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1.
Objective: This study investigated the association between fruit and vegetable intake and stomach cancer, with considering the impacts of Helicobacter pylori (H. pylori) infection and tobacco smoking. Methods: A case-control study featuring 80 male incident stomach-cancer cases and 126 male controls was conducted in a general hospital in Viet Nam. A semi-quantitative food frequency and demographic lifestyle questionnaire were used; and venous blood samples were collected to determine H. pylori status by IgG ELISA. The respective associations between fruit and vegetable intake and stomach cancer were examined using unconditional logistic regression analysis with adjustments for possible cofactors. Results: Fruit intake and stomach cancer showed a weak inverse association when this became non-significant after adjusting for H. pylori infection (OR = 0.50, 95%CI: 0.22–1.12, p trend = 0.094). Stratifying by H. pylori status returned a negative trend for fruit intake and stomach cancer among H. pylori-negative participants (OR = 0.21, 95%CI: 0.06–0.69, p trend = 0.010), but no significant interaction for H. pylori-positive participants (OR = 0.76, 95%CI: 0.21–2.68, p trend = 0.670). Vegetable intake and stomach cancer showed no association, regardless of H. pylori status. Compared to ever-smokers with low intake, never-smokers with high vegetable (OR = 0.25, 95% CI: 0.06–0.95) and fruit intake (OR = 0.20, 95%CI: 0.06–0.65) showed the lowest odds of stomach cancer. Conclusions: Fruit, but not vegetable, intake showed a weak inverse association with stomach cancer. H. pylori infection and tobacco-smoking status may influence the protective effects of fruit and vegetable intake on stomach cancer.  相似文献   
2.
Screening of the antiradical action of vegetable oils   总被引:2,自引:0,他引:2  
Information on radical scavenging activity (RSA) and antioxidant potential of vegetable oils are not reported, or reporting has been rather limited. Such data is of importance for the evaluation of nutritional and health impact of these oils. The main objective of this short study was to compare the antiradical performance of some common and unusual vegetable oils. The described arrangement for our simple experiment uses the addition of stable radicals 1,1-diphenyl-2-picrylhydrazyl (DPPH) to vegetable oils, which are decomposed by components having antioxidant properties. The order of effectiveness of oils in inhibiting free radicals was as follows: coriander>blackcumin>cottonseed>peanut>sunflower>walnut>hemp seed>linseed>olive>niger seed. This initial survey might serve as a springboard for future research into this area.  相似文献   
3.
两种维生素C测定方法的比较   总被引:5,自引:0,他引:5  
目的 :研究 2 ,6 -二氯酚靛酚法与 2 ,4 -二硝基苯肼法测定蔬菜和水果及尿液中抗坏血酸含量之间的关系。方法 :对蔬菜和水果样品 ,及扬州医学院大学生和市某幼儿园儿童 3h尿总量 ,收集前受试者排空小便后 ,口服 5 0 0 m g维生素C片剂 ,饮水 4 0 0 ml。分别用上述两种方法进行测定样品中维生素 C。结果 :在冬瓜和黄瓜中 ,两种方法所测维生素 C结果差异无统计学意义 ,而在黄豆芽和绿豆芽中 ,两种方法测定结果差异有统计学意义。对于尿样中的维生素 C,2 ,6 -二氯酚靛酚法所测定结果明显高于 2 ,4 -二硝基苯肼法 ,两者有明显的相关关系 ,其回归方程为 Y=- 14 .5 7 0 .5 2 9X。结论 :当用 2 ,6 -二氯酚靛酚法测定绿豆和黄豆芽中的维生素 C时 ,其误差较大。但对于尿中维生素 C,如果使用 2 ,6 -二氯酚靛酚法 ,则须用回归方程进行推断  相似文献   
4.
蔬菜中氨基甲酸酯类农药残留的HPLC/MS测定研究   总被引:11,自引:4,他引:11  
目的建立简便、灵敏、准确的高效液相色谱电喷雾质谱测定蔬菜中氨基甲酸酯残留的检测方法.方法样品经乙腈提取、甲醇二氯甲烷(199 v/v)溶解后,用固相萃取小柱进行净化、提纯.选用Pickering C8(250 mm×4.0 mm×5 μm)作为分析柱,甲醇/酸化水(内含0.1%乙酸)梯度洗脱,通过选择性离子监测(SIM)及电喷雾电离离子化技术进行测定.结果线性范围为50.0~1 500.0μg/L,定量检测下限为4.8~8.6μg/kg,方法回收率为78.5%~108.4%,标准偏差为4.6%~7.9%,RSD均小于8%.结论该法灵敏度高、操作简便、快速,适用于实际样品的测定.  相似文献   
5.
2003~2004年苍山县部分蔬菜农药残留量检测分析   总被引:2,自引:0,他引:2  
[目的]了解苍山县蔬菜农药残留有关情况,为有效控制蔬菜农药残留,提供科学依据.[方法]2003~2004年对苍山县部分蔬菜批发市场、种植基地及零散摊点进行随机抽样检测,用农药速测卡结合色谱法测定其中的有机磷类农药.[结果]共检测各种蔬菜827份,农药残留阳性的98份,阳性率为11.85%.[结论]我县蔬菜农药残留问题比较严重,应进一步加强监督管理.  相似文献   
6.
7.
目前,很多植物类的产品对人体免疫系统的效能起了很大的作用,由此诞生了营养免疫学这样的学科。以蔬果类作为人体免疫系统活化剂和稳定剂,探讨其对免疫系统的作用。  相似文献   
8.

Objectives

Short ramie fibers were selected to investigate the effect of fiber length and volume fraction on the flexural properties of ramie fiber reinforced denture base PMMA. With the aid of measured interfacial shear strength and theoretical prediction values, experimental results were well interpreted.

Methods

Interfacial properties between denture base PMMA and ramie fibers were evaluated by single fiber pull-out test. Then, chopped ramie fibers were pre-stirred with PMMA powder by a mechanical blender and then mixed with MMA liquid to fabricate composites. Two crucial influencing factors, fiber volume fraction and fiber length, were studied to clarify their effects on flexural properties of composites.

Results

With 1.5 mm fibers addition, flexural modulus of denture base PMMA rose from 2.50 to 3.46 GPa with 10 vol.% fibers, while flexural strength declined steadily with increment of fiber content. If fiber length was 3.0 mm, the modulus showed a growth to 3.5 GPa at 4 vol.% fiber content followed by a drop to 3.00 GPa at 10 vol.%, whereas fluctuation in strength was experienced. Experimental results were discussed by comparison with two theoretical models.

Significance

Short ramie fiber reinforced denture base PMMA had higher flexural modulus than neat resin, while strength was lowered due to the weak interfacial adhesion. The potential of vegetable fibers as reinforcing agents for denture base should be further investigated by strengthening the interface between cellulose and denture base PMMA.  相似文献   
9.

Objectives

The number of teeth has frequently been used as an indicator of oral health in investigations of food intake; however, this measure does not represent the efficacy of the masticatory performance. Masticatory performance may be more important for food selection and avoidance than number of remaining teeth. The aim of this study was to investigate the association of occlusal force with habitual dietary intakes in independently living older Japanese.

Methods

The study population was 757 community-dwelling people aged 69–71 years old. Bilateral maximal occlusal force in the intercuspal position was measured with pressure-sensitive sheets. Removable denture wearers kept their dentures in place during the measurements. Dietary habits during the preceding month were assessed using a brief-type self-administered diet history questionnaire that measures consumption frequencies of selected food commonly consumed and calculates energy-adjusted dietary intakes. Linear trends of food and nutrient intakes with decreasing occlusal force were tested after adjusting for gender and socioeconomic factors.

Results

After adjusting for socioeconomic status and the number of remaining teeth, decline of occlusal force was significantly associated with lower intakes of vegetables, vitamins A, C, B6, folate, and dietary fibre (P for trend < 0.05). In contrast, number of teeth was significantly associated only with calcium and zinc, controlling for occlusal force.

Conclusions

It is concluded that occlusal force was significantly associated with intakes of vitamins and dietary fibre rather than number of remaining teeth in independently living older Japanese.  相似文献   
10.
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