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961.
Mardones F Urrutia MT Villarroel L Rioseco A Castillo O Rozowski J Tapia JL Bastias G Bacallao J Rojas I 《Public health nutrition》2008,11(1):30-40
OBJECTIVE: To test the hypothesis that maternal food fortification with omega-3 fatty acids and multiple micronutrients increases birth weight and gestation duration, as primary outcomes. DESIGN: Non-blinded, randomised controlled study. SETTING: Pregnant women received powdered milk during their health check-ups at 19 antenatal clinics and delivered at two maternity hospitals in Santiago, Chile. SUBJECT: Pregnant women were assigned to receive regular powdered milk (n = 477) or a milk product fortified with multiple micronutrients and omega-3 fatty acids (n = 495). RESULTS: Intention-to-treat analysis showed that mean birth weight was higher in the intervention group than in controls (65.4 g difference, 95% confidence interval (CI) 5-126 g; P = 0.03) and the incidence of very preterm birth (0.80 just for mean birth weight and birth length in the on-treatment analysis; birth length in that analysis had a difference of 0.57 cm (95% CI 0.19-0.96 cm; P = 0.003). CONCLUSIONS: The new intervention resulted in increased mean birth weight. Associations with gestation duration and most secondary outcomes need a larger sample size for confirmation. 相似文献
962.
Guillén-Casla V Pérez-Arribas LV León-González ME Polo-Díez LM 《Journal of agricultural and food chemistry》2008,56(7):2303-2309
Simple one- and two-dimensional high-performance liquid chromatography (HPLC) methods for the simultaneous enantiomeric determination of alkyloxyphenoxypropionic acid herbicides is presented. Compounds studied were ( R, S)-2-[4-(2,4-dichlorophenoxy)phenoxy]propionic acid (diclofop-acid) and ( R, S)-2-[4-(2,4-dichlorophenoxy)]methyl propionate (diclofop-methyl). Mobile phases necessary to separate their enantiomers on an alpha1-acid glycoprotein chiral stationary phase are different; therefore, the simultaneous separation by an isocratic mode is not possible. The chiral separation method proposed involves a one-step gradient allowing for the simultaneous determination of both racemic enantiomers. Detection limits of the method were 0.03 mg/L for both diclofop-acid enantiomers and 0.14 and 0.15 mg/L for diclofop-methyl enantiomers, respectively. The two-dimensional method involves the use of two chromatographs in one achiral-chiral coupling. The LC-LC method is more suitable for complex samples because it involves an online cleanup effect. Detection limits were 1.25 and 1.87 mg/L for diclofop-acid and 2.70 and 3.02 mg/L for diclofop-methyl enantiomers, respectively. Accuracy, repeatability, and reproducibility have been studied in standard samples and a technical product. 相似文献
963.
Miguel A. Ortega Huerta 《Biological conservation》2007,134(1):83-95
Patterns of fragmentation in current distributions of 35 species of birds and 19 species of mammals that are considered endangered, threatened, or with restricted distributions were modeled in relation to 3 biosphere reserves (El Abra-Tanchipa, El Cielo, Sierra Gorda; ‘BRs’) and 13 areas identified as priorities for conservation in northeastern Mexico (PAC-Priority Areas for Conservation). Core area percentage of landscape (CPLAND) and aggregation index (AI) were used to summarize fragmentation trends in species’ geographic distributions, modeled using ecological niche modeling techniques. Overall (median) CPLAND and AI revealed: (a) for birds, El Abra-Tanchipa BR and neighboring areas exhibited the lowest fragmentation (high CPLAND and high AI), whereas Sierra Gorda BR was the most fragmented; (b) for mammals, El Abra-Tanchipa and El Cielo BRs exhibited lowest overall fragmentation, while Sierra Gorda BR was the most fragmented. Although there were areas (i.e., El Abra-Tanchipa BR and Parras de la Fuente PAC) with higher combination of CPLAND and AI values, El Cielo BR stands out because of its high CPLAND and AI values along with the highest species richness. 相似文献
964.
Granado-Serrano AB Martín MA Izquierdo-Pulido M Goya L Bravo L Ramos S 《Journal of agricultural and food chemistry》2007,55(5):2020-2027
Dietary polyphenols have been associated with reduced risk of chronic diseases, but the precise molecular mechanisms of protection remain unclear. This work was aimed at studying the effect of (-)-epicatechin (EC) and chlorogenic acid (CGA) on the regulation of apoptotic and survival/proliferation pathways in a human hepatoma cell line (HepG2). EC or CGA treatment for 18 h had a slight effect on cell viability and decreased reactive oxygen species formation, and EC alone promoted cell proliferation, whereas CGA increased glutathione levels. Phenols neither induced the caspase cascade for apoptosis nor affected expression levels of Bcl-xL or Bax. A sustained activation of the major survival signals AKT/PI-3-kinase and ERK was shown in EC-treated cells, rather than in CGA-exposed cells. These data suggest that EC and CGA have no effect on apoptosis and enhance the intrinsic cellular tolerance against oxidative insults either by activating survival/proliferation pathways or by increasing antioxidant potential in HepG2. 相似文献
965.
966.
Rosa Ana Pérez Consuelo Sánchez-Brunete Beatriz Albero Esther Miguel José Luis Tadeo Juan Alonso 《Compost science & utilization》2016,24(3):190-202
The quality of three types of treated sludges (sludge from the paper recycling industry, and sewage sludge treated by composting with pruning waste and thermally dried) was assessed in this work. The amendments were physicochemically characterized and evaluated for their microbiological quality and for contamination with pollutants. All three organic amendments showed an absence of pathogens, so they are microbially suitable for agricultural use. The pollutants studied in the amendments included eight heavy metals and 83 organic compounds. Heavy metals, pesticides, polycyclic aromatic hydrocarbons, octylphenol, bisphenol A, and parabens were found in the organic amendments. The amount and type of contaminants depended on the sample sources and differed between samples from a single origin. The presence of some of the pollutants found has not been previously reported in organic amendments. The germination assay showed that these amendments may be applied to soil in controlled doses. As far as we know, this is the first reported study that has evaluated a great variety of pollutants (heavy metals, pesticides, persistent and emerging organic pollutants) in sludge from the recycled paper industry; moreover, studies in other waste products in which such a broad range of pollutants has been evaluated have been scarce until now due to the complexity of these matrices. 相似文献
967.
Use of a byproduct of magnesium oxide production to precipitate phosphorus and nitrogen as struvite from wastewater treatment liquors 总被引:3,自引:0,他引:3
Quintana M Colmenarejo MF Barrera J García G García E Bustos A 《Journal of agricultural and food chemistry》2004,52(2):294-299
This paper describes a series of experiments designed to recover phosphorus and nitrogen from sewage in the form of struvite (MgNH(4)PO(4).6H(2)O), a potential fertilizer. Nitrogen and phosphate were recovered from a filtrate of digested sludge dewatered at the Arroyo del Soto Waste Water Treatment Plant (WWTP) (Madrid, Spain). A byproduct of the Spanish magnesite mining and MgO production industry was used as the magnesium source. The precipitating performance of this byproduct was compared to that of conventional chemical reagents such as pure MgO. The precipitates obtained were subjected to chemical, light microscopy, and X-ray diffraction analysis. The findings indicate the precipitate recovered using this byproduct contains several minerals with a predominance of struvite. Optimal purity ( approximately 80% struvite) was achieved using the sieved <0.04 mm grain size fraction of the byproduct at doses corresponding to a molar Mg:P ratio of 1.6. 相似文献
968.
Fernández-Cruz ML Villarroya M Llanos S Alonso-Prados JL García-Baudín JM 《Journal of agricultural and food chemistry》2004,52(4):860-863
Field trials have been carried out to determine the variability of residue levels of fenitrothion and its main metabolites fenitrothion-oxon and 3-methyl-4-nitrophenol in individual kaki fruits versus composite samples, in peel versus flesh, and in whole uncooked versus whole cooked fruits. Residue levels have been determined by gas chromatography with thermionic specific detection after extraction with ethyl acetate and without further cleanup. At harvest, residue levels of fenitrothion were below maximum residue levels (MRLs) and the two metabolites 3-methyl-4-nitrophenol and fenitrothion-oxon could be quantified with average amounts of 0.080 and 0.012 mg/kg, respectively. Levels of fenitrothion decreased 88% after peeling, whereas temperature did not result in a high variation. The ratios of the highest residue level in the individual fruits to the corresponding mean of residue levels in the composite samples for fenitrothion were <3. This value is lower than that recommended by the World Health Organization as default value for consumer risk assessment. 相似文献
969.
Summary The conuco in Cuba is a large garden or a small field where agriculture is practiced in a traditional way. The history of the conuco is discussed. Composition and structure of actual conucos are described on the basis of four cases studied in Eastern Cuba. Their cultivated plants came from nearly all regions of diversity of the world. The crops from the Central American and Mexican region are most important. The great diversity of different crops as well as the marked variation within most of the cultivated plants stress the importance of the conuco as a reservoir for plant genetic resources.
Der Conuco — ein bedeutendes Reservoir für pflanzliche genetische Ressourcen in Kuba
Zusammenfassung Der kubanische Conuco ist ein größerer Garten oder ein kleineres Feld mit traditioneller landwirtschaftlicher Produktion. Die Geschichte des Conuco wird diskutiert. Zusammensetzung und Struktur aktueller Conucos werden auf der Grundlage von vier ostkubanischen ausgewählten Fallbeispielen beschrieben. Ihre Kulturpflanzen stammen beinahe aus allen Mannigfaltigkeitszentren der Welt. Besonders bedeutsam sind die Kulturpflanzen der mittelamerikanischen und mexikanischen Region. Die große Mannigfaltigkeit unterschiedlicher Fruchtarten und die ausgeprägte infraspezifische Variabilität bei den meisten Kulturpflanzen unterstreichen die Bedeutung des Conuco als Reservoir für pflanzliche genetische Ressourcen.
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970.