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481.
Nilima N. Dongre Adinath N. Suryakar Arun J. Patil Jeevan G. Ambekar Dileep B. Rathi 《Indian journal of clinical biochemistry : IJCB》2011,26(4):400-406
The purpose of this study was to find out the effect of lead exposure on systolic and diastolic blood pressure, heme biosynthesis
related and hematological parameters of automobile workers. For this study 30 automobile workers were selected and compared
with 30 age matched healthy control subjects. Significantly increased blood lead (364%, P < 0.001) and urinary lead (176%, P < 0.001) levels were observed in automobile workers (study group) as compared to controls. Systolic blood pressure (5.32%,
P < 0.05) and diastolic blood pressure (5.87%, P < 0.05) were significantly increased in the automobile workers as compared to controls. The significantly decreased non-activated
erythrocyte δ-aminolevulinic acid dehydratase (δ-ALAD) (−18.51%, P < 0.01) and activated δ-ALAD (−13.29%, P < 0.05) levels were observed in automobile workers as compared to normal healthy control subjects. But the ratio of activated/non-activated
δ-ALAD was significantly increased (43.83%, P < 0.001) in automobile workers as compared to controls. Excretions of δ-aminolevulinic acid (83.78%, P < 0.001) and porphobilinogen (37%, P < 0.001) in urine were significantly increased in the study group as compared to the controls. In automobile workers heamoglobin
(−11.51%, P < 0.001), hematocrit (−4.06%, P < 0.05), mean corpuscle volume (−3.34%, P < 0.05), mean corpuscle hemoglobin (−5.66%, P < 0.01), mean corpuscle hemoglobin concentration (−7.67%, P < 0.001), red blood cell count (−14.6%, P < 0.001) were significantly decreased and total white blood cell count (11.44%, P < 0.05) increased as compared to the controls. The results of this study clearly indicate that the absorption of lead is
more in automobile workers and it affects on blood pressure, heme biosynthesis and hematological parameters observed in this
study group. 相似文献
482.
To address the growing energy demands of sustainable development, it is crucial to develop new materials that can improve the efficiency of energy storage systems. Hierarchically structured porous materials have shown their great potential for energy storage applications owing to their large accessible space, high surface area, low density, excellent accommodation capability with volume and thermal variation, variable chemical compositions and well controlled and interconnected hierarchical porosity at different length scales. Porous hierarchy benefits electron and ion transport, and mass diffusion and exchange. The electrochemical behavior of hierarchically structured porous materials varies with different pore parameters. Understanding their relationship can lead to the defined and accurate design of highly efficient hierarchically structured porous materials to enhance further their energy storage performance. In this review, we take the characteristic parameters of the hierarchical pores as the survey object to summarize the recent progress on hierarchically structured porous materials for energy storage. This is the first of this kind exclusively to survey the performance of hierarchically structured porous materials from different porous characteristics. For those who are not familiar with hierarchically structured porous materials, a series of very significant synthesis strategies of hierarchically structured porous materials are firstly and briefly reviewed. This will be beneficial for those who want to quickly obtain useful reference information about the synthesis strategies of new hierarchically structured porous materials to improve their performance in energy storage. The effect of different organizational, structural and geometric parameters of porous hierarchy on their electrochemical behavior is then deeply discussed. We outline the existing problems and development challenges of hierarchically structured porous materials that need to be addressed in renewable energy applications. We hope that this review can stimulate strong intuition into the design and application of new hierarchically structured porous materials in energy storage and other fields. 相似文献
483.
传统的网络入侵检测算法,使用的都是同一个或者相似的特征基作为入侵检测的衡量标准,但是在多层网络中,不同层次的特征基参数存在差异,检测结果误差较大。为此提出了一种基于多层特征基参数融合的网络入侵检测算法。通过提取多层网络操作差异特征基参数,利用非线性回归方式对每层特征基参数进行差异补偿,按照自适应融合方式对多层差异特征基进行融合处理,以此作为检测的基础。实验表明,该算法提高了检测的准确率,取得了理想的效果。 相似文献
484.
485.
毕志远 《河北体育学院学报》2021,35(1):77-82
目的:探讨男子百米一二级运动员起跑加速技术差异及影响短跑起跑加速效果的主要因素。方法:采用三维高速红外摄像解析法对男子百米一级运动员(6名)和二级运动员(7名)的起跑和前3步加速技术动作进行分析。结果:①起跑器上阶段一二级运动员摆动腿屈髋角速度峰值具有显著性差异(P<0.05),摆动腿屈髋角速度峰值与平均水平速度呈正相关(P<0.05),与支撑时间呈负相关(P<0.05);②第1步水平速度与支撑时间、支撑距离呈正相关(P<0.05),第2步水平速度与支撑时间、支撑距离呈正相关(P<0.05),与腾空时间呈负相关(P<0.05);③起跑和前3步加速一二级运动员平均步频与平均水平速度之间呈正相关(P<0.05)。结论:起跑和前3步加速不同阶段的技术特点是不同的,起跑器上阶段是为了获得较大起动速度,因此要求较大的摆动腿屈髋角速度峰值、更短的支撑时间,而第1步和第2步加速阶段提高水平速度则需要更长的支撑时间、支撑距离和更短的腾空时间,起跑和前3步加速较快的步频有利于水平速度的提高。 相似文献