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Free radicals trigger the closure of open pores in lignin-derived hard carbons toward improved sodium-storage capacity 被引量:1
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作者 Wen-Jun Ji Zong-Lin Yi +8 位作者 Ming-Xin Song Xiao-Qian Guo Yi-Lin Wang Yi-Xuan Mao Fang-Yuan Su Jing-Peng Chen Xian-Xian Wei Li-Jing Xie Cheng-Meng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期551-559,共9页
The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium storage.However,the formation mechanism of closed pores under the influence of pore-forming ag... The chemical activation of various precursors is effective for creating additional closed pores in hard carbons for sodium storage.However,the formation mechanism of closed pores under the influence of pore-forming agents is not well understood.Herein,an effective chemical activation followed by a high-temperature self-healing strategy is employed to generate interconnected closed pores in lignin-derived hard carbon(HCs).By systematic experimental design combined with electron paramagnetic res-onance spectroscopy,it can be found that the content of free radicals in the carbon matrix influences the closure of open pores at high temperatures.Excessively high activation temperature(>700 C)leads to a low free radical concentration,making it difficult to achieve self-healing of open pores at high tempera-tures.By activation at 700°C,a balance between pore making and self-healing is achieved in the final hard carbon.A large number of free radicals triggers rapid growth and aggregation of carbon microcrys-tals,blocking pre-formed open micropores and creating additional interconnected closed pores in as-obtained hard carbons.As a result,the optimized carbon anode(LK-700-1300)delivers a high reversible capacity of 330.8 mA h g^(-1) at 0.03 A g^(-1),which is an increase of 86 mA h g^(-1) compared to the pristine lignin-derived carbon anode(L-700-1300),and exhibits a good rate performance(202.1 mA h g^(-1) at 1 A g^(-1)).This work provides a universal and effective guidance for tuning closed pores of hard carbons from otherprecursors. 展开更多
关键词 Hard carbon Chemical activation free radical SELF-HEALING Closed pores Sodium ion batteries
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Characteristics and fate behavior of environmentally persistent free radicals in atmospheric particulate matter
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作者 WANG Xueying CUI Long +2 位作者 XUE Yonggang HO Kinfai HUANG Yu 《地球环境学报》 CSCD 2024年第4期596-611,共16页
Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ... Background,aim,and scope Environmentally persistent free radicals(EPFRs)have received significant attention due to their longer lifetime and stable existence in various environments.The strong environmental migration ability of particulate matter allows EPFRs to migrate over long-distance transport,thereby impacting the quality of the local atmospheric environment.Additionally,EPFRs can also adhere to atmospheric particles and interact with typical gaseous pollutants to affect atmospheric chemical reactions.EPFRs can produce some reactive organic species,promoting oxidative stress in the human body,damaging biological macromolecules and ultimately affecting the organism health.EPFRs are considered as a novel type of pollutant that affects human health.Despite their significance,there are few literatures available on the characteristics and fate behaviors of EPFRs up to date.Therefore,supplemental reviews are crucial for providing comprehensive understanding of EPFRs.Materials and methods This review summarizes the characteristics of EPFRs in particulate matter,outlines the generation mechanism and influencing factors of EPFRs,and the impacts of EPFRs on environmental quality and organism health.Results The content of EPFRs in particulate matter ranges from 1017 to 1020 spins∙g−1.Due to the strong mobility of atmospheric particulate matter,the long-term exposure to high levels of EPFRs may aggravate the impact of particulate matter on human health.The interaction between EPFRs and typical gaseous pollutants can alter their fate and influence atmospheric chemical reactions.EPFRs are mainly produced by transition metal elements and substituted aromatic hydrocarbons through electron transfer.Additionally,the chemical bond rupture of organic substances through heat treatment or ultraviolet radiation can also produce EPFRs,and heterogeneous reactions are capable producing them as well.The production of EPFRs is not only influenced by transition metal elements and precursors,but also by various environmental factors such as oxygen,temperature,light radiation,and relative humidity.Discussion EPFRs in atmospheric particulates matters are usually rich in fine particulates with obvious seasonal and regional variations.They can easily enter the human respiratory tract and lungs with inhalable particulates,thereby increasing the risk of exposure.Additionally,EPFRs in atmospheric particulates can interact with some typical gaseous pollutants,impacting the life and fate of EPFRs in the atmosphere,and alter atmospheric chemical reactions.Traditionally,EPFRs are generated by transition metal elements and substituted aromatic hydrocarbons undergoing electron transfer in the post-flame and cool-zone regions of combustion systems and other thermal processes to remove HCl,H_(2)O or CO groups,ultimately produce semiquinones,phenoxyls,and cyclopentadienyls.Recent studies have indicated that EPFRs can also be generated under the conditions of without transition metal elemental.Organics can also produce EPFRs through chemical bond rupture during heat treatment or light radiation conditions,as well as through some heterogeneous reactions and photochemical secondary generation of EPFRs.The presence or absence of oxygen has different effects on the type and yield of EPFRs.The concentration,type,and crystal type of transition metal elements will affect the type,content,and atmospheric lifetime of EPFRs.It is generally believed that the impact of transition metal element types on EPFRs is related to the oxidation-reduction potential.The combustion temperature or heat treatment process significantly affects the type and amount of EPFRs.Factors such as precursor loading content,pH conditions,light radiation and relative humidity also influence the generation of EPFRs.EPFRs can interact with pollutants in the environment during their migration and transformation process in environmental medium.This process accelerates the degradation of pollutants and plays a crucial role in the migration and transformation of organic pollutants in environmental media.The reaction process of EPFRs may lead to the production of reactive oxygen species(ROS)such as∙OH,which can induce oxidative stress,inflammation and immune response to biological lung cells and tissues,leading to chronic respiratory and cardiopulmonary dysfunction,cardiovascular damage and neurotoxic effects,ultimately impacting the health of organisms.Conclusions The interaction mechanism between EPFRs in particulate matter and gaseous pollutants remains unclear.Furthermore,research on the generation mechanism of EPFRs without the participation of transition metals is not comprehensive,and the detection of EPFRs is limited to simple qualitative categories and lack accurate qualitative analysis.Recommendations and perspectives Further research should be conducted on the generation mechanism,measurement techniques,migration pathways,and transformation process of EPFRs.It is also important to explore the interaction between EPFRs in atmospheric particulate matter and typical gaseous pollutants. 展开更多
关键词 particulate matter(PM) environmentally persistent free radicals(EPFRs) formation mechanism influencing factors
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Decontamination of Cr(Ⅵ) from water using sewage sludge-derived biochar: Role of environmentally persistent free radicals 被引量:2
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作者 Yuhan Zhu Jia Wei Jun Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第4期97-103,共7页
Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced i... Biochar is a well-known material for pollutant removal owing to its low cost and rich surface functionality. A kind of highly active substance, called environmentally persistent free radicals(EPFRs), can be produced in the preparation process of biochar, playing an important role in the removal of pollutants.In this study, sludge-derived biochars(SBC_(120) and SBC_(270)) were prepared by the hydrothermal carbonization under two temperatures(120℃ and 270℃) to investigate their removal abilities of Cr(Ⅵ). The maximum removal amounts of Cr(Ⅵ) by SBC_(120) and SBC_(270) were 16.58 and 22.93 mg·g^(-1), respectively. It was further revealed that the appearance of Cr(Ⅲ), as a result of EPFRs on sludge-derived biochar(SBC) transferred electrons to Cr(Ⅵ) in neutral solutions. That is to say, oxygen-centered(O-centered) EPFRs on SBC_(120) and carbon-centered(C-centered) EPFRs on SBC_(270) all could be used as electron donors to Cr(Ⅵ) to make it become Cr(Ⅲ). This study not only provides a theoretical basis for the mechanism of pollutants removal by sludge-derived biochar but also offers a new perspective on the direct effect of EPFRs on pollutants. 展开更多
关键词 Sludge-derived biochar Environmentally persistent free radicals Chromium Removal Reduction
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Correlation of free radical level and apoptosis after intracerebral hemorrhage in rats 被引量:6
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作者 韩宁 丁素菊 +1 位作者 吴涛 朱幼丽 《Neuroscience Bulletin》 SCIE CAS CSCD 2008年第6期351-358,共8页
Objective To investigate the correlation of perihematomal free radical level and neuronal apoptosis following the intracerebral hemorrhage (ICH). Methods Animals were randomly divided into 4 groups: sham operation ... Objective To investigate the correlation of perihematomal free radical level and neuronal apoptosis following the intracerebral hemorrhage (ICH). Methods Animals were randomly divided into 4 groups: sham operation group, model group, 1 mg/kg edaravone group, and 3 mg/kg edaravone group. Each group was then divided into seven subgroups, in which the rats were correspondingly killed at 6 h, 12 h, 24 h, 48 h, 72 h, 7 d or 14 d (n = 1 in each subgroup of the sham group, and n = 6 in each subgroup of the other 3 groups). By Horseley-Clarke technique, autoblood (80 μL) were administered into the left caudate putamen of SD rats in a double administration-withdrawal way. Rats in the sham group were needled in but not administered with autoblood. The ICH model was then evaluated by Bederson's scale. Around the hematoma, the levels of malonaldehyde (MDA) and hydroxyl radical were tested by spectrophotometer, and the process of apoptosis was tested by terminal deoxynucleofidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) method. Results (1) ICH significantly increased the levels of MDA and hydroxyl radicals. Significant differences in MDA and hydroxyl radical contents were observed among the four groups. (2) In the sham group, a small number of TUNEL-positive cells were found. In the other three groups, the TUNEL-positive cells were observed at 6 h, increased significantly at 24 h, and reached peak level at 3 d, then fell profoundly at 7 d, but remained detectable at 14 d. (3) The positive correlation existed between apoptosis and free radical level (r = 0.2003), and existed between apoptosis and MDA content (r = 0.6563) in the brain. Conclusion Post-hemorrhagic apoptosis was related to the production of free radicals, indicating that the elevated free radicals following the ICH could induce neuron and glial cell apoptosis. 展开更多
关键词 intracerebral hemorrhage free radical APOPTOSIS TUNEL EDARAVONE
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Extraction Storage and Qualitative Analysis of Free Radicals Scavenging Substances from Sweet Potato Leaves 被引量:9
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作者 王友升 董银卯 +1 位作者 宋彦 黑维俭 《Agricultural Science & Technology》 CAS 2008年第2期1-5,9,共6页
[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging sub... [ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical. 展开更多
关键词 Sweet potato leaves free radicals scavenging Total phenol Total flavones
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Effects of Water─soluble Components Isolated from Salviamilltiorrhiza on Oxygen Free Radical Generation and LipidPeroxidation 被引量:10
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作者 李定友 徐理纳 刘小光 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第2期107-112,共6页
The effects of water─soluble components isolated from Salvia miltiorrhiza on oxygen free radical prodction and lipid peroxidation were estimated. Five components(10 μmol/L)were shown to inhibit superoxide anion gen... The effects of water─soluble components isolated from Salvia miltiorrhiza on oxygen free radical prodction and lipid peroxidation were estimated. Five components(10 μmol/L)were shown to inhibit superoxide anion generation by xanthine─xanthine oxidase system. It was also demonstrated that six components( 100 μmol/L) prevented H_2O_2─induced hemolysis and MDA fonnation in mouse erythrocytes.The effects of Sal A, Sal B, Sal C and Ros A were dose dependent. In Langendorff rat heart, pretreatment with Sal A 20μmol/L significantly prevented MDA production induced by 30 min reoxygenation after 45 min anoxia.The results indicated that there were also other potent antioxidant componentts in Salvia milliorrhiza besides Dphl and Pal. The protection of Sal A against myocardial anoxiareoxygenation inury may be mainly ascribed to its oxygen free radical scavenging activity. 展开更多
关键词 Salvia miltiorrhiza Salvianolic acid A Myocardial anoxiareoxygenation free radicals Lipid peroxide
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Oxidative Stress and Free Radical Damage in Patients With Acute Dipterex Poisoning 被引量:15
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作者 JUN-FuZHOU WENZHOU +2 位作者 SHU-MEIZHANG YAN-ERLUO HUAI-HONGCHEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第2期223-233,共11页
Objective To investigate whether acute dipterex poisoning (ADP) may cause oxidative stress and free radical damage in the bodies of acute dipterex poisoning patients (ADPPs), and to explore the mechanisms by which ADP... Objective To investigate whether acute dipterex poisoning (ADP) may cause oxidative stress and free radical damage in the bodies of acute dipterex poisoning patients (ADPPs), and to explore the mechanisms by which ADP may cause oxidative stress and free radical damage. Methods Fifty ADPPs and fifty healthy adult volunteers (HAVs) whose ages, gender and others were matched with the ADPPs were enrolled in a randomized controlled study, in which concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE) and P-carotene (P-CAR) in plasma as well as concentration of lipoperoxide (LPO), and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and acetylcholinesterase (AChE) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with the average values of experimental parameters in the HAVs group, the average values of plasma NO and erythrocyte LPO in the ADPPs group were significantly increased (P<0.0001), while those of plasma VC, VE and P-CAR as well as erythrocyte SOD, CAT, GPX and AChE in the ADPPs group were significantly decreased (P<0.0001). Bivariate correlation analysis and partial correlation analysis suggested that when NO and LPO values were increased, and VC, VE, β-CAR, SOD, CAT and GPX values were decreased in the ADPPs, AChE value was decreased gradually in the ADPPs (P<0.001-0.0001). Reliability analysis of experimental parameters reflecting oxidative stress and free radical damage in the ADPPs showed that the reliability coefficient (8 items) alpha=0.6909, and the standardized item alpha=0.8574. Conclusion The findings in the present study suggest that ADP can cause oxidative stress and free radical damage, and inhibit markedly erythrocyte acetylcholinesterase activity in ADPPs. 展开更多
关键词 Dipterex Dipterex poisoning Oxidative stress free radical damage free radicals Oxidation LIPOPEROXIDATION ACETYLCHOLINESTERASE
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May Chronic Childhood Constipation Cause Oxidative Stress and Potential Free Radical Damage to Children? 被引量:4
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作者 JI-YUEWANG YE-LINGWANG +1 位作者 SHENG-LIZHOU JUN-FUZHOU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第3期266-272,共7页
Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress an... Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress and potential free radical damage to chronic constipation patients (CCPs). Methods Sixty CCPs and sixty healthy child volunteers (HCVs) whose ages, gender and others were matched for the CCPs were enrolled in a randomized controlled study, in which levels of vitamin C (VC) and vitamin E (VE) in plasma as well as activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with average values of the above biochemical parameters in the HCVs group, the average values of VC and VE in plasma as well as those of SOD and CAT in erythrocytes in the CCPs group were significantly decreased (P<0.0001). Linear regression and bivariate correlation analysis showed that with prolonged course of the CCPs, the levels of VC and VE in plasma as well as the activities of SOD and CAT in erythrocytes in the CCPs were decreased gradually (P<0.0001). Conclusion The findings in the present study suggest that chronic childhood constipation causes oxidative stress and potential free radical damage to children with chronic constipation. 展开更多
关键词 Chronic childhood constipation Oxidative stress free radicals free radical damage Antioxidant Antioxidase
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Abnormal Reactions of Free Radicals and Oxidative Damages in the Bodies of Patients With Chronic Glomerulonephritis 被引量:23
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作者 ZHOUJUN-FU CHENJIA-XI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第3期233-244,共12页
Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty ... Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty chronic glomerulonephritis patients (CGNP) and eighty healthy adult volunteers (HAV) were enrolled in a random control study, in which concentrations of nitric oxide (NO) in plasma, lipoperoxides (LPO) in plasma and in erythrocytes, and vitamin C (VC), vitamin E (VE) and beta-carotene (?CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined with spectrophotometric assays. Results Compared with the average values of the above biochemical parameters in the HAV group, the average values of NO in plasma, and LPO in plasma and erythrocytes in the CGNP group were significantly increased (P = 0.0001), while those of VC, VE and -CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CGNP group were significantly decreased (P = 0.0001). Pearson product-moment correlation analysis showed that with increase of the concentration of blood creatinine as well as prolongation of the course of disease in the CGNP, the concentrations of NO in plasma, and LPO in plasma and erythrocytes in the CGNP increased gradually, while the concentrations of VC, VE and ?CAR in plasma as well as the activities of SOD, CAT and GPX in erythrocytes in the CGNP decreased gradually (P = 0.002454 0.000001). The relative risk ratio (RR) of the above biochemical parameters reflecting oxidative damages in the bodies of CGNP ranged from 6.061 to 72.429. The reliability coefficient (alpha) that the above biochemical parameters were used to reflect the oxidative damages of the CGNP was 0.8137, standardized item alpha = 0.9728, Hotelling抯 T-Squared = 1135680.191, F = 53274.6478, P = 0.000001. Conclusions The findings in this study show that in the bodies of CGNP a series of free radical chain reactions result in severe pathological aggravation and induce oxidative damages in their bodies. Therefore, suitable dose of antioxidants should be supplemented to them so as to alleviate oxidative damages in their bodies. 展开更多
关键词 Chronic glomerulonephritis free radicals Oxidation LIPOPEROXIDATION Nitric oxide Lipoperoxides ANTIOXIDANT Antioxidase Oxidative stress Oxidative damage
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Relationship between Acute Organophosphorus Pesticide Poisoning and Damages Induced by Free Radicals 被引量:29
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作者 ZHOU JUN-FU XU GEN-BO FANG WEI-JUN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第2期177-186,共10页
关键词 Organophosphorus pesticide poisoning free radicals Lipoperoxides Nitric oxide ANTIOXIDANTS Antioxidases
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Effect of resveratrol on pancreatic oxygen free radicals in rats with severe acute pancreatitis 被引量:18
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作者 Zhen-Dong Li Qing-Yong Ma Chang-An Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第1期137-140,共4页
AIM: To investigate the therapeutic effects of resveratrol (RESV) as a free radical scavenger on experimental severe acute pancreatitis (SAP). METHODS: Seventy-two male Sprague-Dawley rats were divided randomly ... AIM: To investigate the therapeutic effects of resveratrol (RESV) as a free radical scavenger on experimental severe acute pancreatitis (SAP). METHODS: Seventy-two male Sprague-Dawley rats were divided randomly into sham operation group, SAP group, and resveratrol-treated group. Pancreatitis was induced by intraductal administration of 0.1 mL/kg 4% sodium taurocholate. RESV was given intravenously at a dose of 20 mg/kg body weight. All animals were killed at 3, 6, 12 h after induction of the model. Serum amylase, pancreatic superoxide dismutase (SOD), malondialdehyde (MDA), and myeloperoxidase (MPO) were determined. Pathologic changes of the pancreas were observed under optical microscope. RESULTS: The serum amylase, pancreatic MPO and the score of pathologic damage increased after the induction of pancreatitis, early (3, 6 h) SAP samples were characterized by decreased pancreatic SOD and increased pancreatic MDA. Resveratrol exhibited a protective effect against lipid peroxidation in cell membrane caused by oxygen free radicals in the early stage of SAP. This attenuation of the redox state impairment reduced cellular oxidative damage, as reflected by lower serum amylase, less severe pancreatic lesions, normal pancreatic MDA levels, as well as diminished neutrophil infiltration in pancreas. CONCLUSION: RESV may exert its therapeutic effect on SAP by lowering pancreatic oxidative free radicals and reducing pancreatic tissue infiltration of neutrophils. 展开更多
关键词 Severe acute pancreatitis RESVERATROL Oxygen free radical NEUTROPHIL
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Component Analysis and Free Radicals Scavenging Activity of Physalis alkekengi L. Polysaccharide 被引量:19
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作者 CHENG Ying-kun LI Lei MENG Zhao-kun HOU A-li WU Yu-jie TENG Li-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第2期167-170,共4页
A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed... A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed of rhamnose, xylose, arabinose, galactose, and glucose. Free radicals scavenging activity of PAP was studied through 3 free radicals scavenging tests. PAP exhibited high scavenging effects on OH and DPPH radicals, and both the scavenging rates were about 80%. The scavenging rate of O2^- radical was about 22%. 展开更多
关键词 PHYSALIS POLYSACCHARIDE Component analysis free radicals scavenging activity
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Changes of free radicals and digestive enzymes in saliva in cases with deficiency inspleen-yin syndrome 被引量:16
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作者 Muxin Wei Yanmin Wu Dezheng Chen Yuchun Gu 《The Journal of Biomedical Research》 CAS 2010年第3期250-255,共6页
Objective:To explore the nature of deficiency in spleen-yin syndrome,which could provide scientific theoretical support and practical guidance for clinical Traditional Chinese Medicine(TCM)syndrome differentiation ... Objective:To explore the nature of deficiency in spleen-yin syndrome,which could provide scientific theoretical support and practical guidance for clinical Traditional Chinese Medicine(TCM)syndrome differentiation based on biology,and had a strong clinical significance.Methods:Serum Cu and Zn were detected by atomic absorption spectrophotometer,serum vitamin E by high performance liquid chromatography,serum vitamin C by 2,4-Dinitrophenylhydrazine Colorimetry,total superoxide dismutase(SOD)and Cu and Zn- SOD by the xanthine oxidase method,and malondialdehyde(MDA)by the 2-thiobarbituric acid method(TBA).Total antioxidant capacity was detected by a colorimetry kit.Amylase Activity was detected by an automatic biochemical analyzer.Lysozyme was detected by lysozyme detection plate,the diameter of bacteriolysis circle was measured and the corresponding content of lysozyme was obtained from a table of standard curve values.Results: No significant difference in total SOD and Cu,Zn-SOD was found between deficiency in spleen-yin group and normal group.However,such factors in deficiency in kidney-yin group were significantly lower than the other groups(P〈0.05).The MDA content in both deficiency in spleen-yin group and deficiency in kidney-yin group were significantly higher than that of normal group(P〈0.05),while the total antioxidant capacity was significantly lower than normal group(P〈0.05).The vitamin E content in deficiency in kidney-yin group was significantly lower than that in the other two groups(P〈0.05).No significant difference in the contents of vitamin C,Cu and Zn were observed in these groups.The Zn/Cu level in deficiency in kidney-yin group and the vitamin E level in deficiency in spleen-yin group decreased,but with no significant difference.Amylase activity in unit time in cases with deficiency in spleen-yin was lower than and had significant differences with that in normal cases,and higher than that in cases with deficiency in kidney-yin.The sectional velocity of saliva and the ratio of lysozyme in normal case group were significantly higher than other two groups,while deficiency in the spleen-yin group was significantly higher than the deficiency in kidney-yin group.Conclusion:All the results indicated that the objective pathological mechanism between the deficiency in spleen-yin and deficiency in kidney-yin was different. 展开更多
关键词 deficiency in spleen-yin deficiency in kidney-yin digestive enzymes in saliva AMYLASE salivary lysozyme salivary flow rate free radicals
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Inhibitory effects of grape procyanidins on free radical-induced cell damage in rat hepatocytes in vitro 被引量:10
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作者 Jin-Yi Zhong Hong-Qun Cong Li-Hua Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第19期2752-2755,共4页
AIM: To study the protective effect of grape procyanidins on oxidative injury induced by ethanol and carbon tetrachloride in rat hepatocytes. METHODS: Normal rat hepatocytes as well as cells damaged by ethanol or ca... AIM: To study the protective effect of grape procyanidins on oxidative injury induced by ethanol and carbon tetrachloride in rat hepatocytes. METHODS: Normal rat hepatocytes as well as cells damaged by ethanol or carbon tetrachloride were incubated with different doses of grape procyanidins for 24 h. Cell proliferation, apoptosis and TNFα mRNA expression were subsequently determined using MTT assay, cell death ELISA and in situ hybridization. RESULTS: Proliferative levels of the control cells from ethanol and CCh injury groups significantly decreased while apoptosis and TNFα mRNA expression significantly increased compared to the normal control and grape procyanidins co-treatment groups (0.455 ± 0.051 vs 0.318 ±0.045, P 〈 0.05). In comparison with the normal control, 50 and 100 mg/L grape procyanidins significantly stimulated cell growth, with a better effect observed with 100 mg/L grape procyanidins. CONCLUSION: Grape procyanidins inhibit the hepatocyte damage induced by ethanol and carbon tetrachloride, and stimulate normal hepatocyte proliferation. 展开更多
关键词 Grape procyanidin free radical Cell proliferation Apoptosis HEPATOCYTE
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Effects of total soy saponins on free radicals in the quadriceps femoris,serum testosterone,LDH,and BUN of exhausted rats 被引量:8
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作者 Zhigang Liu Ruixin Nie +3 位作者 Yun Liu Zhouhong Li Chenxi Yang Zhengying Xiong 《Journal of Sport and Health Science》 SCIE 2017年第3期359-364,共6页
Purpose:The aim of this study was to investigate the impact of total soy saponins(TS) on the free radical metabolism from the quadriceps femoris muscle,serum testosterone,lactate dehydrogenase(LDH),and blood urea nitr... Purpose:The aim of this study was to investigate the impact of total soy saponins(TS) on the free radical metabolism from the quadriceps femoris muscle,serum testosterone,lactate dehydrogenase(LDH),and blood urea nitrogen(BUN) in rats exercised to exhaustion.Methods:A one-time exhausted treadmill exercise session was used.Sprague-Dawley rats were divided into 4 groups:a control group—animals receiving no TS and no exercise(NTSNE),animals receiving TS but no exercise group(TSNE),animals receiving no TS but exercised to exhaustion group(NTSE),and animals receiving TS and exercised to exhaustion group(TSE).The TSNE and TSE groups were fed TS at a dosage of 20 mg/kg body weight once per day for 2 weeks.The NTSE group was given a placebo,and the NTSNE group was not given any treatment.The NTSE and TSE groups were exercised at speed of 30 m/min on treadmill until exhausted.The exercise time and exercise distance were recorded when the rats became exhausted and the rats were then decapitated and anatomized immediately.A 10% homogenate of the quadriceps femoris tissue was prepared.The levels of superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA),glutathione peroxidase(GSH-Px),glutathione reductase(GR),reduced glutathione(GSH),total antioxidant capacity(T-AOC),LDH,BUN,and serum testosterone were tested.Results:TS significantly increased the exercise time to exhaustion by 20.62%(p < 0.05).The MDA levels were decreased significantly in the TSNE group than in NTSNE group(p < 0.05);the T-AOC levels increased significantly in the TSNE group than in the other 3 groups(p < 0.01,p < 0.05,p < 0.05).The LDH activity significantly increased in the NTSE group than in TSNE group(p < 0.05).The BUN levels significantly increased in the NTSE group than in the other 3 groups(p < 0.01,p < 0.01,p < 0.05),and significantly increased in the TSE group than in NTSNE and TSNE groups(both p < 0.01).The serum testosterone levels increased significantly in the TSNE group than in the other 3 groups(all p < 0.01).SOD,CAT,GSH-Px,GR,and GSH were not statistically different among the groups.Conclusion:TS can significantly improve the exercised rats' serum testosterone level and antioxidant activity in their quadriceps femoris to varying degrees,decrease MDA and serum LDH and BUN levels,increase the exercise time,and delay the occurrence of the fatigue. 展开更多
关键词 Exercised rat free radical Quadriceps femoris Serum enzymes TESTOSTERONE Total soy saponins
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Oxidative stress and damage induced by abnormal free radical reactions and IgA nephropathy 被引量:4
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作者 陈佳兮 周君富 沈汉超 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第1期61-68,共8页
Objective: To estimate the oxidative stress and oxidative damage induced by abnormal free radical reactions in IgA nephropathy (IgAN) patients' bodies. Methods: Seventy-two IgA N patients (IgANP) and 72 healthy ad... Objective: To estimate the oxidative stress and oxidative damage induced by abnormal free radical reactions in IgA nephropathy (IgAN) patients' bodies. Methods: Seventy-two IgA N patients (IgANP) and 72 healthy adult volunteers (HAV) were enrolled in a random control study design, in which the levels of nitric oxide (NO) in plasma, lipoperoxide (LPO) in plasma and in erythrocytes, and vitamin C (VC), vitamin E (VE) and β-carotene (β-CAR) in plasma as well as the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined with spectrophotometric mothods. Results: Compared with the HAV group, the averages of NO in plasma, and LPO in plasma and in erythrocytes in the IgANP group were significantly increased (P<0.0001), while those ofVC, VE and β-CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the IgANP group were significantly decreased (P<0.0001). Linear correlation analysis showed that with the increase of the values of NO, and LPO in plasma and in erythrocytes, and with the decrease of those ofVC, VE, β-CAR,SOD, CAT and GPX in the IgAN patients, the degree of histological damage of tubulointerstitial regions was increased gradually (P<0.0001); and that with the prolongation of the duration of disease the values of NO, and LPO in plasma and erythrocytes were increased gradually, while those of VC, VE, β-CAR, SOD, CAT and GPX were decreased gradually (P<0.005). The discriminatory correct rates of the above biochemical parameters reflecting oxidative damage of the IgAN patients were 73.8%-92.5%, and the correct rates for the HAV were 70.0%-91.3% when independent discriminant analysis was used; and the correct rate for the IgAN patients was increased to 98.8%, the correct rate for the HAV was increased to 100% when stepwise discriminant analysis was used. The above biochemical parameters' reliability coefficient (alpha) were used to estimate the oxidative damage of the IgAN patients as 0.8145, the standardized item alpha=0.9730, F=53273.5681, P<0.0001. Conclusions: A series of free radical chain reactions caused serious pathological aggravation in the IgANP' bodies, thus resulting in oxidative damage in their bodies. In treating IgANP, therefore, it is necessary that suitable dose antioxidants should be supplemented to them so as to alleviate the oxidative damage in their bodies. 展开更多
关键词 Chronic glomerulonephritis free radicals OXIDATION LIPOPEROXIDATION Nitric oxide Lipoperoxide ANTIOXIDANT Antioxidase Oxidative stress Oxidative damage
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DESIGN AND SYNTHESIS OF NOVEL CHIRAL IONIC LIQUIDS AND THEIR APPLICATION IN FREE RADICAL POLYMERIZATION OF METHYL METHACRYLATE 被引量:5
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作者 宛新华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第3期265-270,共6页
Two new chiral ionic liquids, 1 -((-)-menthoxycarbonylmethylene)-3-methylimidazolium hexafluorophosphateand 1-((-)-menthoxycarbonylmethylene)-3-hexadecylimidazolium hexafluorophosphate, were designed an d prepared. Th... Two new chiral ionic liquids, 1 -((-)-menthoxycarbonylmethylene)-3-methylimidazolium hexafluorophosphateand 1-((-)-menthoxycarbonylmethylene)-3-hexadecylimidazolium hexafluorophosphate, were designed an d prepared. Theirchemical structures were characterized by ~1H-NMR. Reverse atom transfer radical polymerization of methyl methacrylate(MMA) in these two ionic liquids was carried out using AIBN/CuCl_2/bipy as the initiating system. The resultant well-definedpolymethyl methacrylate (PMMA) was employed as a macroinitiator to induce the atom transfer radical polymerization ofmenthyl methacrylate (MnMA) in chlorobenzene, which yielded a PMMA-b-PMnMA diblock copolymer with narrow polydispersity. 展开更多
关键词 Chiral ionic liquids Reverse ATRP free radical polymerization Methyl methacrylate Menthyl methacrylate
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Free Radical Generation by Selenium Compounds and Their Prooxidant Toxicity 被引量:11
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作者 JULIAN E. SPALLHOLZ(Food and Nutrition, Texas Technology University,Lubbock, TX 79404, USA) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1997年第2期260-270,共11页
Selemum (Se) and many of its compounds are among the most toxic of nutrients. Selenium toxicity was first described in range animals in the western United States in the 1930's which consumed' selenium accumula... Selemum (Se) and many of its compounds are among the most toxic of nutrients. Selenium toxicity was first described in range animals in the western United States in the 1930's which consumed' selenium accumulator' plants of the genus Astragalus, Xylorrhiza,Oonopsis, and Stanleya. Selenites and selenates from the soil accumulate in these plants primarily as methylated selenium compounds and plants evolve dimethyldiselenide and dimethyselenide.Dietary selenium, primarily as selenomethionine and selenocysteine for humans fulfill the dietary requirement for selenoenzymes and proteins. In humans and animals excessive dietary selenium may be toxic. In vitro, selenium compounds such as selenite, selenium dioxide and diselenides react with thiols, such as glutathione, producing superoxide and other reactive oxygen species. This catalytic reaction of selenium compounds with thiols likely accounts for selenium toxicity to cells ex vivo and in vivo where the major glutathione producing organ,the liver, is also the major target organ of selenium toxicity.Selenium enzymes and selenoethers that do not readily form a selenide (RSe-) anion and compounds such as Ebselen where selenium is sequestered, are not toxic. Methylation of selenium by both plants and animals serves to detoxify selenium by generating methylselenides. Alternatively, full reduction of Se to elemental selenium (Se0) as done by some bacteria and the formation of heavy metal selenides such as Ag2Se or Hg2Se, results in a non-catalytic nontoxic form of selenium.This catalytic prooxidant attribute of some selenium compounds appears to account for its toxicity when such activity exceeds plant and animal methylation reactions and antioxidant defenses. This prooxidant activity may also account for cellular apoptosis and may provide a useful pharmaceutical application for selenium compounds as antibacterial, antiviral, antifungal and anticancer agents 展开更多
关键词 free radical Generation by Selenium Compounds and Their Prooxidant Toxicity GSH
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Evaluation of free radical scavenging activity of various extracts of leaves from Kedrostis foetidissima(Jacq.)Cogn 被引量:7
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作者 Kalaisezhiyen Pavithra Sasikumar Vadivukkarasi 《Food Science and Human Wellness》 SCIE 2015年第1期42-46,共5页
The present study was aimed to investigate the in vitro free radical scavenging activity of various leaf extracts(aqueous,methanol,acetone chloroform and petroleum ether)of Kedrostis foetidissima.In vitro free radical... The present study was aimed to investigate the in vitro free radical scavenging activity of various leaf extracts(aqueous,methanol,acetone chloroform and petroleum ether)of Kedrostis foetidissima.In vitro free radical scavenging activities of the extracts were assessed against DPPH and hydroxyl radicals.The metal chelating activity and reducing power ability of the extracts were also determined.The free radical scavenging activity was found to be high in methanolic extract for DPPH and hydroxyl radicals in a concentration dependent manner followed by chloroform,aqueous,acetone and petroleum ether extracts.The metal chelating activity and reducing power ability was also found to be high in methanolic extract.The difference in scavenging potential of the extracts may be due to variation in the percentage of phytoconstituents extracted in various solvents.Thus the result suggests that the methanolic leaf extract of K.foetidissima could serve as a potential source of antioxidants and can be explored as a therapeutic agent in free radical induced diseases.©2015 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. 展开更多
关键词 free radicals Kedrostis foetidissima ANTIOXIDANTS PHENOLS Scavenging activity
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Effect of Diazepam on the Contents of Amino Acids and Free Radical during Ischemia/Reperfusion Injury 被引量:5
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作者 胡波 梅元武 +3 位作者 魏桂荣 邱小鹰 孙圣刚 童萼塘 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2001年第2期102-104,共3页
The protective effect and mechanism of diazepam on ischemia neurons during cerebral ischemia and reperfusion were studied. Sixty three Wistar rats were divided randomly into nine groups: control group , ischemia gro... The protective effect and mechanism of diazepam on ischemia neurons during cerebral ischemia and reperfusion were studied. Sixty three Wistar rats were divided randomly into nine groups: control group , ischemia groups including subgroups of is3h, is3 h/rep1 h, is3 h/rep2 h, is3 h/rep3 h, diazepam treated groups , including subgroups of is3 h, is3 h/rep1 h, is3 h/rep2 h, is3 h/rep3 h with Zea longa's animal model of middle cerebral artery occlusion. The comparison between the ischemia group and diazepam treated group showed that diazepam could obviously decrease the production of glutamate, asparate, MDA and increase the synthesis and release of GABA, SOD and GSH PX. It was concluded that diazepam exerted its protective effects on neurons through complex mechanisms of regulating the synthesis and release of excitotary/inhibitory amino acids and free radicals. 展开更多
关键词 DIAZEPAM excitatory/inhibitory amino acids free radicals
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