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61.
近年来,蔬菜的农药残留问题日益成为食品安全中备受关注的焦点.尽管国内外学者对此已有一定研究.但针对蔬菜出口产地的农药使用行为及其对农民健康影响方面的实证研究却相当缺乏.本文根据在山东省取得的调研数据,深入研究了蔬菜出口产地的农药使用行为及其对农民健康的危害.结果表明,农民在使用农药的过程中存在着未能严格按照标签对农药进行稀释等一系列不规范的使用行为;而且不规范地使用农药和缺乏相应的保护措施对农民的整体健康造成了不可忽视的负面影响,其中是否采取保护措施对农民的皮肤健康有着显著的影响;喷洒次数对农民的呼吸系统具有显著的负面影响.在此基础上,本文提出了加大力度宣传正确使用农药的方法以及强化对农药使用的监控措施等相关政策建议.  相似文献   
62.
Specific phobias are highly prevalent among college students and can be quite debilitating. However, students often do not present for treatment for phobias and, when they do, often do not receive effective treatment. This article will present a case study of the effective treatment of specific phobia using cognitive-behavioral therapy with an emphasis on in vivo exposure. It will provide a template for how to conduct this efficient and effective therapy and suggest several benefits of incorporating this treatment into the repertoire offered by a college counseling center.  相似文献   
63.
急性低氧暴露对足球运动员甲襞微循环的影响   总被引:1,自引:0,他引:1  
目的观察急性低氧暴露对足球运动员甲襞微循环的影响及探讨可能的机制。方法让8名北京体育大学体育系男子足球专项运动员晚上在低氧房暴露居住10 h。低氧房中氧含量为15.3%(相当于海拨2500 m)。分别于低氧暴露前1天、急性低氧暴露10 h后测试安静时和定量运动负荷后甲襞微循环的变化。结果急性低氧暴露后,(1)安静时形态积分较高,运动后10 min、15 min的形态积分均比安静时明显降低(P<0.05);(2)运动后即刻的流态积分、总积分均显著高于安静时(P<0.05);(3)运动后5 min、10 min及15 min时,血流速逐渐加快,红细胞聚集程度减轻,积分值降低(P<0.05)。结论急性低氧暴露后,甲襞微循环出现明显的代偿性变化。  相似文献   
64.
This study draws on the nationally representative British Birth Cohort Study (BCS70) to examine (1) the association between social background and early socio-emotional and cognitive competences at age 5 and (2) the relative and independent contributions of early socio-emotional and cognitive competences to educational and socio-economic attainment in adulthood. A multi-dimensional (multiple exposure, multiple outcome) approach is adopted in conceptualising social background, childhood competences and adult outcomes by age 42. Indicators of social background include parental education, social class, employment status, family income, as well as home ownership, enabling us to test which aspects of socio-economic risk uniquely influence the development of early competences. Indicators of childhood competences include directly assessed cognitive competences (i.e. verbal and visual motor skills), while measures of socio-emotional competences include hyperactivity, good conduct, emotional health and social skills, reported by the child’s mother at age 5. Adult outcomes include highest qualifications, social class and household income by age 42. The findings suggest that multiple indicators of social background are associated with both socio-emotional and cognitive competences, although the associations with socio-emotional competences are less strong than those with cognitive competences. We find significant long-term predictive effects of early cognitive skills on adult outcomes, but also independent effects of socio-emotional competences, in particular self-regulation, over and above the role of family background. The study supports calls for early interventions aiming to reduce family socio-economic risk exposure and supporting the development of cognitive skills and self-regulation (i.e. reducing hyperactivity and conduct problems).  相似文献   
65.
研究目的:基于声源识别,得出车外噪声分布特性及场点主要噪声源。创新要点:1.研究高速列车噪声源强特性及频谱特性;2.揭示不同速度下不同声源频谱变化规律;3.分析车外声场场点噪声变化规律及主要声源。研究方法:1.利用车外声源识别系统(图2)分析高速列车声源分布规律及频谱特性;2.利用声源的垂向(图10)分布研究不同声源在各频率下垂向分布规律;3.利用场点声源与速度的拟合关系(图16)研究场点主要噪声源。重要结论:1.高速列车车外噪声源主要分布在轮轨区域、受电弓和车间连接区域;2.轮轨区域噪声包括滚动噪声和气动噪声,在各频率均为最显著声源;3.在整个列车高度,轮轨滚动噪声对总噪声贡献率大于气动噪声;4.车外场点噪声主要频率为630-2500Hz,主要来自轮轨滚动噪声。  相似文献   
66.
运动性低血红蛋白引起红细胞运输氧和二氧化碳的能力及物质代谢能力下降,影响运动能力。实验研究了低氧暴露条件下运动性低血红蛋白游泳运动员的红细胞参数和促红细胞生成素(EPO)的变化情况,探讨低氧防治运动性血红蛋白低下的效果。  相似文献   
67.
68.
A novel stereolithgraphy system with conventional UV light as a light source uses the 2D worktable as moving components, whose characteristics determine the accuracy of the prototyping parts. Many factors including mass of the worktable, elasticity and damp coefficients, speed and acceleration affect the non-uniform exposure time of the resin, and eventually influence the cured line shape and the curing accuracy. A light shuttle is used to eliminate the cure errors, greatly improving accuracy of the parts.  相似文献   
69.
《鸳鸯针》是一部针对明末社会腐败现象痛下针砭的拟话本小说,它通过具体的人物和故事,揭露了科场的腐败、官场的腐败、商界的腐败以及下层社会风气的败坏。作者开出的药方首先是在选拨人才方面不必迷信科举,让绿林中人也为国家效力,其次是要求官员正直廉明,宽厚仁恕,以德报怨,感化坏人;再次是提倡诚实守信,反对损人利巳;提倡贞洁,反对纵欲。他对社会的揭露是有力的,但他开出的药方几乎是无用的。  相似文献   
70.
Increasingly recognized as a distinct form of childhood maltreatment, children’s exposure to intimate partner violence (IPV) has been shown to be associated with an array of negative psychosocial outcomes, including elevated risk for additional violence over the life course. Although studies have identified child exposure to IPV as a predictor of IPV perpetration in adulthood, no review has critically evaluated the methodology of this quantitative work. The present study examines the association between childhood exposure to IPV and the perpetration of IPV in adulthood based on a systematic review of the literature from inception to January 4, 2016. Databases searched included Medline, Embase, PsycINFO, CINAHL, Cochrane Database of Systematic Reviews, Sociological Abstracts and ERIC. Database searches were complemented with backward and forward citation chaining. Studies were critically appraised using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Of 5601 articles identified by the search, 19 studies were included for data extraction. Sixteen of these studies found that child exposure to IPV was significantly and positively associated with adult IPV perpetration; three studies reported null findings. The methodological quality of the studies was low. Work thus far has tended to focus on child exposure to physical IPV and the perpetration of physical IPV within heterosexual contexts. In addition, measures of child exposure to IPV vary in their classification of what exposure entails. We critically discuss the strengths and limitations of the existing evidence and the theoretical frameworks informing this work.  相似文献   
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