic activities and the concentrations of the isoflavones daidzein and genistein. Apparent digestibility of the diets was determined using the indirect method. A growth trial was conducted over 90 d at a water temperature of 18 degrees C. In addition to body composition analysis, plasma amino acid concentrations, anti-soy protein antibodies in the serum, and isoflavone concentrations in the bile were measured. The SPC source tested exhibited low antitryptic and antigenic activities, but it contained high concentrations of isoflavones (1,990 and 5,903 ppm for daidzein and genistein, respectively). Protein digestibility was high (92%) and was unaffected either the proportion of SPC in the diet or by DL-methionine supplementation. This was also true for the availability of amino acids, except phenylalanine. Digestibility of lipid and energy was reduced by 19% when SPC totally replaced fish meal. Growth rate was reduced when more than 50% of the dietary protein was of soy origin (daily growth coefficient of 3.2 and 2.1% for the control and the unsupplemented 100% SPC diet, respectively). The effect on growth was mainly explained by a general decline in feed intake (13.7 and 12.0 g DM x kg BW(-1) x d(-1) for the control and the unsupplemented 100% SPC diet, respectively) and in lipid and, thus, in energy digestibility. The DL-methionine supplementation partially reversed the depressive effects of high dietary SPC incorporation (+13% growth), mainly by enhancing intake. The negative effect of SPC incorporation either may be due to the high isoflavone concentration or to an interaction between the soy protein component and the dietary lipids. 相似文献
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Podsiadlo P Kaushik AK Arruda EM Waas AM Shim BS Xu J Nandivada H Pumplin BG Lahann J Ramamoorthy A Kotov NA 《Science (New York, N.Y.)》2007,318(5847):80-83
Nanoscale building blocks are individually exceptionally strong because they are close to ideal, defect-free materials. It is, however, difficult to retain the ideal properties in macroscale composites. Bottom-up assembly of a clay/polymer nanocomposite allowed for the preparation of a homogeneous, optically transparent material with planar orientation of the alumosilicate nanosheets. The stiffness and tensile strength of these multilayer composites are one order of magnitude greater than those of analogous nanocomposites at a processing temperature that is much lower than those of ceramic or polymer materials with similar characteristics. A high level of ordering of the nanoscale building blocks, combined with dense covalent and hydrogen bonding and stiffening of the polymer chains, leads to highly effective load transfer between nanosheets and the polymer. 相似文献
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Utture SC Banerjee K Dasgupta S Patil SH Jadhav MR Wagh SS Kolekar SS Anuse MA Adsule PG 《Journal of agricultural and food chemistry》2011,59(14):7866-7873
The dissipation behavior and degradation kinetics of azoxystrobin, carbendazim, and difenoconazole in pomegranate are reported. Twenty fruits/hectare (5 kg) were collected at random, ensuring sample-to-sample relative standard deviation (RSD) within 20-25%. Each fruit was cut into eight equal portions, and two diagonal pieces per fruit were drawn and combined to constitute the laboratory sample, resulting in RSDs <6% (n = 6). Crushed sample (15 g) was extracted with 10 mL of ethyl acetate (+ 10 g Na(2)SO(4)), cleaned by dispersive solid phase extraction on primary secondary amine (25 mg) and C(18) (25 mg), and measured by liquid chromatography tandem mass spectrometry. The limit of quantification was ≤0.0025 μg g(-1) for all the three fungicides, with calibration linearity in the concentration range of 0.001-0.025 μg mL(-1) (r(2) ≥ 0.999). The recoveries of each chemical were 75-110% at 0.0025, 0.005, and 0.010 μg g(-1) with intralaboratory Horwitz ratio <0.32 at 0.0025 μg g(-1). Variable matrix effects were recorded in different fruit parts viz rind, albedo, membrane, and arils, which could be correlated to their biochemical constituents as evidenced from accurate mass measurements on a Q-ToF LC-MS. The residues of carbendazim and difenoconazole were confined within the outer rind of pomegranate; however, azoxystrobin penetrated into the inner fruit parts. The dissipation of azoxystrobin, carbendazim, and difenoconazole followed first + first order kinetics at both standard and double doses, with preharvest intervals being 9, 60, and 26 days at standard dose. At double dose, the preharvest intervals extended to 20.5, 100, and 60 days, respectively. 相似文献
59.
Zhang K Wong JW Yang P Tech K Dibenedetto AL Lee NS Hayward DG Makovi CM Krynitsky AJ Banerjee K Jao L Dasgupta S Smoker MS Simonds R Schreiber A 《Journal of agricultural and food chemistry》2011,59(14):7636-7646
A multiresidue method analyzing 209 pesticides in 24 agricultural commodities has been developed and validated using the original Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) procedure and high performance liquid chromatography-positive electrospray ionization-tandem mass spectrometry (LC-MS/MS) analysis. Using solvent-only calibration standards (SOCSs) and matrix-matched calibration standards (MMCSs), it was demonstrated that a minimal concentration of 5-10 μg/kg (part per billion, ppb) of analytes in matrix is required for the consistent identification of targeted pesticides with two MRM transitions. Method performance was validated by the precision and accuracy results obtained from fortification studies at 10, 25, 100, and 500 ppb and MMCSs. The method was demonstrated to achieve an average recovery of 100 ± 20% (n = 4) for >75% of evaluated pesticides at the low fortification level (10 ppb) and improved to >84% at the higher fortification concentrations in all 24 matrices. Matrix effects in LC-MS/MS analysis were studied by evaluating the slope ratios of calibration curves (1.0-100 ng/mL) obtained from the SOCSs and MMCSs. Principal component analysis (PCA) of LC-MS/MS and method validation data confirmed that each matrix exerts its specific effect during the sample preparation and LC-MS/MS analysis. The matrix effect is primarily dependent on the matrix type, pesticide type and concentration. Some caution is warranted when using matrix matched calibration curves for the quantitation of pesticides to alleviate concerns on matrix effects. The QuEChERS method with LC-MS/MS was used to identify and quantitate pesticides residues, with concentrations ranging from 2.5 to >1000 ppb in a variety of agricultural samples, demonstrating fitness for screening and surveillance applications. 相似文献
60.
C. Blin S. Panserat F. Médale E. Gomes J. Brèque S. Kaushik R. Krishnamoorthy 《Fish physiology and biochemistry》1999,21(2):93-102
The efficiency of enzymatic conversion of glucose into glucose-6-phosphate in fish fed carbohydrates is still a matter of debate. This study reports the first ever identification of hexokinase-family members at a molecular level in fish. The deduced amino acid sequences of six cDNA clones allowed their assignement either to hexokinase IV (glucokinase) for rainbow trout (Oncorhynchus mykiss), common carp (Cyprinus carpio) and gilthead seabream (Sparus aurata) or to hexokinase I/II for the common carp (two clones) and the gilthead seabream, based on their similarities to known members of the HK family. The evolutionary relationships among these sequences were investigated by phylogenetic analysis. These hexokinase sequences constitute potential molecular tools for analysis of interspecific differences in dietary carbohydrate utilization in fish. 相似文献