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排序方式: 共有481条查询结果,搜索用时 31 毫秒
1.
This study reports the development of a voltammetric method applied for Se determination in Phaeophyceae (A. utricularis, C. jacquinotii, A. mirabilis, D. anceps, H. grandifolius) and Rhodophyceae (G. confluens, C. racovitzae, I. cordata) macroalgae from the Antarctic. Evaluation of the instrumental parameters showed the square wave cathodic stripping voltammetry provided greater sensitivity (deposition potential, -0.4 V; deposition time, 420 s; amplitude, 0.08 V; frequency, 60 Hz) than influence of differential pulse cathodic stripping voltammetry. The matrix effect and the influence of Cu concentration on the determinations were also assessed. After microwave-assisted digestion of the samples, the quantification limit was from 5.21 × 10−3 (G.confluens) to 9.85 × 10−3 mg kg-1 (I. cordata). The quantification of Se was carried out over the concentration range from 0.23 (C. jacquinotii) to 1.22 mg kg-1 (A. mirabilis). The method accuracy was by analysing the reference material of peach leaves (SRM 1547).  相似文献   
2.

Background

The Dietary Guidelines for Americans (DGA) provide a framework for food and nutrition programming in the United States as well as the foundation for individualized dietary guidance. Public utilization of the DGA, specifically the MyPyramid or MyPlate tool, is not well studied.

Objective

The objective of this study was to evaluate the relationship between public knowledge of the 2010 DGA assessed by use of the MyPyramid or MyPlate dietary plan and various markers of diet intake (including dietary energy density and Food Patterns Equivalents Database component scores) in US adults.

Design

The National Health and Nutrition Examination Survey (NHANES) is a large, cross-sectional survey conducted continuously to monitor the health and nutritional status of US residents. The sampling design of NHANES allows for collection of a nationally representative sample.

Participants/setting

Data from a nationally representative sample of 3,194 adults>18 years with 1 complete day of dietary recall data during the 2011-2014 NHANES were used for this study. During NHANES, participants were asked about knowledge and use of the MyPyramid or MyPlate plan.

Main outcome measures

Mean daily dietary intake was compared between MyPyramid or MyPlate users and nonusers.

Statistical analyses performed

Multivariable regression models were then used to evaluate the relationship between use of MyPlate or MyPyramid and various food pattern components consumed daily. Models were adjusted for age, sex, race or ethnicity, education, household size, family income (using NHANES-provided poverty-to-income ratio), smoking status, beverage energy density, and physical activity.

Results

Subjects who reported using the MyPyramid or MyPlate plan had better diets than subjects who had not tried the MyPyramid or MyPlate plan. Users of MyPyramid or MyPlate had significantly lower dietary energy density (1.8 vs 1.9 kcal/g, P=0.0003) and significantly fewer servings of refined grains (5.9 vs 6.5 oz equivalents, P=0.0007) but more servings of whole grains (1.1 vs 0.8 oz equivalents, P=0.007), more dark green and leafy vegetables (P=0.006), and lower intake of added sugars (18 vs 21 tsp, P=0.0005) and solid fats (34 vs 39 g, P<0.0001) after adjusting for age, sex, race or ethnicity, education, household size, family income (using NHANES-provided poverty-to-income ratio), smoking status, beverage energy density, and physical activity.

Conclusion

In this nationally representative sample, reported use of MyPyramid or MyPlate was associated with more healthful dietary intakes. Future intervention studies are needed to explore facilitators and barriers for using MyPlate as well as the impact of MyPlate use on dietary intake behaviors.  相似文献   
3.
The intracellular development and differentiation of the Plasmodium parasite in the host liver is a prerequisite for the actual onset of malaria disease pathology. Since liver-stage infection is clinically silent and can be completely eliminated by sterilizing immune responses, it is a promising target for urgently needed innovative antimalarial drugs and/or vaccines. Discovered more than 65 years ago, these stages remain poorly understood regarding their molecular repertoire and interaction with their host cells in comparison to the pathogenic erythrocytic stages. The differentiating and replicative intrahepatic parasite resides in a membranous compartment called the parasitophorous vacuole, separating it from the host-cell cytoplasm. Here we outline seminal work that contributed to our present understanding of the fundamental dynamic cellular processes of the intrahepatic malarial parasite with both specific host-cell factors and compartments.  相似文献   
4.

Objectives

Nutrient intakes of children were surveyed at the time when a nation-wide shift took place in the Republic of Korea from agriculture-based to industrialized society. Taking advantage of the survey locations (see below), possible delay in nutritional improvement in rural areas (as compared with that in an urban area) was also examined.

Methods

In total, 108 4- to 6-year-old children (boys and girls in combination) in 4 kindergartens (KGs; 1 in Seoul and 3 in Jeju Island) participated in the survey in 2003–2004. 24-h food duplicate samples were prepared by the mother of each child. Food items in each duplicate sample were separated and coded with reference to the Dietary Reference Intake for Koreans (the 2005 version). Nutrient intake of the day was estimated from the code and weight followed by summation for daily intake.

Results

The children in the KG in Seoul studied were younger, and therefore were smaller in body size than those in other KGs. Thus, it was considered necessary to evaluate nutrient intake not only on a daily basis, but after adjustment for body weight. The AM daily intake of energy (protein in parenthesis) for the 108 children was 1479 kcal (55 g)/day or 69.8 kcal (2.6 g)/kg body weight/day. Evaluation by individual nutrient suggested that the intake was sufficient for almost all nutrients except for sodium and potassium. Sodium and potassium intake (2285 and 1840 mg/day, respectively) was in excess and insufficient, respectively, with potential risk of inducing hypertension later in life.

Conclusions

Inter-KG difference was not remarkable and therefore urban–rural difference was not apparent. Nutrient intakes as a whole appeared to be sufficient urban and rural areas. Nevertheless, excess Na intake coupled with insufficient K intake was a common problem.  相似文献   
5.
目的:分析我院住院患者中营养液医嘱不合理用药处方,提高在营养液使用中的合理用药水平。方法对我院静配中心2014年1-12月住院长期医嘱中的营养液医嘱不合理用药部分进行分类,总结与分析。结果2014年1-12月份共配置营养液医嘱1618袋,出现营养液不合理处方67张。其中第1季度28张,占41.79%;第2季度14张,占20.90%,第3季度11张,占16.42%,第4季度14张,占20.90%。主要涉及的内容有:配伍禁忌、用药剂量过大,或不符合浓度要求、药物间相互作用等。结论通过静配中心药师对医嘱的审核和干预,能有效地降低和避免不合理用药的产生,促进临床安全、合理的用药。  相似文献   
6.
Cauliflower (Brassica oleraceae L. var. Botrytis) is a good source of bioactive compounds, such as glucosinolates, phenolic compounds and vitamins. In this study, the effects of some processes (i.e. boiling, steaming) on the sinigrin bioaccessibility as a major glucosinolate found in cruciferous vegetables after in vitro digestion, also in vitro antimutagenic activities, total phenols and total antioxidant capacities of cauliflower were determined. The sinigrin content was reduced by approximately 9.6% and 29.1% in steamed and boiled cauliflower (p > 0.05), respectively. After in vitro simulated digestion, sinigrin content was decreased by 26.4% in raw samples, increased by 29.5% and 114.7% in steamed and boiled samples, respectively. In all samples, mutagenic effect to Salmonella typhimurium TA 100 was not seen. When samples were steamed, phenol content was increased by 14.83%. After boiling total phenol content of cauliflower was decreased by 1.8%. Total antioxidant capacities (TAC) measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3 ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods were increased by 47% and 39%, respectively (p < 0.05) in steamed samples and decreased by 8% and 7% with boiling, respectively (p > 0.05). TAC in raw sample of cauliflower, which was investigated in phosphomolybdenum assays, was determined as 18.7 mg ascorbic acid equivalents (AAE)/100 g. In all cases, the highest antioxidant activity was determined in the steamed samples, while the lowest antioxidant activity was in boiled samples.  相似文献   
7.
Culinary herbs and spices contain a variety of bioactive compounds including phylloquinone, the most common dietary form of vitamin K. In this study, we analyzed the phylloquinone content of a large number of commonly available culinary herbs, spices, and seasonings. Samples of fresh herbs (n = 19), dried herbs (n = 28), spices and seeds (n = 26), seasoning blends (n = 9), and other flavor enhancers (n = 11) were purchased in Montreal (Quebec, Canada) and Washington (DC, USA). All samples were analyzed in quadruplicate using standardized HPLC procedures. Most fresh herbs contained between 450 and 1200 μg of phylloquinone/100 g. Dried herbs were even richer with some (cilantro, marjoram, parsley) showing concentrations of ≈3000 μg/100 g. Phylloquinone content of spices and seeds was relatively low (5–250 μg/100 g), while being highly variable among seasoning blends (2.3–1878 μg/100 g). According to our results, portions of only 3 g of herbs can increase daily intakes of phylloquinone by up to 100 μg, contributing significantly to the daily vitamin K intake. Herbs can thus be important food sources of phylloquinone and should be accounted for when assessing vitamin K intakes in research or in patients treated with vitamin K antagonists. Future research should focus on the bioavailability of phylloquinone in these products.  相似文献   
8.
There is increasing interest by consumers, researchers, and regulators into the roles that certain bioactive compounds, derived from plants and other natural sources, can play in health maintenance and promotion, and even prolonging a productive quality of life. Research has rapidly emerged suggesting that a wide range of compounds and mixtures in and from plants (such as fruits and vegetables, tea and cocoa) and animals (such as fish and probiotics) may exert substantial health benefits. There is interest in exploring the possibility of establishing recommended intakes or dietary guidance for certain bioactive substances to help educate consumers. A key aspect of establishing dietary guidance is the assessment of safety/toxicity of these substances. Toxicologists need to be involved in both the development of the safety framework and in the evaluation of the science to establish maximum intake/upper limits.  相似文献   
9.
In this study, we explored the capacity of different tomato rootstocks to improve the nutritional value of tomatoes grown in a greenhouse during the winter–spring period under low temperature and light conditions. The results showed that relative to nongrafted plants, some grafted rootstocks either did not affect or had detrimental effects on the nutritional parameters measured. In addition, the amount of serotonin was significantly lower in tomatoes from all grafted rootstocks than in tomatoes from the nongrafted plants. Nevertheless, relative to the nongrafted plants, some grafted treatments increased total macroelements (by 1.16 times), total microelements (by 1.43 times), protein content (by 17%), free total and essential amino acids (by respectively 23% and 19%), total phenolic compounds (by 11%), vitamin C (by 13.8%), lycopene (by 48%), and also total hydrocinnamic acids (by 67%) and flavonoids (by 279%). As the grafted treatments did not increase the tomato yield, we hypothesize that these compounds accumulated in the tomatoes due to the lack of increased biomass, which prevented a dilution effect on the compounds of interest in the fruits.  相似文献   
10.
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