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排序方式: 共有1034条查询结果,搜索用时 15 毫秒
51.
52.
Diabetes and hypertension increases in a society with abdominal obesity: results of the Mexican National Health Survey 2000 总被引:5,自引:0,他引:5
Sánchez-Castillo CP Velásquez-Monroy O Lara-Esqueda A Berber A Sepulveda J Tapia-Conyer R James WP 《Public health nutrition》2005,8(1):53-60
OBJECTIVES: To determine the prevalences of overweight, obesity, type 2 diabetes mellitus (DM) and hypertension (HT) in the Mexican population and compare them with those of a previous Mexican urban survey and an American survey. DESIGN: A structured, randomised, nationally representative Mexican sample was compared with a 1993 Mexican urban survey and the US Third National Health and Nutrition Examination Survey (NHANES III) of non-Hispanic Whites. SETTING: The Mexican National Health Survey 2000.Subjects: Subjects were 12,856 men and 28,332 women, aged 20-69 years, who had their body weight, height, waist circumference (WC), blood pressure and fasting capillary blood glucose measured. RESULTS: Mexican adult men and women had a high prevalence of overweight (41.3 and 36.3%, respectively) and obesity (19.4 and 29.0%, respectively), similar to those in the USA in 1988-1992 and exceeding those of the 1993 Mexican survey. The prevalence of HT was 33.3% in men and 25.6% in women, with inferred DM rates of 5.6 and 9.7%, respectively. Abdominal obesity affected 46.3% of men (WC>or=94 cm) and 81.4% of women (WC>or=80 cm). There was a high prevalence of abdominal obesity in normal-weight women, with co-morbidities relating better to WC than to body mass index (BMI) in both sexes. Rates of DM and HT exceeded US rates on a comparable BMI or WC basis in adults aged <50 years. CONCLUSION: The high prevalence of obesity and abdominal obesity in Mexicans is associated with markedly increased prevalences of DM and HT to levels comparable with, or even higher than, those in NHANES III of non-Hispanic Whites. 相似文献
53.
Magni C Herndl A Sironi E Scarafoni A Ballabio C Restani P Bernardini R Novembre E Vierucci A Duranti M 《Journal of agricultural and food chemistry》2005,53(11):4567-4571
The prevalence of food allergies in the world population requires integrated approaches to identify new potential allergens, especially those of plant origin. The aim of this work was the allergen in vitro analysis of Lupinus albus seed proteome, a promising food protein source, and the assessment of IgE cross-reactivities with other more diffused legume species. A combination of one- and two-dimensional gel electrophoresis and immunoblotting analyses with specific IgGs for band identification and lupin-sensitized patients' circulating IgEs for allergenicity studies has been used. Two lupin proteins, namely, conglutin gamma and 11S globulin basic subunits, strongly reacted with all patients' sera. Also, cross-reactivities with the homologous polypeptides of other legume species were observed. Otherwise, no reaction at all was detected with a 2S-type lupin protein. This global electrophoretic approach has allowed the identification of a new potential lupin allergen and confirmed the cross-reactivity among the legume 11S globulin basic subunits. 相似文献
54.
Multiple effects of urbanization on the biodiversity of developing countries: The case of a fast-growing metropolitan area (Concepción, Chile) 总被引:1,自引:0,他引:1
Urbanization is increasingly homogenizing the biota of less developed countries. Even though urban sprawl is a worldwide problem, most studies on the effects of urbanization, and the conceptual models have focused on developed countries. South America has not escaped urbanization, and here we discuss the potential impacts of urban sprawl with respect to three ecosystems in the metropolitan area of Concepción, Chile. We consider this area a good model and fairly representative of other cities in developing countries which are also experiencing rapid and uncontrolled growth. We found that the impacts of urban sprawl on biodiversity in the metropolitan area of Concepción differ little from cities in other parts of the world: native ecosystems are replaced by pavements and buildings and what is left of the natural soil is covered with green areas dominated by non-native ornamental species. Wetlands and other peri-urban ecosystems are rapidly being destroyed, fragmented or invaded by non-native species. We found that from a study area of 32,000 ha, there was a net loss to urbanization of 1734 ha of wetlands (23% of the original) and 1417 ha (9%) of agricultural, forest and shrub land cover types between 1975 and 2000. From the total area urbanized (3151 ha), 55% corresponded to wetlands and 45% to agricultural, forest and shrub lands cover types. We see the lack of environmental awareness as a major cause of the increasing deterioration of biodiversity in urban areas of developing countries. More research is needed to fully understand the effects of urban sprawl on the biodiversity of developing countries to include these ecosystems in global conservation strategies. 相似文献
55.
Pagliuca G Gazzotti T Zironi E Serrazanetti GP Mollica D Rosmini R 《Journal of agricultural and food chemistry》2003,51(17):5111-5115
High-performance liquid chromatography with fluorescence detection was used for the analysis of polycyclic aromatic hydrocarbons (PAHs), in "Diavoletto" smoked cheese. Such cheese is typically produced in the Sorrento peninsula, and it is smoked commonly with different materials of vegetable origin. The importance of the smoking generation material is proven by the attention that the EU is paying in indicating the list of wood that may be used to produce smoking flavor agents. The PAHs considered are classified as "probable human carcinogens" by the U.S. Environmental Protection Agency for sufficient data from animal bioassays. The smoked samples contained high molecular mass PAHs with different levels ranging from 0.12 to 6.21 microg/kg. The determination was carried out also on liquid smoking flavor agents, smoke-flavored cheese, and nonsmoked cheese to measure the level of contamination before the treatment. 相似文献
56.
Rosanna S. Valitutto Silvia M. Sella Emmanoel V. Silva-Filho Roberto Guimarães Pereira Norbert Miekeley 《Water, air, and soil pollution》2007,178(1-4):89-102
Aquatic macrophytes are well known accumulators for heavy metals, the reason why they are used as bioindicators for water quality and in phytoremediaton strategies. This study reports on the elemental concentrations in four free-floating aquatic macrophytes (S. auriculata; P. stratiotes; E. crassipes and E. azurea) growing in two water reservoirs (Santana e Vigário, Rio de Janeiro State, Brazil) of an electric power plant that receive input from the polluted Paraíba do Sul River. Filtered water samples and water suspended solids from these environments were also analysed. Inductively coupled plasma mass spectrometry was used as the principal method, allowing the determination of up to 41 elements, including the rare-earth elements (REEs) and other trace metals not assayed before in these macrophytes. The results show that all elements studied are accumulated by the macrophytes with concentration ratios (CR = [plant]: [water]) varying from about 1,000 to 200,000, based on the dry weight of the plant species. With a few exceptions, highest accumulations were observed in E. crassipes in which CRs increase in the sequence: Cu < Mo < Cr < Pb < Tl < Fe < La < Zn < Ce< Mn. Surprisingly high CRs (e.g. Ce: 74,000) and corresponding mass concentrations were observed for the rare-earth elements (e.g. ∑REE: 112 mg kg?1), also measured in the water suspended particle fraction. The results show that this fraction acts as an effective sink for trace metals in the aquatic system studied and seems to play also an important role in the transfer of metals from water to the plant species. 相似文献
57.
Deriving river networks and catchments at the European scale from medium resolution digital elevation data 总被引:2,自引:0,他引:2
Roberto Colombo Jürgen V. Vogt Pierre Soille Maria L. Paracchini Alfred de Jager 《CATENA》2007,70(3):296-305
The extraction of drainage networks and catchment boundaries from digital elevation models (DEMs) has received considerable attention in recent years and is recognized as a viable alternative to traditional surveys and the manual evaluation of topographic maps. However, most studies have covered limited areas due to the lack of detailed information and/or the lack of highly efficient algorithms. In this paper we present an application that delineates river networks and catchment boundaries across the European continent from a medium resolution (250 m) DEM. We exploit novel algorithms based on the concepts of mathematical morphology and implement a landscape stratification for drainage density.A flow direction grid is computed using an efficient algorithm for the removal of spurious pits. River networks are then derived by imposing a variable threshold for the minimum contributing area needed to form and maintain a channel. This is achieved through a landscape stratification that reflects the ability of the terrain to develop different drainage densities. It is shown that the analysis of environmental characteristics coupled with the analysis of local slope versus contributing area enables river network mapping with a spatially varying drainage density. The result has been validated by comparing the derived data to digital river and catchment data from other sources and with varying scales of observation. 相似文献
58.
59.
Lead and its isotope ratios (IRs) in 83 Italian wines from 42 different administrative provinces produced on laboratory scale in 2000 were measured by inductively coupled plasma mass spectrometry. Lead had a median of 19.0 microg/L, ranging from 10.0 up to 149 microg/L and was higher in the samples from northwestern Italy. The values of the IRs were (mean +/- standard deviation) 1.171 +/- 0.011 for (206)Pb/(207)Pb, 2.071 +/- 0.017 for (208)Pb/(206)Pb, 2.425 +/- 0.014 for (208)Pb/(207)Pb, 17.84 +/- 0.32 for (206)Pb/(204)Pb, 15.24 +/- 0.31 for (207)Pb/(204)Pb, and 37.31 +/- 0.52 for (208)Pb/(204)Pb. These ratios agree with those in the literature for several European regions. (206)Pb/(207)Pb distinguished the northwestern from the northeastern and southern Italian wines, and the southern samples were distinguishable only from the northwestern ones. (208)Pb/(206)Pb distinguished the northwestern from the southern Italian samples. Nevertheless, the lead IRs do not seem to be a very effective tool for the origin authentication of wines from different Italian regions. 相似文献
60.
An analytical method for the simultaneous determination of butachlor and benoxacor in wheat and soil
Butachlor is a chloroacetanilide herbicide successfully employed in weeding some important crops, and benoxacor is a safening compound able to induce the enzymatic mechanism of chloroacetanilide detoxification in plants. A practical method for a simultaneous detection of butachlor and benoxacor residues in wheat and in soil is described. The procedure can be performed by GC and HPLC. They were extracted with methanol and cleaned up by solid phase extraction (SPE). The analytes were satisfactorily separated via both GC and HPLC techniques, and no interferences were observed coming from plant or soil matrixes or reagents. The limit of quantitation was found to be 5.0 ng by GC and 20.0 ng by HPLC for butachlor and 2.5 ng by GC and 15.0 ng by HPLC for benoxacor. Butachlor recovery tests ranged from 85.4% to 91.7% in wheat shoots and 84.0% to 93.2% in soil; benoxacor recovery tests ranged from 86.5% to 90.8% in wheat shoots and 85.7% to 90.7% in soil. The reproducibility and the accuracy make this method a selective and sensitive tool for routine analyses. 相似文献