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991.
Stalmach A Edwards CA Wightman JD Crozier A 《Journal of agricultural and food chemistry》2011,59(17):9512-9522
Analysis of Concord grape juice by HPLC with ESI-MS(n), PDA, and fluorescence detection resulted in the identification and quantification of 60 flavonoids and related phenolic compounds, which were present at an overall concentration of 1508 ± 31 μmol/L. A total of 25 anthocyanins were detected, which were mono- and di-O-glucosides, O-acetylglucosides, O-p-coumaroyl-O-diglucosides, and O-p-coumaroylglucosides of delphinidin, cyanidin, petunidin, peonidin, and malvidin. The anthocyanins represented 46% of the total phenolic content of the juice (680 μmol/L). Tartaric esters of hydroxycinnamic acids, namely, trans-caftaric and trans-coutaric acids, and to a lesser extent trans-fertaric acid accounted for 29% of the phenolic content, with a total concentration of 444 μmol/L, of which 85% comprised trans-caftaric acid. Free hydroxycinnamic acids were also quantified but contributed to <1% of the total phenolic content (8.4 μmol/L). The other groups of polyphenolic compounds present in the juice, accounting for 24% of the total, comprised monomeric and oligomeric units of (epi)catechin and (epi)gallocatechin (248 μmol/L), flavonols (76 μmol/L), gallic acid (51 μmol/L), and trans-resveratrol (1.5 μmol/L). The bioavailability of the (poly)phenolic compounds in 350 mL of juice was investigated following acute intake by healthy volunteers. Plasma and urine were collected over 0-24 h and analyzed for parent compounds and metabolites. In total, 41 compounds, principally metabolites, were identified. 相似文献
992.
HPLC with PDA and MS(2) detection was used to identify and quantify flavonoids in the tropical citrus species Citrus microcarpa , Citrus hystrix , Citrus medica var. 1 and 2, and Citrus suhuiensis . Most of these species contained high amounts of flavones, flavanones, and dihydrochalcone C- and/or O-glycosides, which were identified on the basis of HPLC retention times, cochromatography with available authentic standards, absorbance spectra, and mass spectral fragmentation patterns. Among the major compounds detected were apigenin-6,8-di-C-glucoside, apigenin-8-C-glucosyl-2″-O-rhamnoside, phloretin-3',5'-di-C-glucoside, diosmetin-7-O-rutinoside, hesperetin-7-O-neohesperidoside, and hesperetin-7-O-rutinoside. Most of the dihydrochalcone and flavone C-glycosides have not previously been detected in tropical citrus. C. microcarpa contained a high amount of phloretin-3',5'-di-C-glucoside. Most of the tropical citrus flavanones were neohesperidoside conjugates, which are responsible for imparting a bitter taste to the fruit. Only C. suhuiensis fruit contains rutinoside, a nonbitter conjugate. 相似文献
993.
Zhou J Berman KH Breeze ML Nemeth MA Oliveira WS Braga DP Berger GU Harrigan GG 《Journal of agricultural and food chemistry》2011,59(21):11652-11656
The compositions of a diverse range of commercially available conventional and genetically modified (GM; glyphosate-tolerant) soybean varieties from maturity groups 8 and 5, respectively, grown in the northern and southern soybean regions of Brazil during the 2007-2008 and 2008-2009 growing seasons were compared. Compositional analyses included measurement of essential macro- and micronutrients, antinutrients, and selected secondary metabolites in harvested seed as well as measurement of proximates in both forage and harvested seed. Statistical comparisons utilized a mixed analysis of variance model to evaluate the relative contributions of growing season, soybean growing region, production site, phenotype (GM or conventional), and variety. The study highlighted extensive variability in the overall data set particularly for components such as fatty acids, vitamin E, and isoflavones. There were few differences between the GM and non-GM populations, and most of the variability in the data set could be attributed to regional and variety differences. Overall, the results were consistent with the expanding literature on the lack of any meaningful impact of transgene insertion on crop composition. 相似文献
994.
Connelley T Storset AK Pemberton A Machugh N Brown J Lund H Morrison IW 《Veterinary research》2011,42(1):37
ABSTRACT: Natural killer (NK) cells are well recognized as playing a key role in innate immune defence through cytokine production and cytotoxic activity; additionally recent studies have identified several novel NK cell functions. The ability to study NK cells in the sheep has been restricted due to a lack of specific reagents. We report the generation of a monoclonal antibody specific for ovine NKp46, a receptor which in a number of mammals is expressed exclusively in NK cells. Ovine NKp46+ cells represent a population that is distinct from CD4+ and γδ+ T-cells, B-cells and cells of the monocytic lineage. The NKp46+ cells are heterogenous with respect to expression of CD2 and CD8 and most, but not all, express CD16 - characteristics consistent with NK cell populations in other species. We demonstrate that in addition to populations in peripheral blood and secondary lymphoid organs, ovine NKp46+ populations are also situated at the mucosal surfaces of the lung, gastro-intestinal tract and non-gravid uterus. Furthermore, we show that purified ovine NKp46+ populations cultured in IL-2 and IL-15 have cytotoxic activity that could be enhanced by ligation of NKp46 in re-directed lysis assays. Therefore we conclude that ovine NKp46+ cells represent a population that by phenotype, tissue distribution and function correspond to NK cells and that NKp46 is an activating receptor in sheep as in other species. 相似文献
995.
Motta RO Cunha LM Leite RC da Silva IJ Pinto AC Braga EM da Cunha AP de Oliveira PR 《Journal of zoo and wildlife medicine》2011,42(3):399-407
This study aims to establish the hematological values of Crotalus durissus collilineatus snakes captured in Brazil as well as to verify the effects of hematozoan infection on these snakes. Eighty-three blood samples were drawn from C. d. collilineatus specimens for analysis. The sample set was composed of 30 males and 30 females, recently caught from the wild, and 11 males and 12 females bred in captivity. Blood samples were used to determine red blood cell counts, white blood cell counts, thrombocyte counts, hematocrit values, hemoglobin concentration, and total plasma protein. Blood smears were used to diagnose Hepatozoon spp. infection and to calculate the parasitic load in the sample as well as the percentage of immature red cells. Results obtained for the wild-caught animals, with and without parasites, were compared among themselves and with the values obtained for the captive-bred animals. Hematological values for C. durissus were established. Wild-caught snakes had an infection rate of 38.3%, while no Hepatozoon sp. infection was detected in the captive-bred animals. The snakes which were not infected by the Hepatozoon sp. exhibited average weight, length, and weight-length ratios higher than those of the infected animals. An increase in immature red cells was noted in the Hepatozoon-infected snakes. 相似文献
996.
PABLO GÓMEZ‐OCHOA FRANCISCO LLABRÉS‐DÍAZ SERGIO RUIZ ANDREA CORDA SAUL PRIETO IVÁN SOSA TOMMASO GREGORI MANUEL GASCÓN GUILLERMO C. COUTO 《Veterinary radiology & ultrasound》2011,52(1):103-106
We describe the use of ultrasonography‐guided percutaneous splenic injection of agitated saline and heparinized blood for the diagnosis of portosystemic shunts (PSS) in 34 dogs. Agitated saline mixed with 1 ml of heparinized autologous blood was injected into the spleen of 34 sedated dogs under sonographic guidance. The transducer was then sequentially repositioned to visualize the portal vein, the caudal vena cava, and the right atrium through different acoustic windows. It was possible to differentiate between intrahepatic and extrahepatic shunts depending on the entry point of the microbubbles into the caudal vena cava. Portoazygos shunts and portocaval shunts could be differentiated based on the presence of microbubbles in the caudal vena cava and/or the right atrium. In one dog, collateral circulation due to portal hypertension was identified. In dogs with a single extrahepatic shunt, the microbubbles helped identify the shunting vessel. The technique was also used postoperatively to assess the efficacy of shunt closure. All abnormal vessels were confirmed by exploratory laparotomy or with ultrasonographic identification of the shunting vessel. Ultrasound‐guided transsplenic injection of agitated saline with heparinized blood should be considered as a valuable technique for the diagnosis of PSS; it is easy to perform, safe, and the results are easily reproducible. 相似文献
997.
Yogesh Chander Simone Oliveira Sagar M. Goyal 《Veterinary journal (London, England : 1997)》2011,187(1):139-141
A PCR based method was developed for the identification of ceftiofur resistance genes (blaCMY-2, blaTEM-1, and ampC) in swine bacterial pathogens. Using this method, the ceftiofur resistant (n = 76) and susceptible (n = 45) strains of Bordetella bronchiseptica, Salmonella spp., Escherichia coli, and Pasteurella multocida were screened for the presence of these three genes. The resistant genes were detected in 70% (blaTEM-1), 68% (blaCMY-2) and 45% (ampC) of the resistant isolates and in 18% (blaTEM-1), 27% (blaCMY-2), and 36% (ampC) of the susceptible isolates. Results obtained in the present study showed widespread distribution of these three resistance genes in ceftiofur-resistant swine pathogens. It was also observed that more pathogens are acquiring these resistance genes. 相似文献
998.
The occurrence of coligranulomatosis in a Brazilian flock of 1500 8-to-12-month-old coturnix quail is described. The disease caused an 85% drop in egg production and 15% mortality. Lesions were located on the mesentery, intestines, gizzard, heart, oviducts, ovaries, and liver. Samples of these organs were submitted for bacteriological culture, isolation, identification, pathogenicity assay by inoculation of diluted cultures into healthy hens, and histopathology. 相似文献
999.
Eric de Madron Dr Med Vet Alan Kadish MD Joseph F. Spear PhD David H. Knight DVM MMedSc 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1987,1(4):163-169
In a dog, tricuspid regurgitation due to congenital tricuspid dysplasia resulted in extreme right heart enlargement and right heart failure. Incessant supraventricular tachycardias were present, requiring the intravenous administration of verapamil to reduce the ventricular rate. Oral therapy using a combination of verapamil and quinidine was partially effective in controlling the ventricular rate during the following week. At that time, electrophysiologic studies were performed. They revealed that a succession of several atrial tachycardias with different cycle lengths, including one episode of atrial flutter, was present. Atrial activity was spanning the majority of the cycle length in all these arrhythmias. Epicardial mapping was performed during the atrial flutter. This enabled the detection of a depolarization wave-front traveling counterclockwise from the dorsolateral right atrium toward the right appendage, following the tricuspid valve annulus. No areas of abnormal conduction were detected. Because programmed electric stimulation maneuvers could not be performed, definitive conclusions about the mechanism of the arrhythmia could not be drawn. The two most likely possibilities were circus movement using part of the dilated tricuspid valve annulus as an anatomic barrier or a leading circle type of re-entry. 相似文献
1000.
Alan Noble 《Pest management science》1985,16(4):349-354
In order to determine the effect of pH and temperature on post-harvest dip solutions of dimethoate (500 mg litre?1), the half-lives and pseudo first-order rate constants were calculated from measurements at pH 4, 6, 8, 10, 11.5, and at two temperatures 25 and 52°C. The half-lives ranged from 206 days to 39.3 min at 25°C, and from 5.6 days to 205s at 52°C; the rate constants ranged from 3.9 × 10?8 s?1 to 2.9 × 10?4 s?1 at 25°C, and from 1.4 × 10?6 s?1 to 3.4 × 10?3 s?1 at 52°C. The results show that the water used in dips should have a pH≤7. The addition of benomyl to the dip solutions at two concentrations (0.5 and 1.0 g litre?1) had no effect on the half-lives and rate constants. The use of hard and salted waters in dips also showed no major effect. A formula was developed that gives the half-life of the dimethoate as a function of the pH and temperature. 相似文献