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Inhibitory effects of cytosine deaminase gene-transfected bone marrow mesenchymal stem cells on glioma cell proliferation
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作者 Fei Song Qi Xing +6 位作者 Kedong Song Jian Liu Guangchun Ji yufang ma Tianqing Liu Minghai Wei Xuehu ma 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第16期1238-1242,共5页
Bone marrow mesenchymal stem cells were isolated from C57BL mice, transfected with the cytosine deaminase (CD) gene using a lentivirus vector and co-cultured with C6 glioma cells to verify anti-tumor effects of bone... Bone marrow mesenchymal stem cells were isolated from C57BL mice, transfected with the cytosine deaminase (CD) gene using a lentivirus vector and co-cultured with C6 glioma cells to verify anti-tumor effects of bone marrow mesenchymal stem cells carrying CD genes. C57MSC-CD/eGFP cells converted 5-fluorocytosine to 5-fluorouracil and exhibited significant inhibition of proliferation and apoptosis in C6 glioma cells. C57MSC-CD/eGFP cells were then implanted into rat models of brain C6 glioma. Rats were also intraperitoneally injected with 5-fluorocytosine after 7 days. MSC-CD/eGFP cells were irregularly distributed at the margin of the glioma, as well as encased and reduced the volume of the glioma. CD-transfected bone marrow mesenchymal stem cells inhibit the in vivo growth and in vitro proliferation of glioma. 展开更多
关键词 magnetic resonance imaging GLIOMA gene therapy cytosine deaminase gene bone marrow mesenchymal stem cells LENTIVIRUS
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Saponins Content in Fibrous Roots of Pseudostellaria heterophylla and Optimization of the SEP Extraction Technology
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作者 Yanda ZHANG Huiqing PAN +3 位作者 yufang ma Xiaotan YUAN Hegui LIN Qi ZHAO 《Medicinal Plant》 CAS 2020年第4期60-63,共4页
[Objectives]To explore the saponins resources in fibrous roots of Pseudostellaria heterophylla and optimize the SEP technology for extracting saponins.[Methods]Saponins contents in fibrous roots and root tubers of P.h... [Objectives]To explore the saponins resources in fibrous roots of Pseudostellaria heterophylla and optimize the SEP technology for extracting saponins.[Methods]Saponins contents in fibrous roots and root tubers of P.heterophylla were compared;with the fibrous roots as host materials,this experiment applied Box-Behnken design to analyze the influence of steam pressure,maintenance pressure time,moisture content of host materials on the content of saponins extracts.[Results]Saponins content was higher in fibrous roots than in tuberous roots of P.heterophylla;the response surface optimization showed that SEP(steam explosion pretreatment)promoted the contents of saponins and extracts in fibrous roots,and the optimal extracting conditions were stream pressure 1.50 Mpa,maintenance pressure time 54 s,and moisture content of host materials 30%.Under this extracting conditions,the verification value of saponins content experiment was 0.441%,36.53%higher than the untreated control group.[Conclusions]This research offered a new method of exploring saponins resources from fibrous roots of P.heterophylla,and provided a reference for developing new medicinal parts of P.heterophylla. 展开更多
关键词 Fibrous root Pseudostellaria heterophylla SAPONIN Extraction technology Response surface optimization
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Pseudostellaria heterophylla:Antioxidant Activity and Its Mechanism of Action
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作者 Huiqing PAN Yanda ZHANG +1 位作者 yufang ma Qi ZHAO 《Medicinal Plant》 CAS 2021年第4期19-23,共5页
The tonic traditional Chinese medicine Pseudostellaria heterophylla both medicinal and nutritional effects.It has been applied to research in the field of modern aquaculture,and its anti-oxidant clinical trials have a... The tonic traditional Chinese medicine Pseudostellaria heterophylla both medicinal and nutritional effects.It has been applied to research in the field of modern aquaculture,and its anti-oxidant clinical trials have also become a hot spot.Through searching domestic and foreign literature databases to sort out related literature,the anti-oxidation property of P.heterophylla was reviewed systematically from the three levels of in vitro chemical method,biological method and animal experiment method.On this basis,the functional mechanism of the anti-oxidant activity of P.heterophylla explored,in order to provide a reference for the follow-up in-depth research on the anti-oxidation of P.heterophylla and the discovery and development of feed and health care value of P.heterophylla the field of modern animal breeding. 展开更多
关键词 Pseudostellaria heterophylla ANTIOXIDANT MECHANISM
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A review of gas-phase chemical mechanisms commonly used in atmospheric chemistry modelling
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作者 Yanhui Liu Jiayin Li +5 位作者 yufang ma Ming Zhou Zhaofeng Tan Limin Zeng Keding Lu Yuanhang Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第1期522-534,共13页
The atmospheric chemical mechanism is an essential component of airshed models used for investigating the chemical behaviors and impacts of species.Since the first tropospheric chemical mechanism was proposed in the 1... The atmospheric chemical mechanism is an essential component of airshed models used for investigating the chemical behaviors and impacts of species.Since the first tropospheric chemical mechanism was proposed in the 1960s,various mechanisms including Master Chemical Mechanism(MCM),Carbon Bond Mechanism(CBM),Statewide Air Pollution Research Center(SAPRC)and Regional Atmospheric Chemistry Mechanism(RACM)have been developed for different research purposes.This work summarizes the development and applications of these mechanisms,introduces their compositions and lumping methods,and compares the ways the mechanisms treat radicals with box model simulations.CBM can reproduce urban pollution events with relatively low cost compared to SAPRC and RACM,whereas the chemical behaviors of radicals and the photochemical production of ozone are described in detail in RACM.The photolysis rates of some oxygenated compounds are low in SAPRC07,which may result in underestimation of radical levels.As an explicit chemical mechanism,MCM describes the chemical processes of primary pollutants and their oxidation products in detail.MCM can be used to investigate certain chemical processes;however,due to its large size,it is rarely used in regional model simulations.A box model case study showed that the chemical behavior of OH and HO_(2)radicals and the production of ozone were well described by all mechanisms.CBM and SAPRC underestimated the radical levels for different chemical treatments,leading to low ozone production values in both cases.MCM and RACM are widely used in box model studies,while CBM and SAPRC are often selected in regional simulations. 展开更多
关键词 Atmospheric chemistry Gas-phase chemical mechanism OZONE Box model
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中国镍资源供应安全评价与对策研究 被引量:17
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作者 马玉芳 沙景华 +4 位作者 闫晶晶 刘全文 范松梅 何更宇 周平 《资源科学》 CSSCI CSCD 北大核心 2019年第7期1317-1328,共12页
镍是中国紧缺的矿产资源。近年来,由于镍在不锈钢、新能源电池中的大量使用,中国镍资源面临严峻的供应形势。为深入研究中国镍资源的供应安全问题,本文从镍资源存量状况、资源供需状况、资源开发状况、国际产销状况、国际市场价格状况5... 镍是中国紧缺的矿产资源。近年来,由于镍在不锈钢、新能源电池中的大量使用,中国镍资源面临严峻的供应形势。为深入研究中国镍资源的供应安全问题,本文从镍资源存量状况、资源供需状况、资源开发状况、国际产销状况、国际市场价格状况5个维度构建中国镍资源供应安全评价指标体系,首先运用熵值法计算2000—2016年中国镍资源各年的供应安全综合得分,然后运用雷达法分析影响2016年中国镍资源供应安全的主要因素。结果显示:2000—2016年中国镍资源供应安全综合得分持续下降,供应风险不断增加;储量下降、消费量增加、地质勘查投入减少、对国外资源依赖较大、主要进口国政策变化较大等因素是影响中国镍资源供应安全的主要因素。根据评价结果,本文提出以下安全对策:加大镍矿勘探投入,提高镍资源开发水平;提高二次回收率,加强不锈钢领域节镍技术研发;开拓国外镍矿资源市场。这些措施将有助于提高中国镍资源的供应安全保障水平。 展开更多
关键词 镍资源 供应安全 熵值法 雷达法 安全对策 中国
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