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1.
Vitamin A deficiency produces anemia and altered iron status. In this study with rats we tested two hypotheses regarding vitamin A deficiency: (1) that it impairs erythropoiesis, leading to an increased red cell turnover, and (2) that it inhibits the glycosylation of transferrin. Erythropoietic activity was assessed indirectly by determining the myeloid:erythroid ratio in bone marrow smears, the number of erythroid colonies in the red pulp of spleen, the blood reticulocyte index, and zinc protoporphyrin and plasma transferrin receptor concentrations. Transferrin glycosylation was assessed by measuring the sialic acid content of transferrin. The effects of vitamin A deficiency were compared with those of iron deficiency. Iron deficiency produced anemia and low iron levels in organs. Vitamin A deficiency produced low levels of plasma and hepatic retinol, and it induced decreased plasma total iron-binding capacity and raised iron levels in tibia and spleen. Short- but not long-term iron deficiency reduced the number of erythroid colonies in spleen; vitamin A deficiency had no influence. Neither iron nor vitamin A deficiency influenced the myeloid:erythroid ratio in bone marrow smears and the blood reticulocyte production. Plasma transferrin receptor and erythrocyte zinc protoporphyrin concentrations were not affected by vitamin A deficiency but increased with iron deficiency. Vitamin A deficiency did not stimulate erythrocyte breakdown, as indicated by unaltered plasma lactate dehydrogenase activity and reduced plasma total bilirubin levels. Both vitamin A and iron deficiencies raised the proportion of multiple sialylated transferrins in plasma. Thus, we have not found evidence that vitamin A deficiency affects erythropoiesis and erythrocyte turnover. The iron accumulation in spleen and bone marrow may be related to reduced iron transport due to inhibition of transferrin synthesis rather than inhibition of transferrin sialylation.  相似文献   
2.
A high intake of olive oil has been proposed as an explanation for the low incidence of coronary heart disease in Mediterranean countries, but it is unclear whether olive oil offers specific benefits beyond a low content of saturated fat. Some types of extra virgin olive oil are rich in non-polar phenols, which might be taken up by plasma LDL particles and protect these from becoming atherogenic by oxidative modification. In a pilot study we found that consumption of 47 g fortified olive oil containing 31 mg phenols significantly increased the lag time of LDL oxidation from 112 ± 5 min before to 130 ± 7 min 2h after the meal. However, this study was not controlled, and in the current study we therefore investigated whether olive oil phenols increase the lag time of LDL oxidation in postprandial samples when compared with a control group.

Twelve healthy men and women consumed four different olive oil supplements with a meal on four separate occasions: one similar to the supplement in the pilot study (positive control); one containing mainly non-polar olive oil phenols; one containing mainly polar olive oil phenols; and one without phenols (placebo). Lag time significantly increased 2 h after the meals with the positive control (8 ± 2 min), the polar phenols (8 ± 2 min), and the placebo (8 ± 2 min), but not after the non-polar phenols (-0.4 ± 3 min). Increases were not statistically different between supplements.

These results indicate that the lag time of LDL-oxidation is increased after consumption of a meal. This increase is probably due to non-specific meal or time effects and not to phenols from olives or olive oil. Furthermore, these findings stress the need for adequate controlled studies to avoid misinterpretations of the data.  相似文献   
3.

Introduction

Nutrient profiling is defined as the science of categorising foods based on their nutrient composition. The Choices Programme is a nutrient profile system with criteria that determine whether foods are eligible to carry a “healthier option” stamp. The Daily Menu Method which has been developed to evaluate these criteria is described here. This method simulates the change in calculated nutrient intakes which would be the result of consumers changing their diets in favour of food products that comply with the criteria.

Methods

Average intakes of energy, trans fatty acids (TFA), saturated fatty acids (SAFA), sodium, added sugar and fibre were derived from dietary intake studies and food consumption surveys of 7 countries: The Netherlands, Greece, Spain, the USA, Israel, China and South Africa. For each of the key nutrients, these average intakes were translated into three Typical Daily Menus per country. Average intakes based on these three menus were compared with average intakes from three Choices Daily Menus. To compose the Choices Menus, foods from the Typical Menus that did not comply with the Choices criteria were replaced with foods that did comply and are available on the market.

Results

Comparison of intakes from the Choices Menus with the survey data showed that calculated intakes of energy, SAFA, TFA, sodium and added sugar were reduced. Fibre intakes were increased. The size of the effect differed per country.

Conclusion

The Daily Menu Method is a useful means to predict the potential effects of nutrient profiles such as the Choices criteria, on daily nutrient intakes. The method can be applied internationally and confirms that the criteria of the Choices Programme are in line with the aim of the programme: to improve nutrient intakes in the direction of the recommendations.  相似文献   
4.

Background

Curative radiotherapy or chemoradiation for head and neck cancer (HNC) may result in severe acute and late side effects, including tube feeding dependence.The purpose of this prospective cohort study was to develop a prediction model for tube feeding dependence 6 months (TUBEM6) after curative (chemo-) radiotherapy in HNC patients.

Patients and Methods

Tube feeding dependence was scored prospectively. To develop the multivariable model, a group LASSO analysis was carried out, with TUBEM6 as the primary endpoint (n = 427). The model was then validated in a test cohort (n = 183). The training cohort was divided into three groups based on the risk of TUBEM6 to test whether the model could be extrapolated to later time points (12, 18 and 24 months).

Results

Most important predictors for TUBEM6 were weight loss prior to treatment, advanced T-stage, positive N-stage, bilateral neck irradiation, accelerated radiotherapy and chemoradiation. Model performance was good, with an Area under the Curve of 0.86 in the training cohort and 0.82 in the test cohort. The TUBEM6-based risk groups were significantly associated with tube feeding dependence at later time points (p<0.001).

Conclusion

We established an externally validated predictive model for tube feeding dependence after curative radiotherapy or chemoradiation, which can be used to predict TUBEM6.  相似文献   
5.

Introduction

The Choices Programme is an internationally applicable nutrient profiling system with nutrition criteria for trans fatty acids (TFA), saturated fatty acids, sodium, added sugar and for some product groups energy and fibre. These criteria determine whether foods are eligible to carry a “healthier option” stamp. In this paper a nutrient intake modelling method is described to evaluate these nutritional criteria by investigating the potential effect on nutrient intakes.

Methods

Data were combined from the 2003 Dutch food consumption survey in young adults (aged 19–30) and the Dutch food composition table into the Monte Carlo Risk Assessment model. Three scenarios were calculated: the “actual intakes” (scenario 1) were compared to scenario 2, where all foods that did not comply were replaced by similar foods that did comply with the Choices criteria. Scenario 3 was the same as scenario 2 adjusted for the difference in energy density between the original and replacement food. Additional scenarios were calculated where snacks were not or partially replaced and stratified analyses for gender, age, Body Mass Index (BMI) and education.

Results

Calculated intake distributions showed that median energy intake was reduced by 16% by replacing normally consumed foods with Choices compliant foods. Intakes of nutrients with a maximal intake limit were also reduced (ranging from −23% for sodium and −62% for TFA). Effects on intakes of beneficial nutrients varied from an unintentional reduction in fat soluble vitamin intakes (−15 to −28%) to an increase of 28% for fibre and 17% calcium. Stratified analyses in this homogeneous study population showed only small differences across gender, age, BMI and education.

Conclusions

This intake modelling method showed that with consumption of Choices compliant foods, nutrient intakes shift towards population intake goals for the nutrients for which nutrition criteria were defined, while effects on beneficial nutrients were diverse.  相似文献   
6.
Hypermethylation is an important mechanism for the dynamic regulation of gene expression, necessary for metastasizing tumour cells. Our aim is to identify methylation tumour markers that have a predictive value for the presence of regional lymph node metastases in patients with oral and oropharyngeal squamous cell carcinoma (OOSCC). Significantly differentially expressed genes were retrieved from four reported microarray expression profiles comparing pN0 and pN+ head-neck tumours, and one expression array identifying functionally hypermethylated genes. Additional metastasis-associated genes were included from the literature. Thus genes were selected that influence the development of nodal metastases and might be regulated by methylation. Methylation-specific PCR (MSP) primers were designed and tested on 8 head-neck squamous cell carcinoma cell lines and technically validated on 10 formalin-fixed paraffin-embedded (FFPE) OOSCC cases. Predictive value was assessed in a clinical series of 70 FFPE OOSCC with pathologically determined nodal status. Five out of 28 methylation markers (OCLN, CDKN2A, MGMT, MLH1 and DAPK1) were frequently differentially methylated in OOSCC. Of these, MGMT methylation was associated with pN0 status (P = 0.02) and with lower immunoexpression (P = 0.02). DAPK1 methylation was associated with pN+ status (P = 0.008) but did not associate with protein expression. In conclusion, out of 28 candidate genes, two (7%) showed a predictive value for the pN status. Both genes, DAPK1 and MGMT, have predictive value for nodal metastasis in a clinical group of OOSCC. Therefore DNA methylation markers are capable of contributing to diagnosis and treatment selection in OOSCC. To efficiently identify additional new methylation markers, genome-wide methods are needed.  相似文献   
7.
A high intake of olive oil has been proposed as an explanation for the low incidence of coronary heart disease in Mediterranean countries, but it is unclear whether olive oil offers specific benefits beyond a low content of saturated fat. Some types of extra virgin olive oil are rich in non-polar phenols, which might be taken up by plasma LDL particles and protect these from becoming atherogenic by oxidative modification. In a pilot study we found that consumption of 47 g fortified olive oil containing 31 mg phenols significantly increased the lag time of LDL oxidation from 112 ± 5 min before to 130 ± 7 min 2h after the meal. However, this study was not controlled, and in the current study we therefore investigated whether olive oil phenols increase the lag time of LDL oxidation in postprandial samples when compared with a control group.

Twelve healthy men and women consumed four different olive oil supplements with a meal on four separate occasions: one similar to the supplement in the pilot study (positive control); one containing mainly non-polar olive oil phenols; one containing mainly polar olive oil phenols; and one without phenols (placebo). Lag time significantly increased 2 h after the meals with the positive control (8 ± 2 min), the polar phenols (8 ± 2 min), and the placebo (8 ± 2 min), but not after the non-polar phenols (-0.4 ± 3 min). Increases were not statistically different between supplements.

These results indicate that the lag time of LDL-oxidation is increased after consumption of a meal. This increase is probably due to non-specific meal or time effects and not to phenols from olives or olive oil. Furthermore, these findings stress the need for adequate controlled studies to avoid misinterpretations of the data.  相似文献   
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