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排序方式: 共有542条查询结果,搜索用时 31 毫秒
41.
Olsson ME Ekvall J Gustavsson KE Nilsson J Pillai D Sjöholm I Svensson U Akesson B Nyman MG 《Journal of agricultural and food chemistry》2004,52(9):2490-2498
Four cultivars of strawberries (Senga Sengana, BFr77111, Elsanta, and Honeoye) were studied for their content of antioxidants, total antioxidant capacity, and low molecular weight carbohydrates in relation to harvest year, ripening stage, and cold storage. For ascorbic acid, chlorogenic acid, ellagic acid, and total antioxidative capacity, measured in both water-soluble and water-insoluble extracts, there was a 2-5-fold variation among cultivars. Unripe berries contained lower concentrations of chlorogenic acid and p-coumaric acid and also quercetin and kaempferol compared with riper berries. During cold storage for up to 3 days, relatively few changes in the concentration of the different antioxidants occurred. The concentrations of several investigated parameters were interrelated, for example, for ascorbic acid and water-soluble antioxidant capacity and for ellagic acid and water-insoluble antioxidant capacity. The dominating sugars in strawberries were fructose and glucose, but considerable amounts of sucrose were also present, and their contents varied among cultivars, giving a predicted glycemic index of approximately 81. Verbascose, raffinose, and stachyose were found in only minor amounts. The study shows that the concentration of a number of bioactive compounds in strawberries varied according to cultivar, ripening stage, and storage. This information should make it possible to select strawberries with an optimal content of bioactive compounds. 相似文献
42.
This study was undertaken to determine the level of resistance against pyrantel citrate in strains of Oesophagostomum quadrispinulatum and Oesophagostomum dentatum which have previously been found resistant to this anthelmintic. Groups of pigs were artificially infected with batches of infective larvae which were previously found either susceptible or resistant to pyrantel citrate. After treatment with 1, 2 and 4 times the recommended dose (14 mg kg-1) of pyrantel citrate, the resistant O. quadrispinulatum population was reduced by 51.0, 76.2 and 86.1%, and O. dentatum by 41.2, 47.9 and 78.5%. The results indicated that O. dentatum was slightly more resistant (P less than 0.05) than O. quadrispinulatum to pyrantel citrate. Treatment of the susceptible worms with 1 and 2 times the recommended dose caused a reduction in worm numbers by 61.0 and 99.4%, respectively. 相似文献
43.
A total of nine Trichinella nativa isolates were compared by amplified fragment length polymorphism (AFLP). Four hundred nanograms of genomic DNA from a pool of 10--20 larvae were digested using HindIII and MseI restriction endonucleases. Of the 16 primer combinations initially tested, Hind-C and Mse-C primers showed rich polymorphism with approximately 40--90 bands in the range of 30--270 bp. Genetic similarities were estimated visually. AFLP provided discriminatory banding patterns and may therefore be used as a method for detecting variation in T. nativa populations. However, the heterogeneous patterns obtained from pooled samples emphasize the need for further development of the sampling and numerical analysis of the patterns for epidemiological and taxonomical interpretation. 相似文献
44.
Three hundred and eighty-four Staphylococcus aureus isolates obtained from mammary secretions from 332 ewes kept for meat production were typed by pulsed-field gel electrophoresis (PFGE). The ewes were from 242 flocks located in 13 counties distributed in four regions of Norway. In total, 64 different pulsotypes were identified, 31 of these were represented by a single isolate. Fifty-nine percent of the isolates belonged to one of five closely related pulsotypes. This group of pulsotypes occurred in all the counties. Although widely disseminated, the proportions of the prevalent and closely related pulsotypes differed between the regions. Nine pulsotypes were unique to single regions but the number of isolates belonging to each of these pulsotypes was low. Resistance to penicillin was found in only 3 of the 384 S. aureus isolates. These represented three different single banding patterns, not related to any of the prevalent pulsotypes found. 相似文献
45.
van Klaveren NJ Suwankong N De Boer S van den Brom WE Voorhout G Hazewinkel HA Meij BP 《Veterinary surgery : VS》2005,34(5):450-456
OBJECTIVE: Using force plate analysis (FPA), determine ground reaction forces in dogs with degenerative lumbosacral stenosis (DLS) and evaluate the effects of lumbosacral decompressive surgery. STUDY DESIGN: Prospective clinical study. ANIMALS: Twelve dogs with DLS. METHODS: DLS was diagnosed by clinical signs, radiography, computed tomography, and/or magnetic resonance imaging. FPA was performed before surgery, and 3 days, 6 weeks, and 6 months after surgery. The mean peak braking (Fy+), peak propulsive (Fy-), and peak vertical (Fz+) forces of 8 consecutive strides were determined. The ratio between the total Fy- of the pelvic limbs and the total Fy- of the thoracic limbs (P/TFy-), reflecting the distribution of Fy-, was analyzed to evaluate any changes in locomotion pattern postoperatively. Ground reaction force data for DLS dogs were compared with data derived from 24 healthy dogs (control). RESULTS: In dogs with DLS, the propulsive forces (Fy-) of the pelvic limbs were significantly smaller than those of controls. P/TFy- was significantly smaller in dogs with DLS than in control dogs, and increased during the follow-up period, reaching normal values 6 months after surgery. CONCLUSIONS: Cauda equina compression in dogs with DLS decreases the propulsive force of the pelvic limbs and surgical treatment restores the propulsive force of the pelvic limbs in a 6-month period. CLINICAL RELEVANCE: In dogs with DLS, FPA is an effective method in evaluating the response to surgical treatment. Normal propulsive force in the pelvic limbs was restored during 6 months after decompressive surgery. 相似文献
46.
47.
von Blumröder D Schares G Norton R Williams DJ Esteban-Redondo I Wright S Björkman C Frössling J Risco-Castillo V Fernández-García A Ortega-Mora LM Sager H Hemphill A van Maanen C Wouda W Conraths FJ 《Veterinary parasitology》2004,120(1-2):11-22
Various existing serological tests were compared with a standard panel of 523 sera in a multicentred study across Europe. Well characterised sera from animals that were experimentally or naturally infected with Neospora caninum as well as sera from cattle deemed uninfected with N. caninum were provided by the participants of the study and analysed in several commercial (CHEKIT Dr. Bommeli/Intervet, CIVTEST BOVIS NEOSPORA Hipra, Cypress Diagnostics C.V., Herd Check IDEXX, Mastazyme MAST Diagnostics, P38-ELISA Animal Welfare and Food Safety GmbH (AFOSA)) as well as in-house assays (five ELISAs and one IFAT). Most tests showed a high level of agreement in the interpretation of the test results (positive or negative). A further distinct increase in agreement between tests was obtained after the application of standardised cut-offs offered by a two-graph receiver operating characteristic analysis. This procedure allows a standardised interpretation of results obtained with different tests used in independent, parallel seroepidemiological studies. 相似文献
48.
Fecal samples from poultry on farms established after the ban of avoparcin (study farms) and from poultry on farms previously exposed to avoparcin (control farms) were examined for the presence of vancomycin-resistant enterococci (VRE). The samples were collected during the autumn and winter of 2001-2002. One isolate from each positive sample was selected, identified to species level, and examined for the presence of the vanA gene. The concentration of VRE and generic enterococci in the samples were also determined. In addition, the susceptibility to the ionophoric coccidiostat narasin was examined in a number of enterococcal isolates from poultry and in some enterococci of porcine origin that had not been exposed to narasin. VanA-type VRE was detected in samples from 64% of the study farms and 96% of the control farms. However, the concentration of VRE in the control samples was about six times larger than in the samples from the study farms. The minimum inhibitory concentration values for narasin differed between the poultry (1-4 mg/liter) and the porcine (0.25-0.5 mg/liter) isolates, indicating a decreased susceptibility towards narasin among enterococci from poultry. 相似文献
49.
Viboud C Bjørnstad ON Smith DL Simonsen L Miller MA Grenfell BT 《Science (New York, N.Y.)》2006,312(5772):447-451
Quantifying long-range dissemination of infectious diseases is a key issue in their dynamics and control. Here, we use influenza-related mortality data to analyze the between-state progression of interpandemic influenza in the United States over the past 30 years. Outbreaks show hierarchical spatial spread evidenced by higher pairwise synchrony between more populous states. Seasons with higher influenza mortality are associated with higher disease transmission and more rapid spread than are mild ones. The regional spread of infection correlates more closely with rates of movement of people to and from their workplaces (workflows) than with geographical distance. Workflows are described in turn by a gravity model, with a rapid decay of commuting up to around 100 km and a long tail of rare longer range flow. A simple epidemiological model, based on the gravity formulation, captures the observed increase of influenza spatial synchrony with transmissibility; high transmission allows influenza to spread rapidly beyond local spatial constraints. 相似文献
50.
Faecal samples were collected from 1,190 wild cervids in Norway and analyzed for cysts/oocysts of the protozoan parasites Giardia and Cryptosporidium. Samples were from calves, yearlings and adults of moose (Alces alces), red deer (Cervus elaphus), roe deer (Capreolus capreolus) and reindeer (Rangifer tarandus) shot during the hunting season. Cryptosporidium was found in 15 (3.3%) of 455 moose, 1 (0.3%) of 289 red deer, 18 (6.2%) of 291 roe deer, but was not found in any of 155 reindeer. Giardia was found in 56 (12.3%) moose, 5 (1.7%) red deer, 45 (15.5%) roe deer and 11 (7.1%) reindeer. The calves had the highest prevalence of infection, but this was only statistically significant for Giardia in moose and for Cryptosporidium and Giardia in roe deer. Calves generally had the highest intensity of infection, but this difference was only statistically significant for calves with Giarda and the highest intensity of infection. Both Giardia and Cryptosporidium were found in samples from several geographical areas, indicating that these parasites are distributed among the cervid population in all parts of Norway, especially in moose and roe deer. This is the first published report of Cryptosporidium in moose and of Giardia in reindeer. 相似文献