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151.
González-Martínez MA Brun EM Puchades R Maquieira A Ramsey K Rubio F 《Analytical chemistry》2005,77(13):4219-4227
A fully automated immunosensor for the herbicide glyphosate has been developed on the basis of the immunocomplex capture assay protocol. The sensor carries out on-line analyte derivatization prior to the assay and uses a selective anti-glyphosate serum, a glyphosate peroxidase enzyme tracer, and fluorescent detection. Under optimal conditions, the detection limit achieved is 0.021 microg/L with an analysis rate of 25 min per assay, autonomy of more than 48 h, and sensor reusability >500 analytical cycles. The immunosensor is able to discriminate structurally related molecules, such as aminomethylphosphonic acid, the main metabolite of glyphosate, and other related herbicides, such as glufosinate and glyphosine. Interferences from naturally occurring species (anions, cations, and humic substances) and their elimination were also studied. The immunosensor has been successfully applied to water and soil sample analysis, with good recoveries at levels lower than 1 microg/L. Results obtained with the immunosensor correlate well with data from a magnetic particle ELISA and LC/LC/MS chromatographic method. 相似文献
152.
A study was carried out to increase the CLA contents in ewes’ milk fat under field conditions by dietary means and to investigate
the extent of the changes and consequences for milk processing and cheese quality. During a 3-mon period, ewes’ bulk milk
samples were collected every week from two different herds. For the first 4 wk the ewes were fed a conventional diet. Then
the following 6 wk a supplement enriched in α-linolenate (whole linseed) was incorporated into the ovine diet. Finally, in
the last 3 wk the feeding was the same as in the first 4 wk. The FA profile in milk fat was monitored by GC, and the distribution
of CLA isomers was thoroughly tested by combining GC-MS of 4,4-dimethyloxazoline derivatives (DMOX) with silver ion-HPLC (Ag+-HPLC) of FAME. Reconstructed mass spectral profiles of CLA characteristic ions from DMOX were used to identify positional
isomers, and Ag+-HPLC was used to quantify them. An increase in total CLA in milk fat was observed, and total CLA remained elevated during
the weeks of enriched α-linolenate feeding. In our experimental conditions there was a linear relationship between trans-vaccenic acid (trans-11-octadecenoic acid; trans-11 18∶1) and 9-cis, 11-trans CLA in ewes’ milk fat. Concerning the CLA isomer profile, increases in the 11,13- and 12,14–18∶2 positional isomers were
considerable when linseed was included in the diet. Organoleptic characteristics of cheeses made with CLA-enriched milk did
not substantially differ from those made with nonsupplemented ewes’ milk. CLA total content and isomer profile did not change
during ripening. 相似文献
153.
154.
The diffuse nature of arterial occlusions in Buerger's disease compromises the effect of revascularization. Nevertheless, the muscle branches are quite often unaffected by the occlusive disease making revascularization of collateral arterial branches a promising alternative to conventional procedures. Revascularization by a short autologous venous graft from the grand anastomotic or gastrocnemius artery can be an alternative technique. Advances in microsurgery have made such revascularizations possible. 相似文献
155.
SPETA: Social pervasive e-Tourism advisor 总被引:1,自引:0,他引:1
Angel García-Crespo Javier Chamizo Ismael Rivera Myriam Mencke Ricardo Colomo-Palacios Juan Miguel Gómez-Berbís 《Telematics and Informatics》2009
Tourism is one of the major sources of income for many countries. Therefore, providing efficient, real-time service for tourists is a crucial competitive asset which needs to be enhanced using major technological advances. The current research has the objective of integrating technological innovation into an information system, in order to build a better user experience for the tourist. The principal strength of the approach is the fusion of context-aware pervasive systems, GIS systems, social networks and semantics. This paper presents the SPETA system, which uses knowledge of the user’s current location, preferences, as well as a history of past locations, in order to provide the type of recommender services that tourists expect from a real tour guide. 相似文献
156.
Roberto Sastre Virginia Martín Leoncio Garrido José Luis Chiara Beatriz Trastoy Olga García Angel Costela Inmaculada García‐Moreno 《Advanced functional materials》2009,19(20):3307-3316
Here, the design, synthesis, and characterization of laser nanomaterials based on dye‐doped methyl methacrylate (MMA) crosslinked with octa(propyl‐methacrylate) polyhedral oligomeric silsesquioxane (8MMAPOSS) is reported in relation to their composition and structure. The influence of the silicon content on the laser action of the dye pyrromethene 567 (PM567) is analyzed in a systematic way by increasing the weight proportion of POSS from 1 to 50%. The influence of the inorganic network structure is studied by replacing the 8MMAPOSS comonomer by both the monofunctionalized heptaisobutyl‐methacryl‐POSS (1MMAPOSS), which defines the nanostructured linear network with the POSS cages appearing as pendant groups of the polymeric chains, and also by a new 8‐hydrogenated POSS incorporated as additive to the polymeric matrices. The new materials exhibit enhanced thermal, optical, and mechanical properties with respect to the pure organic polymers. The organization of the molecular units in these nanomaterials is studied through a structural analysis by solid‐state NMR. The domain size of the dispersed phase assures a homogeneous distribution of POSS into the polymer, thus, a continuous phase corresponding to the organic matrix incorporates these nanometer‐sized POSS crosslinkers at a molecular level, in agreement with the transparency of the samples. The silicon–oxygen core framework has to be covalently bonded into the polymer backbone instead of being a simple additive and both the silica content and crosslinked degree exhibit a critical influence on the laser action. 相似文献
157.
Antonio González‐Sarrías Juan A. Giménez‐Bastida María T. García‐Conesa María B. Gómez‐Sánchez Noelia V. García‐Talavera Angel Gil‐Izquierdo Carmen Sánchez‐Álvarez Luis O. Fontana‐Compiano Juan P. Morga‐Egea Francisco A. Pastor‐Quirante Francisco Martínez‐Díaz Francisco A. Tomás‐Barberán Juan Carlos Espín 《Molecular nutrition & food research》2010,54(3):311-322
Epidemiology supports the important role of nutrition in prostate cancer (PCa) prevention. Pomegranate juice (PJ) exerts protective effects against PCa, mainly attributed to PJ ellagitannins (ETs). Our aim was to assess whether ETs or their metabolites ellagic acid and urolithins reach the human prostate upon consumption of ET‐rich foods and to evaluate the effect on the expression of three proliferation biomarkers. Sixty‐three patients with BPH or PCa were divided into controls and consumers of walnuts (35 g walnuts/day) or pomegranate (200 mL PJ/day) for 3 days before surgery. Independently of the ETs source, the main metabolite detected was urolithin A glucuronide, (3,8‐dihydroxy‐6H‐dibenzo[b,d]pyran‐6‐one glucuronide) (up to 2 ng/g) together with the traces of urolithin B glucuronide, (3‐hydroxy‐6H‐dibenzo[b,d]pyran‐6‐one glucuronide) and dimethyl ellagic acid. The small number of prostates containing metabolites was likely caused by clearance of the compounds during the fasting. This was corroborated in a parallel rat study and thus the presence of higher quantities of metabolites at earlier time points cannot be discarded. No apparent changes in the expression of CDKN1A, MKi‐67 or c‐Myc were found after consumption of the walnuts or PJ. Our results suggest that urolithin glucuronides and dimethyl ellagic acid may be the molecules responsible for the beneficial effects of PJ against PCa. 相似文献
158.
159.
Teresa Ortega Elena De La Hera M. Emilia Carretero Pilar Gómez-Serranillos M. Victoria Naval Angel M. Villar Marin Prodanov Visitación Vacas Teresa Arroyo Teresa Hernández Isabel Estrella 《European Food Research and Technology》2008,227(6):1641-1650
Red wine has been reported to exert beneficial effects in preventing cardiovascular diseases probably due to their polyphenols
constituents. The vasorelaxant capacity and phenolic composition of four monovarietal young red wines Merlot, Tempranillo,
Garnacha and Cabernet-Sauvignon obtained from grapes from 2004 vintage, cultivated under the same climatic and agricultural
conditions, wine-making technology and storage conditions, were determined using vascular reactivity assay in rat aortic and
high-performance liquid chromatography, respectively. Primary cultures of vascular smooth muscle cells from Wistar rats were
also used to evaluate their survival prevention activity as well. Every studied wine present vasorelaxation effect, but the
higher value corresponds to the analyzed Merlot wine, especially rich in phenolic compounds, mainly catechins and oligomeric
proanthocyanidins and anthocyanin glycosides. This study further demonstrated previous investigations about the phenolic composition
of wines relation with their vasorelaxation activity. 相似文献
160.
Sántiz-Gómez Marco Antonio Mazorra-Manzano Miguel Angel Ramírez-Guerra Hugo Enrique Scheuren-Acevedo Susana María Navarro-García Gerardo Pacheco-Aguilar Ramón Ramírez-Suárez Juan Carlos 《Food science and biotechnology》2019,28(3):751-757
Food Science and Biotechnology - Chemical properties of fish gelatins differ from those of conventional mammalian sources, representing an attractive technological alternative for the food... 相似文献