高明市2389名0—6岁儿童锌,铁,铜,钙缺乏状况调查

调查了高明市２３８９名０￣６岁儿童锌、铁、铜、钙缺乏状况。结果表明，本市儿童缺锌、铜、铁和钙各为４５．９２％，６０．２０％，１３．４４％和４．６０％。讨论了缺锌、铜、铁的原因。     

推广使用无铅汽油对儿童血铅水平影响的研究

于１９９７年７月－９月在上海市５个区县３０所幼托机构对１９７２名１－６岁儿童进行了血铅水平抽样调查,然后于上海地区推广使用无铅汽油半年后的１９９８年４－６月相应人群进行血铅水平复查。     

The role of iron and zinc in chemotherapy-induced alopecia

Chemotherapy-induced alopecia is a common and distressing side effect in children with cancer. Iron and zinc are the well known trace elements which are associated with hair shedding. In this study, we investigated the hair content of iron and zinc in children with cancer consists of two groups: group A, newly diagnosed patients; group B, the patients received a course of chemotherapy. We compared the results between each others and healthy controls. Hair content of iron and zinc was not different between the patient groups. Iron concentrations of patient samples, either at diagnosis or after chemotherapy, were significantly lower than healthy controls. However, there was no statistically significant difference between the groups regarding the zinc values. In conclusion, hair content of iron and zinc do not have a role in chemotherapy-induced alopecia.     

Spatial regression analysis between air pollution and childhood leukaemia in Portugal

This study aims to investigate whether known carcinogenic chemical elements in atmospheric deposition might be associated with child mortality due to leukemia in the Portuguese population. A Bayesian hierarchical model was used to explore the association between lichen biomonitoring measurements of four elements—As, Hg, Ni, Pb—and childhood leukemia death counts taken at small administrative units. This geographical epidemiological study found a non-significant positive association between the risk of childhood leukemia and levels of arsenic, mercury and lead, and a non-significant negative association between the disease and the level of nickel. Lead seems to show a weaker association with childhood leukemia than arsenic and mercury.     

深圳市626例儿童发铅含量调查

报道了深圳市６２６名１￣７岁儿童头发中铅的含量，有２７９名儿童可能有慢性铅中毒的危险，占儿童总数的４４．４１％。分析了产生儿童铅含量高的原因，并提出了切实可行的预防措施。     

儿童口服锌制剂合理配伍实验探讨

锌盐是微量元素的常用制剂，治疗范围广，疗效确切，生物学功能作用独特，但锌盐口服时，常引起食欲减退、恶心、呕吐、腹痛和白细胞减少症等副作用，尤以儿童反应为甚。     

高效液相色谱-串联质谱法测定儿童和成人尿液中双酚A、四溴双酚A和辛基酚

采用高效液相色谱-串联质谱法定量检测人体尿液中痕量双酚A、四溴双酚A和辛基酚.将解冻后的尿样酶解,经液液萃取、旋蒸至干,甲醇定容后分析.3种目标物质在0.2～50 μg/L质量浓度范围内线性关系良好,相关系数均大于0.99,定量限(LOQ)在0.05 ～ 0.27 μg/L之间.在5,10和50 μg/L加标水平下,平均回收率为85.7％～118.6％,相对标准偏差RSD(n=3)为4.1％ ～10.5％.20组儿童与成人的尿样结果表明,尿样中均检出3种目标物,其中,四溴双酚A和辛基酚在儿童及成人尿样中的暴露浓度基本相同,但是双酚A的暴露水平具有显著性差异(儿童＞成人).     

Integer comparisons across the grades: Students’ justifications and ways of reasoning

This study is an investigation of students’ reasoning about integer comparisons—a topic that is often counterintuitive for students because negative numbers of smaller absolute value are considered greater (e.g., −5 > − 6). We posed integer-comparison tasks to 40 students each in Grades 2, 4, and 7, as well as to 11th graders on a successful mathematics track. We coded for correctness and for students’ justifications, which we categorized in terms of 3 ways of reasoning: magnitude-based, order-based, and developmental/other. The 7th graders used order-based reasoning more often than did the younger students, and it more often led to correct answers; however, the college-track 11th graders, who responded correctly to almost every problem, used a more balanced distribution of order- and magnitude-based reasoning. We present a framework for students’ ways of reasoning about integer comparisons, report performance trends, rank integer-comparison tasks by relative difficulty, and discuss implications for integer instruction.     

Evolution of Vocal Fold Nodules from Childhood to Adolescence

SUMMARY: Bilateral (quasi) symmetrical lesions of the anterior third of the vocal folds, commonly called vocal fold nodules (VFNs) are the most frequent vocal fold lesions in childhood caused by vocal abuse and hyperfunction. This study evaluates their long-term genesis with or without surgery and voice therapy. A group of 91 postmutational adolescents (mean age, 16 years), in whom VFNs were diagnosed in childhood, were questioned to analyze the evolution of their complaints. Thirty four of them could be clinically reexamined by means of the European Laryngological Society-protocol, including a complete laryngological investigation and voice assessment. A total of 21% of the questioned group (n=91) had voice complaints persisting into postpubescence with a statistically significant difference (P 相似文献