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农村减贫:应该更关注教育还是健康?——基于收入增长和差距缩小双重视角的实证 被引量:315
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作者 程名望 Jin Yanhong +1 位作者 盖庆恩 史清华 《经济研究》 CSSCI 北大核心 2014年第11期130-144,共15页
基于2003-2010年全国农村固定观察点微观住户数据,运用分位数回归方法,从收入增长与差距缩小的双重视角研究了健康与教育对中国农户贫困的影响。研究发现:2003-2010年间,中国农村贫困发生率呈现逐年降低的趋势,这一趋势主要得益于农户... 基于2003-2010年全国农村固定观察点微观住户数据,运用分位数回归方法,从收入增长与差距缩小的双重视角研究了健康与教育对中国农户贫困的影响。研究发现:2003-2010年间,中国农村贫困发生率呈现逐年降低的趋势,这一趋势主要得益于农户收入增长,而不是收入差距缩小。健康与教育所体现的人力资本是影响农户收入水平的显著因素,对农村减贫具有显著作用。但从收入差距缩小视角看,健康对农村减贫的作用比教育更为显著。坚持提升农村人力资本积累的基本战略取向,特别是提高贫困农户健康水平,对于农村减贫具有较强的政策意义。 展开更多
关键词 健康 教育 贫困 分位数回归
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农户收入水平、结构及其影响因素——基于全国农村固定观察点微观数据的实证分析 被引量:98
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作者 程名望 史清华 Jin Yanhong 《数量经济技术经济研究》 CSSCI 北大核心 2014年第5期3-19,共17页
本文采用2003~2010年全国农村固定观察点微观住户调查数据,研究了我国农户收入水平、结构及其影响因素。研究发现,农户收入水平及增速均滞后于城镇居民,其主要收入来源是劳动性收入,而资产性收入的比例较低。农户收入水平的影响因... 本文采用2003~2010年全国农村固定观察点微观住户调查数据,研究了我国农户收入水平、结构及其影响因素。研究发现,农户收入水平及增速均滞后于城镇居民,其主要收入来源是劳动性收入,而资产性收入的比例较低。农户收入水平的影响因素既有产业差异、区域分割、制度与政策等宏观因素,也有农户人力资本积累、物质资本投入、金融资产与社会资本拥有、农户家庭特征等微观因素。金融资产和区域经济发展水平等因素对农户收入的影响是全面性的;人力资本、物质资本、金融资产、社会资本及制度与政策等因素对农户收入的影响是结构性的。 展开更多
关键词 农户 收入水平 收入结构 全国农村固定观察点
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Discovery of direct inhibitors of Keap1–Nrf2 protein–protein interaction as potential therapeutic and preventive agents 被引量:52
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作者 Dhulfiqar Ali Abed Melanie Goldstein +2 位作者 Haifa Albanyan Huijuan Jin Longqin Hu 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2015年第4期285-299,共15页
The Keap1–Nrf2–ARE pathway is an important antioxidant defense mechanism that protects cells from oxidative stress and the Keap1–Nrf2 protein–protein interaction(PPI) has become an important drug target to upregul... The Keap1–Nrf2–ARE pathway is an important antioxidant defense mechanism that protects cells from oxidative stress and the Keap1–Nrf2 protein–protein interaction(PPI) has become an important drug target to upregulate the expression of ARE-controlled cytoprotective oxidative stress response enzymes in the development of therapeutic and preventive agents for a number of diseases and conditions. However, most known Nrf2 activators/ARE inducers are indirect inhibitors of Keap1–Nrf2PPI and they are electrophilic species that act by modifying the sulfhydryl groups of Keap1's cysteine residues. The electrophilicity of these indirect inhibitors may cause "off-target" side effects by reacting with cysteine residues of other important cellular proteins. Efforts have recently been focused on the development of direct inhibitors of Keap1–Nrf2 PPI. This article reviews these recent research efforts including the development of high throughput screening assays, the discovery of peptide and small molecule direct inhibitors, and the biophysical characterization of the binding of these inhibitors to the target Keap1 Kelch domain protein. These non-covalent direct inhibitors of Keap1–Nrf2 PPI could potentially be developed into effective therapeutic or preventive agents for a variety of diseases and conditions. 展开更多
关键词 Oxidative stress KEAP1 NRF2 Direct inhibitors of protein–protein interaction High throughput screening assays Structure–activity relationships X-ray crystallography
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Applications of electronic nose (e-nose) and electronic tongue (e-tongue) in food quality-related properties determination: A review 被引量:43
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作者 Juzhong Tan Jie Xu 《Artificial Intelligence in Agriculture》 2020年第1期104-115,共12页
Background:An e-nose or an e-tongue is a group of gas sensors or chemical sensors that simulate human nose or human tongue.Both e-nose and e-tongue have showngreat promise and utility in improving assessments of food ... Background:An e-nose or an e-tongue is a group of gas sensors or chemical sensors that simulate human nose or human tongue.Both e-nose and e-tongue have showngreat promise and utility in improving assessments of food quality characteristics compared with traditional detection methods.Scope and approach:This review summarizes the application of e-nose and e-tongue in determining the quality-related properties of foods.The working principles,applications,and limitations of the sensors employed by electronic noses and electronic tongueswere introduced and compared.Widelyemployed pattern recognition algorithms,including artificial neural network(ANN),convolutional neural network(CNN),principal component analysis(PCA),partial least square regression(PLS),and support vector machine(SVM),were introduced and compared in this review.Key findings and conclusions:Overall,e-nose or e-tongue combining pattern recognition algorithms are very powerful analytical tools,which are relatively low-cost,rapid,and accurate.E-nose and e-tongue are also suitable for both in-line and off-line measurements,which are very useful in monitoring food processing and detecting the end product quality.The user of e-nose and e-tongue need to strictly control sample preparation,sampling,and data processing. 展开更多
关键词 E-NOSE E-tongue Food quality assessments
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退化湿地生态系统的生态恢复与管理——以美国Hackensack湿地保护区为例 被引量:29
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作者 陈芳清 Jean Marie Hartman 《自然资源学报》 CSSCI CSCD 北大核心 2004年第2期217-223,共7页
受城市化、工业化和地球温室效应等人类活动与自然因素的影响,美国Hackensack湿地保护区正面临着面积不断减少、景观破碎化、外来物种入侵、河水污染增加、盐碱化程度增加和范围扩大等生态胁迫。稳定湿地面积,重建湿地的复合景观,丰富... 受城市化、工业化和地球温室效应等人类活动与自然因素的影响,美国Hackensack湿地保护区正面临着面积不断减少、景观破碎化、外来物种入侵、河水污染增加、盐碱化程度增加和范围扩大等生态胁迫。稳定湿地面积,重建湿地的复合景观,丰富生物多样性,恢复潮水的正常规律,减少水体污染,控制外来种的入侵与扩张,促进湿地原有植物的定居与扩增及原有植被的恢复是Hackensack湿地恢复的关键,也是恢复工程设计与实施的核心。退化湿地生态恢复的管理则以植被的生长、芦苇的扩散方式及动态、鱼类和蟹类的种群动态、鸟类的种类及其对生境地的利用情况对生态系统功能恢复状况进行生物检验,有效监控退化湿地生态系统的恢复动态,研究其恢复规律,进而采取相应的管理措施,科学调控生态恢复进程。 展开更多
关键词 退化生态系统 湿地 生态恢复 生态管理 生物检验
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Gain-of-function mutant p53 in cancer progression and therapy 被引量:35
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作者 Cen Zhang Juan Liu +3 位作者 Dandan Xu Tianliang Zhang Wenwei Hu Zhaohui Feng 《Journal of Molecular Cell Biology》 SCIE CAS CSCD 2020年第9期674-687,共14页
p53 is a key tumor suppressor,and loss of p53 function is frequently a prerequisite for cancer development.The p53 gene is the most frequently mutated gene in human cancers;p53 mutations occur in>50%of all human ca... p53 is a key tumor suppressor,and loss of p53 function is frequently a prerequisite for cancer development.The p53 gene is the most frequently mutated gene in human cancers;p53 mutations occur in>50%of all human cancers and in almost every type of human cancers.Most of p53 mutations in cancers are missense mutations,which produce the full-length mutant p53(mutp53)protein with only one amino acid difference from wild-type p53 protein.In addition to loss of the tumor-suppressive function of wild-type p53,many mutp53 proteins acquire new oncogenic activities independently of wild-type p53 to promote cancer progression,termed gain-of-function(GOF).Mutp53 protein often accumulates to very high levels in cancer cells,which is critical for its GOF.Given the high mutation frequency of the p53 gene and the GOF activities of mutp53 in cancer,therapies targeting mutp53 have attracted great interest.Further understanding the mechanisms underlying mutp53 protein accumulation and GOF will help develop effective therapies treating human cancers containing mutp53.In this review,we summarize the recent advances in the studies on mutp53 regulation and GOF as well as therapies targeting mutp53 in human cancers. 展开更多
关键词 tumor suppressor p53 MUTATION GAIN-OF-FUNCTION TUMORIGENESIS cancer therapy
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Early neurosurgical intervention of spinal cord contusion: an analysis of 30 cases 被引量:30
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作者 ZHU Hui FENG Ya-ping +4 位作者 Young Wise YOU Si-wei SHEN Xue-feng LIU Yan-sheng JU Gong 《Chinese Medical Journal》 SCIE CAS CSCD 2008年第24期2473-2478,共6页
Background The incidence of spinal injury with spinal cord contusion is high in developed countries and is now growing in China. Furthermore, spinal cord injury happens mostly in young people who have a long life expe... Background The incidence of spinal injury with spinal cord contusion is high in developed countries and is now growing in China. Furthermore, spinal cord injury happens mostly in young people who have a long life expectance. A large number of patients thus are wheelchair bound for the rest of their lives. Therefore, spinal cord injury has aroused great concern worldwide. Despite great efforts, recovery from spinal cord injury remains unsatisfactory. Based on the pathology of spinal cord contusion, an idea of early neurosurgical intervention has been formulated in this study. Methods A total of 30 patients with "complete" spinal cord injury or classified as American Spinal Injury Association (ASIA)-A were studied. Orthopedic treatment of the injured vertebra(e), internal fixation of the vertebral column, and bilateral laminectomy for epidural decompression were followed directly by neurosurgical management, including separation of the arachnoid adhesion to restore cerebrospinal fluid flow and debridement of the spinal cord necrotic tissue with concomitant intramedullary decompression. Rehabilitation started 17 days after the operation. The final outcome was evaluated after 3 months of rehabilitation. Pearson chi-square analysis was used for statistical analysis. Results All the patients recovered some ability to walk. The least recovered patients were able to walk with a wheeled weight support and help in stabilizing the weight bearing knee joint (12 cases, 40%). Thirteen patients (43%) were able to walk with a pair of crutches, a stick or without any support. The timing of the operation after injury was important. An optimal operation time window was identified at 4-14 days after injury. Conclusions Early neurosurgical intervention of spinal cord contusion followed by rehabilitation can significantly improve the locomotion of the patients. It is a new idea of a therapeutic approach for spinal cord contusion and has been proven to be very successful. 展开更多
关键词 spinal cord CONTUSION NEUROSURGERY REHABILITATION
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Degradation kinetics and mechanism of aniline by heat-assisted persulfate oxidation 被引量:26
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作者 Xiaofang Xie Yongqing Zhang +1 位作者 Weilin Huang Shaobing Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第5期821-826,共6页
Oxidation of aniline by persulfate in aqueous solutions was investigated and the reaction kinetic rates under different temperature, persulfate concentration and pH conditions were examined in batch experiments. The r... Oxidation of aniline by persulfate in aqueous solutions was investigated and the reaction kinetic rates under different temperature, persulfate concentration and pH conditions were examined in batch experiments. The results showed that, the aniline degradation followed pseudo first-order reaction model. Aniline degradation rate increased with increasing temperature or persulfate concentration. In the pH range of 3 to 11, a low aniline degradation rate was obtained at strong acid system (pH 3), while a high degradation rate was achieved at strong alkalinity (pH 11). Maximum aniline degradation occurred at pH 7 when the solution was in a weak level of acid and alkalinity (pH 5, 7 and 9). Produced intermediates during the oxidation process were identified using liquid chromatography-mass spectrometry technology. And nitrobenzene, 4-4’-diaminodiphenyl and 1-hydroxy-1,2-diphenylhydrazine have been identified as the major intermediates of aniline oxidation by persulfate and the degradation mechanism of aniline was also tentatively proposed. 展开更多
关键词 PERSULFATE OXIDATION KINETIC mechanism ANILINE
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Tumor suppressor p53 and metabolism 被引量:23
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作者 Juan Liu Cen Zhang +1 位作者 Wenwei Hu Zhaohui Feng 《Journal of Molecular Cell Biology》 SCIE CAS CSCD 2019年第4期284-292,共9页
p53 plays a key role in tumor suppression. The tumor suppressive function of p53 has long been attributed to its ability to induce apoptosis, cell cycle arrest, and senescence in cells. However, recent studies suggest... p53 plays a key role in tumor suppression. The tumor suppressive function of p53 has long been attributed to its ability to induce apoptosis, cell cycle arrest, and senescence in cells. However, recent studies suggest that other functions of p53 also contribute to its role as a tumor suppressor, such as its function in metabolic regulation. p53 regulates various metabolic pathways to maintain the metabolic homeostasis of cells and adapt cells to stress. In addition, recent studies have also shown that gain-offunction (GOF) mutant p53 proteins drive metabolic reprogramming in cancer cells, contributing to cancer progression. Further understanding of p53 and its GOF mutants in metabolism will provide new opportunities for cancer therapy. 展开更多
关键词 P53 tumor SUPPRESSOR MUTANT P53 GAIN-OF-FUNCTION METABOLISM
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茶黄素双没食子酸酯的抗癌活性及其作用机理研究 被引量:25
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作者 江和源 Hang Xiao +2 位作者 袁新跃 王川丕 Chung S Yang 《茶叶科学》 CAS CSCD 北大核心 2007年第1期33-38,44,共7页
以SephadexLH-20柱色谱分离得到茶黄素双没食子酸酯(TFDG)成分,以H1299和HCT-116细胞分析了该成分的抗癌活性及其作用机理。结果表明,TFDG具有良好的抑制H1299细胞生长的活性,IC50为25μmol/L;有调节细胞周期的活性,可增加HCT-116细胞G... 以SephadexLH-20柱色谱分离得到茶黄素双没食子酸酯(TFDG)成分,以H1299和HCT-116细胞分析了该成分的抗癌活性及其作用机理。结果表明,TFDG具有良好的抑制H1299细胞生长的活性,IC50为25μmol/L;有调节细胞周期的活性,可增加HCT-116细胞G1期细胞的比例;有促进HCT-116细胞凋亡的作用,浓度为50μmol/L时效果显著,48h凋亡率达到40%以上;Western杂交技术分析结果表明,它可降低HCT-116细胞中促癌蛋白质因子Bcl-xL的表达量,可增加抑癌蛋白质因子Bax的表达量。 展开更多
关键词 茶黄素 抗癌 细胞周期 凋亡 蛋白质印迹
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农户劳动力禀赋、农地规模与农机社会化服务采纳行为分析——来自豫鲁冀的证据 被引量:23
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作者 曾雅婷 Jin Yanhong 吕亚荣 《农业现代化研究》 CSCD 北大核心 2017年第6期955-962,共8页
推动农业生产机械化对实现我国农业供给侧改革有重要意义,农机社会化服务则是有中国特色的实现农业机械化的有效方式。基于农户采纳农机社会化服务数理分析,利用豫鲁冀三省594个农户的实地调研数据,运用似不相关回归、多元线性回归模型... 推动农业生产机械化对实现我国农业供给侧改革有重要意义,农机社会化服务则是有中国特色的实现农业机械化的有效方式。基于农户采纳农机社会化服务数理分析,利用豫鲁冀三省594个农户的实地调研数据,运用似不相关回归、多元线性回归模型,分析了家庭资源禀赋对农户采纳农机社会化服务的影响。结果表明,样本农户玉米生产农机社会化服务使用率为57.9%,而自有农机使用率仅为3.20%。农户家庭农业劳动力数量与农机社会化服务使用率之间负相关、非农劳动力数量与农机社会化服务使用率之间正相关,劳动力质量与农机社会化服务使用率之间正相关;农地规模与农机社会化服务使用率之间呈倒"U"型关系,但与自有机械使用率、总机械化率呈显著正相关。因此,提出完善农机社会化服务市场、提高农业劳动力质量、加快土地流转市场建设、降低农地细碎化水平等对策建议。 展开更多
关键词 劳动力禀赋 农地规模 农机社会化服务 土地流转 似不相关回归(SUR)
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Farnesoid X receptor,the bile acid sensing nuclear receptor,in liver regeneration 被引量:21
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作者 Guodong Li Grace L.Guo 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2015年第2期93-98,共6页
The liver is unique in regenerative potential, which could recover the lost mass and function after injury from ischemia and resection. The underlying molecular mechanisms of liver regeneration have been extensively s... The liver is unique in regenerative potential, which could recover the lost mass and function after injury from ischemia and resection. The underlying molecular mechanisms of liver regeneration have been extensively studied in the past using the partial hepatectomy(PH) model in rodents, where 2/3 PH is carried out by removing two lobes. The whole process of liver regeneration is complicated, orchestrated event involving a network of connected interactions, which still remain fully elusive. Bile acids(BAs) are ligands of farnesoid X receptor(FXR), a nuclear receptor of ligand-activated transcription factor. FXR has been shown to be highly involved in liver regeneration. BAs and FXR not only interact with each other but also regulate various downstream targets independently during liver regeneration. Moreover, recent findings suggest that tissue-specific FXR also contributes to liver regeneration significantly. These novel findings suggest that FXR has much broader role than regulating BA, cholesterol, lipid and glucose metabolism. Therefore, these researches highlight FXR as an important pharmaceutical target for potentialuse of FXR ligands to regulate liver regeneration in clinic. This review focuses on the roles of BAs and FXR in liver regeneration and the current underlying molecular mechanisms which contribute to liver regeneration. 展开更多
关键词 Farnesoid X receptor Liver regeneration Bile acids Fibroblast growth factor 15 Liver-intestine croass talk Transmembrane G protein coupled receptor 5
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In situ chemical oxidation of aniline by persulfate with iron(Ⅱ) activation at ambient temperature 被引量:18
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作者 Yong Qing Zhang Wei Lin Huang Donna E.Fennell 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期911-913,共3页
The kinetics of aniline degradation by persulfate processes with iron(Ⅱ) activation at ambient temperature was investigated in this study.With iron(Ⅱ) as initiator,the oxidation reactions were found to follow a ... The kinetics of aniline degradation by persulfate processes with iron(Ⅱ) activation at ambient temperature was investigated in this study.With iron(Ⅱ) as initiator,the oxidation reactions were found to follow a biphasic rate phenomenon:a rapid transformation followed by a slow but sustained oxidation process.In the first 30 s,the reaction mainly relies on the persulfate-Fe^(2+) reaction in which aniline is oxidized rapidly.After 30 s,the aniline was still oxidized but the rate of reaction tended to be slower and the rates were clearly linear-proportional.After the initial fast oxidation,the reactions appeared to follow a pseudo-first-order model. 展开更多
关键词 PERSULFATE ANILINE In situ chemical oxidation
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Heterologous biosynthesis of natural product naringenin by co-culture engineering 被引量:17
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作者 Vijaydev Ganesan Zhenghong Li +1 位作者 Xiaonan Wang Haoran Zhang 《Synthetic and Systems Biotechnology》 SCIE 2017年第3期236-242,共7页
Co-culture engineering is an emerging approach for microbial biosynthesis of a variety of biochemicals.In this study,E.coli-E.coli co-cultures were developed for heterologous biosynthesis of the natural product naring... Co-culture engineering is an emerging approach for microbial biosynthesis of a variety of biochemicals.In this study,E.coli-E.coli co-cultures were developed for heterologous biosynthesis of the natural product naringenin.The co-cultures were composed of two independent E.coli strains dedicated to functional expression of different portions of the biosynthetic pathway,respectively.The co-culture biosynthesis was optimized by investigating the effect of carbon source,E.coli strain selection,timing of IPTG induction and the inoculation ratio between the co-culture strains.Compared with the monoculture strategy,the utilization of the designed co-cultures significantly improved the naringenin production,largely due to the reduction of metabolic stress,employment of proper hosts for improving pathway enzyme activities,and flexible adjustment of the relative biosynthetic strength between the coculture strains.The findings of this study extend the applicability of co-culture engineering in complex natural product biosynthesis. 展开更多
关键词 Co-culture engineering NARINGENIN Heterologous biosynthesis E.COLI
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Use of curcumin in diagnosis,prevention,and treatment of Alzheimer's disease 被引量:14
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作者 Min Chen Zhi-Yun Du +3 位作者 Xi Zheng Dong-Li Li Ren-Ping Zhou Kun Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第4期742-752,共11页
This review summarizes and describes the use of curcumin in diagnosis,prevention,and treatment of Alzheimer's disease.For diagnosis of Alzheimer's disease,amyloid-β and highly phosphorylated tau protein are the maj... This review summarizes and describes the use of curcumin in diagnosis,prevention,and treatment of Alzheimer's disease.For diagnosis of Alzheimer's disease,amyloid-β and highly phosphorylated tau protein are the major biomarkers.Curcumin was developed as an early diagnostic probe based on its natural fluorescence and high binding affinity to amyloid-β.Because of its multi-target effects,curcumin has protective and preventive effects on many chronic diseases such as cerebrovascular disease,hypertension,and hyperlipidemia.For prevention and treatment of Alzheimer's disease,curcumin has been shown to effectively maintain the normal structure and function of cerebral vessels,mitochondria,and synapses,reduce risk factors for a variety of chronic diseases,and decrease the risk of Alzheimer's disease.The effect of curcumin on Alzheimer's disease involves multiple signaling pathways:anti-amyloid and metal iron chelating properties,antioxidation and anti-inflammatory activities.Indeed,there is a scientific basis for the rational application of curcumin in prevention and treatment of Alzheimer's disease. 展开更多
关键词 nerve regeneration CURCUMIN Alzheimer's disease senile dementia early diagnosis positron emission tomography magnetic resonance imaging biological availability chemical components NEURODEGENERATION neural regeneration
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A decade of Bt cotton in Chinese fields: Assessing the direct effects and indirect externalities of Bt cotton adoption in China 被引量:13
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作者 Scott ROZELLE Carl PRAY 《Science China(Life Sciences)》 SCIE CAS 2010年第8期981-991,共11页
The objective of this study is to examine whether or not the gains from reduced spraying for bollworms are being sustained more than one decade after the initial adoption in 2007. Based on farm-level data collected by... The objective of this study is to examine whether or not the gains from reduced spraying for bollworms are being sustained more than one decade after the initial adoption in 2007. Based on farm-level data collected by the authors in 1999–2007 in 16 villages from 4 provinces, this study shows that insecticides applied for controlling bollworms have declined. This analysis supports Chinese policy makers’ decision to not require refuges of non-Bt cotton fields. It also suggests that past studies may have underestimated the benefits from adopting Bt technology. 展开更多
关键词 BIOTECHNOLOGY BT COTTON INSECTICIDE SUSTAINABILITY externalities China
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Temperature effect on the kinetics of persulfate oxidation of p-chloroaniline 被引量:13
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作者 Yong Qing Zhang Xiao Zhe Du Wei Lin Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第3期358-361,共4页
The kinetics of heat-facilitated persulfate oxidation of p-chloroaniline(PCA) in aqueous solutions was measured at five different temperature conditions and at four different oxidant concentrations.The PCA degradati... The kinetics of heat-facilitated persulfate oxidation of p-chloroaniline(PCA) in aqueous solutions was measured at five different temperature conditions and at four different oxidant concentrations.The PCA degradation was found to follow a pseudo-first-order decay model when the persulfate was excessive.The pseudo-first-order rate constants of PCA degradation by persulfate(50 mmol/ L) at pH 7.0 are 0.12×10^-4,0.28×10^-4,0.43×10^-4,0.83×10^-4,1.32×10^-4 s^-1 at 10,20,30,40 and 50℃,respectively. Under the above reaction conditions,the reaction has activation energy of 49.97 kJ/mol.The observed rate was found to be function of temperature and oxidant concentration.Raising temperature and increasing persulfate concentration can significantly accelerate the PCA degradation. 展开更多
关键词 PERSULFATE P-CHLOROANILINE KINETICS In situ chemical oxidation TEMPERATURE
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中国10年抗虫棉大田生产:Bt抗虫棉技术采用的直接效应和间接外部效应评估 被引量:11
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作者 黄季煜 米建伟 +5 位作者 林海 王子军 陈瑞剑 胡瑞法 ROZELLE Scott PRAY Carl 《中国科学:生命科学》 CSCD 北大核心 2010年第3期260-272,共13页
中国自1997年便开始大面积种植Bt抗虫棉.本研究试图分析中国种植抗虫棉10年后减少防治棉铃虫杀虫剂用量的可持续性.通过对1999~2007年4个省16个村农户大田Bt抗虫棉生产的跟踪调查数据分析,发现生产上控制棉铃虫的杀虫剂用量不仅未增加,... 中国自1997年便开始大面积种植Bt抗虫棉.本研究试图分析中国种植抗虫棉10年后减少防治棉铃虫杀虫剂用量的可持续性.通过对1999~2007年4个省16个村农户大田Bt抗虫棉生产的跟踪调查数据分析,发现生产上控制棉铃虫的杀虫剂用量不仅未增加,反而呈下降趋势;虽然没有直接回答Bt抗虫棉能够维持并增加其生产率的机理,但本研究发现,10年来不仅抗虫棉,而且非抗虫棉防治棉铃虫的杀虫剂用量也显著减少,这与抗虫棉广泛种植后棉铃虫的种群总量下降有关.这些发现对于Bt技术效应分析具有重要意义,同时,本文所采用的同时评估抗虫转基因技术生产的直接效应和间接外部性效应的方法,对于未来该领域的同类研究也具有借鉴意义. 展开更多
关键词 生物技术 BT抗虫棉 杀虫剂 可持续性 外部性 中国
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Degradation of aniline by Fe^(2+)-activated persulfate oxidation at ambient temperature 被引量:12
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作者 张永清 谢晓芳 +1 位作者 黄伟林 黄少斌 《Journal of Central South University》 SCIE EI CAS 2013年第4期1010-1014,共5页
The aniline degradation by persulfate activated with ferrous ion (Fe2+ ) was investigated in batch reactor at ambient temperature. The experimental factors in aqueous solutions including persulfate concentration, Fe2+... The aniline degradation by persulfate activated with ferrous ion (Fe2+ ) was investigated in batch reactor at ambient temperature. The experimental factors in aqueous solutions including persulfate concentration, Fe2+ concentration, pH and ionic strength level were discussed. It is demonstrated that, aniline degradation rate increases with increasing persulfate concentration, but much more ferrous ion inhibits the aniline degradation. When the aniline concentration is 0.10 mmol/L, the maximum aniline degradation occurs at the S2O82- to Fe2+ molar ratio of 250/5 at pH 7.0. In the pH range of 5.0-8.5, increasing pH causes higher aniline degradation. What's more, the increase of ionic strength in solution causes inhibiting in the reaction. Produced intermediates during the oxidation process were identified using gas chromatography-mass spectrometry (GC-MS) technology. And degradation pathways of aniline were also tentatively proposed. 展开更多
关键词 ANILINE ferrous ion PERSULFATE DEGRADATION
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乌苏酸联合吉西他滨对胰腺癌PANC-1细胞增殖和凋亡的影响 被引量:12
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作者 江森 郑希 +2 位作者 何燕 Tina LIAO 张焜 《中国肿瘤生物治疗杂志》 CAS CSCD 北大核心 2018年第3期252-257,共6页
目的:探讨乌苏酸联合吉西他滨对胰腺癌PANC-1细胞增殖和凋亡的影响。方法:以乌苏酸、吉西他滨单独用药作用于体外培养的胰腺癌细胞PANC-1细胞,采用细MTT法检测细胞半抑制浓度(IC_(50)),确定药物给药浓度;以乌苏酸(2μmol/L)、吉西他滨(... 目的:探讨乌苏酸联合吉西他滨对胰腺癌PANC-1细胞增殖和凋亡的影响。方法:以乌苏酸、吉西他滨单独用药作用于体外培养的胰腺癌细胞PANC-1细胞,采用细MTT法检测细胞半抑制浓度(IC_(50)),确定药物给药浓度;以乌苏酸(2μmol/L)、吉西他滨(0.2μmol/L)单独及联合作用于PANC-1细胞,采用锥虫蓝染色法检测PANC-1细胞存活率,PI染色后PANC-1细胞中检测细胞凋亡,采用细胞划痕实验检测PANC-1细胞迁移和伤口愈合情况,采用Western blotting检测对照组、乌苏酸组与吉西他滨组单独及联合用药组细胞中P-JNK、Bcl-2、IL-6、P-Stat 3、NF-κB和Cox-2蛋白的表达。结果:乌苏酸和吉西他滨对胰腺癌PANC-1细胞均有较强的抑制作用,其IC_(50)分别是13.67和2.78μmol/L,据此选择它们的实验浓度分别为2和0.2μmol/L。两者联合用药比分别单独用药能更显著抑制癌细胞的增殖活性[(46.47±5.07)%vs(78.38±8.65)%、(76.12±3.23)%,均P<0.05],能更明显诱导癌细胞凋亡[(39.78±7.01)%vs(20.35±8.51)%、(20.35±8.51)%,均P<0.01]和抑制细胞迁移能力(P<0.01),同时更显著抑制凋亡相关蛋白Bcl-2、IL-6的表达及促进P-JNK的表达。结论:乌苏酸和吉西他滨协同增强抑制胰腺癌PANC-1细胞的增殖和迁移以及促凋亡作用,其机制可能与抑制Bcl-2、IL-6、P-Stat 3和促进P-JNK蛋白表达有关。 展开更多
关键词 胰腺癌 乌苏酸 吉西他滨 增殖 迁移 凋亡
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