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排序方式: 共有1344条查询结果,搜索用时 15 毫秒
101.
102.
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
103.
Los Weinert P Pezza HR de Oliveira JE Pezza L 《Journal of agricultural and food chemistry》2004,52(26):7788-7792
A simple, rapid, and sensitive spectrophotometric method for routine analysis of saccharin in commercial noncaloric sweeteners is proposed. This method is based on the reaction of saccharin with tetrachloro-p-benzoquinone (p-chloranil) accelerated by hydrogen peroxide and conducted in an ethanol:acetone (4:1) medium, producing a violet-red compound (lambda(max) = 550 nm). Beer's law is obeyed in a concentration range of 2.05 x 10(-4) to 3.00 x 10(-3) M with an excellent correlation coefficient (r = 0.9998). The detection limit was 1.55 x 10(-5) M, and the effect of interferences on the spectrophotometric measurements was evaluated. The proposed procedure was applied successfully to the determination of saccharin in noncaloric sweeteners. Recoveries were within 99.2-104.3% with standard deviations ranging from to 0.5-1.6%. Results of the proposed method compare very favorably with those given by the high-performance liquid chromatography method recommended by the Food and Drug Administration. 相似文献
104.
Romero-Bastida CA Flores-Huicochea E Martin-Polo MO Velazquez G Torres JA 《Journal of agricultural and food chemistry》2004,52(8):2230-2235
The effect of moisture content and film composition on biodegradability is the focus of this study. Flexible films were first characterized for the effect on water sorption isotherms of relative humidity, temperature, zein content, and the addition of the plasticizers stearic acid, poly(ethylene glycol), or etoxylated ricine oil. Zein/ethylcellulose (EC) mixture films had a behavior between that for pure zein and EC films, which had the lowest water sorption. For films with plasticizer, the lowest water sorption at 25 degrees C was observed for those with stearic acid. Biodegradability of zein/EC films, evaluated using bacterial cultures selected for their zein proteolytic activity and isolated from a local solid waste landfill and a lagoon, showed no plasticizer effect even though its effect on moisture content was significant. Large differences were observed at different film zein concentration with the highest biodegradability for 100% zein. However, biodegradability did not mimic the water sorption behavior of zein/EC mixture films. 相似文献
105.
Vonderheide AP Wrobel K Kannamkumarath SS B'Hymer C Montes-Bayón M Ponce De León C Caruso JA 《Journal of agricultural and food chemistry》2002,50(20):5722-5728
Brazil nuts have been classified as the foodstuffs that contain the highest level of unadulterated selenium, an essential trace element that appears to prevent cancer. To date, characterization of the selenium species in brazil nuts has not yet been investigated. In this work, various sample preparation approaches, including microwave extractions and enzymatic treatments, are examined with the goal of species preservation and subsequent selenium speciation; of these approaches, an enzymatic treatment with Proteinase K proved most effective. High-performance liquid chromatography (HPLC) separation strategies and inductively coupled plasma mass spectrometry (ICP-MS) detection schemes will also be presented. Extracts are evaluated against available standards for the commercially obtainable seleno-amino acids, selenomethionine (SeMet), selenoethionine (SeEt), and selenocystine (SeCys); selenomethionine was demonstrated to be the most abundant of these seleno-amino acids. Further characterization of unidentified selenium-containing peaks is attempted by the employment of several procedures, including electrospray-mass spectrometry (ES-MS). A peptide structure was identified; however, this was considered a tentative proposal due to the large background produced by the extremely complicated brazil nut matrix. 相似文献
106.
Nitrogen Dynamics Under Excrement Patches in Pastures Soil mineral nitrogen contents in relation to time were measured under excrement patches on three pastures in Lower Saxony. The highest values were found under patches of urine on a pasture grazed by suckling cows. The herbage dry matter of that pasture showed a crude protein content of 19 %. The contents of mineral nitrogen under urine patches were less on a comparable pasture utilized by milking cows. The concentrations were still less on a cow grazed pasture, which remained unfertilized over a period of ten years. The content of NH4-N under urine affected areas increased distinctly in the whole soil profile, within one day of deposition. High NO3-N concentrations were found even in deeper soil layers after one week. The nitrogen concentrations under patches of urine approximated the values under not urine affected parts of the pasture within three months. The increments of mineral nitrogen under patches of faeces were insignificant. 相似文献
107.
Fernando Machado-Stredel Benedictus Freeman Daniel Jiménez-Garcia Marlon E.Cobos Claudia Nu?ez-Penichet Laura Jiménez Ed Komp Utku Perktas Ali Khalighifar Kate Ingenloff Walter Tapondjou Thilina de Silva Sumudu Fernando Luis Osorio-Olvera A.Townsend Peterson 《中国鸟类》2022,(1):1-10
Studies of biodiversity dynamics have been cast on either long(systematics)or short(ecology)time scales,leaving a gap in coverage for moderate time scales of de... 相似文献
108.
Plantlets were obtained from usually dormant axillary buds, excised from the crown of pineapple (Ananas comosus L. Merr.) and grown in culture. Multiple shoots arose from single buds grown on Murashige and Skoog medium supplemented with auxins and kinetin. Shaking culture-flasks during growth increased the number of multiple shoots formed, when compared with stationary liquid cultures. Leaf explants excised from in vitro plantlets developed into a callus capable of plantlet regeneration. Subjecting developing buds to surgical segmentation also resulted in multiple shoot formation. Such shoots, when excised and grown on Murashige and Skoog medium supplemented with auxins, developed roots and grew into complete plantlets capable of being grown in soil. 相似文献
109.
Niza-Ribeiro J Pereira A Souza J Madeira H Barbosa A Afonso C 《Preventive veterinary medicine》2005,72(1-2):81-5; discussion 215-9
A study to evaluate BVDV-prevalence, recent -contact and -vaccine use in dairy herds in the "Entre Douro e Minho" (EDM) region in North Portugal was carried out in 124 dairy herds in 2003. Herds were visited to ascertain BVDV-vaccine use and to collect a bulk tank milk (BTM) sample and serum from 1268 cattle to analyse BVDV-antibodies using an NS2-3 ELISA. Fifty-three percent of farmers used inactivated BVDV-vaccines whilst the remaining farmers were not presently using BVDV-vaccines. BMT-antibody results included 35% positives, 25% negative and 39% inconclusive, and were similar in vaccinated and non-vaccinated herds (p>0.05) and allowed estimating a 10% BVDV herd-prevalence from prior knowledge of the relationship between BMT-antibody results and probability of PI cattle in the herd. Overall individual seroprevalence was 27% and was 23% in non-vaccinated and 36% in vaccinated cattle (p<0.05). Contact of the herd with BVDV was assessed according to seroprevalence in young and adult cattle in the herd and it was estimated that 35% of herds were infected or had recent contact with BVDV, 40% were not infected and did not have recent contact with BVDV and the BVDV-infection and -contact status of remaining herds was undetermined. The results from this study indicate BVDV is endemic and BVDV-vaccines are widespread in the dairy-cattle population in EDM region in Portugal. 相似文献
110.
During pregnancy the developing embryo/foetus is completely dependent on the supply with nutrients and the removal of metabolic by-products through the maternal organism. Therefore, each lasting inadequate nutrient supply may have serious consequences for foetal development. As a kind of "nutritional programming" resulting adaptive changes may be maintained until or manifested at adult age. Intrauterine growth retardation (IUGR) may cause problems in animal health and result in poor animal performance. The relationships between prenatal development and the postnatal phenotypic appearance of muscle and fat are insufficiently investigated. The present paper provides selected aspects of the prenatal development of skeletal muscle (myogenesis) and adipose tissue (adipogenesis), refers to the importance of interactions between both tissues and is focussed on the influence of maternal nutrition on these processes. 相似文献