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BACKGROUND: This paper describes the development of the UK Women's Cohort Study and presents cohort baseline characteristics. METHODS: In total, 35,372 women, aged 35-69 years at recruitment, were selected to ensure a wide range of dietary intakes. Diet was assessed by a 217-item food-frequency questionnaire (FFQ). Detailed lifestyle information was collected by postal questionnaire. Vegetarians, fish-eaters and meat-eaters were compared. RESULTS: The cohort women are mainly white, well-educated, middle-class and married with children. They are health-conscious with only 11% current smokers and 58% taking dietary supplements. Twenty-eight per cent of subjects self-report as being vegetarian and 1% as vegan. However, only 18% are defined as 'vegetarian' from the FFQ. Fat provides 32% of energy; vitamin and mineral intakes are high, with a broad range of intakes. Meat-eaters are older, with a higher body mass index (BMI) and the lowest intakes of carbohydrate, fibre, vitamin C, folate, iron and calcium. Other fish-eaters are similar to vegetarians. Vegetarians have the lowest intakes of protein, fat and saturated fat. Oily fish-eaters have the lowest BMI; are the least likely to smoke or use full-fat milk; and are the most likely to use dietary supplements and consume the most fruit and vegetables. Oily fish-eaters have the highest total energy intake and vegetarians the lowest. Semi-skimmed milk, bread, potatoes, wine, bananas and muesli are important contributors to energy for all groups. CONCLUSION: A large cohort of middle-aged women has been created encompassing a wide range of different eating patterns, including diets currently of interest to research into protection against cancer and coronary heart disease. Participants will be followed up to study the effects of different food and nutrient intakes on long-term health outcomes.  相似文献   

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OBJECTIVE: To evaluate the current status of dietary intakes in early pubertal girls with a special focus on milk products. DESIGN: Cross-sectional data using 3-day food records. SUBJECTS: Eight hundred and sixty girls, aged 10-12 years, at Tanner maturation stage I-III. RESULTS: The mean consumption of milk products (620 g day(-1)) was similar to that of a Finnish study in the 1980s, while the consumption of non-milk drinks (403 g day(-1)) had increased. Twelve per cent of the girls had a dairy-restricted diet and consumed significantly less milk products than girls with a non-restricted diet (465 vs. 644 g day(-1), P<0.001). Girls with low milk product consumption had the highest non-milk drinks consumption (P<0.001). The mean energy intake was 7.1 MJ day(-1). No major changes were found in the sources of nutrients. The shares of energy for nutrients were close to recommendations except for saturated fat (13.9 vs. 10% of energy) and carbohydrates (51.5 vs. 55-60% of energy). The mean calcium intake (1117 mg day(-1)) was above the recommendation, while the vitamin D intake (3.1 microg day(-1)) of 88% of the girls was below the recommendation. CONCLUSIONS: The diet quality of early pubertal girls is close to the recommendations and has improved with respect to fat compared with the 1980s. Consumption of milk products is high although the consumption of non-milk drinks has increased. We found a subgroup of girls who compensate their low milk product consumption with a higher consumption of non-milk drinks. Following a dairy-restricted diet is the main reason for low consumption of milk products.  相似文献   

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OBJECTIVES: To examine the contribution of the food service sector to the nutrient quality of the Irish diet, and to compare intakes at home, work and outside the home ('out') and within the subgroups of the out location (pub, deli, takeaway). DESIGN AND SETTING: Random sample of adults from the Republic of Ireland. Food intake data were collected using a 7-day food diary. Respondents recorded the location of every eating occasion determined by where the food was prepared rather than consumed. RESULTS: Intakes of energy, protein, fat and carbohydrate were significantly greater at home than at work or out (P<0.05). The intake of alcohol was significantly (P<0.001) greater out than at home or work. The percentage contribution of fat to energy was above the recommendations (33% of total energy and 35% of food energy) for both men and women at all locations, with the exception of the contribution of fat to total energy for men at the out location. Within the subgroups of the out location, the contribution of alcohol to total energy was greatest in pubs and the contribution of fat to both total and food energy was greatest in takeaways. Intakes of fibre and most micronutrients per 10 MJ of food energy were greater (P<0.05) at home than at work or out. CONCLUSION: Foods eaten outside the home contribute a disproportionately high level of fat intake and should be targeted in public health nutrition strategies.  相似文献   

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在河北省不同区域棉区选择代表县市,通过调查分析和氮、磷、钾3414试验的方法,研究冀南棉区、冀中南棉区及滨海盐渍土棉区的土壤氮、磷、钾养分丰缺现状和养分管理技术。结果表明:冀南棉区土壤速效钾含量偏低成为本区域的制约因素,养分调控原则为稳氮、补磷、増钾,N、P2O5、K2O适宜用量分别为135、110、150 kg/hm2,专用肥适宜配方为15-13-17;冀中南棉区土壤速效养分含量较为均衡,养分调控原则为稳氮、稳磷、补钾,N、P2O5、K2O适宜用量分别为140、90、120 kg/hm2,专用肥适宜配方为18-12-15;滨海盐渍土棉区土壤养分含量极度不平衡,土壤有效磷含量极低、速效钾含量很高,养分调控原则为控氮、增磷、控钾,N、P2O5、K2O适宜用量分别为135、130、90 kg/hm2,专用肥适宜配方为17-16-12。  相似文献   

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OBJECTIVE: To assess tracking of energy and nutrient intakes between adolescence and young adulthood. DESIGN: Longitudinal study of a random sample of adolescents (aged 15 years at baseline). The extent of tracking of dietary intakes (assessed by diet history) was investigated using weighted kappa statistics (kappa). SETTING: Northern Ireland population survey. SUBJECTS: Adolescents who participated in the Young Hearts Project, Northern Ireland at age 15 years, and subsequently at young adulthood aged between 20 and 25 years (n=245 males, n=231 females). RESULTS: Despite overall increases in height and weight (both P<0.001), increases in body mass index in males (P<0.001) and body fatness in females (P<0.001), median reported intakes of energy (kJ kg(-1) day(-1)), carbohydrate (g day(-1)) and fat (g day(-1)) decreased (all P<0.001) over time. Expressed as nutrient densities (per MJ), diets at young adulthood were overall richer in thiamin, vitamin B6, total folate (all P<0.001), vitamin C (P<0.01) and vitamin D (P<0.05). Whereas the nutrient density of the males' diets decreased over time for calcium (P<0.05) and vitamin A (P<0.001), iron and riboflavin densities increased in the females' diet (P<0.001). Tracking of energy (MJ day(-1)) and nutrient intakes (expressed per MJ day(-1)) at the individual level was only poor to fair (all kappa<0.25), indicating substantial drift of subjects between the low, medium and high classes of intake with increasing age. CONCLUSIONS: These data suggest that individual dietary patterns exhibited at 15 years of age are unlikely to be predictive of dietary intakes at young adulthood.  相似文献   

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OBJECTIVES: To undertake secondary analyses of the 1997 National Diet and Nutrition Survey of Young People aged 4-18 years in order to describe the contribution of school meals to daily food and nutrient intakes; and to compare the findings from 1997 with data collected in English primary and secondary schools in 2004-2005. DESIGN: Cross-sectional analysis of 7-day weighed inventory food consumption data according to age, sex, household income, free school meals and breakfast consumption. Comparison of food consumption with the Balance of Good Health and of nutrient intake data with the Caroline Walker Trust (CWT) guidelines. SETTING: United Kingdom. SUBJECTS: One thousand four hundred and fifty-six UK schoolchildren aged 4-18 years, 7058 English primary-school pupils and 5695 English secondary-school pupils. RESULTS: Pupils' school meal choices in 1997 did not accord with the Balance of Good Health. Food choices in school were less healthy than choices outside school. School meals failed to make good the shortfalls in daily intakes of non-starch polysaccharides and zinc in primary-school pupils, and of calcium, iron, zinc, vitamin A and non-starch polysaccharides in secondary-school pupils, nor excess daily intakes of saturated fatty acids, non-milk extrinsic sugars and sodium at all ages. School meals typically failed to meet CWT guidelines. They were more likely to meet CWT guidelines when choice of foods was restricted. CONCLUSIONS: School meals need substantial improvement to meet CWT guidelines for healthy eating. The introduction of food-based guidelines for school meals in England in 2001 did not improve the food choices in school meals.  相似文献   

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OBJECTIVE: To assess validity of the Nambour food-frequency questionnaire (FFQ) relative to weighed food records (WFRs), and the extent to which selected demographic, anthropometric and social characteristics explain differences between the two dietary methods.DESIGN: Inter-method validity study; 129-item FFQ vs. 12 days of WFR over 12 months.SETTING: Community-based Nambour Skin Cancer Prevention Trial.SUBJECTS: One hundred and fifteen of 168 randomly selected participants in the trial (68% acceptance rate) aged 25-75 years.RESULTS: Spearman correlations between intakes from the two methods ranged from 0.18 to 0.71 for energy-adjusted values. Differences between FFQ and WFR regressed on personal characteristics were significantly associated with at least one characteristic for 16 of the 21 nutrients. Sex was significantly associated with differences for nine nutrients; body mass index (BMI), presence of any medical condition and age were each significantly associated with differences for three to six nutrients; use of dietary supplements and occupation were associated with differences for one nutrient each. There was no consistency in the direction of the significant associations. Regression models explained from 7% (riboflavin) to 27% (saturated fat) of variation in differences in intakes.CONCLUSIONS: The relative validity of FFQ estimates for many nutrients is quite different for males than for females. Age, BMI, medical condition and level of intake were also associated with relative validity for some nutrients, resulting in the need to adjust intakes estimates for these in modelling diet-disease relationships. Estimates for cholesterol, beta-carotene equivalents, retinol equivalents, thiamine, riboflavin and calcium would not benefit from this.  相似文献   

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河西走廊制种田与生产田玉米需肥特点比较   总被引:4,自引:0,他引:4  
河西走廊是全国最大的玉米制种基地,但存在制种玉米超量滥施化肥问题。因此,采用田间试验和室内样品分析相结合的方法,以同一组合杂交种玉米生产试验田作对照,研究了自交系玉米制种田氮、 磷、 钾需肥量及需肥特点。结果表明, 制种田玉米种子产量明显小于生产田玉米,制种田子粒产量是生产田的0.6114倍; 制种田全生育期氮、 磷、 钾吸收量均小于生产田,分别是生产田的0.738倍、 0.624倍、 0.733倍; 生产百公斤玉米种子吸收氮(N)、 磷(P2O5)、 钾(K2O)养分平均为2.653 kg、 1.115 kg和3.447 kg; N∶P2O5∶K2O比例为1∶0.42∶1.30。养分累积进程也不同,苗期养分吸收量制种田大于生产田,拔节期相近,拔节后制种田均小于生产田,养分累积量平均为生产田的63.0%~85.3%。因此,相比生产玉米,制种玉米应适当减少施肥量,并增加苗期养分供应。  相似文献   

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烤烟苗期营养特性的基因型差异及其杂种优势分析   总被引:1,自引:0,他引:1  
试验选用6个杂交烤烟组合共13种基因型,研究了苗期营养特性的差异,并分析F1代烟苗营养特性与亲本之间的相关性和杂种优势。结果表明: 1)不同基因型烟苗的生物量、 根冠比、 养分(氮、 磷、 钾)含量和吸收量、 硝酸还原酶活性、 叶绿素含量、 根系活力差异显著,表现出多样性; 2)在F1代烟苗中,根系氮、 磷、 钾和地上部氮、 钾含量,以及干物质积累量、 根系活力和根冠比与父本和母本值之间相关性不显著,地上部磷含量与中亲值之间呈显著负相关,叶片硝酸还原酶活性与母本值之间呈显著正相关,叶绿素含量与父本值、 中亲值和低亲值之间呈极显著正相关; 3)烟苗根系磷、 钾含量、 地上部氮含量、 硝酸还原酶活性、 叶绿素含量、 根系活力、 根冠比、 干物质积累量具有一定的中亲优势。根系磷含量、 硝酸还原酶活性、 根系活力、 根冠比和干物质积累量具有超高亲优势。尽管根系氮含量和地上部磷、 钾含量无明显杂种优势,但有的试验组合也表现出中亲优势和超高亲优势。  相似文献   

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河北省滨海盐碱地土壤与盐生植物养分特征的研究   总被引:11,自引:2,他引:11       下载免费PDF全文
对滨海盐碱地土壤和植物样品分析结果表明,生长不同盐生植物的土壤含盐量不同,以生长白刺(Nitraria sibirica Pall.)的土壤含盐量最高,达18.5 g/kg,盐地碱蓬(Suaeda salsa L.Pall.)次之,柽柳的最低。盐生植物的生长改变了土壤养分特征,4种生长盐生植物的土壤养分含量均高于光板地,土壤有机质含量增加44%以上,生长木本盐生植物白刺、柽柳(Tamarix chinensis Lour.)的土壤养分含量高于生长草本盐生植物碱蓬、碱茅(Puccinellia distans Jacq.Parl.)的土壤,且不同盐生植物养分特征不同,白刺、柽柳N和P含量均高于盐地碱蓬、碱茅,K含量则与植物耐盐特性有关。  相似文献   

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农业生产系统存在秸秆养分释放与作物生长需求匹配程度低等问题,拟通过腐熟剂用量调节还田小麦秸秆腐解及养分释放率,使之与作物生长需求相吻合,进而提升夏玉米产量。以人元腐熟剂为供试腐熟剂,小麦秸秆为供试秸秆,郑单958为供试玉米品种。采用完全随机区组试验设计,设置4种腐熟剂施用量:30 kg/hm2(T1)、45 kg/hm2(T2)、60 kg/hm2(T3)、75 kg/hm2(T4),以不施腐熟剂为对照(CK)。测定秸秆腐解率、养分释放率、夏玉米关键生育期的株高、茎粗、生物量和作物产量,通过回归分析探究秸秆养分阶段性释放如何调控夏玉米生长及籽粒产量形成。腐熟剂用量为45 kg/hm2时,秸秆最终腐解率可达69.28%。腐熟剂用量对不同养分释放的调控效果不同,其中,氮和有机碳的释放率呈线性变化,磷和钾的释放率呈阶段性变化。腐熟剂施用对抽雄期(VT)各养分释放率均有显著的促进效应。三叶期(V3)较CK而言,T2和T4处理氮、磷释放率增幅分别达到203.67%、187.05%和17....  相似文献   

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