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Decontamination of Cr(Ⅵ) from water using sewage sludge-derived biochar: Role of environmentally persistent free radicals
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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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Changes of free radicals and digestive enzymes in saliva in cases with deficiency inspleen-yin syndrome 被引量:14
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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 bas... 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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Evaluation of free radical scavenging activity of various extracts of leaves from Kedrostis foetidissima(Jacq.)Cogn 被引量:6
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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 group... 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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Butein imparts free radical scavenging, anti-oxidative and proapoptotic properties in the flower extracts of Butea monosperma 被引量:2
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作者 ANURADHA SEHRAWAT VIJAY KUMAR 《BIOCELL》 SCIE 2012年第2期63-71,共9页
The flower of Butea monosperma(Lam.)(Fabaceae)has been used in traditional Indian medicine in the treatment of many ailments including liver disorders.To understand the pharmacological basis of its beneficial effects,... The flower of Butea monosperma(Lam.)(Fabaceae)has been used in traditional Indian medicine in the treatment of many ailments including liver disorders.To understand the pharmacological basis of its beneficial effects,the extracts of dried flowers in water,methanol,butanol,ethyl acetate and acetone were evaluated for free radical scavenging and pro-apoptotic activities in cell cultures(human hepatoma Huh-7 cell line and immortalized AML-12 mouse hepatocytes).Butrin and butein-the active constituents of flower extracts-were used as reference molecules.The levels of cell injury markers like lactate dehydrogenase,glutathione and lipid peroxidation and primary antioxidant enzymes glutathione S-transferase and catalase were also measured.The aqueous and butanolic extracts exhibited better 2,2-diphenyl-1-picrylhydrazyl scavenging and cytotoxic activities in hepatoma cells than in immortalized hepatocytes.Interestingly,butein inhibited 2,2-diphenyl-1-picrylhydrazyl radical better than butrin.The aqueous and butanolic extracts were further investigated for hepatoprotection against carbon tertrachloride-induced biochemical changes and cell death.Both extracts,just as butrin and butein,significantly reversed the cellular glutathione levels and lipid peroxidation,and glutathione–S-transferase activity.Lactate dehydrogenase leakage and cell death were also prevented.However,only butein revived the catalase activity.Thus,the butein content of Butea monosperma flower extracts is important for free radical scavenging activity,apoptotic cell death and protection against oxidative injury in hepatic cells. 展开更多
关键词 butrin CYTOTOXICITY HEPATOPROTECTION methanol extract free radical scavenging
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SYNTHESIS OF HETEROARM STAR-SHAPED POLYMER BY THE USE OF POLYFUNCTIONAL CHAIN-TRANSFER AGENT via CONVENTIONAL FREE RADICAL POLYMERIZATION 被引量:2
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作者 石艳 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第3期321-329,共9页
Heteroarm star-shaped polymers were synthesized by conventional free radical polymerization in two steps by the use of polyfunctional chain transfer agent.In the first step,free radical polymerization of methyl methac... Heteroarm star-shaped polymers were synthesized by conventional free radical polymerization in two steps by the use of polyfunctional chain transfer agent.In the first step,free radical polymerization of methyl methacrylate was carried out in the presence of a polyfunctional chain transfer agent,pentaerythritol tetrakis(3-mercaptopropinate).At appropriate monomer conversions,two-arm PMMA having two residual thiol groups at the chain center or three-arm PMMA having one residual thiol group at the core wer... 展开更多
关键词 Heteroarm star-shaped polymer Conventional free radical polymerization Polyfunctional chain-transfer agent
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Stereoselective Functionalization at C-2 and C-3 of the Gibberellin via an Intramolecular Free Radical Cyclization Approach 被引量:1
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作者 An Qi CHEN1*, Christine L. WILLIS2 1Department of Chemistry, Xiamen University, Xiamen, 361005 2School of Chemistry, University of Bristol, Bristol, UK BS8 1TS 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第5期397-398,共2页
Stereoselective functionalization at C-2 and C-3 of the gibberellin skeleton was achieved via an intramolecular free radical cyclization approach using a tethered C-19 halomethyl ester as the radical precursor.
关键词 GIBBERELLIN LACTONIZATION free radical cyclization.
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Effects of Chuanxiongqin hydrochloride on increasing the fluidity of brain cell membrane and scavenging free radicals in model rats with ischemia/reperfusion injury 被引量:1
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作者 Chenxu Li Institute of Brain Sciences Department of Physiology, Medical College, Datong University, Datong 037008, Shanxi Province, China 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第8期721-724,共4页
BACKGROUND: The fluidity of cell membrane can be affected by various factors. Many experiments have confirmed that the ischemia/reperfusion of organic tissue can increase the contents of free radicals, which lead to h... BACKGROUND: The fluidity of cell membrane can be affected by various factors. Many experiments have confirmed that the ischemia/reperfusion of organic tissue can increase the contents of free radicals, which lead to high rigidity and low fluidity of cell membrane, and the conditions can be changed by Chuanxiongqin. OBJECTIVE: To observe the effect and mechanism of Chuanxiongqin hydrochloride on the fluidity of brain cell membrane in rat models of ischemia/reperfusion. DESIGN: A completely randomized controlled animal trial. SETTINGS: Institute of Brain Sciences; Department of Physiology, Medical College, Datong University. MATERIALS: Twenty male grade Ⅰ Wistar rats of 170-220 g were randomly divided into model group (n =10) and control group (n =10). Chuanxiongqin hydrochloride (molecular mass was 172.2) was purchased from the National Institute for the Control of Pharmaceutical and Biological Products (batch number: 0817-9803); Spin labelers: 5-doxyl-stearlic acid methylester (5DS), 16-doxyl-stearlic acid methylester (16DS), xanthine, xanthine oxidase (XOD) and 5,5-dimeth-1-pyrroline- N-oxide (DMPO) from Sigma Company; Bruker ESP 300 electron paramagnetic resonance (EPR) spectrometer by Bruker Company (Germany). METHODS: The experiments were carried out in the State Key Laboratory of Natural and Biomimetic Drugs, Peking University from June 2001 to July 2002. In the model group, rats were made into models of cerebral ischemia by 30-minute ligation and 2-hour reperfusion of common carotid arteries; The rats in the control group were not made into models. The order parameter (S) and rotational correlation time (τc) were detected with the ESR spectrometer by means of spin labeling. The greater the S and τc, the smaller the fluidity. Meanwhile, the clearance rate of free radicals was detected with ESR spin trapping. The measurement data were compared using the t test. MAIN OUTCOME MEASURES: The S, τc and clearance rates of O2 · and OH· free radicals were compared between the model group and control group. RESULTS: The S and τc in the model group [0.738 4±0.003 5; (8.472±0.027)×10-10 s/circle] were obviously different from those in the control group [0.683 9±0.008 3; (7.945±0.082)×10-10 s/circle, t =5.731, 5.918, P < 0.05], which suggested that ischemia/reperfusion injury decreased the fluidity of brain cell membrane. After adding Chuanxiongqin hydrochloride, there were no obvious differences between the model group [0.688 5±0.030 5; (7.886±0.341)×10-10 s/circle] and control group (P > 0.05), indicating that Chuanxiongqin hydrochloride could recover the fluidity of brain cell membrane after ischemia/reperfusion injury close to the level in the normal control group. Chuanxiongqin hydrochloride could directly scavenge the O2 · and OH· free radicals, and the maximal clearance rates were 83.92% and 44.99% respectively. CONCLUSION: Chuanxiongqin hydrochloride increases the fluidity of membrane of ischemia-injured brain cell by scavenging both O2 ·and OH· free radicals. 展开更多
关键词 Effects of Chuanxiongqin hydrochloride on increasing the fluidity of brain cell membrane and scavenging free radicals in model rats with ischemia/reperfusion injury cell free
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Election Spin Resonance Studies of Free Radical Formation and Oxygen Consumption of Lens Epithelium During Ultraviolet Exposure 被引量:1
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作者 Jiemin Xu, CunpuSun, Ke Wu, Jianqiang Shao, Qing Shan, Jianbo Cong, Jianzhong Zhang~# Beijing Institute of Radiation Medicine, Beijing 100850, China~#Graduate School, Academia Sinica 《眼科学报》 1993年第1期15-18,共4页
A long life election spin resonance (ESR) signal at g=2.0006 was observed in the normal lens epithelium and cortical fibers. During ultraviolet (UV) exposure, a new ESR signal at g = 2.0060 was found in the lens epith... A long life election spin resonance (ESR) signal at g=2.0006 was observed in the normal lens epithelium and cortical fibers. During ultraviolet (UV) exposure, a new ESR signal at g = 2.0060 was found in the lens epithelium. But this specific signal was not detected in the lens cortical fibers. This suggested that lens epithelial cells were more susceptible to the free radical formation which was induced by UV light. By means of ESR spin probe oxymetry, the oxygen uptake of lens epithelial cells was meas... 展开更多
关键词 election spin resonance (ESR) lens epithelium free radical oxygen consumption ultraviolet (UV) exposure
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Why Static O-H Bond Parameters Cannot Characterize the Free Radical Scavenging Activity of Phenolic Antioxidants: ab initio Study
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作者 Hong Yu ZHANG1,2 *, You Min SUN2, De Zhan CHEN2 1Laboratory for Computational Biology, Zibo University, Zibo 255091 2Department of Chemistry, Shandong Teachers’ University, Jinan 250014 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第1期75-78,共4页
The static O-H bond parameters including O-H bond length, O-H charge difference, O-H Mulliken population and O-H bond stretching force constant (k) for 17 phenols were calculated by ab initio method HF/6-31G**. In com... The static O-H bond parameters including O-H bond length, O-H charge difference, O-H Mulliken population and O-H bond stretching force constant (k) for 17 phenols were calculated by ab initio method HF/6-31G**. In combination with the O-H bond dissociation enthalpies (BDE) of the phenols determined by experiment, it was found that there were poor correlationships between the static O-H bond parameters and O-H BDE. Considering the good correlationship between O-H BDE and logarithm of free radical scavenging rate constant for phenolic antioxidant, it is reasonable to believe that the ineffectiveness of static O-H bond parameters in characterizing antioxidant activity arises from the fact that they cannot measure the O-H BDE. 展开更多
关键词 ANTIOXIDANTS free radical scavenging effect O-H bond dissociation enthalpy O-H bond length O-H bond stretching force constant O-H charge difference O-H Mulliken population QSAR.
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Influence of rotating magnetic field on cerebral infarction volume, cerebral edema and free radicals metabolism after cerebral ischemia/reperfusion injury in rats
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作者 Xiaohong Liu1, Zhiqiang Zhang2, Lixin Zhang3 1Liaoning Disabled Children’s Rehabilitation Center, Shenyang 110015, Liaoning Province, China 2Department of Rehabilitation, Second Hospital Affiliated to China Medical University, Shenyang 110003, Liaoning Province, China 3Department of Rehabilitation and Physiotherapy, First Hospital Affiliated to China Medical University, Shenyang 110001, Liaoning Province, China 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第9期777-780,共4页
BACKGROUND: It has shown that magnetic field can improve blood circulation, decrease blood viscosity, inhibit free radicals, affect Ca2+ flow in nerve cells, control inflammatory and immunological reaction, and accele... BACKGROUND: It has shown that magnetic field can improve blood circulation, decrease blood viscosity, inhibit free radicals, affect Ca2+ flow in nerve cells, control inflammatory and immunological reaction, and accelerate nerve cell regeneration. In addition, protective effect of magnetic field, which acts as an iatrophysics, on ischemic brain tissues has been understood gradually. OBJECTIVE: To investigate the effects of rotating magnetic field (RMF) on volume of cerebral infarction, cerebral edema and metabolism of free radicals in rats after cerebral ischemia/reperfusion injury. DESIGN: Randomized controlled animal study. SETTING: Rehabilitation Center of disabled children, Liaoniang; Department of Rehabilitation, the Second Affiliated Hospital, China Medical University; Department of Rehabilitation Physiotherapy, the First Affiliated Hospital, China Medical University. MATERIALS: A total of 70 healthy Wistar rats aged 18-20 weeks of both genders were selected and randomly divided into 3 groups: sham operation group with 12 rats, control group with 20 rats and treatment group with 38 rats. The treatment group included 4 time points: immediate reperfusion with 6 ones, 6-hour reperfusion with 20 ones, 12-hour reperfusion with 6 ones and 18-hour reperfusion with 6 rats. Main instruments were detailed as follows: magnetic head of rotating magnetic device was 6 cm in diameter; magnetic induction intensity at the surface of magnetic head was 0.25 T in silence; the maximal magnetic induction intensity was 0.09 T at the phase of rotation; the average rotating speed was 2500 r per minute. METHODS: The experiment was carried out in the China Medical University in March 2003. Focal cerebral ischemic animal models were established with modified Longa's method. Operation was the same in the sham operation, but the thread was inserted as 10 mm. Neurologic impairment was assessed with 5-rating method to screen out cases. Those survivals with grade 1 and grade 2 after ischemia for 2 hours and reperfusion for 24 hours were included in the control group and treatment group. Those in the sham operation group and control group were not treated with RMF. Magnetic head was directed towards the head of rats of the treatment group, and the magnetic head was about 7 mm from skin, treated for 15 minutes. The rats were decapitated to take out brains at 24 hours after reperfusion in each group. Water content of brain and volume of cerebral infarction were assessed with wet-dry weight method and TTC staining, respectively. Activity of superoxide dismutase (SOD), content of malondialdehyde (MDA) and change of brain histomorphology in brain tissue of ischemic side were analyzed. MAIN OUTCOME MEASURES: ① Volume of cerebral infarction and changes of water content in brain; ② measurements of SOD and MDA contents in brain tissue of rats in all groups. RESULTS: A total of 70 qualified animals were involved in the final analysis after rejecting the death and unqualified animal models. ① Water content of brain: Water content of brain in the treatment was less than that in the control group at any time point except the immediate time point, and cerebral edema was relieved [(2.48±0.22)%, (2.32±0.19)%, (2.23±0.36)%, (2.91±0.44)%, P < 0.05]. In addition, there were no significant differences among 6-hour, 12-hour and 18-hour reperfusion groups (P > 0.05). ② Volume of cerebral infarction: The absolute volume of cerebral infarction in the treatment group was smaller than that in the control group [(128.21±15.05), (171.22±40.50) mm3, t =2.438, P < 0.05], and the relative volume of cerebral infarction was smaller than that in the control group [(20.22±1.44)%, (25.17±3.85)%, t =2.95, P < 0.05]. ③ Contents of SOD and MDA in brain tissues: Compared with the control group, the SOD content in the brain tissue in the treatment group increased [(54.54±3.85), (69.52±5.88) kNU/g, t =5.568, P < 0.05], while the MDA content decreased [(0.85±0.06), (1.03±0.09) μmol/g, t =4.076, P < 0.05]. ④ General morphological observation: General morphology manifested that the edema was distinct in the right cerebral hemisphere in the control group, showing fat-like white, shallow anfractuosity, flat gyria, brittle tissue and easy to break up. The edema of right cerebral hemisphere was light and surface was hyperaemia in the treatment group. CONCLUSION: RMF may improve anti-oxidative ability of brain tissue of rats with acute focal cerebral ischemia/reperfusion injury and reduce volume of cerebral infarction and degrees of cerebral edema. 展开更多
关键词 cerebral edema and free radicals metabolism after cerebral ischemia/reperfusion injury in rats free
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Entropy, Free Radical and Life System
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作者 Honghu Li Junhua Hou 《Open Journal of Biophysics》 2016年第4期83-89,共8页
Effects of entropy and free radical in life system are elucidated. The results indicate that living organism can maintain normal activities only if a suitable free radicals inside living organism can be guaranteed. Ex... Effects of entropy and free radical in life system are elucidated. The results indicate that living organism can maintain normal activities only if a suitable free radicals inside living organism can be guaranteed. Excessive free radical should be eliminated to reduce entropy in living organism. Some ways provided to eliminate excessive free radical, reduce entropy and keep health. 展开更多
关键词 ENTROPY free radical Living Organisms
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Quality aspects of coffees and teas: Application of electron paramagnetic resonance (EPR) spectroscopy to the elucidation of free radical and other processes.
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作者 Bernard A.Goodman Chahan Yeretzian +1 位作者 Klaus Stolze Deng Wen 《Agricultural Sciences》 2013年第8期433-442,共10页
Coffees and teas are beverages that are both exceptionally rich in antioxidant molecules, and are also both associated with beneficial health effects. Thus although the quality characteristics of these beverages are c... Coffees and teas are beverages that are both exceptionally rich in antioxidant molecules, and are also both associated with beneficial health effects. Thus although the quality characteristics of these beverages are conventionally assessed on the basis of their sensory properties, their antioxidant contents represent an additional and increasingly valued attribute of quality based on their contributions to healthy diets. Both beverages are prepared by hot water extraction of a pure plant-derived product, and thus their compositions can potentially change quite rapidly as a result of oxidation in contact with air. Oxidative processes often proceed via free radical intermediates, and sometimes also result in the formation of stable radical end-products;thus EPR spectroscopy is a convenient technique for investigating some of the various free radical reactions that occur in these beverages. This paper reviews progress that has been made in elucidating free radical processes that occur during the preparation and storage of coffees and teas, and the results are discussed in terms of quality criteria of the beverages. 展开更多
关键词 COFFEE TEA free radicals ANTIOXIDANTS EPR Spectroscopy QUALITY
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Elimination of Free Radicals and Immunity Enhancement with 644 nm (Red Colour) Radiation: A Randomised Controlled Clinical Trial
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作者 Samina T. Yousuf Azeemi Saleem Farooq Shaukat +1 位作者 Rubina Qasim Hadia Khawar 《Chinese Medicine》 2016年第1期10-15,共6页
Superoxide dismutase (SOD) is an important antioxidant enzyme present in all oxygen-metabolizing cells. The effect of different wavelengths on superoxide dismutase (SOD) has been reported previously which has shown to... Superoxide dismutase (SOD) is an important antioxidant enzyme present in all oxygen-metabolizing cells. The effect of different wavelengths on superoxide dismutase (SOD) has been reported previously which has shown to have a remarkable effect on immune system. Thus, after presenting solid scientific reasoning behind this therapeutic mode of treatment pertaining to the activity of SOD in the presence of 644 nm radiation, a randomised controlled clinical trial has been carried out which builds a unique relationship of 644 nm irradiated SOD with the elimination of free radicals and hence the enhancement of immunity, not only for curative treatment but also as a preventive tool against all those diseases related to the elimination of free radicals to get better immune system of the human body. This study was conducted in the department of Gynecology and obstetrics at Al-Khidmat Teaching Hospital Mansoorah, Lahore, Pakistan. 展开更多
关键词 Immunity System free radicals SOD Chromotherapy Red Colour (644 nm Radiation)
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Free Radical-Scavenging Properties and Antioxidant Activity of Fractions from Cranberry Products
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作者 Stéphane Caillet Guillaume Lorenzo +2 位作者 Jacinthe Coté Jean-Francois Sylvain Monique Lacroix 《Food and Nutrition Sciences》 2012年第3期337-347,共11页
Lipid peroxidation inhibition capacity and antiradical activity were evaluated in HPLC fractions of different polarity obtained from two cranberry juices and three extracts isolated from frozen cranberries and pomace ... Lipid peroxidation inhibition capacity and antiradical activity were evaluated in HPLC fractions of different polarity obtained from two cranberry juices and three extracts isolated from frozen cranberries and pomace containing antho-cyanins, water-soluble and apolar phenolic compounds, respectively. Compounds with close polarities were collected to obtain between three and four fractions from each juice or extract. The cranberry phenols are good free radi-cal-scavengers, but they were less efficient at inhibiting the lipid peroxidation. Of all the samples tested, the intermediate polarity fraction of extract rich in apolar phenolic compounds of fruit presented the highest antiradical activity while the most hydrophobic fractions of the anthocyanin-rich extract from fruit and pomace appeared to be the most efficient at inhibiting the lipid peroxidation. The antioxidant or pro-oxidant activity of fractions increased with the con-centration. The phenol polarity and the technological process to manufacture cranberry juice can influence the antioxidant and antiradical activities of fractions. 展开更多
关键词 HPLC Fractions Cranberry Juices Phenolic Extracts free radical Scavenging Capacity Antioxidant Activity
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Free radicals induced ultra-rapid synthesis of N-doped carbon sphere catalyst with boosted pyrrolic N active sites for efficient acetylene hydrochlorination
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作者 Yuxiang Bao Xiuhui Zheng +7 位作者 Jianlin Cao Shuo Li Yongxiao Tuo Xiang Feng Mingyuan Zhu Bin Dai Chaohe Yang De Chen 《Nano Research》 SCIE EI CSCD 2023年第5期6178-6186,共9页
Activated carbon-supported HgCl2 catalysts have seriously impeded the development of the polyvinyl chloride(PVC)industry due to the sublimation of Hg species and environmental pollution problems.Herein,the template-fr... Activated carbon-supported HgCl2 catalysts have seriously impeded the development of the polyvinyl chloride(PVC)industry due to the sublimation of Hg species and environmental pollution problems.Herein,the template-free and organic solvent-free strategy was devised to synthesize non-metallic based nitrogen-doped carbon(U-NC)sphere catalyst for acetylene hydrochlorination.This green strategy via ultrasonic chemistry initiates resin crosslinking reactions between aminophenol and formaldehyde resin by free radicals,leading to the ultra-rapid formation of U-NC with remarkably high pyrrolic N content in only 5 min.This U-NC catalyst exhibited an outstanding space-time-yield(1.6 gVCM·gcat^(−1)·h^(−1)),even comparable to the reported metallic catalyst.By combining kinetic analysis,advanced characterizations,density functional theory,it is found that the amount of pyrrolic N is in linear with C_(2)H_(2)conversion,pyrrolic N in U-NC can effectively improve acetylene hydrochlorination performance by mediating HCl adsorption.This work sheds new light on rationally constructing metal-free catalyst for acetylene hydrochlorination. 展开更多
关键词 acetylene hydrochlorination nitrogen-doped carbon ultrasonic chemistry free radical POLYMERIZATION
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Interfacial Reinitiation of Free Radicals Enables the Regeneration of Broken Polymeric Hydrogel Actuators
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作者 Baoyi Wu Huanhuan Lu +7 位作者 Yukun Jian Dachuan Zhang Yu Peng Jie Zhuo Xiaoxia Le Jiawei Zhang Patrick Théato Tao Chen 《CCS Chemistry》 CAS CSCD 2023年第3期704-717,共14页
Living organisms,from plants to animals,have inspired and guided the design and fabrication of polymeric hydrogels with biomimetic morphology,shape deformation,and actuation behavior.However,the existing polymeric hyd... Living organisms,from plants to animals,have inspired and guided the design and fabrication of polymeric hydrogels with biomimetic morphology,shape deformation,and actuation behavior.However,the existing polymeric hydrogels are fragile and vulnerable,which seriously hinders further application.Therefore,endowing hydrogels with a biomimetic self-growth property and regenerating the macroscopic shape of hydrogels after they suffer significant damage are highly desirable for the next generation of adaptive biomimetic hydrogels.Inspired by the tail regeneration of geckos,we herein report an efficient and universal strategy of interfacial diffusion polymerization(IDP),which can regenerate the polymeric layer at a solid–liquid interface,thereby growing new hydrogels on the existing hydrogel layers.Through changing the solvent viscosity and/or monomer type of the hydrogel precursor,diverse new hydrogels have been regenerated to endow the initial hydrogels with additional fluorescent functions and/or actuating properties.Due to the high efficiency and universality of IDP,an injured hydrogel actuator can be repaired,regenerated,and recovered to its initial condition,even after suffering severe damage such as cutting or piercing.We believe that the regeneration strategy of polymeric hydrogels will inspire the design of biomimetic materials and motivate the fabrication of the next generation of soft robots with adaptive and multifunctional properties. 展开更多
关键词 HYDROGELS biomimetics interface diffusion polymerization free radicals monitor
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Preparation of Curcumin Chitosan Nanoparticles and Its Effect on Free Radical Injury in Mice with Mycoplasma Pneumoniae Pneumonia
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作者 FU Jin-hua 《Chinese Journal of Biomedical Engineering(English Edition)》 CAS 2023年第3期100-108,共9页
Objective:Curcumin(Cur)and Chitosan(CS)were utilized as primary components for the production of curcumin chitosan nanoparticles.The impact of these nanoparticles on oxidative stress in mycoplasma pneumoniae-infected ... Objective:Curcumin(Cur)and Chitosan(CS)were utilized as primary components for the production of curcumin chitosan nanoparticles.The impact of these nanoparticles on oxidative stress in mycoplasma pneumoniae-infected mice was assessed.Methods:The drug loading and entrapment efficiency of Cur-CS nanoparticles were determined for various feeding ratios,and the release profiles of Cur-CS nanoparticles in different release media were investigated using the dynamic membrane dialysis method.The mycoplasma pneumoniae pneumonia(MPP)mouse model was created through the infection of mice with mycoplasma pneumoniae.The mice were then allocated randomly into five groups:a blank control group,an MPP model group,a low Cur-CS dose group,a middle Cur-CS dose group,and a high Cur-CS dose group,each consisting of 7 mice.The study compared the levels of antioxidant enzymes and phospholipid peroxide content in the lung tissue of mice across various experimental groups.Results:The findings indicated that the drug loading of nanoparticles escalated from 2.10%to 11.74%as the feed ratio of Cur to CS increased from 1∶20 to 1∶2.5.Concurrently,as drug loading increased,the entrapment efficiency of nanoparticles decreased from 85.33%to 58.92%.The cumulative release rate of Cur was 95.3%after 24 h,whereas the cumulative release rate of Cur-CS nanoparticles was only 94.3%after 48 h.Analysis of the lung tissue samples indicated that the levels of SOD[(76.17±9.36)U/ml,(86.23±10.09)U/ml,(98.06±11.12)U/ml]and GSH-Px[(19.75±2.22)U/ml,(23.92±2.53)U/ml,(27.23±2.67)U/ml]were significantly higher than those in the MPP model group(P<0.05).Conclusion:This suggests that curcumin chitosan nanoparticles may be suitable for antioxidant treatment of mycoplasma pneumoniae in mice,and can dose-dependently inhibit the release of oxygen free radicals in the lung tissue of MPP mice.This finding may offer a new avenue for the development of therapeutic drug carriers for MPP. 展开更多
关键词 curcumin(Cur) chitosan(CS) NANOPARTICLE mycoplasma pneumoniae pneumonia(MPP) free radicals
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A critical review on the application of biochar in environmental pollution remediation:Role of persistent free radicals(PFRs) 被引量:8
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作者 Kun Luo Ya Pang +5 位作者 Dongbo Wang Xue Li Liping Wang Min Lei Qi Huang Qi Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第10期201-216,共16页
Biochar as an emerging carbonaceous material has exhibited a great potential in environmental application for its perfect adsorption ability.However,there are abundant persistent free radicals(PFRs)in biochar,so the d... Biochar as an emerging carbonaceous material has exhibited a great potential in environmental application for its perfect adsorption ability.However,there are abundant persistent free radicals(PFRs)in biochar,so the direct and indirect PFRs-mediated removal of organic and inorganic contaminants by biochar was widely reported.In order to comprehend deeply the formation of PFRs in biochar and their interactions with contaminants,this paper reviews the formation mechanisms of PFRs in biochar and the PFRs-mediated environmental applications of biochar in recent years.Finally,future challenges in this field are also proposed.This review provides a more comprehensive understanding on the emerging applications of biochar from the viewpoint of the catalytic role of PFRs. 展开更多
关键词 BIOCHAR Organic and inorganic contaminants Persistent free radicals DEGRADATION Reactive oxygen species
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Free radical scavenging activity of Eagle tea and their flavonoids 被引量:4
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作者 Qiong Meng Zhengming Qian +4 位作者 Xiaoxiang Li Deqiang Li Weihua Huang Jing Zhao Shaoping Li 《Acta Pharmaceutica Sinica B》 SCIE CAS 2012年第3期246-249,共4页
In this study,an online HPLC-DAD-MS coupled with 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid)diammonium salt(A BTS)assay was employed for evaluating free radical scavenging activity of Eagle tea and their ... In this study,an online HPLC-DAD-MS coupled with 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid)diammonium salt(A BTS)assay was employed for evaluating free radical scavenging activity of Eagle tea and their active components.Twenty-three chromatographic peaks were detected,and nineteen components had free radical scavenging activity.Among them,eight compounds were identified as flavonoids(hyperin,isoquercitrin,quercitrin,quercetin,kaempferol),catechins,chlorogenic acid and epicatechin based on MS data and standard chromatographic characters. 展开更多
关键词 ABTS Eagle tea FLAVONOIDS free radical scavenging HPLC
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