首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.

Purpose  

A review of the role of the carotenoids, lutein and zeaxanthin, and their function in altering the pathogenesis of age-related macular degeneration (AMD).  相似文献   

2.

Background

Soccer is a form of exercise that induces inflammatory response, as well as an increase in free radicals potentially leading to muscle injury. Balanced nutritional intake provides important antioxidant vitamins, including vitamins A, C and E, which may assist in preventing exercise-related muscle damage. The purpose of the present study was to determine the effect of macro/micronutrient intake on markers of oxidative stress, muscle damage, inflammatory and immune response in female soccer players.

Methods

Twenty-eight female players belonging to two soccer teams of the same professional soccer club participated in this study after being informed about the aims and procedures and after delivering written consent. Each team completed an 8-day dietary record and played one competition match the same week. Participants were divided into two groups: the REC group (who complied with recommended intakes) and the NO-REC group (who were not compliant). Laboratory blood tests were carried out to determine hematological, electrolytic and hormonal variables, as well as to monitor markers of cell damage and oxidative stress. Blood samples were obtained 24 h before, immediately after and 18 h after official soccer matches. Student t-test or Mann?CWhitney U-test was used to compare both groups throughout the match.

Results

At rest, we observed that the REC group had higher levels of total antioxidant status (TAS), glutathione peroxidase (GPx), and lower levels of creatine kinase (CK) and lactate dehydrogenase (LDH) in comparison to the NO-REC group. Immediately after the match, levels of TAS, GPx, superoxide dismutase (SOD), LDH and % lymphocytes were higher and the % of neutrophils were lower in the REC group compared to the NO-REC group. These differences were also maintained 18 h post-match, only for TAS and GPx.

Conclusions

Our data reveal an association between nutritional intake and muscle damage, oxidative stress, immunity and inflammation markers. The benefit of the intake of specific nutrients may contribute to preventing the undesirable physiological effects provoked by soccer matches.  相似文献   

3.
The aging of the population is giving rise to a large number of studies aimed at improving the quality of life, considering diet as a major contributing factor in this life stage. The objectives of the present study were to evaluate the nutritional status of a group of institutionalized elderly in Murcia, Spain, and to relate the diet to anthropometric and biochemical indices, paying special attention to total antioxidant status. The dietary evaluation showed excessive intakes of proteins and lipids, and deficiencies in those of carbohydrates, dietary fiber, zinc, iodine and vitamins A, E and D. The high proportion of overweight observed were not significantly correlated to the energy intakes. Although total plasma antioxidant status was low (0.62 mM eq Trolox and 0.98 mM eq Fe(II)) compared with reference values, estimated oxidative risk in this group of elderly was low according to plasma levels of vitamins C, A & E.  相似文献   

4.
A nutritional survey was conducted in an urban public maternity hospital, Hospital Gineco-Obstétrico Isidro Ayora (HGOIA), located in Quito, Ecuador. Seventy-four primiparas in the third trimester of pregnancy were recruited to assess the influence of sociedemographic factors on food patterns and nutrient intake, and the interrelationship between prenatal nutrient intake, maternal weight gain and pregnancy outcome. Results of the regression analysis indicated that maternal education was the factor most strongly associated with nutrient intake, followed by monthly per capita income. Maternal nutrient intake was next analyzed and compared with the WHO (1974, 1985) and NRC (1980) recommended daily allowances. Results also indicated the average daily intake of energy, protein, phosphorus, vitamins C and A, thiamine, riboflavin, and niacin met or exceeded the recommended daily allowances. Dietary calcium and iron intake, however, were below recommendations. Sodium and fat intake were both relatively high. Higher dietary fat intake was associated with increased birth weight, while lower protein intake was associated with increased risk of delivering a low-birth weight baby. Maternal weight gain during the third trimester predicted baby birth weight and height but not head circumference.  相似文献   

5.
Urban and peri-urban agriculture (UPA) has often been accused of being nutrient inefficient and producing negative externalities. To investigate these problems for the West African capital Niamey (Niger), nutrient inputs through fertilizer and manure to 10 vegetable gardens and 9 millet fields and nutrient offtakes through harvests were quantified during 24 months, and contamination of irrigation water and selected vegetables with faecal pathogens and heavy metals was determined. Annual partial horizontal balances for carbon (C), nitrogen (N), phosphorus (P) and potassium (K) amounted to 9,936 kg C ha−1, 1,133 kg N ha−1, 223 kg P ha−1 and 312 kg K ha−1 in high input vegetable gardens as opposed to 9,580 kg C ha−1, 290 kg N ha−1, 125 kg P ha−1 and 351 kg K ha−1 in low input gardens. In high input millet fields, annual surpluses of 259 kg C ha−1, 126 kg N ha−1, 20 kg P ha−1 and 0.4 kg K ha−1 were recorded, whereas surpluses of 12 kg C ha−1, 17 kg N ha−1, and deficits of −3 kg P ha−1 and −3 kg K ha−1 were determined for low input fields. Counts of Salmonella spp. and Escherichia coli yielded above threshold contamination levels of 7.2 × 104 CFU 25 g−1 and 3.9 × 104 CFU g−1 in lettuce irrigated with river water and fertilized with animal manure. Salmonella counts averaged 9.8 × 104 CFU 25 g−1 and E. coli 0.6 × 104 CFU g−1 for lettuce irrigated with wastewater, while these pathogens were not detected on vegetables irrigated with pond water. These results underline the need for urban gardeners to better adjust the nutrients applied to crop requirements which might also reduce nutrient accumulations in the soil and further in the edibles parts of the vegetables. Appropriate pre-treatment of irrigation water would help improve the quality of the latter and enhance the food safety of vegetables determined for the urban markets.  相似文献   

6.
Field experiments were conducted during 1984–1986 on an alluvial (Typic Ustochrept) soil (pH 8.0, organic carbon 0.46%) at IARI farm, New Delhi to study the changes in available soil nutrients (N, P, K, Mn, Fe, Zn and Cu) at different production levels. Fertilizer was applied to wheat followed by maize, based on the Targetted yield concept, and mustard was grown after the sequence to estimate the residual effect of nutrients. Nutrient applications for the largest yield targets (6 t ha–1 of wheat followed by 4 or 5 t ha–1 of maize) resulted in a comparatively greater buildup of soil nutrients (N, P and K), the greatest yield of a succeeding mustard crop, and a better soil nutrient status than that at the start of the experiment, even after the mustard. When both crops were fertilized for the largest target yield with straight fertilizers (Urea, SSP and KCl), the additions of N, P and K and of micronutrient cations (Mn, Fe, Zn and Cu) maintained a favorable balance for major and trace nutrients and provided a sound basis for profitable crop production.Part of the Ph.D. thesis of the senior author submitted to the Indian Agricultural Research Institute (IARI), New Delhi.  相似文献   

7.
ABSTRACT: BACKGROUND: In the 1970s, men in northern Sweden had among the highest prevalences of cardiovascular diseases (CVD) worldwide. An intervention program combining population- and individual-oriented activities was initiated in 1985. Concurrently, collection of information on medical risk factors, lifestyle and anthropometry started. Today, these data make up one of the largest databases in the world on diet intake in a population-based sample, both in terms of sample size and follow-up period. The study examines trends in food and nutrient intake, serum cholesterol and body mass index (BMI) from 1986 to 2010 in northern Sweden. METHODS: Cross-sectional information on self-reported food and nutrient intake and measured body weight, height, and serum cholesterol were compiled for over 140,000 observations. Trends and trend breaks over the 25-year period were evaluated for energy- providing nutrients, foods contributing to fat intake, serum cholesterol and BMI. RESULTS: Reported intake of fat exhibited two significant trend breaks in both sexes: a decrease between 1986 and 1992 and an increase from 2002 (women) or 2004 (men). A reverse trend was noted for carbohydrates, whereas protein intake remained unchanged during the 25-year period. Significant trend breaks in intake of foods contributing to total fat intake were seen. Reported intake of wine increased sharply for both sexes (more so for women) and export beer increased for men. BMI increased continuously for both sexes, whereas serum cholesterol levels decreased during 1986 - 2004, remained unchanged until 2007 and then began to rise. The increase in serum cholesterol coincided with the increase in fat intake, especially with intake of saturated fat and fats for spreading on bread and cooking. CONCLUSIONS: Men and women in northern Sweden decreased their reported fat intake in the first 7 years (1986-1992) of an intervention program. After 2004 fat intake increased sharply for both genders, which coincided with introduction of a positive media support for low carbohydrate-high-fat (LCHF) diet. The decrease and following increase in cholesterol levels occurred simultaneously with the time trends in food selection, whereas a constant increase in BMI remained unaltered. These changes in risk factors may have important effects on primary and secondary prevention of cardiovascular disease (CVD).  相似文献   

8.
9.
Low soil fertility and pest pressure are two causes of the decline in banana (Musa AAA) production in central Uganda. Foliar analysis by the Diagnosis and Recommendation Integrated System (DRIS) pinpoints K and Mg as the most limiting nutrients. This study tested the effects of K and Mg additions on plant performance and weevil damage for 2.75 yr, at Buligwe in central Uganda and Muyogo in southwest Uganda. All treatments received 25 kg P ha–1 and 100 kg N ha–1 annually, while K and Mg were applied (kg ha–1) at 0 K–0 Mg, 100 K–0 Mg, 100 K–25 Mg and 100 K–50 Mg. Fresh fruit yields (Mg ha–1 yr–1) ranged from 3.2 to 5.0 at Buligwe and 14.4 to 18.9 at Muyogo, with similar treatment trends at both sites. The 100 K–0 Mg treatment produced higher yields than no-K control (p = 0.022 for the combined dataset). Yields with K+Mg tended to be lower than with K only, though not significantly different. Foliar nutrient concentrations were little affected by treatments, but varied substantially among sample dates. With increasing cumulative rainfall between foliar samplings, foliar P declined (p = 0.077), K declined (ns), and Ca and Mg increased (p = 0.02 to 0.03). Weevil damage was higher at Buligwe, but was little affected by K and Mg treatments at either site.  相似文献   

10.
In southwest Niger, West Africa, fallows contribute little to crop land fertilityrestoration through crop and fallow cycles, because of their short duration andthe intensity of their use as a source for forage. However, they indirectlyplayan important role in crop land fertility, because they form the origin of alarge part of livestock-mediated nutrient transfers from rangelands to croplands, at least for households owning large herds. This study was carried outinthe village of Ticko, where forage resources originated from crop residues onfields during the dry season, and from plateau and fallow rangelands throughoutthe whole year. Fallow areas comprised 23% of the grazing resources. Theirforage production was relatively low: 1903 kg DMha–1 on average, during the period1996–2000, but they provided 38% of the palatable forage resources.Fieldsare manured every 5 years by night corralling of livestock on cropland. The average amounts of manure deposited on manured areas were 10.5tDM ha–1 yr–1. Despite a stocking rateof 24 Tropical Livestock Units (TLU) km–2 (250kg liveweight), equal to the carrying capacity, manured areascomprised only 9% of all crop lands. In total 394 t DM of manurewas transferred from natural grazing areas and non-manured crop lands tomanured fields, 62.5% originating from fallow areas and 31.5% from non-manuredcrop lands. This leads in the medium term to a decrease in fertility of a largepart of the fields owned by farmers and smallholder agro-pastoralists.Consequently, if this trend continues the system is not sustainable in the longterm.  相似文献   

11.
12.
Grazed pastures emit ammonia (NH3) into the atmosphere; the size of the NH3 loss appears to be related to nitrogen (N) application rate.The micrometeorological mass balance method was used to measure NH3 volatilization from rotationally grazed swards on three plots in the autumn of 1989 and throughout the 1990 growing season. The aim of the research was to derive a mathematical relationship between NH3 volatilization and N application rate, which would vary between soil type and weather conditions. In both years the plots received a total of 250, 400 or 550 kg N ha–1 as calcium ammonium nitrate (CAN) split over 6 to 8 dressings. The number of grazing cycles ranged from 7 to 9 for the three N plots.In the last two grazing cycles of 1989, NH3 losses were 3.8, 12.0 and 14.7 kg N ha–1 for the 250N, 400N and 550N plots, which was equivalent to 5.3%, 13.9% and 14.4% of the amount of N excreted on the sward, respectively. In 1990, NH3 losses were 9.1, 27.0 and 32.8 kg N ha–1 for the 250N, 400N and 550N plots, which was equivalent to 3.3%, 6.9% and 6.9% of the N excreted, respectively. Differences in urine composition between the plots were relatively small. Rainfall and sward management affected the size of the NH3 volatilization rate. Volatilization of NH3 was related to N excretion and N application rate.A calculation procedure is given to enable the estimation of NH3 volatilization from N application rate. Adjustments can be made for grazing efficiency, grazing selectivity, N retention in milk and liveweight gain, concentrate N intake and milking duration. Losses of NH3 increase progressively with an increase in N application rate until herbage yield reaches a maximum at an application rate of about 500 kg N ha–1 yr–1.  相似文献   

13.

Background  

Compared with other common plant foods, walnuts (Juglans regia) are consistently ranked among the highest in antioxidant capacity. In vitro, walnut polyphenols inhibit plasma and LDL oxidation, while in animal models they lower biomarkers of oxidative stress and raise antioxidant capacity. A limited number of human feeding trials indicate that walnuts improve some measures of antioxidant status, but not others.  相似文献   

14.

Background

Age-related macular disease is the leading cause of blind registration in the developed world. One aetiological hypothesis involves oxidation, and the intrinsic vulnerability of the retina to damage via this process. This has prompted interest in the role of antioxidants, particularly the carotenoids lutein and zeaxanthin, in the prevention and treatment of this eye disease.

Methods

The aim of this randomised controlled trial is to determine the effect of a nutritional supplement containing lutein, vitamins A, C and E, zinc, and copper on measures of visual function in people with and without age-related macular disease. Outcome measures are distance and near visual acuity, contrast sensitivity, colour vision, macular visual field, glare recovery, and fundus photography. Randomisation is achieved via a random number generator, and masking achieved by third party coding of the active and placebo containers. Data collection will take place at nine and 18 months, and statistical analysis will employ Student's t test.

Discussion

A paucity of treatment modalities for age-related macular disease has prompted research into the development of prevention strategies. A positive effect on normals may be indicative of a role of nutritional supplementation in preventing or delaying onset of the condition. An observed benefit in the age-related macular disease group may indicate a potential role of supplementation in prevention of progression, or even a degree reversal of the visual effects caused by this condition.
  相似文献   

15.
To provide data on the diagnosis and correction of deficiencies of K, Mg and high Mn experienced in the banana plantations of New South Wales, a sand culture experiment, in 1 m3 containers, was conducted using ‘Williams’ banana. Here we report the effects of K, Mg and Mn treatments on plant and root uptake rates of N, P, K, Ca, Mg, Na, Mn, Cu and Zn and the interaction beween K, Mg and Mn. Increased K supply increased the plant uptake rate of K and P whereas N, Ca, Mg and Cu were decreased. There was no large overall effect of Mg supply on the uptake of elements other than Cu. Within the K series the proportion of roots decreased as K supply increased and the root uptake rate of K, Mg, Mn and Cu was proportional to the concentration in the external medium. For other elements uptake was influenced more by demand within the plant. High Mn supply reduced the uptake of Ca, Mg and Zn but had little effect on the other elements. Values of root uptake rate were only 10% of those reported on other crops, but our data apply to a long time period (~ 1300 days). K and Mn non-competitively inhibited Mg uptake. The K/(Ca + Mg) ratio of the lamina was unable to distinguish between K and Mg deficiency as it did not show an optimum relationship with yield.  相似文献   

16.

Background

Hormones, which influence satiety and hunger, play a significant role in body energy balance regulation. Ghrelin is a peptide that plays an important role in short-term appetite regulation, whereas leptin is a factor that controls long-term energy balance and is considered as a satiety hormone. The aim of this study was to evaluate the leptin/ghrelin ratio in a fasting state and after the intake of meals with varying macronutrient contents and to assess the possible differences between normal body weight and overweight/obese men.

Methods

We examined 46 healthy adult men (23 with normal body weight and 23 overweight/obese) aged 21–58, who were divided into two groups. In the crossover study, participants received isocaloric (450?kcal) meals with different macronutrient contents: men from the first group received high-carbohydrate (HC) and normo-carbohydrate (NC) meals, and in the second group, participants received high-carbohydrate and high-fat (HF) meals. The ratio of leptin/ghrelin levels was calculated from leptin and total ghrelin serum concentrations in a fasting state and 30, 60, 120, 180 and 240?min after meal intake. One-way ANOVA and Wilcoxon signed-rank tests were carried out. The normality of the variable distribution was checked with the Shapiro–Wilk test, the homogeneity of variances was verified with the Levene test, and the false discovery rate p-value adjustment method was used.

Results

The leptin/ghrelin ratio was significantly higher in overweight/obese men than individuals with normal body weight in a fasting state, as well as postprandially. We observed trends towards a higher leptin/ghrelin ratio values from the 60?min after HC-meal intake compared to the NC- and HF-meals in normal body weight participants, while in overweight/obese men, we did not note any significant differences dependent on the meal type.

Conclusions

We have observed a significantly different postprandial leptin/ghrelin ratio in normal body weight and overweight/obese men, and our results suggest that in men with normal body weight, a greater feeling of satiety may occur after high-carbohydrate meal intake, which was not noted in the overweight/obese individuals.
  相似文献   

17.
成琳  粟晶 《应用化工》2007,36(12):1247-1248,1254
研究了抗氧剂264的烷基化产物的气相色谱分析,对不同类型的色谱柱进行了筛选,全面考察色谱分析的各种条件及影响因素,建立了OV-1毛细管柱分离,以内标法定量的分析法,结果准确,对甲酚回收率为99.1%~103%,2,4酚回收率为98.5%~100%,264回收率为97.2%~99.5%。  相似文献   

18.
A 19-year field experiment on a Mollisol agroecosystem was carried out to study the productivity of a wheat-maize-soybean rotation and the changes in soil carbon and nutrient status in response to different fertiliser applications in Northeast China. The experiment consisted of seven fertiliser treatments: (1) unfertilised control, (2) annual application of P and K fertilisers, (3) N and K fertilisers, (4) N and P fertilisers, (5) N, P and K fertilisers, (6) N, K and second level P fertilisers, and (7) N, P and second level K fertilisers. Without fertiliser, the Mollisols could support an average yield of 1.88 t ha−1 for wheat, 3.89 t ha−1 for maize and 2.12 t ha−1 for soybean, compared to yields of 3.20, 9.30 and 2.45 t ha−1 respectively for wheat, maize and soybean if the crop nutrient demands were met. At the potential yield level, the N, P and K removal by wheat are 79 kg N ha−1, 15 kg P ha−1, and 53 kg K ha−1, by maize are 207 kg N ha−1, 47 kg P ha−1, and 180 kg K ha−1, by soybean are 174 kg N ha−1, 18 kg P ha−1, and 55 kg K ha−1. Crop yield, change in soil organic carbon (SOC), and the total and available nutrient status were used to evaluate the fertility of this soil over different time periods. This study showed that a fertiliser strategy that was able to maintain yields in the short term (19 years) would not maintain the long term fertility of these soils. Although organic carbon levels did not rise to the level of virgin soil in any treatment, a combination of N, P and K fertiliser that approximated crop export was required to stabilise SOC and prevent a decline in the total store of soil nutrients.  相似文献   

19.
Tocopherols, phytosterols, carotenoids, and squalene are present in mature seeds of Japanese quince. Yet, little is known about the relationship between these compounds and oil yield during fruit and seed development. The profile change of lipophilic compounds during fruit and seed development in Japanese quince cultivars “Darius,” “Rondo,” and “Rasa” is investigated. It is shown here that during fruit and seed development, there is a significant reduction, three‐ to over tenfold, in the concentration of minor bioactive compounds in seed oil. It is recorded that delay between synthesis of tocopherols and oil in Japanese quince seeds during the fruit development results in a logarithmic relationship between the oil content and tocopherols concentration in the seed oil (R2 = 0.980). Similar trends are observed between oil yield and phytosterols, and carotenoids (R2 = 0.927 and R2 = 0.959, respectively). The profile of fatty acids during the development of the seeds significantly is changed. The reduction of linoleic, palmitic, and gondoic acids levels and increment of oleic acid is noted. The oil content, profile of fatty acids, and concentration of bioactive compounds in all three genotypes of Japanese quince do not change significantly statistically during the last month of fruit development. Practical Applications: Some fruits are harvested at different degrees of maturity mainly due to a logistic issue and uneven ripening of fruits, which affects the chemical composition of whole fruit including seeds. Therefore, it would be good to know how the chemical composition is changing in plant material during development especially in the last month before harvest. Production of Japanese quince continues to rise year to year and with it the volume of generated by‐products such as seeds. This study demonstrates how it changes the oil content, profile of fatty acid, and concentration of tocopherols, squalene, phytosterols, and carotenoids in the seeds and seed oil of three Japanese quince cultivars “Rondo,” “Darius,” and “Rasa” during plant development. The provided information can be very useful for the manufactories oriented on the processing of by‐products, mainly seeds, generated by other branches of industry, for instance, fruit‐processing.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号