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81.
Wanji S Tanke T Atanga SN Ajonina C Nicholas T Fontenille D 《Tropical medicine & international health : TM & IH》2003,8(7):643-649
There is a lack of data on the Anopheles fauna, its biology and the roles played by different vector species in the transmission of malaria in the mount Cameroon region. The biting habits, feeding behaviour and entomological inoculation rates of different Anopheles species during the dry and rainy season were investigated. A total of 2165 Anopheles was collected, 805 in the rainy season and 1360 in the dry season. Five Anopheles species were identified: Anopheles gambiae s.l., An. funestus, An. hancocki, An. moucheti and An. nili. An. gambiae, An. funestus and An. hancocki, recorded during both seasons, were the main vectors of malaria in the region. An. gambiae s.s. was the only member of the An. gambiae (Giles) complex. These three species had their peak activity between 1 and 2 am. A human blood index (HBI) of 98.29% was recorded for fed Anopheles. The sporozoite rate, for all vectors together, was significantly higher in the rainy season (9.4%) than in the dry season (4.2%) with all the species infected by Plasmodium falciparum. The average inoculation rate was 0.44 infective bites per man per night, which adds up to 161 infective bites per year in this study area. Analyses of relative abundance and infection rate of malaria vectors at different sites situated along a transect of 20 km during the dry season showed high heterogeneity in biting and sporozoite rates. No malaria vector was caught at 1200 m a.s.l. The mount Cameroon region should be considered an area of high malaria transmission intensity. 相似文献
82.
Spatial bias may occur in subjects performing a number of cognitive and visual-motor tasks. These include coordinate visuospatial computations (e.g. bisecting a line) and categorical representations of syntactic information (e.g. drawing a picture depicting the action of a sentence). Readers of European languages scan from left-to-right and this learned visual scanning may contribute to leftward spatial bias. In 30 subjects who first learned to read in a top-to-bottom, right-to-left direction (right-left vertical readers, RL), we tested spatial-syntactic bias by reading sentences to subjects, who drew pictures depicting the actions. We noted whether the subject of the sentence was located leftward or rightward of the object. We assessed visual-spatial bias by measuring subjects' accuracy at bisecting lines, and by measuring how closely their drawings on the house-tree-person test were centered on the page. On the spatial-syntactic task, the RL were not right- or left-biased (P=0.581). Korean controls (left-right horizontal readers, LR) also showed no significant spatial-syntactic bias. RL only tended to bisect lines leftward, but displaced house-tree-person drawings left of page center (P<0.001). LR erred leftward on line bisection, and had a smaller magnitude leftward bias on drawing tasks. We conclude that a leftward spatial-syntactic bias may not be innate and does not appear to be influenced by learned reading direction. In contrast, the leftward visual-spatial bias may occur in subjects whose cultural and reading background is neither western nor left-to-right. 相似文献
83.
Contributions of the home literacy environment to preschool-aged children's emerging literacy and language skills 总被引:1,自引:0,他引:1
Daniel J. Weigel Sally S. Martin Kymberley K. Bennett 《Early child development and care》2006,176(3):357-378
This paper reports on a study that examined both the concurrent and logitudinal connections between multiple components of the home environment and indicators of preschool-aged children's literacy and language development. Data were collected from 85 parents and their children at two different times. Results of structural path models indicated that (a) parental literacy habits were positively associated with parental reading beliefs, (b) parental reading beliefs were positively associated with parent-child literacy and language activities in the home, and (c) parent-child literacy and language activities were positively associated with children's print knowledge and reading interest. Parental demographic characteristics were associated with children's expressive and receptive language skills. The results highlight how different components of the home literacy environment are associated with different components of preschool-aged children's literacy and language abilities, findings that become more important as educators and policy-makers look for ways to enhance children's literacy and language development. 相似文献
84.
目的研究SARS应激下人们应对策略的特点及其在人们生活行为习惯变化中的作用。方法采用网络问卷调查的方式,使用应对策略量表和针对SARS自编的行为习惯变化问卷,对388名被试进行了调查。结果在SARS应激下,人们普遍以问题中心策略应对(P=0.00),并倾向于采取问题解决策略(P=0.00),这种倾向没有性别差异;人们的行为习惯发生了很大的变化(P<0.001),但行为习惯的变化没有发现与应对策略有对应关系。结论SARS应激下,人们更多采取了问题解决的应对策略,不同策略对人们的生活行为习惯改变影响不大。 相似文献
85.
家长营养知识和态度对子女饮食行为的影响 总被引:9,自引:2,他引:9
目的了解家长营养知识和态度对子女饮食行为的影响程度,为有针对性地对其进行营养教育提供科学依据。方法采用问卷调查法对深圳市300名学龄儿童及其家长进行营养知识、态度、行为的调查。结果家长对儿童营养知识普遍缺乏,大部分学龄儿童存在着不同程度的各种不良饮食习惯,如不吃早餐、吃零食、挑食、偏食、进食速度过快和膳食搭配不合理等。结论家长的营养知识和态度对子女饮食行为和食物消费结构有明显影响;但家长和学生接受营养知识的态度较好,说明在家长和学生中开展有针对性地营养健康教育是非常必要和可行的。 相似文献
86.
吉林市2所小学学生单纯性肥胖的影响因素 总被引:1,自引:0,他引:1
目的 了解与小学生单纯性肥胖有关的影响因素,为进一步实施干预提供依据。方法采用自行设计的问卷结合体格检查对吉林市2所小学354名学生进行调查。筛选出单纯性肥胖学生43名,同时选出与肥胖儿童同班、同性别、身高相差在3cm内,出生年月相差在3个月内,而身高标准体重为正常的学生43名作为对照。结果与对照组比较,肥胖组父母至少一方肥胖者人数显著高于对照组;肥胖组的饮食行为问题有:进食速度快,睡前进食,看电视时进食等;运动行为问题有:看电视时间长,每天运动时间少,不喜欢体育运动等。在发中微量元素含量的测定中肥胖组发中铬、铅含量高于对照组。结论遗传和环境因素均与儿童单纯性肥胖症有关,防治肥胖应从改变不良的饮食和运动行为着手。 相似文献
87.
A follow-up study of serum ferritin and transferrin receptor concentrations in Swedish adolescents at age 17 age 15 总被引:1,自引:0,他引:1
Samuelson G Lönnerdal B Kempe B Elverby JE Bratteby LE 《Acta paediatrica (Oslo, Norway : 1992)》2000,89(10):1162-1168
Serum ferritin and serum transferrin receptor concentrations, growth and food habits were studied in healthy Swedish boys (n = 103) and girls (n = 124) at the age of 17 y and compared with those in the same adolescents at age 15. Between these ages, serum transferrin receptor increased significantly in both boys and girls. Serum ferritin increased significantly in boys but not in girls. The transferrin receptor/ferritin ratio increased significantly in girls but not in boys, indicating insufficient iron stores in the 17-y-old girls in relation to erythropoiesis and iron needs. Between 15 and 17 y the boys' frequency of consumption of milk and bread decreased, while they more often consumed pasta, cheese and coffee. The girls decreased their frequency intake of fat products, milk and meat. The frequency of meat consumption emerged as the single significant predictor for serum ferritin <12 microg/L in girls, but not in boys. The median daily iron intake, determined in a subsample, decreased in boys from 18.7 to 13.6 mg and in girls from 14.1 to 8.8 mg, and the decrease was to a large extent due to cessation of iron fortification of flour. CONCLUSIONS: The results indicate insufficient iron stores in the 17-y-old girls in relation to erythropoiesis and iron needs, but more favourable iron stores in the boys. The absence of a significant decrease in mean serum ferritin despite rapid growth suggests that the earlier iron fortification of flour only marginally contributed to the iron status of Swedish adolescents of this age group. 相似文献
88.
[背景]探讨营养指导对妊娠性糖尿病(GDM)孕妇血糖控制及巨大儿发生率的影响.[病例报告]对240名孕妇进行50 g糖筛查试验,对异常者进行75 g糖筛查试验,对GDM及糖耐量低下孕妇行个体化营养指导及血糖监测.240名孕妇中糖筛查异常者为62名(25.8%),GDM孕妇为17例(7.1%),糖耐量低下孕妇为16例(6.5%),巨大儿发生率为7.8%.17例GDM孕妇所产婴儿中巨大儿发生例数为7例.[讨论]合理的营养指导可有效地控制GDM孕妇血糖,降低巨大儿的发生率. 相似文献
89.
Uruwan Yamborisut Pongtorn Sungpuag Wanphen Wimonpeerapattana 《Pediatrics international》2008,50(4):557-562
Background: There is evidence to show that atherosclerosis can occur in young children and that elevated total cholesterol and low density lipoprotein cholesterol concentrations are risk factors for atherosclerosis. The aim of the present cross-sectional study was to investigate the influence of maternal and nutritional factors on blood cholesterol in primary school children.
Methods: One hundred and ninety-five population-based mother–child pairs (obese child–overweight mother pairs, n = 60; obese child–normal-weight mother pairs, n = 48; wasted child–overweight mother pairs, n = 37; normal-weight child–normal-weight mother pairs, n = 50), were enrolled in the study. Various anthropometric parameters were measured and serum lipids of subjects were further determined. Biological data and children's eating behavior were obtained from the mothers through interviews.
Results: Hypercholesterolemia was found in 64.6–65% of obese children, 24.3% of wasted children and in 56% of the normal-weight children; whereas the proportion of children in all groups who had normal blood cholesterol levels was in the lower range. Multivariate logistic regression indicated that mother's serum cholesterol (odds ratio [OR], 2.41; 95% confidence interval [CI]: 1.12–4.78), child obesity defined by weight-for-height Z-score > +2SD (OR, 2.56; 95%CI: 1.33–4.98), and child's energy intake ≥75th percentile (OR, 2.59; 95%CI: 1.01–6.66) were the significant factors associated with hypercholesterolemia in children.
Conclusion: Hypercholesterolemia in school children is associated with familial factor, bodyweight and nutrient intake. Elevated blood cholesterol was also found in some of the normal-weight and wasted children. Effective family-based intervention programs are urgently needed to modify risk factors predisposing to coronary heart disease. 相似文献
Methods: One hundred and ninety-five population-based mother–child pairs (obese child–overweight mother pairs, n = 60; obese child–normal-weight mother pairs, n = 48; wasted child–overweight mother pairs, n = 37; normal-weight child–normal-weight mother pairs, n = 50), were enrolled in the study. Various anthropometric parameters were measured and serum lipids of subjects were further determined. Biological data and children's eating behavior were obtained from the mothers through interviews.
Results: Hypercholesterolemia was found in 64.6–65% of obese children, 24.3% of wasted children and in 56% of the normal-weight children; whereas the proportion of children in all groups who had normal blood cholesterol levels was in the lower range. Multivariate logistic regression indicated that mother's serum cholesterol (odds ratio [OR], 2.41; 95% confidence interval [CI]: 1.12–4.78), child obesity defined by weight-for-height Z-score > +2SD (OR, 2.56; 95%CI: 1.33–4.98), and child's energy intake ≥75th percentile (OR, 2.59; 95%CI: 1.01–6.66) were the significant factors associated with hypercholesterolemia in children.
Conclusion: Hypercholesterolemia in school children is associated with familial factor, bodyweight and nutrient intake. Elevated blood cholesterol was also found in some of the normal-weight and wasted children. Effective family-based intervention programs are urgently needed to modify risk factors predisposing to coronary heart disease. 相似文献
90.
大学生营养知识和饮食习惯现状调查 总被引:1,自引:0,他引:1
目的了解大学生营养知识与饮食习惯现况,为提高大学生健康水平提供依据。方法对198名在校大学生进行了问卷调查。问卷涉及日常饮食、饮食习惯、营养知识、饮食态度等4个方面。结果59.1%的学生经常吃早餐,14.6%的学生偶尔吃早餐,26.3%的学生几乎不吃早餐,经常吃早餐者的比例女生高于男生,差异有统计学意义(X^2=14.007,p〈0.05);饮食习惯则过多地食用方便面、油炸食品、腌酱菜食品、火腿肠,只有7.5%的大学生不摄取这4种食品;而吃鱼、牛奶、蔬菜的比例较低,分别占43.0%、16.6%、59.1%。在男生中存在喝酒等不良习惯者高于女生,差异有统计学意义(X^2=14.521,p〈0.05);学生普遍缺乏对营养知识的了解;70.2%的学生以“口味”作为首选食物标准,仅18.7%选择“营养”。结论学生营养知识和饮食习惯存在较多问题,应加强大学生营养知识的教育,纠正其不合理的饮食习惯。 相似文献