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氧自由基及其清除剂 被引量:28
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作者 陈海光 叶丹杰 《仲恺农业技术学院学报》 2002年第1期53-60,共8页
对氧自由基的产生、性质及检测方法进行综述 ,并介绍了氧自由基清除剂的种类、作用机理及应用 有关研究表明 。
关键词 清除剂 抗氧化剂 作用机理 人体 物理 化学 疾病防治 氧自由基 自由基清除剂
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Fenton反应产生的羟自由基及其清除的电化学方法测定 被引量:12
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作者 邰超 邹洪 +1 位作者 谷学新 郭启华 《分析测试学报》 CAS CSCD 北大核心 2002年第5期30-32,共3页
建立了一种新的测定羟自由基的电化学方法 ,Fenton反应产生的羟自由基氧化二甲亚砜 (DMSO)生成的甲醛与乙酰丙酮、氨发生Hantzsch反应 ,产物3,5_二乙酰基_1,4_二氢吡啶在 -1.20V(vsSCE)处有一灵敏的二阶导数极谱波 ,通过峰电流变化可间... 建立了一种新的测定羟自由基的电化学方法 ,Fenton反应产生的羟自由基氧化二甲亚砜 (DMSO)生成的甲醛与乙酰丙酮、氨发生Hantzsch反应 ,产物3,5_二乙酰基_1,4_二氢吡啶在 -1.20V(vsSCE)处有一灵敏的二阶导数极谱波 ,通过峰电流变化可间接测定羟自由基 ;拟定的方法测定了数种清除剂与羟自由基反应的反应速率常量和清除羟自由基的IC50;该法简便可靠 。 展开更多
关键词 FENTON反应 电化学方法 测定 羟自由基 清除剂 Hantzsch反应 极谱法
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广州拾荒者的身体实践与空间建构 被引量:20
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作者 陶伟 王绍续 朱竑 《地理学报》 EI CSSCI CSCD 北大核心 2017年第12期2199-2213,共15页
20世纪90年代以来,身体地理学在女性主义的推动下迅速兴起,建立了以身心一元论为基础的研究路径。延循后现代主义的研究范式,身体研究更重视身体在感知世界、生产知识和占据空间过程中所发挥的重要作用,把身体视为挑战主流文化并为边缘... 20世纪90年代以来,身体地理学在女性主义的推动下迅速兴起,建立了以身心一元论为基础的研究路径。延循后现代主义的研究范式,身体研究更重视身体在感知世界、生产知识和占据空间过程中所发挥的重要作用,把身体视为挑战主流文化并为边缘群体发声的武器。以城市边缘群体为研究对象,采取深度访谈和参与式观察方法,对广州拾荒者群体的个案展开研究,旨在探索拾荒者如何在城市中占据生活工作空间,以及分析拾荒者所占据场所的空间特征和结构。研究发现:(1)拾荒者运用自我身体实践,发挥个体能动性,成功地在现代化都市建设过程中完成了自我物质空间的建构;身体实践在社会底层群体占据城市空间过程中具有重要作用。关注拾荒者的身体实践为理解城市边缘群体的需求以及探究身体与地方的互动提供了新的路径。(2)拾荒者借助地缘关系、业缘关系和庇护关系,形成了渗透到城市空间中独特的拾荒者聚集区,建立起了空间边界相互交错,但收购权力划分明确的工作"地盘",使城市规划所定义的城市空间转变成了融合城乡因素的混合空间。拾荒者聚集区的建立,展示了城市边缘群体身体实践对地方的重构过程。研究对身体地理学在中国的实证具有开拓意义。 展开更多
关键词 拾荒者 身体实践 空间建构 社会关系 聚集区 广州
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脉冲放电等离子体水处理体系中·OH的作用 被引量:18
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作者 王慧娟 李杰 《高电压技术》 EI CAS CSCD 北大核心 2013年第7期1698-1702,共5页
为了证明羟基自由基(·OH)在脉冲放电等离子体降解有机物过程中具有重要作用,以苯酚作为目标物,研究了在添加了不同自由基捕收剂条件下,分别以空气和氧气(O2)为载气的脉冲放电等离子体体系中苯酚的降解效率和能量效率,并对相同实验... 为了证明羟基自由基(·OH)在脉冲放电等离子体降解有机物过程中具有重要作用,以苯酚作为目标物,研究了在添加了不同自由基捕收剂条件下,分别以空气和氧气(O2)为载气的脉冲放电等离子体体系中苯酚的降解效率和能量效率,并对相同实验条件下纯水体系中脉冲放电产生的过氧化氢(H2O2)浓度进行了测定。研究结果表明:在空气和O22种载气下,随着添加的捕收剂(Na2CO3和正丁醇)浓度的增加,脉冲放电过程中苯酚的降解效率和能量效率呈下降趋势,证明·OH在脉冲放电降解有机物过程中具有重要作用。此外,添加正丁醇后的H2O2测定结果验证了捕收剂对·OH的捕收作用。 展开更多
关键词 脉冲放电 等离子体 ·OH 苯酚 捕收剂 H2O2
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Effect of melatonin on the severity of L-arginine-induced experimental acute pancreatitis in rats 被引量:13
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作者 Annamaria Szabolcs Russel J Reiter +9 位作者 Tamas Letoha Peter Hegyi Gabor Papai Ilona Varga Katalin Jarmay Jozsef Kaszaki Reka Sari Zoltan Rakonczay Jr Janos Lonovics Tamas Takacs 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第2期251-258,共8页
AIM: To determine the effect of melatonin pre- and post-treatment on the severity of L-arginine (L-Arg) -induced experimental pancreatitis in rats. METHODS: Male Wistar rats (25) were divided into five groups. T... AIM: To determine the effect of melatonin pre- and post-treatment on the severity of L-arginine (L-Arg) -induced experimental pancreatitis in rats. METHODS: Male Wistar rats (25) were divided into five groups. Those in group A received two injections of 3.2 g/kg body weight L-Arg i.p. at an interval of 1 h. In group MA, the rats were treated with 50 mg/kg body weight melatonin i.p. 30 min prior to L-Arg administration. In group AM, the rats received the same dose of melatonin 1 h after L-Arg was given. In group M, a single dose of melatonin was administered as described previously. In group C the control animals received physiological saline injections i.p. All rats were exsanguinated 24 h after the second L-Arg injection. RESULTS: L-Arg administration caused severe necrotizing pancreatitis confirmed by the significant elevations in the serum amylase level, the pancreatic weight/body weight ratio (pw/bw), the pancreatic IL-6 content and the myeloperoxidase activity, relative to the control values. Elevation of the serum amylase level was significantly reduced in rats given melatonin following L-Arg compared to rats injected with L-Arg only. The activities of the pancreatic antioxidant enzymes (Cu/Zn-superoxide dismutase (CulZn-SOD) and catalase (CAT)) were significantly increased 24 h after pancreatitis induction. Melatonin given in advance of L-Arg significantly reduced the pancreatic CAT activity relative to that in the rats treated with L-Arg alone. In the liver, L-Arg significantly increased the lipid peroxidation level, and the glutathione peroxidase and Cu/Zn-SOD activities, whereas the Mn-SOD activity was reduced as compared to the control rats. Melatonin pre-treatment prevented these changes. CONCLUSION: Melatonin is an antioxidant that is able to counteract some of the L-Arg-induced changes during acute pancreatitis, and may therefore be helpful in the supportive therapy of patients with acute necrotizing pancreatitis. 展开更多
关键词 Acute pancreatitis MELATONIN scavengers
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各种自由基清除剂在γ射线辐照DNA损伤中的作用 被引量:10
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作者 杨明建 孔福全 +5 位作者 展永 王潇 倪嵋楠 隋丽 蔡明辉 赵葵 《核技术》 CAS CSCD 北大核心 2007年第4期255-258,共4页
为了对重离子辐照致DNA损伤中的自由基作用进行评估,本文利用γ射线对添加了各种自由基清除剂(甘露醇,维生素C和茶多酚)的质粒DNA进行辐照,凝胶电泳分析的结果表明,三种自由基清除剂对DNA均有很好的保护作用。在相同自由基清除剂浓度的... 为了对重离子辐照致DNA损伤中的自由基作用进行评估,本文利用γ射线对添加了各种自由基清除剂(甘露醇,维生素C和茶多酚)的质粒DNA进行辐照,凝胶电泳分析的结果表明,三种自由基清除剂对DNA均有很好的保护作用。在相同自由基清除剂浓度的情况下,甘露醇比维生素C具有更强的清除自由基的作用。与重离子辐照情况相比,这几种自由基清除剂对γ射线产生的自由基的清除作用更为明显。 展开更多
关键词 自由基 自由基清除剂 甘露醇 微生素C 茶多酚 Γ射线 质粒DNA 凝胶电泳
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乙烯清除剂在果蔬保鲜中的研究进展 被引量:8
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作者 王超 杨子明 +3 位作者 何祖宇 周闯 刘运浩 李普旺 《保鲜与加工》 CAS 2022年第9期82-88,共7页
乙烯作为一种催熟果蔬的植物激素,能够通过催熟果蔬改善其风味和品质,但也会加速果蔬的腐烂,因此合理有效的控制果蔬在贮藏、运输等过程中乙烯的含量对延长果蔬货架期,保持果蔬新鲜度具有重要意义。针对乙烯清除剂在果蔬保鲜方面的研究... 乙烯作为一种催熟果蔬的植物激素,能够通过催熟果蔬改善其风味和品质,但也会加速果蔬的腐烂,因此合理有效的控制果蔬在贮藏、运输等过程中乙烯的含量对延长果蔬货架期,保持果蔬新鲜度具有重要意义。针对乙烯清除剂在果蔬保鲜方面的研究进行了综述,对通过物理方法、化学方法和乙烯生物合成抑制方法制备的不同乙烯清除剂的应用进行了阐述。 展开更多
关键词 乙烯 吸附 清除剂 保鲜 果蔬
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N-acetylcysteine attenuates alcohol-induced oxidative stress in the rat 被引量:7
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作者 Resat Ozaras Veysel Tahan +3 位作者 Seval Aydin Hafize Uzun Safiye Kaya Hakan Senturk 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第1期125-128,共4页
AIM: There is increasing evidence that alcohol-induced liverdamage may be associated with increased oxidative stress.We aimed to investigate free-radical scavenger effect of n-acetylcysteine in rats intragastrically f... AIM: There is increasing evidence that alcohol-induced liverdamage may be associated with increased oxidative stress.We aimed to investigate free-radical scavenger effect of n-acetylcysteine in rats intragastrically fed with ethanol.METHODS: Twenty-four rats divided into three groups werefed with ethanol (6 g/kg/day, Group 1), ethanol and n-acetylcysteine (1 g/kg, Group 2), or isocaloric dextrose(control group, Group 3) for 4 weeks. Then animals weresacrificed under ether anesthesia, intracardiac blood andliver tissues were obtained. Measurements were performedboth in serum and in homogenized liver tissues.Malondialdehyde (MDA) level was measured by TBARSmethod. Glutathione peroxidase (GSH-Px) and superoxidedismutase (SOD) levels were studied by commercial kits.Kruskal-Wallis test was used for statistical analysis.RESULTS: ALT and AST in Group 1 (154 U/Land 302 U/L,respectively) were higher than those in Group 2 (94 U/L and155 U/L) and Group 3 (99 U/L and 168 U/L) (P=0.001 forboth). Serum and tissue levels of MDA in Group 1 (1.84 nmol/mL and 96 nmol/100 mg-protein) were higher than Group 2(0.91 nmol/mL and 64 nmol/100 mg-protein) and Group 3(0.94 nmol/mL and 49 nmol/100 mg-protein) (P<0.001 forboth). On the other hand, serum GSH-Px level in Group 1(8.21 U/g-Hb) was lower than Group 2 (16 U/g-Hb) andGroup 3 (16 U/g-Hb) (P<0.001). Serum and liver tissue levelsof SOD in Group 1 (11 U/mL and 26 U/100 mg-protein)were lower than Group 2 (18 U/mL and 60 U/100 mg-protein)and Group 3 (20 U/mL and 60 U/100 mg-protein) (P<0.001for both).CONCLUSION: This study demonstrated that ethanol-induced liver damage is associated with oxidative stress,and co-administration of n-acetylcysteine attenuates thisdamage effectively in rat model. 展开更多
关键词 Oxidative Stress ACETYLCYSTEINE Animals Erythrocytes Ethanol dosage Free Radical scavengers GLUTATHIONE Glutathione Peroxidase Lipid Peroxidation Liver Male RATS Rats Wistar Research Support Non-U.S. Gov't Superoxide Dismutase Thiobarbituric Acid Reactive Substances
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In comparison with vitamin C and butylated hydroxytoluene, the antioxidant capacity of aqueous extracts from buds and flowers of Lonicera japonica Thunb. 被引量:4
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作者 Zhou Yunfeng Li Lin +2 位作者 Sun Lan Zhou Lidong Xu Yang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2018年第3期373-379,共7页
OBJECTIVE: To assess the antioxidant capacity of aqueous extracts of buds and flowers of Lonicera japonica Thunb.(BLJ and FLJ) using in vitro assays.METHODS: We assessed the in vitro antioxidant activities of aqueous ... OBJECTIVE: To assess the antioxidant capacity of aqueous extracts of buds and flowers of Lonicera japonica Thunb.(BLJ and FLJ) using in vitro assays.METHODS: We assessed the in vitro antioxidant activities of aqueous extracts of BLJ and FLJ and compared with that of classical antioxidants vitamin C and butylated hydroxytoluene, using several well-established methods including the 1,1-diphenyl-2-picryl-hydrazyl assay, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) assay, reducing power assay, fluorescence recovery after photobleaching assay, β-carotene bleaching assay, ferric thiocyanate assay, and thiobarbituric acid method.RESULTS: The aqueous extracts of both BLJ and FLJ had similarly potent antioxidant capacity. There were no significance differences between BLJ and FLJ in all the assays.CONCLUSION: The aqueous extracts of both BLJ and FLJ have antioxidant activity with comparable efficacy. These findings suggest that both BLJ and FLJ may have the potential as natural antioxidants. 展开更多
关键词 BUDS FLOWERS LONICERA JAPONICA Freeradical scavengers Lipid PEROXIDATION
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上海市生活垃圾分类政策实施中问题的分析 被引量:6
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作者 王垚 王子彦 《环境保护科学》 CAS 2020年第3期18-22,共5页
文章对上海市垃圾分类管理条例推行中所遇问题进行分析。结果表明:条例内容的逻辑性及群众对条例的接受度是影响实施效果的主要原因,同时提出条例推行是否会对拾荒者生存产生一定影响的思考。在结合国外垃圾分类经验基础上为我国各大城... 文章对上海市垃圾分类管理条例推行中所遇问题进行分析。结果表明:条例内容的逻辑性及群众对条例的接受度是影响实施效果的主要原因,同时提出条例推行是否会对拾荒者生存产生一定影响的思考。在结合国外垃圾分类经验基础上为我国各大城市推进垃圾分类政策、开展我国环境保护工作、培养群众行为道德意识提供参考。 展开更多
关键词 垃圾分类 拾荒者 环境保护 资源利用 群体接受度
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Effect of Danhong injection on expressions of macrophage scavenger receptor 1 and sub-family A member 1 in human U937 cells 被引量:6
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作者 Xianming Su Wei Yang Xiaowen Zhi 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第3期384-387,共4页
OBJECTIVE: To study the effects of Danhong injec- tion (DHI) on expression of the macrophage scaven- ger receptor 1 (MSR1) and ATP-binding cassette, sub-family A member 1 (ABCA1) genes, which en- code scavenger... OBJECTIVE: To study the effects of Danhong injec- tion (DHI) on expression of the macrophage scaven- ger receptor 1 (MSR1) and ATP-binding cassette, sub-family A member 1 (ABCA1) genes, which en- code scavenger receptor-A I (SR-AI) and ATP-bind- ing cassette transporter 1 (ABCA1), respectively, as a potential anti-atherosclerotic mechanism. METHODS: Human U937 cells were stimulated by in- cubation with 100 nM phorbo112-myristate 13-ace- tate (PMA) for 48 h.These stimulated, monocyte-like cells were then incubated for 24 h with 50 mg/L oxi- dized low-density lipoprotein (ox-LDL, to induce foam cell formation), together with a liver X recep- tor (LXR) agonist or with different DHI concentra- tions. MSR1 and ABCA1 mRNA levels were mea- sured by fluorescence-based quantitative PCR. RESULTS: Compared with control cells (which re- ceived only ox-LDL), cells treated with both ox-LDL and 10 IJmol/L LXR agonist showed lower MSR1 ex-pression (but this effect was not statistically signifi- cant, P〉0.05) and higher ABCA1 expression (P〈 0.01). Cells that received ox-LDL and 3 mL/L DHI possessed higher MSR1 mRNA levels than the con- trols, whereas cells treated with ox-LDL and higher DHI concentrations (10, 30 or 60 mL/L) showed low- er MSR1 expression levels (but the differences ob- served between DHI concentration groups were not statistically significant, P〉0.05). ABCA1 expression in cells treated with ox-LDL and 3, 10 or 30 mL/L DHI was higher than in the control cells, and increased with increasing DHI concentration (P〈0.05). ABCA1 expression in cells treated with ox-LDL and the highest DHI concentration tested (60 mL/L) was not significantly different from that in the controls. ABCA1 mRNA levels in cells treated with ox-LDL and DHI were similar to, or lower than, those in cells treated with ox-LDL and the LXR agonist. CONCLUSION: DHI does not affect MSR1 mRNA lev- els in ox-LDL-treated U937 cells. However, at certain concentrations (10 and 30 m 展开更多
关键词 Receptors scavengers Class A ATP-binding cassette transporters Cholesterol me-tabolism U937 cells Danhong injection
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Prevention of grafted liver from reperfusive injury 被引量:4
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作者 Kai Ma Yang Yu Xian-Min Bu Yan-Jun Li Xian-Wei Dai Liang Wang Yang Dai Hai-Ying Zhao Xiang-Hong Yang Department of General Surgery,Second Clinical College,China Medical University,Shenyang 110003,Liaoning Province,ChinaDepartrnent of Physiology,Shenyang Physical Education College,Shenyang,Liaoning Province,ChinaDepartment of Pathology,China Medical University,Shenyang,Liaoning Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第4期572-574,共3页
INTRODUCTIONThe incidence of primary non-function(PNF)of grafted liver in the early postoperative stage is 2%-23%[1-4],its main cause is the ischemic-rechemic injure[5,6].In this experiment,anisodamine was added into ... INTRODUCTIONThe incidence of primary non-function(PNF)of grafted liver in the early postoperative stage is 2%-23%[1-4],its main cause is the ischemic-rechemic injure[5,6].In this experiment,anisodamine was added into the preserving fluid and the grafted liver was rewarmed at different temperatures to protect the cell membranc and prevent ischemic-reperfusive injury. 展开更多
关键词 Liver Transplantation Animals Body Temperature Drugs Chinese Herbal Free Radical scavengers HEPATOCYTES Lipid Peroxidation LIVER Male Microscopy Electron RATS Rats Wistar Reactive Oxygen Species Reperfusion Injury control Research Support Non-U.S. Gov't Solanaceous Alkaloids Superoxide Dismutase
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亚硝酸盐清除剂研究进展及其在肉制品中的应用 被引量:1
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作者 赵长青 代锦苹 +6 位作者 方春玉 刘世欣 朱荣贵 冉光雨 郭志强 周云川 赵志峰 《中国调味品》 CAS 北大核心 2024年第1期198-202,220,共6页
亚硝酸盐在食品工业,尤其是在肉制品加工工业中具有抑菌、抗氧化、赋予肉制品特殊风味及发色等重要作用。然而,亚硝酸盐的摄入超出正常范围会造成身体组织的氧气不足,还可形成亚硝胺,最终引发癌症,但目前还未发现单一物质可替代亚硝酸... 亚硝酸盐在食品工业,尤其是在肉制品加工工业中具有抑菌、抗氧化、赋予肉制品特殊风味及发色等重要作用。然而,亚硝酸盐的摄入超出正常范围会造成身体组织的氧气不足,还可形成亚硝胺,最终引发癌症,但目前还未发现单一物质可替代亚硝酸盐。可见,有效控制肉制品中亚硝酸盐含量具有极其重要的意义。文章探讨了亚硝酸盐对食品安全的影响,通过对从蔬菜、水果等中提取的具有亚硝酸盐清除作用的天然物质及其在肉制品中的应用进行概述,为具有亚硝酸盐清除作用的物质在降低肉制品中亚硝酸盐含量的研究提供了理论借鉴。 展开更多
关键词 肉制品 亚硝酸盐 清除剂 食品安全
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The utilization of spent palm cooking oil for formulating oil-based drilling muds with excellent H_(2)S scavenging capability
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作者 Sagheer A.Onaizi 《Petroleum Research》 EI 2024年第2期280-288,共9页
In this study,a spent palm cooking oil-based mud with an excellent H_(2)S scavenging capability induced by the inclusion of a small quantity of potassium permanganate is formulated and tested for the first time.The mu... In this study,a spent palm cooking oil-based mud with an excellent H_(2)S scavenging capability induced by the inclusion of a small quantity of potassium permanganate is formulated and tested for the first time.The mud formulation,containing the spent palm oil as the continuous phase and water as the dispersed phase,respectively,was stabilized by Span 80 and rhamnolipid biosurfactant as primary and secondary emulsifiers,respectively,while hydrophobic zinc nanoparticles(NPs)were used as weighting agent.The results showed that H_(2)S scavenging capacity at the breakthrough time reached 182.4 g H_(2)S/barrel mud,which increased to 417.9 g H_(2)S/barrel mud at the saturation time,demonstrating the effective H_(2)S scavenging performance of the formulated mud.The spent palm oil-based mud(SPOBM)also showed a good flow behavior that could be well fitted using the Herschel-Bulkley and Casson models.The effect of temperature on the apparent viscosity of the SPOBM has been investigated,and the fitting of the viscosity-temperature data provided an estimate of the activation energy as 23.53 kJ/mol.The findings reported in this article reveal the feasibility of transforming the spent/waste cooking oils into a valuable commodity for formulating greener drilling fluids with acceptable rheology and excellent H_(2)S scavenging performance. 展开更多
关键词 Hydrogen sulfide(H_(2)S) Oil-based mud(OBM)drilling fluids Spent palm oil H_(2)S scavengers Rheology
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基于红外相机研究脊椎动物在唐家河国家级自然保护区动物尸体分解过程中的作用 被引量:4
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作者 刁鲲鹏 李明富 +3 位作者 潘世玥 顾伟龙 张晓鸥 闻丞 《四川动物》 北大核心 2017年第6期616-623,共8页
通过在唐家河国家级自然保护区内自然死亡的8具动物尸体周围布设红外相机,详细记录了动物尸体在保护良好的自然条件下的分解过程。研究发现,除微生物与无脊椎动物外,脊椎动物在尸体分解过程中也起到很重要的作用:(1)动物尸体会吸引多种... 通过在唐家河国家级自然保护区内自然死亡的8具动物尸体周围布设红外相机,详细记录了动物尸体在保护良好的自然条件下的分解过程。研究发现,除微生物与无脊椎动物外,脊椎动物在尸体分解过程中也起到很重要的作用:(1)动物尸体会吸引多种脊椎动物前来取食,不同脊椎动物对尸体的利用方式和利用程度不一样。其中利用强度最高的动物为野猪Sus scrofa、亚洲黑熊Ursus thibetanus和大嘴乌鸦Corvus macrorhynchhos,实际贡献率分别为:87.15%、9.08%、3.72%,占所有脊椎动物对尸体取食强度的99.9%,其他动物贡献0.1%,如果子狸Paguma larvata、啮齿动物。(2)野猪有同类相食和拖动尸体的行为;绿背山雀Parus monticolus有采集尸体毛发筑巢的行为;未发现灵长类动物在尸体旁长时间逗留。根据研究结果,建议保护区在不污染水源的情况下,让自然死亡的尸体自然分解而不作深埋处理。 展开更多
关键词 尸体分解 食腐动物 唐家河国家级自然保护区 红外相机
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Ethylene control in fruit quality assurance:A material science perspective
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作者 Yi Jiang Zhanpeng Liu +3 位作者 Mohammad Peydayesh Bin Zhang Xiangze Jia Qiang Huang 《Aggregate》 EI CAS 2024年第5期86-108,共23页
The waste of resources associated with fruit decay is rapidly spreading globally,threatening the interests of relevant practitioners and the health of consumer groups,and demanding precise solutions.Controlling fruit ... The waste of resources associated with fruit decay is rapidly spreading globally,threatening the interests of relevant practitioners and the health of consumer groups,and demanding precise solutions.Controlling fruit ripening through ethylene reg-ulation is one of the most important strategies for providing high-quality fruits.However,current materials for ethylene regulation still have difficulty realizing their application potential due to high manufacturing costs and performance defi-ciencies.In this review,the ethylene-controlled release materials for ripening based on molecular encapsulation and the ethylene scavengers for preservation based on mechanisms such as oxidation,photodegradation,and adsorption are presented.We discuss and analyze a wide range of materials in terms of mechanism,perfor-mance,potential of applicability,and sustainability.The ethylene release behavior of encapsulating materials depends on the form in which the ethylene binds to the material as well as on environmental factors(humidity and temperature).For ethy-lene scavengers,there are a variety of scavenging mechanisms,but they generally require porous materials as adsorption carriers.We highlight the great opportunity of designing soft crystalline porous materials as efficient ethylene adsorbent due to their unique structural properties.We present this review,including a summary of practical characteristics and deficiencies of various materials,to establish a system-atic understanding of fruit quality assurance materials applied to ethylene regulation,anticipating a promising prospect for these new materials. 展开更多
关键词 crystalline porous materials ethylene scavengers fruit ripening control gas adsorption gas encapsulation
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藏北高原的“清道夫”——生态人类学视角下的西藏牛粪文化 被引量:4
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作者 皇甫睿 《广西民族研究》 CSSCI 北大核心 2021年第3期87-94,共8页
在千百年的游牧生活中,牛粪作为藏民非常重要的资源,已深深融入藏族文化,并形成了具有民族烙印的西藏牛粪文化。藏民对牛粪的利用方式多种多样,其中最重要、也最广泛的方式是作为燃料使用。由于外来文化的冲击,牛粪作为燃料的地位开始... 在千百年的游牧生活中,牛粪作为藏民非常重要的资源,已深深融入藏族文化,并形成了具有民族烙印的西藏牛粪文化。藏民对牛粪的利用方式多种多样,其中最重要、也最广泛的方式是作为燃料使用。由于外来文化的冲击,牛粪作为燃料的地位开始面临危机。人们在一定程度上否定了传统文化的某些重要组成部分,认为牛粪是重要的肥料资源,将其作为燃料使用是对草场资源的破坏与浪费。但是,如果从生态人类学的视角来审视藏民与牛粪利用之间的内在关联,就不难发现藏民对牛粪的利用方式实为对草场资源维护的重要手段。特别是藏民们在藏北高原特殊的生态环境下,在不断与当地生态系统的适应互动中,形成了一个相对独立、稳定运行的"文化生态共同体"。在该共同体运行的过程中,藏民们将牛粪作为燃料使用的行为,扮演着藏北高原生态系统中"清道夫"的角色。 展开更多
关键词 藏北高原 “清道夫” 生态人类学 西藏牛粪文化
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Evaluation of Reactive Oxygen Species (ROS) Generated on the Surface of Copper Using Chemiluminesence
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作者 Ken Hirota Hiroya Tanaka +4 位作者 Taika Maeda Kazuhiko Tsukagoshi Hiroshi Kawakami Takashi Ozawa Masahiko Wada 《Materials Sciences and Applications》 2023年第10期482-499,共18页
The antibacterial activity of copper is well-known from an ancient civilization, however, its biocidal mechanism has not been necessarily elucidated. Notwithstanding up to now, mainly 4 processes have been proposed. A... The antibacterial activity of copper is well-known from an ancient civilization, however, its biocidal mechanism has not been necessarily elucidated. Notwithstanding up to now, mainly 4 processes have been proposed. Among them, it is cleared that 4 kinds of reactive oxygen species (ROS): hydroxyl radical ·OH, hydrogen per oxide H<sub>2</sub>O<sub>2</sub>, superoxide anion ·O<sup>-</sup>2</sub></sub>   and singlet oxygen <sup>1</sup>O<sub>2</sub>, play an important role for contact-killing of bacteria, viruses and fungi. In this paper, generation of ROS on the surfaces of copper plates heated from room temperature to 673 K for 4.2 × 10<sup>2</sup> s in air, was investigated using the chemiluminescence. ROS have been evaluated by selecting the most suitable scavengers, such as 2-propanol for ·OH, sodium pyruvate for H<sub>2</sub>O<sub>2</sub>, nitro blue tetrazolium for ·O<sup>-</sup>2</sub></sub>,  and sodium azide NaN<sub>3</sub> for <sup>1</sup>O<sub>2</sub>. At the same time the outermost surface of copper, on which thin film of cuprous oxide Cu<sub>2</sub>O was first formed and then cupric oxide CuO was laminated on Cu<sub>2</sub>O, was examined by thin-film XRD and TEM analysis to estimate the amounts and kinds of copper oxides. It was found that the most amounts of ROS were obtained for the 573 K-heated Cu plate and they were composed of ·OH, H<sub>2</sub>O<sub>2</sub>, and ·O<sup>-</sup>2.</sub></sub>. 展开更多
关键词 COPPER Microbial Activity Reactive Oxygen Species CHEMILUMINESCENCE scavengers
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Edaravone Enhances the Viability of Ischemia/reperfusion Flaps 被引量:1
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作者 张栋益 康深松 +1 位作者 张正文 吴蕊 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第1期51-56,共6页
The purpose of the experiment was to study the efficacy of edaravone in enhancing flap viability after ischemia/reperfusion(IR) and its mechanism. Forty-eight adult male SD rats were randomly divided into 3 groups:... The purpose of the experiment was to study the efficacy of edaravone in enhancing flap viability after ischemia/reperfusion(IR) and its mechanism. Forty-eight adult male SD rats were randomly divided into 3 groups: control group(n=16), IR group(n=16), and edaravone-treated IR group(n=16). An island flap at left lower abdomen(6.0 cm×3.0 cm in size), fed by the superficial epigastric artery and vein, was created in each rat of all the three groups. The arterial blood flow of flaps in IR group and edaravone-treated IR group was blocked for 10 h, and then the blood perfusion was restored. From 15 min before reperfusion, rats in the edaravone-treated IR group were intraperitoneally injected with edaravone(10 mg/kg), once every 12 h, for 3 days. Rats in the IR group and control group were intraperitoneally injected with saline, with the same method and frequency as the rats in the edaravone-treated IR group. In IR group and edaravone-treated IR group, samples of flaps were harvested after reperfusion of the flaps for 24 h. In the control group, samples of flaps were harvested 34 h after creation of the flaps. The content of malondialdehyde(MDA) and activity of superoxide dismutase(SOD) were determined, and changes in organizational structure and infiltration of inflammatory cells were observed by hematoxylin-eosin(HE) staining, apoptotic cells of vascular wall were marked by terminal deoxynucleotidyl transferase-mediated d UTP nick-end labeling(TUNEL) assay, and the apoptotic rate of cells in vascular wall was calculated. The ultrastructural changes of vascular endothelial cells were observed by transmission electron microscopy(TEM). Seven days after the operation, we calculated the flap viability of each group, and marked vessels of flaps by immunohistochemical staining for calculating the average number of subcutaneous vessels. The results showed that the content of MDA, the number of multicore inflammatory cells and apoptotic rate of cells in vascular wall in the edarav 展开更多
关键词 free radical scavengers edaravone ischemia/reperfusion injury skin flap
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Phytochemical Analysis of Medicinal Plants with Kidney Protective Activities 被引量:1
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作者 Eric Jung-chi Lien Linda Lin-min Lien +1 位作者 Rubin Wang Jeffrey Wang 《Chinese Journal of Integrative Medicine》 SCIE CAS 2012年第10期790-800,共11页
In view of the increasing number of patients undergoing kidney dialysis or transplant every year, a survey of the literature on renal protective medicinal plants was undertaken. Most of them are from traditional Chine... In view of the increasing number of patients undergoing kidney dialysis or transplant every year, a survey of the literature on renal protective medicinal plants was undertaken. Most of them are from traditional Chinese medicine (TCM). Although many of the medicinal herbs reported have not been investigated in terms of active chemical ingredients, some do have compounds well characterized. They fall into a wide range of structures. Several groups of compounds with well established activities are discussed. These include: antioxidant phenolic compounds like tannins, flavonoids, isoflavonoids, unsaturated organic acids and lignans; circulation enhancing compounds like saponins, and basic alkaloids with multiple targets (G-protein coupled receptors). Also presented are proinflammatory and antiinflammatory fatty acids like linoleic (n-6) and α-Iinolenic (n-3) acids, respectively. Attention is also drawn to the plants containing nephrotoxic aristolochic acid. Different directions of future research are also presented. We hope that this review may provide some leads for new drug discovery and development, and more rational application of TCM. 展开更多
关键词 kidney protective herbs kidney protection natural products ANTIOXIDANTS free radical scavengers immunomodulating agents antiinflammatory agents structure-activity relationship physicochemical parameters
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