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71.
废旧电池中的重金属对人体的危害   总被引:7,自引:0,他引:7  
讨论了废旧电池对环境的致毒作用和对人体健康的危害,介绍了废旧电池中重金属在生物体中的吸收、转化、分布、作用部位及毒性,指出人类社会的可持续性发展与自然生态循环的协调一致要求从源头上制止污染,而不是在术端治理污染,即从根本上改变人类的物质生活方式,重新回到生态系统的框架之内。  相似文献   
72.
微量元素锡与健康   总被引:8,自引:0,他引:8  
随着经济的发展,锡及其化合物越来越多地用于现代生活。综述了锡对人体健康的影响,包括:锡的性质、存在,环境污染、抗癌作用以及毒性等方面。  相似文献   
73.
The current study assessed the spatiotemporal variations and human health surveillance associated with organochlorine pesticide (OCP) contamination in water, sediments, and fish from Chenab River, Pakistan. The OCP determinations were performed using high-performance liquid chromatography with a reverse-phase C18 column. The total OCP levels ranged from 13.33 to 274.59?ng/L in water, 4.63 to 239.11?ng/g in sediments, and 23.79 to 387.12?ng/g in fish species. The overall pattern of mean OCP concentrations followed the order as ΣDDTs?>?Σendosulfan?>?aldrin and OCP pollution pattern among the headworks were Khanki Barrage?>?Qadirabad Barrage?>?Trimmu Barrage?>?Marala Barrage in all three environmental matrixes during both seasons. The estimated daily intake (EDI) for ∑OCPs was found to be 22.44?ng/kg/day. The hazard ratios calculated to assess the carcinogenic risk indicated that the values for ∑DDT and aldrin at the 95th percentile concentrations were greater than one, indicating the probability of carcinogenic risk occurrence of one in million populations due to fish consumption. Therefore, these high levels of OCPs and carcinogenic risk through fish consumption highlight the needs of immediate elimination of OCPs from riverine environment of Chenab River and we recommend long-term monitoring-based freshwater ecological studies to be conducted in the study area.  相似文献   
74.
碘、氟、硅与人体健康的关系   总被引:2,自引:1,他引:1  
碘、氟、硅是人体必需微量元素,它们的摄入量对人体健康起着重要作用。对碘、氟、硅的缺乏与疾病之间的关系进行了讨论,并对其治疗和防治方法作了介绍。  相似文献   
75.
Green chemistry can strongly attract students to chemistry. We, therefore, developed a green chemistry educational game that motivates students at the undergraduate and advanced high school levels to consider green chemistry and sustainability concerns as they design a hypothetical, chemical product. The game is intended for incorporation into any chemistry course for majors and non-majors that teaches sustainability and/or the Principles of Green Chemistry at the undergraduate level. The game is free of charge and encourages students to think like professional chemical designers and to develop a chemical product with respect to function and improved human and environmental health. This computer simulation has been assessed by educators and can be seamlessly integrated into an existing curriculum.  相似文献   
76.
针对模拟电路故障预测的特点,提出一种基于PSO优化LS-SVM惩罚因子和核参数的模拟电路故障预测方法。利用小波包分解重构构造能量特征向量,通过计算PPMCC和欧氏距离来表征电路中元件的健康程度,定义为健康度,由此推导出电路发生故障时该元件的故障阈值。应用PSO优化的LS-SVM模型来实现模拟电路的故障预测,预测各个时间点的健康度变化轨迹并估计模拟电路的剩余寿命。通过仿真实验得知,该方法简单便捷,能够有效实现模拟电路的故障预测,具有较好的实用性。  相似文献   
77.
In this paper, a study of in-house built optical coherence tomography (OCT) system with a wavelength of 840 nm for imaging of dental caries, progress in demineralisation and cavity restoration is presented. The caries when imaged with the 840 nm OCT system showed minute demineralisation in the order of 5 μm. The OCT system was also proposed to study the growth of lesion and this was demonstrated by artificially inducing caries with a demineralisation solution of pH 4.8. The progress of carious lesion to a depth of about 50–60 μm after 60 hours of demineralisation was clearly observed with the 840 nm OCT system. The tooth samples were subjected to accelerated demineralisation condition at pH of approximately 2.3 to study the adverse effects and the onset of cavity formation was clearly observed. The restoration of cavity was also studied by employing different restorative materials (filled and unfilled). In the case of restoration without filler material (unfilled), the restoration boundaries were clearly observed. Overall, results were comparable with that of the widely used 1310 nm OCT system. In the case of restoration with filler material, the 1310 nm OCT imaging displayed better imaging capacity due to lower scattering than 840 nm imaging.  相似文献   
78.
目的对脑卒中恢复期患者行中医养生理论护理,观察康复效果。方法择取佛山市禅城区中心医院于2015年1月—2016年5月期间收治的脑卒中恢复期患者102例,参考随机双盲法,将患者划分为研究组与对照组,每组各51例。对照组患者接受常规护理干预,研究组患者接受常规护理干预+中医养生理论护理,比较两组患者的康复效果。结果研究组患者的NIHSS评分、FIM评分以及健康状况评分均显著优于对照组,即相应数据比较,组间差异统计学意义具有显著性(P0.05)。结论对脑卒中恢复期患者行中医养生理论护理,可以改善患者的健康状况,促进患者恢复,进而优化患者生存质量,值得临床推广与应用。  相似文献   
79.
Melamine is a toxic triazine which has been recently proven as a threat to human health. It can be ingested by several methods, being the most important the unethical adulteration of protein-rich foodstuff for economic reasons. This review presents several analytical methods, taken from the literature studies, devoted to the determination of melamine in milk, dietetic supplements, drinking and wastewater, swine kidney, plasma, and urine, using micellar liquid chromatography (MLC). We consider that the control of these samples is crucial to prevent and manage melamine intoxication. This technique has been demonstrated as an excellent tool to determine organic compounds in these matrices. We detail the optimization strategy and the obtained results in the different steps of method development, such as sample pretreatment, chromatographic separation, and validation process. The similarities and differences of the procedures have been described and discussed, as well as their advantages. The main ones were the possibility of direct injection and the efficient chromatographic elution, in spite of the complexity of the samples. Besides, it was found that the MLC procedures were fast, easy-to-handle, inexpensive, eco-friendly, safe, and useful for routine analysis. Therefore, they represent an excellent alternative to reliably evaluate the melamine concentration in that kind of samples.  相似文献   
80.
我国医疗费用增长与医疗设备投入的相关性研究   总被引:3,自引:0,他引:3  
近年来我国卫生总费用占GDP的比例增长很快,而在卫生费用结构上则发生政府投入下降和个人支出的上升。本文采集了大量的统计数据,采用统计相关性研究的方法,论证了医疗设备规模的不断扩大是导致医疗费用上升的主要因素之一;医疗设备的快速增长与医院维修费用投入的增长直接相关,而引起医疗设备维修大量投入的主要原因则是故障期内医疗设备的非正常闲置。本文通过对个人卫生费用的上升、医疗设备规模的扩大及其医疗设备维修投入费用增加相关性的分析,说明了在这种关系下,十分有必要研究医院医疗设备维修体系,以在卫生投入和患者权益上达到平衡。  相似文献   
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