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The effect of wild blueberry (Vaccinium angustifolium) consumption on postprandial serum antioxidant status in human subjects 总被引:2,自引:0,他引:2
The aim of the present study was to determine whether the consumption of wild blueberries (Vaccinium angustifolium), a concentrated source of non-nutritive antioxidant phytochemicals, would enhance postprandial serum antioxidant status in healthy human subjects. A single-blinded crossover study was performed in a group of eight middle-aged male subjects (38-54 years). Subjects consumed a high-fat meal and a control supplement followed 1 week later by the same high-fat meal supplemented with 100.0 g freeze-dried wild blueberry powder. Upon brachial vein catheterization, fasting and postprandial serum samples were taken sequentially and analysed for lipids and glucose and for serum antioxidant status. Serum antioxidant status was determined using the oxygen radical absorbance capacity (ORAC) assay and the total antioxidant status (TAS) assay. The wild-blueberry treatment was associated with a significant treatment effect as determined by the ORAC assay (water-soluble fraction ORAC(perchloric acid (PCA)), P=0.04). Significant increases in serum antioxidant status above the controls were observed at 1 h (ORAC(PCA) (8.5 % greater), P=0.02; TAS (4.5 % greater), P=0.05), and 4 h (ORAC(total) (15.0 % greater), P=0.009; ORAC(acetone) (16.0 % greater), P=0.007) post-consumption of the high-fat meal. In conclusion, the consumption of wild blueberries, a food source with high in vitro antioxidant properties, is associated with a diet-induced increase in ex vivo serum antioxidant status. It has been suggested that increasing the antioxidant status of serum may result in the reduced risk of many chronic degenerative diseases. 相似文献
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Cocaine use in pregnancy in Amsterdam 总被引:1,自引:0,他引:1
BJ Smit K Boer AM van Huis ISE Lie-A-Ling SC Schmidt 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S404):32-35
To study the effects of cocaine use in pregnancy in Amsterdam, clinical data on cocaine-using pregnant women ( n = 21) and their offspring ( n = 23) were obtained retrospectively (1987–1994) at the Academic Medical Center, Amsterdam. Infants exposed to cocaine had a median gestational age of 39 weeks and a median birth weight of 3090 g. There were six preterm infants, two small-for-gestational-age infants and five infants with a small head circumference. Three infants had a congenital malformation. One infant (Potter's syndrome) died shortly before birth. One infant had congenital syphilis, four had intracerebral abnormalities on ultrasound and four had abnormal neurologic symptoms in the neonatal period. One infant died after 21 days of life. At follow-up four infants showed abnormal development. In 12 of the 23 infants (52%), one or more possible effects of cocaine were found. 相似文献
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Male and female rats were fed a semipurified diet containing either 0,2 or 25 ppm diazinon for varying times. At appropriate times, animals were bled from the orbital sinus to facilitate measurement of plasma cholinesterase and erythrocyte acetylcholinesterase activities. Additional animals were sacrificed to enable determination of brain acetylcholinesterase activity. General nutritional evaluations included measurement of body weight gains and feed consumption during the growing period. Feeding diazinon at the levels employed produced no visible toxic manifestations. Body weight gains and feed consumption were comparable among control and treated groups during all studies. Feeding 25 ppm diazinon for 30 days produced more significant reduction of cholinesterase activity in plasma (by 22–30%) and brain (by 5–9%) among treated females compared to corresponding males. Erythrocyte acetylcholinesterase activity was significantly more depressed (by 13–17%) in treated females relative to appropriate males at Days 21–28 of the feeding trial. At no time was cholinesterase activity in any tissue assayed more significantly reduced among treated males than females. Feeding 2 ppm diazinon for 7 days failed to modify erythrocyte acetylcholinesterase activity among both sexes relative to controls. Plasma cholinesterase activities of treated males were not significantly different from control values, whereas, treated females showed significant depression (by 29%) of plasma enzyme activity. This latter finding is of interest since 2 ppm is the “no effect” level of diazinon for the rat established by the FAO/WHO on the basis of studies which focused on the male sex. The results indicate the female rat to be more sensitive to the toxicity of dietary diazinon compared to the male. 相似文献