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91.
As indicators of the early stage of the Maillard reaction in carrots, N-(furoylmethyl) amino acids (FMAAs) formed during acid hydrolysis of the corresponding Amadori products were analyzed using RP-HPLC with UV detection. N(ε)-FM-Lys (furosine), FM-Gly, FM-Ala, FM-Val, FM-Ile, FM-Leu, and FM-GABA were identified using synthesized standard material by means of mass spectrometry. Furthermore, N(ε)-carboxymethyllysine (CML) and pyrraline were analyzed as indicators for advanced stages of glycation. For commercial samples with high water content, the formation of Amadori compounds predominates, whereas the advanced stage of Maillard reaction plays only a minor part. Carrot juices, baby food, and tinned carrots showed quite low rates of amino acid modification up to 5%. For dehydrated carrots, significantly higher values for Amadori products were measured, corresponding to a lysine derivatization of up to 58% and nearly 100% derivatization of GABA. Drying experiments revealed great differences in reactivity between the amino acids studied. Whereas furosine reached constant values quite quickly, some FMAAs showed a continuous increase with heating time, indicating that selected FMAAs can be used as a hallmark for the early Maillard reaction to control processing conditions. 相似文献
92.
Ndung'u MW Kaoneka B Hassanali A Lwande W Hooper AM Tayman F Zerbe O Torto B 《Journal of agricultural and food chemistry》2004,52(16):5027-5031
The crude methanol extracts of the root barks of Turraea wakefieldii and Turraea floribunda were found to show mosquito larvicidal activity against third-instar larvae of Anopheles gambiae sensu stricto. Four new limonoids comprising a vilasininoid 1 and three havanensinoids 2-4 were isolated from the chloroform fractions of the methanol extracts of T. wakefieldii and T. floribunda, respectively. The structures of the compounds were elucidated by NMR spectroscopy. Compounds 1, 2, and 4 had LD50 values of 7.1, 4.0, and 3.6 ppm, respectively, and were more potent than azadirachtin, which had an LD50 value of 57.1 ppm when tested against larvae of A. gambiae. 相似文献
93.
Antioxidant properties of bran extracts from "Akron" wheat grown at different locations 总被引:3,自引:0,他引:3
Yu L Perret J Harris M Wilson J Haley S 《Journal of agricultural and food chemistry》2003,51(6):1566-1570
Bran extracts of Akron wheat grown at four nonirrigated and one irrigated testing locations were examined and compared for their free radical scavenging properties against the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*)) and the radical cation ABTS(*)(+), chelating capacities, and total phenolic content (TPC) to determine the potential effects of environmental factors on the antioxidant properties of hard winter wheat. The environmental factors included total solar radiation, average daily solar radiation, and number of hours exceeding 32 degrees C. The results showed that bran samples from different growing locations may significantly differ in their radical scavenging activities against both DPPH(*) and ABTS(*)(+), chelating capacities, and TPC. A significant negative correlation was detected between the chelating activities of the bran samples from the four nonirrigated locations and total solar or daily average solar radiation (r = -0.999 and P = 0.001). These data suggest potential influences of growing conditions on the antioxidant properties of hard winter wheat and the possibility of producing wheat that is strong in a selected antioxidant property by optimizing the growing conditions of a selected wheat variety. More research is required to further investigate the relationship among antioxidant properties and environmental factors using different wheat varieties and larger sample sizes. 相似文献
94.
Anne Jackson 《Australian veterinary journal》2009,87(6):211-212
Bandaging and second intention healing in distal limbs of horses ▪ Auricular chondrosis in a horse ▪ National survey of antimicrobials in the Australian pig industry ▪ Analgesia for knife and ring castration in lambs ▪ Incidence of lymphoma in a colony of baboons ▪ Viruses in black tiger prawns from Weipa ▪ Sacral osteochondrosis in German Shepherd Dogs ▪ Congenital pyloric obstruction from a gastric hyperplastic polyp 相似文献
95.
Nicole I. Stacy Mary B. Nabity Nicole Hackendahl Melanie Buote Jennifer Ward Pamela E. Ginn William Vernau William L. Clapp John W. Harvey 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(1):113-120
Abstract: Two young adult dogs with gastrointestinal signs were each found to have an intra‐abdominal mass based on physical examination and diagnostic imaging. On exploratory laparotomy, small intestinal masses and mesenteric lymphadenopathy were found in both dogs; a liver mass was also found in dog 1. Cytologic and histologic examination of intestinal and liver masses and mesenteric lymph nodes revealed 2 distinct lymphoid cell populations: lymphoblasts and atypical Mott cells. With Romanowsky stains, the atypical Mott cells contained many discrete, clear to pale blue cytoplasmic inclusions consistent with Russell bodies that were positive by immunohistochemistry for IgM and CD79a in both dogs and for IgG in dog 2. The Mott cells and occasional lymphoblasts stained strongly positive with periodic acid‐Schiff. Using flow cytometric immunophenotyping in dog 1, 60% of peripheral blood mononuclear cells and 85% of cells in an affected lymph node were positive for CD21, CD79a, IgM, and MCH II, indicative of B‐cells. With electron microscopy, disorganized and dilated endoplasmic reticulum was seen in Mott cells in tumors from both dogs. Antigen receptor gene rearrangement analysis of lymph node and intestinal masses indicated a clonal B‐cell population. Based on cell morphology, tissue involvement, and evidence for clonal B‐cell proliferation, we diagnosed neoplasms involving Mott cells. To the authors' knowledge, this is the second report of Mott cell tumors or, more appropriately, B‐cell lymphoma with Mott cell differentiation, in dogs. More complete characterization of this neoplasm requires further investigation of additional cases. This lymphoproliferative disease should be considered as a differential diagnosis for canine gastrointestinal tumors. 相似文献
96.
Tracy Miesner David Wilkie† Anne Gemensky-Metzler‡ Steven Weisbrode§ Carmen Colitz¶ 《Veterinary ophthalmology》2009,12(4):263-268
At The Ohio State University from 1994–2006 six of seven horses evaluated for primary orbital disease were diagnosed with extra-adrenal paraganglioma (EAPG). The horses ranged in age from 14 to 24 years, with a mean of 16.8 years. Duration of clinical signs was 1.5 years to 5 years, with a mean of 2.8 years. Clinical signs varied, but all six had non-painful exophthalmus of the right eye. Five horses had complete ocular exams reported; three of five had decreased to absent vision, two of five had pale optic nerves, and in three of five, difficulty of retropulsion of the globe was noted. Diagnostic tests performed included complete blood count, serum profile, radiography, ultrasound, computed tomography, true-cut biopsy, ocular examination, guttural pouch endoscopy, oral examination, and physical examination. Expulsive hemorrhage during orbital exenteration occurred in all horses. In five of six cases, tumor extension through the orbital foramen was apparent intra-operatively. Histopathologic appearance of all surgically removed tissues consisted of sheets of polygonal cells with abundant lightly granular cytoplasm, round nuclei with vesicular chromatin, and rare mitoses. Neoplastic cells were arranged into small groups separated by a fine fibrovascular stroma. All six cases were chromagranin positive on immunohistochemical staining. Follow-up ranged from six months to six years, with a mean of two years. Four of the five horses that recovered from surgery had no apparent tumor recurrence in 6–48 months. 相似文献
97.
Amber L. Labelle Ralph E. Hamor Anne M. Barger Carol W. Maddox† Carrie B. Breaux 《Veterinary ophthalmology》2009,12(1):48-52
An 8-year-old male castrated Domestic Short-haired cat was examined for a 1-week history of blepharospasm and mucoid ocular discharge OS. Examination revealed ulcerative keratitis with stromal loss, stromal infiltrate, corneal edema, perilimbal vascularization and miosis. Cytology of the cornea revealed multiple dichotomously branching, septate fungal hyphae and severe, predominantly neutrophilic inflammation. PCR of the cytology samples confirmed the presence of Aspergillus flavus while fungal and bacterial cultures were negative. Treatment with topical 1% voriconazole solution was successful in resolving the keratomycosis. 相似文献
98.
The aim of this study was to investigate to what extent different occupational devices (pendular beam, cross of chains or lifting beam) offered simultaneously were used by one or more pigs kept in pens with or without straw during the fattening period. The data were obtained in four fattening periods. In every round four pens with nine animals each were available, two of them had a solid concrete floor and were littered with straw the other two had a partially slatted floor without any straw. At three stages during each fattening period the behaviour of the pigs was video-recorded for 24 h and their use of each occupational tool was analysed second-wise.In both housing systems the cross of chains was used longer for occupation than the other devices. The pendular beam was used least of all. All three devices could have been used by more than one pig at the same time, but the cross of chains was used longer by two to four pigs simultaneously than the others. It was observed that pigs in pens without straw used the cross of chains and the lifting beam significantly (p < 0.05) longer than the pigs in the pens with straw.All three devices are suitable to enrich a housing system without any litter. Especially a cross of chains allows the pigs to perform their explorational behaviour. 相似文献
99.
Modelling carbon and nitrogen dynamics in a bare soil with and without straw incorporation 总被引:2,自引:0,他引:2
P. Garnier ¶ C. Néel C. Aita S. Recous F. Lafolie & B. Mary 《European Journal of Soil Science》2003,54(3):555-568
Incorporating straw into the ploughed layer of soil affects the dynamics of carbon and nitrogen. A precise quantification of its short‐term effect in agricultural fields is difficult because biological and physical processes interact and take place simultaneously. As an alternative to experimentation, investigations have turned to simulations using mechanistic models, and we have taken this approach. The goal of our study was to test a mechanistic and one‐dimensional model of transport and biotransformation (PASTIS) against a data set obtained in a field experiment in northern France. We tested carbon and nitrogen dynamics by measuring C mineralization rates, the rates of gross immobilization and mineralization of N (using 15N tracing), and inorganic pools of N in the soil profile during 1 year in a bare soil with or without addition of wheat straw. Most of the model parameters were determined in independent experiments. We estimated the biological parameters from incubation experiments in the laboratory. The simulated results were in good agreement with experimental data, particularly for gross N rates. Hypotheses concerning the pathway of microbial assimilation and the dependence of decomposition on the size of the biomass were tested. The simulated net N immobilization due to addition of straw (8000 kg dry matter ha?1) reached a maximum of 64 kg N ha?1 after 2 months, whereas the observed value was 66 kg N ha?1. The model indicated that after 13 months the incorporation of straw had reduced the net amount of nitrogen mineralized by 13% and the amount of leached nitrate by 27%. The sensitivity analysis to the depth of straw incorporation indicated that the deeper was the incorporation the less was the leaching and the mineralization of nitrogen. 相似文献
100.
Sulfate yields in eastern Canada, calculated as lake concentration times runoff, are presented on an approximately west to east axis, and are compared with wet deposition data from CANSAP (Canadian Network for Sampling Precipitation) and APN (Air Pollution Network) data on dry deposition. The agreement is very good, and shows clearly that dry deposition is greatest near the center of the continental pollution plume and is less important in remote areas. The good agreement also indicates that most of the sulfate in these lakes is from atmospheric deposition and that there is little retention of sulfate in their watersheds. 相似文献