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371.
A microsatellite DNA-based method for Vitis vinifera grape must authentication is presented. Five of the most important port wine producing grape cultivars (Tinta Roriz, Tinto C?o, Touriga Francesa, Touriga Nacional, and Tinta Barroca) were typed at four microsatellite loci described by Bowers et al. (Genome 1996, 39, 628-633) and Thomas and Scott (Theor. Appl. Genet. 1993, 86, 985-990). The corresponding 5 varietal musts and 26 must mixtures that result from the combination of the five varieties were also typed at the four loci. There were no differences between the corresponding leaf and varietal must profiles. All must combinations showed the expected band profiles corresponding to the sum of the varietal band profile components. Among the 26 must mixtures, 8 could be discriminated using the four loci.  相似文献   
372.
Terra Quente, situated in the province of Trás-os-Montes (northeast of Portugal), is one of the most important olive growing areas of Portugal. In this region, which is extremely hot and dry during summer, losses due to the olive fly, Bactrocera oleae (Rossi), are highly variable between years, with estimates ranging from 16.3 to 98.8% of infested fruits. The objective of this study was to test the use of the degree-days models, based in a daily accumulation of temperature (°DD) to predict insect activity in the field and timing control measures, in such a climatic condition. Seasonal flight activity periods and insect development were studied from 2005 to 2008 in traditional olive groves and a degree-day model was developed for predicting the development of olive fly second generation, which is the one that can cause losses. It was found that, while the use of these models could be hampered by high temperatures and low relative humidity prevailing during summer, they may have some potential as a tool for the management of B. oleae populations, allowing the identification with acceptable error of the main second generation events. Results indicated that, if adulticide sprays are to be used, the spray-window for their applications lasts between an accumulation, since January 1, of 1837.20 ± 35.82°DD8.99, which corresponds to the beginning of the insect second flight and 2045.87 ± 34.30°DD8.99, which corresponds to its main peak.  相似文献   
373.
Plant Foods for Human Nutrition - Phenolic compounds in camu-camu (Myrciaria dubia) have received interest due to their health-promoting effects. However, these compounds have been poorly...  相似文献   
374.
OBJECTIVE: To identify individual and contextual factors associated with the practice of exclusive breast-feeding (EBF). METHODOLOGY: We analysed 34 435 children under 6 months of age living in 111 municipalities in the state of S?o Paulo, south-eastern Brazil, who participated in a survey investigating feeding practices during the first year of life, carried out during the 1999 national vaccination campaign. The questionnaire employed included questions on the consumption, in the last 24 h, of breast milk, water, tea, other types of milk and other foods, in addition to mother and child characteristics. Information on the pro-breast-feeding measures implemented in the municipalities was also collected. The effects of individual and contextual characteristics on EBF were analysed using multilevel models. RESULTS: The final model showed a greater chance of EBF in women with tertiary education (odds ratio (OR) = 1.91; 95% confidence interval (CI) 1.75-2.06); women aged between 25 and 29 years (OR = 1.52; 95% CI 1.41-1.63); multiparae (OR = 1.42; 95% CI 1.33-1.49); female babies (OR = 1.12; 95% CI 1.05-1.18); birth weight > or = 3000 g (OR = 1.73; 95% CI 1.49-1.97); child follow-up in the private health-care network (OR = 1.10; 95% CI 1.02-1.18); and municipalities with four or five pro-breast-feeding measures (OR = 2.4; 95% CI 2.19-2.88). An analysis of the interactions between individual and contextual variables showed that the presence of at least four pro-breast-feeding measures in the municipality attenuated the risk of early termination of EBF associated with low maternal schooling and low birth weight, and transformed child follow-up in the public network into a protective factor against the early termination of breast-feeding. CONCLUSIONS: The presence of measures aimed at protecting, promoting and supporting breast-feeding in the municipality had a positive influence on EBF and attenuated the impact of risk factors for the termination of breast-feeding.  相似文献   
375.
The aim of this work was to study the effect of the prenylflavonoids xanthohumol, isoxanthohumol, and 8-prenylnaringenin on the activity and expression of the enzyme aromatase (estrogen synthase). The effect of different kinds of beer containing these prenylflavonoids was also tested. Aromatase activity was determined by measuring the release of tritiated water during the conversion of [(3)H]androstenedione to estrone. Aromatase expression was determined by RT-PCR. This assay was carried out in choriocarcinoma-derived JAR cells. The tested prenylflavonoids were able to inhibit estrogen formation, and their IC(50) values were determined, although no effect on aromatase expression was found. Lager beer, alcohol-free beer, stout beer, and xanthohumol-rich stout beer (200 microL/mL) significantly decreased aromatase activity. In conclusion, prenylflavonoids are able to modulate aromatase activity, decreasing estrogen synthesis, with relevance for the prevention and treatment of estrogen-dependent disorders such as breast cancer.  相似文献   
376.
This study aimed to evaluate the tolerance of common snook Centropomus undecimalis larvae and juveniles exposed to acute concentrations of un-ionized ammonia for 96 h at 35g L?1 salinity, after 24 h starvation. For that, 10 larvae (20.85 ± 1.46 mm) of 47 days post hatch (DPH) per experimental unit (1.5 L) were exposed to 0.00 ± 0.00, 0.65 ± 0.04, 1.29 ± 0.09, 2.59 ± 0.18, 3.88 ± 0.27, 5.17 ± 0.34, and 6.47 ± 0.43 mg L?1 NH3, in triplicates, at 26.72 ± 0.08°C, dissolved oxygen at 5.72 ± 0.10 mg L?1 and pH 8.45 ± 0.06. During this period, no mortalities were observed. Another trial was performed with five juveniles (20.35 ± 6.10 g, 13.90 ± 1.75 cm) per experimental unit (60 L) exposed to 0.00 ± 0.00, 2.26 ± 0.07, 2.68 ± 0.11, 3.20 ± 0.13, 3.68 ± 0.17, and 4.27 ± 0.16 mg L?1 NH3, in triplicates, at 21.90 ± 0.76°C, dissolved oxygen at 6.27 ± 0.21 mg L?1 and pH at 8.38 ± 0.04. Fish mortality increased as ammonia concentrations increased at each day, and LC50 96 h was 3.52 mg L?1 NH3. Larvae were less sensitive than juveniles, demonstrating that the environmental toxicity of ammonia to common snook is influenced by age. Sublethal exposition to ammonia caused histological damages in gills of common snook juveniles and variation on glucose levels, hematocrit, and red blood cells number, showing negative effects on fish homeostasis. Moreover, compared to other species, the common snook has great resistance to ammonia.  相似文献   
377.

Purpose

Cadmium has caused serious environmental problems due to its phytotoxicity, requiring solutions to reduce its concentration in the environment. Because S can alleviate the phytotoxicity caused by heavy metals, the evaluation of the effects of S supply is a promising approach to address this problem. The aim of this study was to determine the influence of S in reducing the phytotoxicity caused by Cd to Panicum maximum Jacq. cv. Tanzania (guinea grass) and to evaluate the potential of this grass for Cd phytoextraction.

Materials and methods

Tanzania guinea grass was cultivated in a nutrient solution to evaluate the combinations of five rates of S (0.1, 1.0, 1.9, 2.8, and 3.7 mmol L?1) and five rates of Cd (0.0, 0.5, 1.0, 1.5, and 2.0 mmol L?1), in a 52 fractional factorial design with six replications. Six plants were grown per pot in two growth periods to evaluate the effect of Cd on the establishment (51 days of age) and on the regrowth (18 days of growth) of the plants. During regrowth, Cd was not supplied in the nutrient solution. At the end of each growth period, growth parameters, concentrations of S and Cd, Cd transport factor, and concentrations of hydrogen peroxide (H2O2), malondialdehyde, reduced glutathione, and oxidized glutathione were evaluated.

Results and discussion

On the establishment of Tanzania guinea grass, application of Cd reduced mass production by 39 % due to the increases in the concentration of Cd (30 times compared with the treatment without Cd) and in lipid peroxidation (124 %). During regrowth, the residual effect of Cd resulted in a lower number of tillers (62 %) and leaves (89 %) caused by the increase in concentrations of Cd, H2O2 (49 %), and lipid peroxidation, which resulted in a 65 % lower dry mass production. The proper supply of S reduced concentration of Cd and tiller mortality rate due to the residual effect of Cd on the regrowth of the grass. Mass production by the roots was 43 % lower because of Cd, but the transport of Cd from roots to shoots increased. The increase in the concentration of glutathione (GSH) associated with a possible higher activity of antioxidant enzymes alleviated the phytotoxic effects of Cd on the guinea grass.

Conclusions

The supply of S reduces the phytotoxicity caused by Cd to guinea grass, especially during the regrowth of the plant, when the concentration of Cd is higher because of the transport from roots to shoots. Tanzania guinea grass showed to be very promising for phytoextraction of Cd due to its high mass production, even when Cd was largely available in the nutrient solution.
  相似文献   
378.
379.
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