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61.
Abstract

A sudden increase in serum creatinine after paraquat intoxication has been reported in several clinical studies. However, this dramatic change of creatinine may be possibly due to an interconversion of creatine-creatinine in relation to paraquat toxicity. In order to investigate the creatine-creatinine relationship, a liquid chromatography tandem mass spectrometry in combination with electrospray ionization was developed and validated for simultaneous determination of creatine and creatinine in the serum. The chromatographic separation was achieved on a Gemini® C6-Phenyl column with a gradient elution consisting of 0.1% formic acid in ultrapure water and methanol as the mobile phase. The method yielded suitable levels of specificity and selectivity, and calibration curves of creatine and creatinine in serum were linear over the concentration range of 0.5–200?µg mL?1. The limit of quantification of both compounds was 0.5?µg mL?1, and the method was accurate within the recovery range of 96.23–102.75%, indicating the robustness of the method. The method was successfully applied to toxicological samples from paraquat-intoxicated patients, and the concentrations of creatine and creatinine were quantified. High creatine concentrations in serum samples were observed which may lead to high serum creatinine despite normal kidney function as creatine is converted to creatinine in proportion to its concentration.  相似文献   
62.
INTRODUCTION: We report the first evaluation of the popular "Cyrus the Centipede" child pedestrian safety program. METHOD: A pre-test/post-test control versus experimental condition design was used to assess Cyrus' impact on third graders' pedestrian safety knowledge, and self-reported pedestrian behaviors. RESULTS: Although some beneficial effects were observed, the program was not reliably effective. In particular, the impact of exposure to Cyrus was strongly influenced by the individual teacher who delivered it, likely due to the highly unstructured nature of the curriculum. SUMMARY: We suggest that: (a) the effectiveness and reliability of such programs be demonstrated before they are widely adopted; and (b) programs that focus on training children in actual or simulated traffic environments may be more effective than those that primarily focus on teaching safety facts and rules.  相似文献   
63.
Objective: Motor vehicle accidents, which are among the main causes of child mortality in Iran and the Middle East, impose staggering costs for the community. Ignoring use of safety devices for children in most motor vehicle crashes will lead to death or serious injury. Because few studies have been performed on effective and predictive factors regarding use of child safety seats, the purpose of this study was to examine the factors affecting the use and nonuse of child safety seats, along with the factors that can facilitate how a child safety seat is used.

Method: This study was conducted in the urban area of Gorgan using a questionnaire. Through random selection, 204 parents with at least one child, aged 8?years or younger, reported their knowledge about the benefits of using a child safety seat.

Results: The results showed that 80% of parents never use a child safety seat, and 13% always use a child safety seat. More than 93% thought that it was necessary to make usage of the child safety seat obligatory. In addition, 80% of parents believed that a child safety seat prevents children from injury in crashes. In addition, 38% of parents were not aware of child safety devices and child safety, less than 20% said that they did not use a child safety seat because their spouse did not support its use, and 28% of them thought that a child safety seat does not affect the safety of the child. In general, 91% of parents reported that if child safety seat use were mandated, the frequency of use would increase. A law on the use of child safety seats is a very important variable in their use, which can enhance the chance of using a child safety seat by 6.5 times.

Conclusion: Special instructions should be developed to create incentive strategies for using a child safety seat. Mandating the use of a child safety seat, equipping cars with a child safety seat, encouraging children to use it, and providing continuous education and training are important factors for increasing the use of child safety seats.  相似文献   
64.
Introduction: Young workers are especially vulnerable to occupational injuries and illnesses. There is a continued need to investigate injury burden among young workers across demographics and industry to inform targeted interventions. Workers compensation (WC) claims are important for quantifying work-related injuries and illnesses, however published studies have focused on disabling claims. This study extended previous research on Oregon young workers by including the most recent WC claims data to identify patterns of injury and high risk industries. Methods: We obtained all accepted disabling claims (N = 13,360) and a significant portion of non-disabling claims (N = 24,660) on workers aged 24 years and under from 2013 to 2018. Claim count, rate and cost were calculated by year, age, gender, industry, and injury type. A prevention index (PI) method was used to rank industries in order to inform prevention efforts. Results: Average annual disabling and non-disabling claim rates were 111.6 and 401.3 per 10,000 young workers. Workers aged 19–21 (disabling: 119.0 per 10,000 and non-disabling: 429.3) and 22–24 years (115.7 and 396.4) and male workers (145.3 and 509.0) had higher claim rates than workers aged 14–18 (80.6 and 297.0) and female workers (79.8 and 282.9). The most frequent injury types were “struck by/against” (35.6%) and “work-related musculoskeletal disorders (WMSDs)” (19.5%). High risk industries included agriculture, construction, and manufacturing for both genders combined. For female young workers, the highest risk industry was healthcare. Conclusions: This study demonstrated the added value of non-disabling WC claims data. Using both disabling and non-disabling data and PI method, agriculture, construction, manufacturing and healthcare industries were identified as priority workplaces to prevent common and costly injuries among Oregon young workers. Practical Applications: While the industries identified are considered hazardous for all workers, findings in this study can guide targeted research and prevention efforts specific to young workers.  相似文献   
65.
This article presents an analysis of results of 1035 serious and 341 minor accidents recorded by Poland's National Labour Inspectorate (PIP) in 2005–2011, in view of their prevention by means of additional safety measures applied by machinery users. Since the analysis aimed at formulating principles for the application of technical safety measures, the analysed accidents should bear additional attributes: the type of machine operation, technical safety measures and the type of events causing injuries. The analysis proved that the executed tasks and injury-causing events were closely connected and there was a relation between casualty events and technical safety measures. In the case of tasks consisting of manual feeding and collecting materials, the injuries usually occur because of the rotating motion of tools or crushing due to a closing motion. Numerous accidents also happened in the course of supporting actions, like removing pollutants, correcting material position, cleaning, etc.  相似文献   
66.
东北玉米低温冷害监测预测系统——在黑龙江省的应用   总被引:2,自引:0,他引:2  
利用东北玉米低温冷害监测预测系统预测分析了黑龙江省1971-2006年各年热量年型,计算了哈尔滨市1984-2006年玉米抽雄期的冷害发生概率,同时采用以5-9月平均温度和的距平作为低温冷害指标的方法计算了1971-2006年低温冷害的发生状况.结果显示,上述两种方法计算得到的低温冷害的年份与历史实况基本相符.通过对比分析发现,有81%的年份两种方法计算的结果一致,且在低温年玉米抽雄期的冷害发生概率均较大,说明东北玉米低温冷害监测预测系统在黑龙江省的应用效果较好,可为防灾减灾提供科学参考.  相似文献   
67.
The phenomenon of the formation of two damaged xylem layers in one frost ring is described in Siberian spruce grown in western Siberian forest-tundra. Temperature conditions providing for the formation of pathological cell and tissue structures are determined. The relationship between the formation of double frost injuries and cold periods is demonstrated.  相似文献   
68.
东北玉米低温冷害时空分布与多时间尺度变化规律分析   总被引:1,自引:0,他引:1  
利用东北地区48个农业气象观测站1961-2010年逐日温度资料和近20多年玉米生育期资料,基于热量指数构建生育阶段冷害指数,采用EOF分析、Mann-Kendall法、子波变换等方法系统分析了近50年东北玉米4个生育阶段低温冷害时空分布及周期特征。结果表明:整个生育期全区平均冷害强度呈极显著的减弱趋势,地区间冷害变化趋势呈现差异化特征,冷害强度减弱趋势由西南向东北方向呈阶梯状递增;4个生育阶段冷害指数EOF第一模态均呈冷害空间变化趋势一致的特征;冷害强度呈较明显的减弱趋势,第1到第4生育阶段减弱趋势逐渐增大,突变均发生在1990年代中期;冷害强度具有较强的周期性,出苗—七叶、出苗—抽雄存在明显的23、25年周期,出苗—乳熟、出苗—成熟均具有较明显的3年周期振荡。  相似文献   
69.
日光温室黄瓜低温冷害风险评估技术研究   总被引:1,自引:0,他引:1  
基于人工气候箱和大田试验观测结果,探讨了日光温室黄瓜生产低温冷害气象指标确定技术,将冬季黄瓜生产低温冷害分为无灾、轻灾、中灾和重灾4个等级,利用层次分析法和GIS技术,对日光温室黄瓜生产低温冷害综合风险进行评估.结果表明,山东省各级冷害出现日数随着低温冷害程度的加重呈减少的趋势,但区域间存在一定差异.鲁北、鲁西北北部、鲁中北部以及半岛内陆地区遭受低温冷害风险较高,半岛东部沿海、鲁西南、鲁南及鲁东南沿海区域风险较低,其他地区属于中度风险.  相似文献   
70.
东北地区玉米低温冷害规律研究   总被引:5,自引:0,他引:5  
以东北地区10 km×10 km的气象要素插值资料以及作物发育期资料为基础,通过计算每个网格点上热量指数和热量指数临界值,得到每个网格点上低温冷害指标值。在此基础上对低温冷害指标进行经验正交分解和小波分析,得到其时空变化规律及多时间尺度特征。玉米冷害3个空间分布型时间系数的分析表明,东北地区玉米低温冷害存在如下规律:第1模态在1971-1992年,呈现准8 a的周期变化规律,第2模态没有呈现很好的周期性规律,第3模态在1963-1974年,呈现准2a的周期变化规律。热量指数变异系数低值区主要分布在平原地区,中值区和高值区主要分布在大兴安岭、小兴安岭、长白山地区以及吉林省白城市沙地,山地和沙地的变异系数要高于平原地区。  相似文献   
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