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41.
Buckwheat is a pseudocereal that has gained increasing interest of industry and consumers over the past decade. Little, however, is known about its dietary fiber composition and nonstarch polysaccharide structures. Analysis of the monosaccharide composition indicated large amounts of pectic polysaccharides in both insoluble and soluble fiber from buckwheat. Methylation analysis gave further insights into the structures of the polysaccharides. The corresponding partially methylated alditol acetates suggested only low amounts of galactans. Xyloglucans were the main hemicellulosic polysaccharides in the insoluble fiber fraction. Highly branched arabinans, exclusively substituted at position O3, were of higher abundance. These results were confirmed by screening endo‐arabinanase and endo‐galactanase liberated oligosaccharides with high‐performance anion‐exchange chromatography with pulsed amperometric detection and LC‐MS2. Application of this method also demonstrated highly branched arabinan areas within the pectic polysaccharides. Only low amounts of fiber associated hydroxycinnamic acids and diferulic acids were liberated by alkaline treatment, and no evidence was found for their attachment to polysaccharides, suggesting only a minor impact of these structural elements on fiber structures in dehulled buckwheat seeds.  相似文献   
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This study investigated the association between presence of respiratory pathogens and development of Canine Infectious Respiratory Disease Complex (CIRDC) in dogs in 5 Canadian small animal clinics. In total, 86 dogs were tested using a commercial PCR respiratory panel; 64 dogs were considered as cases and 22 were control dogs matched by veterinary clinic. No control animals (0/22) were positive for canine parainfluenza virus (CPIV), whereas 27/64 (42%) CIRDC cases were positive. Furthermore, 81% of case dogs tested positive for Mycoplasma cynos, compared with 73% of control dogs. Canine respiratory corona virus (CRCoV) was detected in no control dogs compared with 9.4% of clinical dogs. No animals were positive for any influenza virus type A present in the diagnostic panel. Presence of CPIV was associated (P < 0.01) with the occurrence of CIRDC after adjustment for demographic factors and presence of CRCoV (P = 0.09).  相似文献   
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OBJECTIVE: To determine the feasibility of the use of Fourier-transform infrared (FTIR) spectroscopy within the midinfrared range to differentiate synovial fluid samples of joints with osteochondrosis from those of control samples. ANIMALS: 33 horses with osteochondrosis of the tarsocrural joint and 31 horses free of tarsocrural joint disease. PROCEDURES: FTIR spectroscopy of synovial fluid was used. Sixty-four synovial fluid samples from the tarsocrural joint were collected. Of these, 33 samples were from horses with radiographic evidence of osteochondrosis of the tarsocrural joint and 31 from control joints. Disease-associated features within infrared spectra of synovial fluid were statistically selected for spectral classification, and the variables identified were used in a classification model. Linear discriminant analysis and leave-one-out cross-validation were used to develop a classifier to identify joints with osteochondrosis. RESULTS: 12 significant subregions were identified that met the selection criteria. The stepwise discriminant procedure resulted in the final selection of 6 optimal regions that most contributed to the discriminatory power of the classification algorithm. Infrared spectra derived from synovial fluid of joints with osteochondrosis were differentiated from the control samples with accuracy of 77% (81% specificity and 73% sensitivity). CONCLUSIONS AND CLINICAL RELEVANCE: The disease-associated characteristics of infrared spectra of synovial fluid from joints with osteochondrosis may be exploited via appropriate feature selection and classification algorithms to differentiate joints with osteochondrosis from those of control joints. Further study with larger sample size including age-, breed-, and sex-matched control horses would further validate the clinical value of infrared spectroscopy for the diagnosis of osteochondrosis in horses.  相似文献   
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May M  Kleven SH  Brown DR 《Avian diseases》2007,51(4):829-833
Eleven strains of the avian pathogen Mycoplasma synoviae were evaluated for the presence of sialidase activity with the use of the fluorogenic substrate 2'-(4-methylumbelliferyl)-alpha-D-N-acetylneuraminic acid and the sialidase inhibitor 2-deoxy-2,3- didehydro-N-acetylneuraminic acid. The kinetics of in vitro growth in modified Frey medium were also assessed for each strain. Five strains had been isolated from clinically symptomatic chickens, and strains WVU 1853T and K3344 have been demonstrated to be capable of reproducing disease in specific-pathogen-free chickens. All strains exhibited sialidase activity, although the amount varied 65-fold among strains (P < 0.0001) from 1.3 x 10(-7) to 2.0 x 10(-9) activity units per colony-forming unit. Strains originally isolated from clinically symptomatic birds had more (P < 0.05) sialidase activity than strains from asymptomatic birds. Strain WVU1853T exhibited the most sialidase activity (P < 0.0001) and grew to the highest culture density (P < 0.0001) among strains, but across strains, the rank correlation of growth rate with sialidase activity was not significant. Negligible activity was detected in conditioned culture supernatant fluid. This is the first report of sialidase activity in pathogenic strains of M. synoviae, which suggests a potential enzymatic basis for virulence of the organism.  相似文献   
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