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Explanation of the mechanism of carcinogenesis and syntheses of anticancer agents with high selectivity

Science china Chemistry 2006年第1期49卷 44-62页

作者： DAI Qianhuan1,2.1. center of Chemistry and Bioengineering of Cancer Research, beijing Polytechnic {2. (Now known as beijing Univer-sity of Technology), beijing 10002., china 2. center of environmental sciences, peking university, beijing 100871, china center of Chemistry and Bioengineering of Cancer Research Beijing Polytechnic University Beijing China center of environmental {2. Peking University Beijing China

In 1979, the mechanism of chemical carcinogenesis, a challenging anddifficult scientific problem pending for a number of years, was explained by Dai Qianhuan. Themechanism named di-region theory predicted that a carcinogen always metabolizes to form a specialbi-functional alky-lating agent. This agent induces cross-linkages between the complementary basepairs in DMA and switches on initial mutageneses in genomes including point and frameshiftmutations. This, in turn, induces further deep mutageneses including the production of variouschimeric chromosomes, deletions and other aberrations found in genomes. In the end this initiatescarcinogenesis of the whole cell through the reverse transcription mechanism after a lengthyincubation period. Recently, this laboratory has verified that physical carcinogenesis, includingthe oncogenesis induced by radiation and asbestos as well as the carcinogenesis induced byendogenous factors such as estrogen or diethyl-stilbestrol switch on carcinogenesis by inducing theformation of cross-linkages between the complementary base pairs in DNA. Di-region theory has nowbeen supported by many experimental observations such as mutational spectra of various *** potential for carcinogenesis, teratogenesis, sterility and mutagenesis lumped together asgenetic toxicity appears to originate almost uniformly from the cross-linking between complementarybases, i.e. malignant cross-linking, which is in accordance with di-region theory. Other forms ofcross-linking between non-complementary bases, benign cross-linkings, show bi-functional alkylationanticancer activity but lack genetic toxicity. The predictable design and synthesis of a highselectivity anticancer agent with high efficacy and low genetic toxicity, a goal long pursued incancer chemotherapy, have been realized for the first time in this laboratory by inhibitingmalignant and heightening benign cross-linking using the principles of di-region theory. A series ofpatented new anticanc

关键词： mechanism of carcinogenesis, di-region theory, minoplatin, selectivity of anticancer agent, cross-linking between DNA bases, anticancer platinum complexes, predictive design of anticancer agent, second generation anticancer agent.

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china's energy, environment and policy perspective

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Journal of environmental sciences 2000年第3期12卷 270-274页

作者： ZHANG Shi\|qiu (center for environmental {2., peking university, beijing 100871, china) center for environmental {2. Peking University Beijing 100871 China

This paper discusses the specific features of the energy in china, and addresses those key challenges in china is that the co\|exist of (1) higher total energy production and lower per capita level; (2. lower per capita energy resources level with unrational energy consumption structure; (3) lower energy utilization efficiency and higher energy conservation potential; and (4) unequal distribution of energy resources. It reviews the key {2. problems related to the feature of energy production and consumption. Based on the analysis, the author furthers addresses the policy and actions needed.

关键词： energy energy production energy consumption environment policy

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Study on urban water environmental support capacity

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Journal of environmental sciences 1995年第4期7卷 430-434页

作者： Guo Huaicheng Ye Wenhu(center of environmental {2. , peking university , beijing 100871 , china) Ctr of Envmtl sciences Peking Univ Beijing China China

ＳｔｕｄｙｏｎｕｒｂａｎｗａｔｅｒｅｎｖｉｒｏｎｍｅｎｔａｌｓｕｐｐｏｒｔｃａｐａｃｉｔｙＧｕｏＨｕａｉｃｈｅｎｇ；ＹｅＷｅｎｈｕ（ＣｅｎｔｅｒｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒ... 详细信息

ＳｔｕｄｙｏｎｕｒｂａｎｗａｔｅｒｅｎｖｉｒｏｎｍｅｎｔａｌｓｕｐｐｏｒｔｃａｐａｃｉｔｙＧｕｏＨｕａｉｃｈｅｎｇ；ＹｅＷｅｎｈｕ（ＣｅｎｔｅｒｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７...

关键词： water environmental support capacity urban water environment development variablesi supportvariables.

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Marginal cost pricing for coal fired electricity in coastal cities of china:The case of Mawan Electricity Plant in Shenzhen City, china

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Journal of environmental sciences 2003年第3期15卷 401-412页

作者： ZHANG Shi-qiu, DUAN Yan-xin (center for environmental {2., peking university, beijing 100871, china.) center for environmental {2. Peking University 北京 100871

By developing a GDMOD model to estimate the environmental externalities associated with electricity generation, this project provides a detailed analysis of the damages and costs caused by different pollutants at varying distances from the Mawan Electricity Plant in Shenzhen, china. The major findings of this study can be summarized that (1) environmental damages caused by electricity production are large and are mainly imposed on regions far away from the electricity plant; (2. air pollution is the most significant contributor to the total damages, and SO_2. NOx, and particulate matter are the three major pollutants with highest damages; (3) the damages caused per unit of particulate, NOx, and SO_2.emissions are much higher than pollution treatment and prevention costs. The research results of this project showed that china needs to have a more effective levy system on SO_2. and a more manageable electricity tariff mechanism to internalize the environmental externalities. The results have also implications for pollution control strategies, compensation schemes as well as emission trading arrangements.

关键词： marginal cost pricing environmental damages environmental policy

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Fluxes of NH_3 and HNO_3 over heathland in the Netherlands:implications for chemical interactions

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Journal of environmental sciences 1997年第1期9卷 49-58页

作者： Zhang Yuanhang center of environmental {2.,peking university,beijing 100871,china center of environmental {2. Peking University Beijing 100871 China

The surface exchange of NH_3 and HNO_3 gases over heathland was measured with the aerodynamic gradient method in Leende,the Netherlands during April 2. and May 9,*** to reactions in the system NH_3,HNO_3 and NH_4NO_3,the NH_3 deposition flux is overestimated,while HNO_3 shows apparent emission fluxes mostly during the field *** reveal that NH_3 gradients are influenced slightly by HNO_3 and the HNO_3 gradients are strongly controlled by the NH_3.A clear relationship between NH_3 and HNO_3 gradient is suggested by the Leende experiment. Before the late afternoon,NH_3 deposition gradients will cause HNO_3 upward gradients,meanwhile the NH_3 gradients themselves will become *** the HNO_3 upward gradient reaches maxi- mum,the NH_3 deposition gradients will be enlarged or the emission gradients depressed,while the HNO_3 upward gradients become smaller.

关键词： dry deposition ammonia nitric acid equilibrium,fluxes.

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environmental regulatory and policy framework in china: an overview

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Journal of environmental sciences 2001年第1期13卷 122-128页

作者： ZHANG Shi qiu (center for environmental {2., peking university, beijing 100871, china. E mail: zhangshq@***) 北京大学北京 100871

china has developed one of the most comprehensive environmental regulatory and policy framework in the world. This paper provides a description of the main institutions for environmental management in china, and overv... 详细信息

关键词： Laws and legislation Public policy Regulatory compliance Societies and institutions

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Analysis　of　relationship　between　economic　growth　and　environment　in　Benxi　Shiqiaozi　Development　Zone

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Journal of environmental sciences 1996年第3期8卷 269-274页

作者： Li Bin Ru Jiang Ye Wenhu Xu Yunlin(center for environmental {2., peking university, beijing 100871,china) center for environmental {2. Peking University Beijing 100871 China

How to express and assess the coordination between environmental system and economic system is one crucial problem for the studies on regional sustainable *** present study applies environmental supporting capacity (ESC) to evaluate the comparative coordination of economic development plans in a case study in Shiqiaozi Development *** analysis conclusion showed the method is practicable.A new method for judging the efficiency of utilization of environmental system is also discussed in this paper.

关键词： sustainable development coordination environmental supporting capacity(ESC) Benxi Shiqiaozi Development Zone (BSDZ)

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Determination of atmospheric concentrations of halocarbons in beijing area

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Journal of environmental sciences 1993年第1期5卷 76-82页

作者： Wang ShaobinResearch center for Eco-environmental {2., Chinese Academy of {2., beijing 100085, chinaPeng Lixin and Tang XiaoyanResearch center of environmental {2., peking university, beijing 100871, china Research center for Eco-environmental {2. Chinese Academy of Sciences Beijing 100085 China. China

Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over beijing. Halogenated compounds such as CFC-11, CFC-12. CHCl_3, CCl_4, CH_3CCl_3, CHCl =CCl_2. and CCl2.CCl2.were measured and their concentrations are 109±8, 2.4±13, 47±2., 97±2., 88±2., 11±1 and 17±3 (pptv), respectively.

关键词： GC-ECD atmospheric halocarbons beijing.

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Excessive Cu and Zn affecting on distribution of the metals and activities of glycolytic and nitrogen incorporating key enzymes in mycelia of ectomycorrhizal fungi Suillus bovinus

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Journal of environmental sciences 2001年第3期13卷 337-341页

作者： HUANG Yi, TAO Shu(Department of Urban and environmental sciences,{2., beijing 100871, china. 北京大学北京 100871

Concentration of copper and zinc in isolated Suillus bovinus mycelia, used nutrient solution and 0.5 mol/L EDTA mycelia washing solution were measured to investigate the distribution of heavy metals in mycelia growth in excess copper or zinc nutrient solution. Treated with zinc, most of added zinc maintained in used solution, and 9.8%/14.6% was in/on mycelia in treatment, and in treatment 2.was 3.9%/8.0% in/on mycelia. In the copper applications, copper stimulated in more than on mycelia, i.e., 2..9%/4.5% in/on mycelia in treatment, and 7%/18.8% in/on mycelia while most of copper retained in used nutrient solution. Certain amount of copper or zinc uptake by mycelia led to pronounced influence on glycolysis and nitrogen incorporating process of Suillus bovinus, while the tested enzymes kept constant in treatment. In crude extracts of copper treatment 2.mycelia, activities of HK, PFK and GS were inhibited and decrease to 63%, 48% and 38% and GIDH increased by 68% of the control, respectively. The behaviors of these tested enzymes toward zinc corresponded in general with that towards copper. The potential protection of Suillus bovinus for its host plant under excess copper or zinc threaten was discussed.

关键词： Suillus bovinus ectomycorrhizal fungous copper zinc glycolysis nitrogen incorporate enzymes

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Soluble protein and acid phosphatase exuded by ectomycorrhizal fungi and seedlings in response to excessive Cu and Cd

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Journal of environmental sciences 2009年第12期21卷 1667-1672页

作者： ZHENG Weishuang, FEI Yingheng, HUANG Yi College of environmental sciences and Engineering,{2., beijing 100871, china. College of environmental sciences and Engineering Peking University Beijing 100871 China

Fungi and their symbionts can alleviate heavy metal stress by exuding soluble proteins and enzymes. This study examined the role of soluble protein and acid phosphatase （APase） exuded by Xerocomus chrysenteron, an ectomycorrhizal fungus, and the seedlings of its symbiont, Chinese pine （Pinus tabulaeformis）, under conditions of excessive Cu and Cd. The growth type showed that this poorly studied ectomycorrhizal fungus was capable of tolerating high concentrations of Cu, and may be useful in phytoremediation. X. chrysenteron grew well at 80 mg/L Cu, and the EC50 for Cd was 17.82.mg/L. X. chrysenteron also showed enhanced exudation of soluble protein in both isolated and inoculated cultivations under the influence of Cu and Cd. Soluble protein exudation, however, differed under Cu and Cd stress in isolates. In mediums containing Cu, soluble protein exudation increased with concentration, but in mediums containing Cd the content of soluble protein increased to a comparable level at all concentrations. This study demonstrated that soluble protein was related to heavy metal tolerance, although the different ions played different roles. While APase activity in exudates of fungi and seedlings decreased under Cu and Cd stress in comparison to the control, the APase activity in seedlings was maintained by inoculation. Thus, X. chrysenteron facilitated the ability of plant to maintain a normal nutrient uptake, and therefore to protect it from heavy metal toxicity.

关键词： soluble protein acid phosphatase exudate Cu, Cd Xerocomus chrysenteron

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