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991.
OBJECTIVES: To assess the intake inadequacy and food sources of zinc of people in China. DESIGN AND SUBJECTS: Diets of 68 962 subjects aged 2-101 years (urban 21 103, rural 47,859) in the 2002 China National Nutrition and Health Survey were analysed. Dietary intake was assessed using 24-hour recall for three consecutive days. Zinc intake inadequacy was calculated based on values suggested by the World Health Organization. RESULTS: The median zinc intake ranged from 4.9 mg day- 1 (urban girls, 2-3 years) to 11.9 mg day-1 (rural males, 19+ years). The zinc density of urban residents (2-3 to 19+ years) was 5.0-5.3 mg day-1 (1000 kcal)-1, significantly higher than that of their rural counterparts (4.7-4.8 mg day-1 (1000 kcal)-1). Differences in food sources of zinc from cereal grains (27.4-45.1 vs. 51.6-63.2%) and animal foods (28.4-54.8 vs. 16.8-30.6%) were found between urban and rural residents. Zinc from vegetables and fruits (8.2-13.8 vs. 9.7-12.4%) and legumes (1.3-3.3 vs. 2.5-3.4%) was comparable between urban and rural residents. The proportion of zinc intake inadequacy ranged between 2.8% (urban females, 19+ years) and 29.4% (rural lactating women). Rural residents had higher proportions of zinc intake inadequacy than their urban counterparts. Significantly higher proportions of zinc inadequacy were found in the category of phytate/zinc molar ratio >15 for both rural and urban residents. CONCLUSIONS: About 20% of rural children are at risk of inadequate zinc intake, with phytate as a potential important inhibitor. Moreover, lactating women are also considered a vulnerable group. 相似文献
992.
Jeroen Peters Wojciech Sledz Jan H. W. Bergervoet Jan M. van der Wolf 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(2):97-107
An enrichment microsphere immunoassay (MIA) was developed, based on the Luminex xMAP® technology, for the simultaneous (duplex) detection of Pectobacterium atrosepticum (former name Erwinia carotovora subsp. atroseptica) (Pca) and Dickeya dianthicola (former name Erwinia chrysanthemi) (Dcd) in potato plant extracts. Target bacteria in the extracts were enriched for 48 h in a semi-selective broth containing polypectate under low oxygen conditions. Samples were subsequently incubated with antibody-coated colour-coded microspheres (beads) and with secondary antibodies conjugated with Alexa Fluor® 532, a reporter dye. Samples were analyzed with the Luminex analyzer, in which one laser identified each microsphere and another laser the reporter dye conjugated to the secondary antibodies. The assay required minimal sample preparation, could be completed in 1 h, was performed in 96 wells microtitreplates and required no wash steps. The limit of detection for the duplex enrichment MIA was 100–1000 cfu ml?1, which was a hundred times lower than of an enrichment-ELISA. Without enrichment, the sensitivity of MIA and ELISA was largely similar and ranged between 106 and 107 cells ml?1. No difference in sensitivity was found between a MIA in a single or duplex format. In a comparative test with non-infected potato plant extracts and extracts from plants infected with Pca or Dcd, results of the enrichment MIA correlated well with those of the enrichment ELISA and enrichment PCR. These results indicate that MIA can be reliably used for multiplex detection of soft rot Enterbacteriaceae in crude potato plant extracts. The technology is an attractive and cost-effective alternative to other detection methods, including ELISA. 相似文献
993.
In terrestrial ecosystems, gross nitrogen mineralisation is positively correlated to microbial biomass but negatively to soil
organic matter C-to-N ratios; the influence of the microbial community structure is less well known. Here, we relate rates
of gross N mineralisation to fungi-to-bacteria ratios in three natural forest types of contrasting N availability and in a
long-term N-loading experiment in a boreal forest. We report, for the first time, a strong negative correlation between gross
N mineralisation and the fungi-to-bacteria ratio ( = 0.91, P = 0.0005, N = 7). There was also a negative correlation between gross N mineralisation and the C-to-N ratio ( = 0.89, P = 0.001, N = 7), but a weaker positive correlation between gross N mineralisation and soil pH ( = 0.64, P = 0.019, N = 7). Our analysis suggests that soil fungi-to-bacteria and C-to-N ratios are interrelated and that they exert strong influences
on soil N cycling in boreal forests. 相似文献
994.
Eirini I Rigopoulou Maria Mytilinaiou Ourania Romanidou Christos Liaskos George N Dalekos 《Journal of Autoimmune Diseases》2007,4(1):2
Background
Non-organ specific autoantibodies are highly prevalent in patients with chronic hepatitis C (HCV). Among them, anti-liver kidney microsomal type 1 (LKM1) antibody – the serological marker of type 2 autoimmune hepatitis (AIH-2)- is detected in up to 11% of the HCV-infected subjects. On the other hand, anti-liver cytosol type 1 antibodies (anti-LC1) – either in association with anti-LKM1, or in isolation- and anti-soluble liver antigen antibodies (anti-SLA) have been considered as useful and specific diagnostic markers for AIH. However, their specificity for AIH has been questioned by some recent studies, which have shown the detection of anti-LC1 and anti-SLA by immunoprecipitation assays in HCV patients irrespective of their anti-LKM1 status. The aim of the present study was to test the anti-LC1 and anti-SLA presence by specific enzyme linked immunosorbent assays (ELISAs), in a large group of Greek HCV-infected patients with or without anti-LKM1 reactivity as firstly, immunoprecipitation assays are limited to few specialized laboratories worldwide and cannot be used routinely and secondly, to assess whether application of such tests has any relevance in the context of patients with viral hepatitis since antibody detection based on such ELISAs has not been described in detail in large groups of HCV patients.Methods
One hundred and thirty eight consecutive HCV patients (120 anti-LKM1 negative and 18 anti-LKM1 positive) were investigated for the presence of anti-LC1 and anti-SLA by commercial ELISAs. A similar number (120) of chronic hepatitis B virus (HBV) infected patients seronegative for anti-LKM1 was also tested as pathological controls.Results
Six out of 18 (33%) anti-LKMpos/HCVpos patients tested positive for anti-LC1 compared to 1/120 (0.83%) anti-LKMneg/HCVpos patients and 0/120 (0%) of the anti-LKM1neg/HBVpos patients (p < 0.001 for both comparisons). Anti-SLA antibodies were not present in any of the HCV (with or without anti-LKM1) or HBV-infected patients.Conclusion
We showed that anti-LC1 and anti-SLA autoantibodies are not detected by conventional assays in a large group of anti-LKM1 negative patients with chronic hepatitis B and C infections. Based on these results we cannot find any justification for the application of anti-LC1 and anti-SLA tests in the routine laboratory testing of viral hepatitis-related autoantibody serology with the only potential exception being the anti-LC1 screening in anti-LKM1pos/HCVpos patients.995.
Effect of fibers on the flow property of turbulent fiber suspensions in a contraction 总被引:1,自引:0,他引:1
In the flow of turbulent fiber suspensions flowing through a contraction with rectangular cross-section, the Reynolds averaged
Navier-Stokes equation with the term of additional stress resulting from fibers was solved with the Reynolds stress model
to get distributions of the mean velocity, mean pressure, turbulent kinetic energy and turbulent dissipation. It is found
that the mean velocities at exit are small around the center and large near the wall for higher concentration. Fibers reduce
turbulent intensity and turbulent dissipation at central line, but enhance them over the cross section at exit. Fibers have
no effect of restraint on the turbulence in the contraction flow. The additional stress resulting from fibers plays a role
in the increase of drag. 相似文献
996.
Reto M Figueira ME Filipe HM Almeida CM 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(4):139-144
To evaluate the potential benefits and risks associated with tea consumption it is important to identify the constituents
of this beverage. Levels of some minerals, caffeine and catechins in green tea samples commercialized in Portugal were evaluated.
Potassium is the metal present in larger amount (92–151 mg/l). The content of sodium, calcium, fluoride, aluminium, manganese
and iron were 35–69, 1.9–3.5, 0.80–2.0, 1.0–2.2, 0.52–1.9, 0.020–0.128 mg/l, respectively. Chromium and selenium were not
detected. The resulting data showed considerable variability in catechins content. The levels of epigallocatechin gallate
(EGCG) ranged from 117 to 442 mg/l, epicatechin 3-gallate (EGC) from 203 to 471 mg/l, epigallocatechin (ECG) from 16.9 to
150 mg/l, epicatechin (EC) from 25 to 81 mg/l and catechin (C) from 9.03 to 115 mg/l. Caffeine contents in the green tea infusions
studied were between 141–338 mg/l. Green tea infusions provide significant amounts of catechins and could be an important
source of some minerals. 相似文献
997.
Zheng J He J Ji B Li Y Zhang X 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(1):7-11
The root of Platycodon grandiflorum (Jacq.) A. DC has been reported to have a wide range of health benefits in oriental food. This study examined the hypoglycemic
effects of Platycodon grandiflorum (Jacq.) A. DC aqueous-ethanol extract (PGE) in streptozotocin (STZ) -induced diabetic ICR mice (STZ diabetic mice) for the
first time. The effects of PGE on blood glucose, plasma insulin levels and body weight were investigated. A significant decrease
in blood glucose levels was observed after single administration of PGE. Furthermore, Glibenclamide and PGE significantly
suppressed the rise in blood glucose after 30 min in the acute glucose tolerance test. Treatment with glibenclamide and PGE
resulted in a reduction in blood glucose levels from the 2nd week, and this reduction was maintained until the 4th week of
treatment. The body weight changed slightly in glibenclamide and PGE treated mice in comparison with the STZ control group.
Plasma insulin levels were increased with glibenclamide treatment in STZ diabetic mice, whereas such effect was not observed
with PGE. These results indicated that PGE could induce hypoglycemic effects without stimulating insulin secretion. 相似文献
998.
Bryszewska MA Ambroziak W Langford NJ Baxter MJ Colyer A Lewis DJ 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(3):121-126
The potential of selenium-enriched rye/wheat sourdough bread as a route for supplementing dietary selenium intakes is reported.
In addition to their normal diets, 24 female volunteers (24 to 25 years old) were fed either selenium-enriched bread or non-enriched
bread each day (68.02 and 0.84 μg selenium day−1 respectively) for 4 weeks. The chemical form of the selenium in the bread had been characterised using HPLC-ICP-MS, which
showed that 42% of the extractable selenium was present as selenomethionine. Plasma selenium levels and plasma platelet glutathione
peroxidase (GPx1) activity were measured in the volunteers’ blood over a 6-week period. A statistically significant difference
(p = 0.001) was observed in the mean percentage change data, calculated from the plasma selenium level measurements for the
enriched and control group, over the duration of the study. A comparable difference was not observed for the platelet GPx1
activity (p = 0.756), over the same period. Two weeks after cessation of the feeding stage, i.e., at t = 6 weeks, the mean percentage change value for the selenium plasma levels in the enriched group was still significantly
elevated, suggesting that the absorbed selenium had been incorporated into the body’s selenium reserves, and was then being
slowly released back into the volunteers’ blood. 相似文献
999.
Sotelo A López-García S Basurto-Peña F 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(3):133-138
Nutrient and antinutritional/toxic factors present in some edible flowers consumed in Mexico were determined. The edible flowers
were: Agave salmiana, Aloe vera, Arbutus xalapensis, Cucurbita pepo (cultivated), Erythrina americana, Erythrina caribaea, Euphorbia radians benth and Yucca filifera. The nutrient content in the flowers studied is similar to that of the edible leaves and flowers studied mainly in Africa.
The moisture content of the flowers varied from 860 to 932 g kg−1. Crude protein (CP) was between 113 to 275 g kg−1 DM, crude fiber, 104 to 177 g kg−1 DM and the nitrogen free extract, between 425 to 667 g kg−1 DM. The highest chemical score (CS) was found in E. americana and A. salmiana; in five samples the limiting amino acid was lysine, and in three of them it was tryptophan. Trypsin inhibitors and hemaglutinnins
had a very low concentration. Alkaloids were present in both the Erythrina species and the saponins in A. salmiana and Y. filifera. Cyanogenic glucosides were not found in the studied flowers. The traditional process of preparing these specific flowers
before consumption is by cooking them and discarding the broth; in this way the toxic substances are diminished or eliminated.
These edible flowers from wild plants consumed in local areas of the country play an important role in the diet of the people
at least during the short time of the season where they are blooming. 相似文献
1000.