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Toxicological effects involved in risk assessment of rare earth lanthanum on roots of Vicia faba ***

Journal of Environmental Sciences 2011年第10期23卷 1721-1728页

作者： chengrun Wang Mei He Wen Shi Jessie Wong Tao cheng Xiaorong Wang Lingling Hu fenfen chen School of Life Science Huainan Normal University Huainan 232001 China State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210046 China Department of Chemical and Biochemical Engineering University of Western Ontario London ON N6A5B9 Canada Department of Biology University of Western Ontario London ON N6A5B9 Canada

Combined chemical analyses and biological measurements were utilized to investigate potential toxicological effects and possible mechanisms involved in risk assessment of rare earth elements （REEs） on Viciafaba L. seedlings, which were hydroponically cultivated and exposed to various concentrations of lanthanum （La） for 15 days. The results showed that La contents in both the solution and roots increased with the increase of extraneous La, contributing to hormetic dose responses of superoxide dismutase （SOD）, catalase （CAT）, guaiacol peroxidase （GPX）, ascorbate peroxidase （APX） and endoprotease （EP） isozymes activities, and HSP 70 production enhanced at low doses but suppressed at higher doses of La. These physiological responses constituted antioxidant and detoxification systems against La-induced oxidative stress. The elevated La levels also contributed to oxidatively modified proteins, which were most responsible for subsequent cell death and growth retardation of the roots. By combination of hormetic and traditional threshold dose levels, the threshold dose range was deduced to be 108-195 μg La/g dry weight in the roots, corresponding to 0.90-3.12 mg/L of soluble La in the culture solution. It suggests that persistent applications of REEs may lead to potential ecological risk in the environment.

关键词： rare earth elements lanthanum heat shock protein 70 oxidatively modified proteins isoenzymes hormesis riskassessment

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唾液酸糖苷化反应研究新进展

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有机化学 2009年第9期29卷 1317-1324页

作者：梁芬芬陈力邢国文北京师范大学化学学院北京100875

唾液酸是一类重要的具有多种生物学功能的糖酸化合物.唾液酸糖苷化反应条件较一般糖苷化反应苛刻,立体选择性通常较差,端基碳的立体构型较难控制.在唾液酸糖苷化反应中能否高效地得到α糖苷键是评价该反应优劣的重要标志之一.唾液酸苷... 详细信息

唾液酸是一类重要的具有多种生物学功能的糖酸化合物.唾液酸糖苷化反应条件较一般糖苷化反应苛刻,立体选择性通常较差,端基碳的立体构型较难控制.在唾液酸糖苷化反应中能否高效地得到α糖苷键是评价该反应优劣的重要标志之一.唾液酸苷化方法的研究一般涉及以下几个方面:C-2上的离去基团的运用,C-1,C-3上辅助基团的参与作用,C-5上氨基保护基团的修饰,以及一些新的糖苷化反应催化剂的发展.近些年来,这些研究领域,尤其是C-5上氨基保护基团的研究,取得了重要进展.将着重对唾液酸糖苷化方法的新进展做一总结和评述.

关键词：唾液酸糖苷化反应噁唑烷酮

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Discussion on Training Mode of Civil Engineering(Outstanding Engineer)

Discussion on Training Mode of Civil Engineering(Outstanding...

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第四届人文科学与社会发展国际学术会议

作者： Lang Wu Chaocheng Duan Liping Zhu Tingyu Mei fenfen chen College of Architecture and Civil Engineering Jiangxi Science and Normal University College of Architecture and Civil Engineering Nanchang Institiute of Technology Labour Union Jiangxi Science and Normal University

Based on the requirements of "thick foundation, wide caliber, strong ability, and high quality" put forward by the Ministry of Education, through the construction of civil engineering majors in Jiangxi University of Science and Technology, the improvement of the undergraduate talents training program for civil engineering majors was discussed in this paper. It summarizes the present situation of personnel training system, the goal, significances and reform measures of outstanding engineers in civil engineering.

关键词： Civil engineering Excellent Engineer Training Talent development programmes Communication for reform

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Long-Term Maintenance of Luteinizing Hormone –Responsive Testosterone Formation by Primary Leydig Cells in Vitro

Long-Term Maintenance of Luteinizing Hormone –Responsive Te...

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中国药理学会第十届全国基础与临床生殖药理学术研讨会暨2017育英生殖药理论坛

作者： Yiyan Wang fenfen chen June Liu Janet Folmer Barry Zirkin Haolin chen Renshan Ge The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University Department of Biochemistry and Molecular Biology Johns Hopkins Bloomberg School of Public Health

The inability of cultured primary Leydig cells to maintain luteinizing hormone(LH)-responsive testosterone formation in vitro for more than 3-5 days has presented a major challenge in testing the effects of trophic regulatory factors or chronic exposure to environmental toxicants on these critically important *** the present study, our major objective was to establish culture conditions sufficient to maintain LH-responsive testosterone formation for up to a month. The formula contains a mixture of DMEM/F12 and M199 culture medium, containing insulin(10 ug/ml), PDGFAA(10 ng/ml), lipoprotein(0.1 mg/ml), horse serum(1%) and a submaximal amount of LH(0.2 ng/ml). Under this culture condition, adult rat Leydig cells can be maintained in vitro for up to 4 weeks, with littledivision, but retained the ability to respond to LH stimulation and to produce testosterone. As a prove-principle purpose, we have used the culture system tested the chronic effect of a common environmental-relavent compound, MEHP, on Leydig cell testosterone production. The results indicated that while MEHP, at the concentration of 1 uM, did not affect Leydig cell steroidogenesis acutely when incubated with the cells for 24 hours, it indeed significantly inhibited T production when the cells were exposed to the compound for two weeks. The results suggest that the new culture condition we have established is useful to screen and test the potential chronic effects of environmental toxins on Leydig cells.

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Perfluorooctane sulfonate impairs rat Leydig cell development during puberty

Perfluorooctane sulfonate impairs rat Leydig cell developmen...

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中国生理学会生殖科学专业委员会—中国动物学会生殖生物学分会第二次联合学术年会暨“生殖科学专业委员会第二次学术交流会”和“生殖生物学分会第十六次学术年会”

作者： Lili Li Xiaoheng Li Xianwu chen Yong chen Jianpeng Liu fenfen chen Fei Ge Leping Ye Qingquan Lian Ren-Shan Ge The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University

Perfluorooctane sulfonate possibly delays male sexual ***,its effects on pubertal Leydig cell development are *** objective of the present study is to investigate the effects of in vivo exposure to perfluorooctane sulfonate disrupts rat Leydig cell *** male Sprague Dawley rats orally received 5 or 10 mg/kg perfluorooctane sulfonate from

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基于近红外漫反射光谱的盐酸左西替利嗪片判别分析

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量子电子学报 2015年第1期32卷 1-7页

作者：陈芬芬高闽光徐亮中国科学院安徽光学精密机械研究所、中国科学院环境光学与技术重点实验室安徽合肥230031

当前市场上的药品种类繁多,因此对不同厂商的同类药品进行识别分析对规范医药市场及保障人民用药安全有重要现实意义.实验采用基于傅里叶变换近红外漫反射光谱的光谱判别分析方法,结合矢量归一化方法和导数方法对光谱进行预处理,对不同... 详细信息

当前市场上的药品种类繁多,因此对不同厂商的同类药品进行识别分析对规范医药市场及保障人民用药安全有重要现实意义.实验采用基于傅里叶变换近红外漫反射光谱的光谱判别分析方法,结合矢量归一化方法和导数方法对光谱进行预处理,对不同品牌的盐酸左西替利嗪片建立定性识别模型,并用验证集样品对模型进行验证。验证结果表明,通过光谱库判别分析法建立识别模型不能正确识别同一厂家的两种样品,但对不同厂家盐酸左西替利嗪片的识别正确率为100%,该方法可以用于不同企业同类药品的快速定性识别和质量控制.

关键词：傅里叶光学近红外光谱盐酸左西替利嗪片判别分析快速鉴别

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75种陆栖性鸟类羽毛扫描电镜观察

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四川动物 2014年第1期33卷 71-77页

作者：吴新然周用武陈粉粉罗旭西南林业大学研究生院昆明650224 南京森林警察学院南京210046 西南林业大学生命科学学院昆明650224 西南林业大学林学院昆明650224

以75种陆栖性鸟类(雀形目50种,非雀形目25种)的鸟羽为研究对象,在扫描电镜(SEM)下观察翼上覆羽和两胁绒羽的显微结构,计数正羽不同部位的羽小枝小钩个数、纤毛对数、腹齿个数、背刺个数,测量绒羽羽小枝的节间长度、节直径、羽小枝直径... 详细信息

以75种陆栖性鸟类(雀形目50种,非雀形目25种)的鸟羽为研究对象,在扫描电镜(SEM)下观察翼上覆羽和两胁绒羽的显微结构,计数正羽不同部位的羽小枝小钩个数、纤毛对数、腹齿个数、背刺个数,测量绒羽羽小枝的节间长度、节直径、羽小枝直径、色素长度,并对绒羽节的形状进行描述和归类。结果表明,在正羽有钩或无钩羽小枝上,腹齿数均恒定,而在有钩羽小枝上小钩个数和纤毛对数之和在48%的研究对象中保持恒定,据此提出这两个特征参数可作为正羽显微结构特征运用于鸟种鉴定。在绒羽显微特征中,节间长度、节直径、羽小枝直径3项参数可区分雀形目和非雀形目种类,可在鉴定中作为正羽显微结构的补充。以上工作是应用鸟羽显微结构进行物种鉴定工作的探索,为今后构建鸟羽特征数据库奠定了一定的基础。

关键词：鸟羽显微结构正羽羽小枝绒羽羽小枝物种鉴定

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