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81.
Rios LY Bennett RN Lazarus SA Rémésy C Scalbert A Williamson G 《The American journal of clinical nutrition》2002,76(5):1106-1110
BACKGROUND: Polyphenolic procyanidins are abundant flavonoid polymers in Western diets. In vitro biological activity has been reported for these compounds, but activity in vivo depends on the amount and chemical nature of the flavonoids reaching the gastrointestinal tract. Degradation of procyanidins under simulated gastric conditions at pH 2.0 has been reported in vitro. OBJECTIVE: The objective was to examine whether depolymerization of procyanidins occurs in the stomach of human subjects in vivo. DESIGN: After an overnight fast, 6 healthy subjects (3 men and 3 women) consumed 500 mL of a cocoa beverage containing 733 mg procyanidin polymers and 351 mg structurally related flavanol monomers. With the use of a nasogastric tube, stomach contents were collected every 10 min after beverage ingestion until the stomach was emptied. Flavanols and procyanidins (up to pentamers) were quantified by normal and reversed-phase HPLC. RESULTS: In all subjects, gastric transit lasted approximately 50-60 min. No change in the HPLC profile of procyanidins was observed during this period, showing that procyanidins were remarkably stable in the stomach environment. CONCLUSION: The results suggest that most ingested procyanidins reach the small intestine intact and are available for absorption or metabolism. 相似文献
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83.
Diffusion-weighted imaging of patients with subacute cerebral ischemia: comparison with conventional and contrast-enhanced MR imaging 总被引:12,自引:0,他引:12
Augustin M Bammer R Simbrunner J Stollberger R Hartung HP Fazekas F 《AJNR. American journal of neuroradiology》2000,21(9):1596-1602
BACKGROUND AND PURPOSE: The importance of diffusion-weighted imaging (DWI) for delineating acute ischemic lesions has been investigated extensively; however, few studies have investigated the role of DWI in the subacute stage of stroke. Because these lesions tend to appear bright throughout the first days of ischemia, owing to restricted diffusion, we speculated that DWI could also improve the detection of subacute infarcts as compared with conventional and contrast-enhanced MR imaging. METHODS: Interleaved echo-planar DWI with phase navigation was performed on a 1.5-T MR unit in a consecutive series of 53 patients (mean age, 66 +/- 14 years) with suspected recent cerebral ischemia. The interval between onset of clinical symptoms and MR imaging ranged from 1 to 14 days (mean, 6 +/- 4 days). Contrast material was given to 28 patients in a dose of 0.1 mmol/kg. RESULTS: DWI clearly delineated recent ischemic damage in 39 patients (74%) as compared with 33 (62%) in whom lesions were identified or suspected on conventional T2-weighted images. DWI provided information not accessible with T2-weighted imaging in 17 patients when evidence of lesion multiplicity or detection of clinically unrelated recent lesions was included for comparison. Subacute ischemic lesions were also seen more frequently on DWI sequences than on contrast-enhanced images (20 versus 13 patients). DWI was more likely to make a diagnostic contribution in the first week of stroke and in patients with small lesions or preexisting ischemic cerebral damage than was conventional MR imaging. CONCLUSION: Recent ischemic damage is better shown on DWI sequences than on conventional and contrast-enhanced MR images throughout the first days after stroke and may provide further information about the origin of clinical symptoms. Adding DWI to imaging protocols for patients with subacute cerebral ischemia is recommended. 相似文献
84.
85.
We saw three patients working in the production of polyurethanes, who showed mydriasis and cycloplegia of unknown origin. In one patient there was also a transient opacification of corneal stroma. After discontinuation of working both mydriasis and cycloplegia resolved completely within 3-5 days. Because of the history and the analysis of chemical reactions involved in the production of polyurethanes there is strong evidence that both mydriasis and cycloplegia have been caused by topical and (/or) systemic intoxication with the aryl diet of the isocyanate molecule. 相似文献
86.
Vincent J. D'Souza Ted A. Glass Guillermo Velasquez Augustin G. Formanek 《Cardiovascular and interventional radiology》1984,7(5):229-231
Renal artery aneurysms are an unusual cause of renovascular hypertension in children. When present in an intrarenal location,
they pose a difficult surgical problem and transcatheter embolization may represent an effective alternative treatment. 相似文献
87.
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89.
Lafay S Gueux E Rayssiguier Y Mazur A Rémésy C Scalbert A 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》2005,75(2):119-125
The effects of caffeic acid, a major phenolic compound of the diet, on oxidative stress and cholesterolemia are studied in rats submitted to oxidative stress by iron overload. Male Wistar rats were fed semi-synthetic diets containing regular (50 mg/kg diet) or high (2000 mg/kg) doses of iron with and without caffeic acid (6460 mg/kg) for 4 weeks. The high doses of iron induced an increase of lipid oxidation in the liver, as measured by thiobarbituric acid-reactive substances (TBARS), and an increase of cholesterolemia. Caffeic acid fully prevented the pro-oxidant effects of high iron doses (p < 0.001). It also reduced lipid peroxidation in rats fed the low iron dose (p < 0.05). Caffeic acid also increased vitamin E levels in plasma (2.74 micromol/L to 4.09 micromol/L for normal diet; p < 0.001; 2.78 micromol/L to 4.94 micromol/L for iron supplemented diet p < 0.001). Iron-induced hypercholesterolemia was inhibited by caffeic acid (1.07 g/L to 0.82 g/L; p < 0.001). These results demonstrate the antioxidative capacity of caffeic acid, a highly bioavailable polyphenol, in an in vivo model of oxidative stress. 相似文献
90.
Polyphenol levels in human urine after intake of six different polyphenol-rich beverages 总被引:1,自引:0,他引:1
Ito H Gonthier MP Manach C Morand C Mennen L Rémésy C Scalbert A 《The British journal of nutrition》2005,94(4):500-509
Dietary polyphenols are suggested to participate in the prevention of CVD and cancer. It is essential for epidemiological studies to be able to compare intake of the main dietary polyphenols in populations. The present paper describes a fast method suitable for the analysis of polyphenols in urine, selected as potential biomarkers of intake. This method is applied to the estimation of polyphenol recovery after ingestion of six different polyphenol-rich beverages. Fifteen polyphenols including mammalian lignans (enterodiol and enterolactone), several phenolic acids (chlorogenic, caffeic, m-coumaric, gallic, and 4-O-methylgallic acids), phloretin and various flavonoids (catechin, epicatechin, quercetin, isorhamnetin, kaempferol, hesperetin, and naringenin) were simultaneously quantified in human urine by HPLC coupled with electrospray ionisation mass-MS (HPLC-electrospray-tandem mass spectrometry) with a run time of 6 min per sample. The method has been validated with regard to linearity, precision, and accuracy in intra- and inter-day assays. It was applied to urine samples collected from nine volunteers in the 24 h following consumption of either green tea, a grape-skin extract, cocoa beverage, coffee, grapefruit juice or orange juice. Levels of urinary excretion suggest that chlorogenic acid, gallic acid, epicatechin, naringenin or hesperetin could be used as specific biomarkers to evaluate the consumption of coffee, wine, tea or cocoa, and citrus juices respectively. 相似文献