大气PM_(2.5)中重金属研究进展

近年来大气PM_(2.5)污染及其危害受到全球关注,我国污染现状尤其严重。作为重要的大气污染物成分,PM_(2.5)富集的重金属对生态环境和人体健康有较大威胁。该文分析总结了我国大气PM_(2.5)中重金属的研究现状,包括污染水平、时空分布特征、来源解析、化学形态、生物有效性和毒理健康效应等方面,提出了现阶段研究的不足,并对今后大气颗粒物污染及其成分研究进行展望,以利于环境空气质量的合理评价及其标准完善,为大气污染防治决策提供科学依据。     

3D-Resolved Investigation of the pH Gradient in Artificial Skin Constructs by Means of Fluorescence Lifetime Imaging

Purpose The development of substitutes for the human skin, e.g., artificial skin constructs (ASCs), is of particular importance for pharmaceutical and dermatologic research because they represent economical test samples for the validation of new drugs. In this regard, it is essential for the skin substitutes to be reliable models of the genuine skin, i.e., to have similar morphology and functionality. Particularly important is the barrier function, i.e., the selective permeability of the skin, which is strongly related to the epidermal pH gradient. Because the pH significantly influences the permeation profile of ionizable drugs such as nonsteroidal anti-inflammatory drugs, it is of major importance to quantitatively measure the epidermal pH gradient of the ASC and compare it to that of genuine skin.Methods Using three-dimensional fluorescence lifetime imaging combined with two-photon scanning microscopy, we measured with submicron resolution the three-dimensional pH gradient in the epidermis of ASCs stained with 2′,7′-bis-(2-carboxyethyl)-5/6-carboxyfluorescein.Results Similar to genuine skin, the surface of the artificial epidermis has an acidic character (pH 5.9), whereas in the deeper layers the pH increases up to 7.0. Moreover, the pH gradient differs in the cell interior (maximally 7.2) and in the intercellular matrix (maximally 6.6). Apart from the similitude of the pH distribution, the genuine and the artificial skin prove to have similar morphologies and to be characterized by similar distributions of the refractive index.Conclusions Artificial skin is a reliable model of genuine human skin, e.g., in permeability studies, because it is characterized by a similar pH gradient, a similar morphology, and a similar distribution of the refractive index to that of genuine skin.     

The welfare value of FDA's mercury-in-fish advisory: A dynamic reanalysis

Assessing the welfare impact of consumer health advisories is a thorny task. Recently, Shimshack and Ward (2010) studied how U.S. households responded to FDA's 2001 mercury-in-fish advisory. They found that the average at-risk household reduced fish consumption by 21%, resulting in a 17%-reduction in mercury exposure at the cost of a 21%-reduction in cardioprotective omega-3 fatty acids. Based on a static assessment of the health costs and benefits Shimshack and Ward concluded that the advisory policy resulted in an overall consumer welfare loss. In this note, we propose a dynamic assessment that links the long-term cardiovascular health effects of the advisory to life-cycle consumption. We find that under reasonable assumptions the welfare loss might be much larger than suggested. Our analysis highlights the importance of accounting for dynamic effects when evaluating persistent changes in exposure to environmental health risks.     

AERMOD在核设施辐射环境影响评价中的应用研究

目的 基于AERMOD模型机理,研究其在核设施辐射环境影响评价中的应用。方法 根据给定的释放源项和厂址气象数据,模拟获取核设施常规运行时气态放射性核素浓度分布,并进一步定性分析气态流出物浓度峰值落地点和时间分布,研究AERMOD模型在核设施辐射环境影响评价中的适用性和应用前景。结果 通过AERMOD模型适用性和应用前景分析,得出该模型总体满足核设施气态流出物浓度分布计算需求,可应用于核设施气态流出物扩散趋势和敏感点分析,并可为核设施常规运行的监测计划提供数据支撑。结论 本研究可为今后深入开展AERMOD模型在核设施辐射环境影响评价中的应用提供参考。     

淫羊藿、巴戟复方提取液的实验研究

目的 研究由淫羊藿、巴戟两种药物组方制成的复方提取液的抗疲劳、抗衰老作用及雄性激素作用.方法 应用淫羊藿、巴戟两药制备了淫羊藿、巴戟复方提取液;并进行了淫羊藿、巴戟复方提取液淫羊藿甙的含量测定和不同乙醇浓度提取淫羊藿中的淫羊藿甙含量的比较;对淫羊藿、巴戟复方提取液的增强体力、抗疲劳、抗衰老、雄性激素样作用进行了动物药理研究.结果 淫羊藿、巴戟复方提取液有提高小白鼠常压耐缺氧的能力,能延长负重游泳的存活时间,未见有明显提高交配能力的作用,未见明显毒性作用.结论 淫羊藿、巴戟复方提取液具有增强体力和抗疲劳作用,且毒性低.     

核辐射突发事件气载放射性物质大气弥散计算软件的研发

目的：研发气载放射性物质大气弥散计算软件,为在核辐射突发事件发生后能够快速、准确地计算出气载放射性物质的扩散范围。方法：以高斯模式为计算基础,在考虑重力沉降、地面反射和放射性衰变等因素的条件下,进行大气弥散计算。结果：设计并研发出核辐射突发事件气载放射性物质大气弥散计算软件,以表格、制图和下风向坐标点设置等形式给出计算结果。结论：该软件可有效降低气载放射性物质扩散计算的难度,满足核辐射突发事件应急响应的需要。     

7月气温和降雨量对湖北省四湖地区急性血吸虫病检出率的影响及预报初探

「目的」探索用气温和降雨量预报急性血吸虫病检出率的新途径。「方法」收集我国湖北省四湖地区１９７６～１９８９年急性血吸虫人出率（急血率）和相应地区７月气温和降雨量资料,并用ＳＰＳＳ８．０软件做多元回归分析。「结果」该区１９７６～１９８９年年急血率（ｙ）与７月份平均气温（ｘ２）呈负相关（ｒ＝－０．７４９５,Ｐ〈０．０５）,与７月份平均降雨量（ｘ１）呈正相关（ｒ＝０．７３５７,Ｐ〈０．０５）。所获预报模     

输尿管镜气压弹道碎石治疗输尿管结石(附108例报告)

目的探讨输尿管镜气压道弹碎石术治疗输尿管结石的临床疗效.方法在输尿管镜窥视下采用气压弹道碎石机对108例输尿管结石进行治疗.结果 103例原位碎石成功,总成功率95.3%,其中输尿管上段结石成功率为83.3%,中段结石为96.3%,下段结石为98.4%.平均碎石时间(4.5±2.2)min,术后1～3个月结石排净率100%.结论输尿管镜气压弹道碎石术治疗输尿管结石具有安全、有效、容易操作等特点,是治疗输尿管结石的首选方法.     

Analyse de la qualité des données issues des hôpitaux de Beyrouth Municipe pour mesurer les effets à court terme de la pollution atmosphérique

BackgroundThe effects of air pollution on human health have been the subject of much public health research. Several techniques and methods of analysis have been developed. Thus, Beirut Air Pollution and Health Effects (BAPHE) was designed to develop a methodology adapted to the context of the city of Beirut in order to quantify the short-term health effects of air pollution.MethodsThe quality of data collected from emergency units was analyzed in order to properly estimate hospitalizations via these units. This study examined the process of selecting and validating health and pollution indicators.ResultsThe different sources of data from emergency units were not correlated. BAPHE was therefore reoriented towards collecting health data from the emergency registry of each hospital. A pilot study determined the appropriate health indicators for BAPHE and created a classification methodology for data collection.ConclusionIn Lebanon, several studies have attempted to indirectly assess the impact of air pollution on health. They had limitations and weaknesses and offered no recommendations regarding the sources and quality of data. The present analysis will be useful for BAPHE and for planning further studies.     

大气可吸入颗粒物和四种重金属致突变性研究

本研究以体外微核、姐妹染色单体互换(SCE)、DNA单链断裂及体内微核为指标对Ni、Pb、Cr、Cd和太原市大气中可吸入颗粒物提取液进行了遗传毒性检验,结果表明四种金属元素及可吸入颗粒物提取液均可产生一定的遗传毒性。