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431.
Kato A Minoshima Y Yamamoto J Adachi I Watson AA Nash RJ 《Journal of agricultural and food chemistry》2008,56(17):8206-8211
Matricaria chamomilla L., known as "chamomile", has been used as an herbal tea or supplementary food all over the world. We investigated the effects of chamomile hot water extract and its major components on the prevention of hyperglycemia and the protection or improvement of diabetic complications in diabetes mellitus. Hot water extract, esculetin (3) and quercetin (7) have been found to show moderate inhibition of sucrase with IC50 values of 0.9 mg/mL and 72 and 71 microM, respectively. In a sucrose-loading test, the administration of esculetin (50 mg/kg body weight) fully suppressed hyperglycemia after 15 and 30 min, but the extract (500 mg/kg body weight) and quercetin (50 mg/kg body weight) were less effective. On the other hand, a long-term feed test (21 days) using a streptozotocin-induced rat diabetes model revealed that the same doses of extract and quercetin showed significant suppression of blood glucose levels. It was also found that these samples increased the liver glycogen levels. Moreover, chamomile extract showed potent inhibition against aldose reductase (ALR2), with an IC50 value of 16.9 microg/mL, and its components, umbelliferone (1), esculetin (3), luteolin (6), and quercetin (7), could significantly inhibit the accumulation of sorbitol in human erythrocytes. These results clearly suggested that daily consumption of chamomile tea with meals could contribute to the prevention of the progress of hyperglycemia and diabetic complications. 相似文献
432.
433.
Alison Gegios Rachel Amthor Busie Maziya-Dixon Chedozie Egesi Sally Mallowa Rhoda Nungo Simon Gichuki Ada Mbanaso Mark J. Manary 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(1):64-70
Cassava contains little zinc, iron, and β-carotene, yet it is the primary staple crop of over 250 million Africans. This study
used a 24-hour dietary recall to test the hypothesis that among healthy children aged 2–5 years in Nigeria and Kenya, cassava’s
contribution to the childrens’ daily diets is inversely related to intakes of zinc, iron, and vitamin A. Dietary and demographic
data and anthropometric measurements were collected from 449 Kenyan and 793 Nigerian children. Among Kenyan children 89% derived
at least 25% of their dietary energy from cassava, while among the Nigerian children 31% derived at least 25% of energy from
cassava. Spearman’s correlation coefficient between the fraction of dietary energy obtained from cassava and vitamin A intake
was r = −0.15, P < 0.0001, zinc intake was r = −0.11, P < 0.0001 and iron intake was r = −0.36, P < 0.0001. In Kenya, 59% of children consumed adequate vitamin A, 22% iron, and 31% zinc. In Nigeria, 17% of children had
adequate intake of vitamin A, 57% iron, and 41% zinc. Consumption of cassava is a risk factor for inadequate vitamin A, zinc
and/or iron intake. 相似文献
434.
Fragmentation of China’s landscape by roads and urban areas 总被引:1,自引:0,他引:1
Taian Li Fraser Shilling James Thorne Fengmin Li Heidi Schott Ryan Boynton Alison M. Berry 《Landscape Ecology》2010,25(6):839-853
China’s major paved road-ways (national roads, provincial roads, and county roads), railways and urban development are rapidly
expanding. A likely consequence of this fast-paced growth is landscape fragmentation and disruption of ecological flows. In
order to provide ecological information to infrastructure planners and environmental managers for use in landscape conservation,
land-division from development must be measured. We used the effective-mesh-size (Meff) method to provide the first evaluation of the degree of landscape division in China, caused by paved roads, railways, and
urban areas. Using Meff, we found that fragmentation by major transportation systems and urban areas in China varied widely, from the least-impacted
west to the most impacted south and east of China. Almost all eastern provinces and counties, especially areas near big cities,
have high levels of fragmentation. Several eastern-Chinese provinces and biogeographic regions have among the most severe
landscape fragmentation in the world, while others are comparable to the least-developed areas of Europe and California. Threatened
plant hotspots and areas with high mammal species diversity occurred in both highly fragmented and less fragmented areas,
though future road development threatens already moderately divided landscapes. To conserve threatened biodiversity and landscapes,
we recommend that national and regional planners in China consider existing land division before making decisions about further
road development and improvement. 相似文献
435.
Clive A. McAlpine Leonie M. Seabrook Jonathan R. Rhodes Martine Maron Carl Smith Michiala E. Bowen Sarah A. Butler Owen Powell Justin G. Ryan Christine T. Fyfe Christine Adams-Hosking Andrew Smith Oliver Robertson Alison Howes Lorenzo Cattarino 《Landscape Ecology》2010,25(8):1155-1168
The need to avert unacceptable and irreversible environmental change is the most urgent challenge facing society. Landscape ecology has the capacity to help address these challenges by providing spatially-explicit solutions to landscape sustainability problems. However, despite a large body of research, the real impact of landscape ecology on sustainable landscape management and planning is still limited. In this paper, we first outline a typology of landscape sustainability problems which serves to guide landscape ecologists in the problem-solving process. We then outline a formal problem-solving approach, whereby landscape ecologists can better bring about disciplinary integration, a consideration of multiple landscape functions over long time scales, and a focus on decision making. This framework explicitly considers multiple ecological objectives and socio-economic constraints, the spatial allocation of scarce resources to address these objectives, and the timing of the implementation of management actions. It aims to make explicit the problem-solving objectives, management options and the system understanding required to make sustainable landscape planning decisions. We propose that by adopting a more problem-solving approach, landscape ecologists can make a significant contribution towards realising sustainable future landscapes. 相似文献
436.
Roy Kennedy Alison J. Wakeham 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(1):147-155
A monoclonal antibody that recognises components of the wall of sporangia of Peronospora destructor was raised. Tests using spores of higher fungi and other species of mildew demonstrated the specificity of the monoclonal.
The antibody was used to develop lateral flow devices for sporangia of P. destructor. A competitive lateral flow format was developed which could detect onion downy mildew sporangia. Five-microliter gold anti-mouse
IgM solution pre-mixed with 10 μl of P. destructor monoclonal antibody (EMA 242) proved the optimal concentration for detection of sporangia of P. destructor when applied to sample pads of lateral flow devices. Limits of approximately 500 sporangia of P. destructor could be detected by the absence of a test line on the lateral flow device within test samples. Using a scanning densitometer
improved the sensitivity of detection. Further development and validation of the test is required if it is to be used for
risk assessments of onion downy mildew in the field. 相似文献
437.
Mariann Rakszegi Mark D. Wilkinson Paola Tosi Alison Lovegrove Geza Kovacs Zoltan Bedo Peter R. Shewry 《Journal of Cereal Science》2009
Six tetraploid (5 Triticum turgidum and 1 Triticum timopheevii) and four hexaploid (three Triticum aestivum and one Triticum kiharae) taxa of Triticum were studied in order to identify novel variation in Pin genes and proteins which can be exploited in the improvement of cultivated wheat. Western blotting with a highly specific antibody showed that puroindoline proteins were present in all of the hexaploid lines but were absent from the tetraploids. The immunoreactive bands differed slightly in their relative mobilities and their relative amounts, which could have resulted from variation in the allelic forms of Pin a and Pin b. This was supported by HPLC analyses which showed differences in the retention times and peaks heights of the putative puroindoline components in T. kiharae and T. timopheevii. Sequence analyses of cDNAs also showed variation in the sequences of expressed puroindoline genes. In particular, a sequence encoding a new form of Pin b was present in T. aestivum ssp. macha. 相似文献
438.
Alison Matthews 《The Forestry Chronicle》2018,29(3):357-365
439.
A one-stage analysis of a series of variety trials involves a combined analysis of the individual plot data across trials. Together with prudent modelling of the genetic effects across trials, this is considered to be the gold standard analysis of multi-environment field trial data. An alternative is a two-stage approach in which the variety means from an analysis of the individual trials in stage one are combined into a weighted mixed model analysis in stage two to give the full set of predicted variety by environment effects and an estimate of their associated variance structure. The two-stage analysis will exactly reproduce the one-stage analysis if the full variance-covariance matrix of the means from stage one is known and is utilised in stage two. Typically the full matrix is not stored and a diagonal approximation is used. This introduces a compromise to the full analysis. The impacts of a diagonal approximation are greater in the presence of sophisticated models for the genetic effects. A second compromise is through a loss of information in estimating the non-genetic variance parameters using the two-stage approach. In this paper we draw a direct link between the one and two-stage analysis approaches for crop variety evaluation data in Australia. We now have the computing power to analyse large and complex multi-environment variety trial data sets using the one-stage approach without the need for a two-stage approximation. This should motivate a move away from the two-stage approach in a range of contexts. 相似文献
440.