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环境心理学有关问题的探讨 被引量:8
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作者 马逊风 黄冬梅 +1 位作者 黄钰 何子光 《吉林师范大学学报(自然科学版)》 2004年第1期33-36,共4页
随着环境问题的日益突出,作为新型的、交叉性的学科"环境心理学"已悄然向我们走来.本文尝试性的就环境心理学的概念、研究内容、研究方法和研究意义等基本问题作以初步的探讨.
关键词 环境心理学 环境问题 环境事件 心理健康 环境应激物
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从心理学视角探析中国人的忍 被引量:1
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作者 史艳琴 《山西高等学校社会科学学报》 2015年第6期78-81,85,共5页
文章提出忍的心理学认知模式。在这种模式下,应激物系统作为自变量,对忍的认知评价系统和反应系统是因变量。它有两级评价——初级评价和次级评价;四种心理机制——压抑或抑制、满足的延宕、认知转化、策略性反应;五条外部评价标准——... 文章提出忍的心理学认知模式。在这种模式下,应激物系统作为自变量,对忍的认知评价系统和反应系统是因变量。它有两级评价——初级评价和次级评价;四种心理机制——压抑或抑制、满足的延宕、认知转化、策略性反应;五条外部评价标准——道德规范、团体舆论、群体规章制度、禁忌与忌讳、关系等作为中介变量;五条内部心理体验——对个体的重要性、个体对自身角色地位的认知、个体的归因倾向、个体的忍观念、忍的预期结果。它包含认知反应、情绪反应、行为反应三个反应系统。忍与西方的自我控制延缓满足理论有所不同。 展开更多
关键词 应激物 认知评价 情绪调控 行为反应
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畜禽应用免疫研究近况
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作者 崔尚金 韩英 《畜牧兽医科技信息》 1996年第13期2-3,共2页
集约化生产是畜牧业发展的方向,畜牧业工作者业已认识到:1、把饲养的动物作为一个群体来诊断、防疫与治疗,而不是个别对待;2、许多疾病都是由多种综合因素引起的,而不是单一的传染源引起;3、最大限度地保持畜禽健康必须进行综合防治。... 集约化生产是畜牧业发展的方向,畜牧业工作者业已认识到:1、把饲养的动物作为一个群体来诊断、防疫与治疗,而不是个别对待;2、许多疾病都是由多种综合因素引起的,而不是单一的传染源引起;3、最大限度地保持畜禽健康必须进行综合防治。在此思想指导下,应用免疫学已由传统的抗感染发展到适合于多种非传染性疾病,集防、治和调节为一体,成为畜牧业和预防兽医学上的一个重要领域。现将几方面简述如下。 展开更多
关键词 研究近况 疫苗 交感神经系统 应激物 畜禽 免疫机理 集约化生产 免疫调节剂 免疫系统 非传染性疾病
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运动员对紧急状态的迅速调整
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作者 肯特·杰亚当 郭燕 《体育科技信息》 2002年第3期35-35,共1页
培养运动员个人处理紧急状况的应变能力。其中包括内部应激物和外部应激物,内部应激物包括心率、呼吸、睡眠与清醒的循环、饥饱、生物节律、内分泌的稳定程度和心理状态;外部应激物,例如工作、社会环境、物价的涨落、教练与运动员的... 培养运动员个人处理紧急状况的应变能力。其中包括内部应激物和外部应激物,内部应激物包括心率、呼吸、睡眠与清醒的循环、饥饱、生物节律、内分泌的稳定程度和心理状态;外部应激物,例如工作、社会环境、物价的涨落、教练与运动员的相互影响,运动创伤以及每天在学校里发生的各种事件,通过自身及教练的调节以加强其心理状态、动机等方面的改善,从而达到最佳状态。 展开更多
关键词 运动员 紧急状态 灵活多变性 应激物 压力
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8-Hydroxydeoxyguanosine:Not mere biomarker for oxidative stress,but remedy for oxidative stress-implicated gastrointestinal diseases 被引量:30
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作者 Chan-Young Ock Eun-Hee Kim +3 位作者 Duck Joo Choi Ho Jae Lee Ki-Baik Hahm Myung Hee Chung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第4期302-308,共7页
Reactive oxygen species (ROS) attack guanine bases in DNA easily and form 8-hydroxydeoxyguanosine (8-OHdG), which can bind to thymidine rather than cytosine, based on which, the level of 8-OHdG is gen- erally rega... Reactive oxygen species (ROS) attack guanine bases in DNA easily and form 8-hydroxydeoxyguanosine (8-OHdG), which can bind to thymidine rather than cytosine, based on which, the level of 8-OHdG is gen- erally regarded as a biomarker of mutagenesis conse- quent to oxidative stress. For example, higher levels of 8-OHdG are noted in Helicobacter pylori-associated chronic atrophic gastritis as well as gastric cancer. However, we have found that exogenous 8-OHdG can paradoxically reduce ROS production, attenuate the nuclear factor-KB signaling pathway, and ameliorate the expression of proinflammatory mediators such as interleukin (IL)-I, IL-6, cyclo-oxygenase-2, and induc- ible nitric oxide synthase in addition to expression of nicotinamide adenine dinucleotide phosphate oxidase (NOX)-I, NOX organizer-1 and NOX activator-1 in vari- ous conditions of inflammation-based gastrointestinal (GI) diseases including gastritis, inflammatory bowel disease, pancreatitis, and even colitis-associated carci- nogenesis. Our recent finding that exogenous 8-OHdG was very effective in either inflammation-based or oxidative-stress-associated diseases of stress-related mucosal damage has inspired the hope that synthetic 8-OHdG can be a potential candidate for the treatment of inflammation-based GI diseases, as well as the pre- vention of inflammation-associated GI cancer. In this editorial review, the novel fact that exogenous 8-OHdG can be a functional molecule regulating oxidative- stress-induced gastritis through either antagonizing Rac-guanosine triphosphate binding or blocking the signals responsible for gastric inflammatory cascade is introduced. 展开更多
关键词 8-hydroxydeoxyguanosine Oxidative stress INFLAMMATION CARCINOGENESIS Prevention
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Effect of psychological stress on gastric motility assessed by electrical bio-impedance 被引量:6
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作者 María Raquel Huerta-Franco Miguel Vargas-Luna +2 位作者 Juana Berenice Montes-Frausto Ismael Morales-Mata Lorena Ramirez-Padilla 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第36期5027-5033,共7页
AIM:To evaluate gastric motility using electrical bioimpedance(EBI) and gastric changes as a result of stress induced by psychological tests.METHODS:A group of 57 healthy women,aged 40-60 years,was recruited,and a cli... AIM:To evaluate gastric motility using electrical bioimpedance(EBI) and gastric changes as a result of stress induced by psychological tests.METHODS:A group of 57 healthy women,aged 40-60 years,was recruited,and a clinical history and physical examination were performed.The women were free from severe anxiety,chronic or acute stress,severe depression,mental diseases and conditions that affect gastric activity.The women were evaluated under fasting conditions,and using a four-electrode configuration,the gastric signals were obtained through a BIOPAC MP-150 system.The volunteers were evaluated using the following paradigm:basal state,recording during the Stroop Test,intermediate resting period,recording during the Raven Test,and a final resting period.We analyzed the relative areas of the frequency spectrum:A1(1-2 cpm),A2(2-4 cpm),A3(4-8 cpm),and A4(8-12 cpm),as well as the median of area A2 + A3.The data were analyzed by an autoregressive method using a Butterworth filter with MatLab and Origin.Analysis of variance(ANOVA) and Friedman ANOVA(for nonparametric variables) were performed;in addition,pairs of groups were compared using the T dependent and Wilcoxon T tests.RESULTS:The results of the main values of area A2 were not significantly different comparing the five steps of the experimental paradigm.Nevertheless,there was a tendency of this A2 region to decrease during the stress tests,with recuperation at the final resting step.When an extended gastric region was considered(1-4 cpm),significant differences with the psychological stress tests were present(F = 3.85,P = 0.005).The A3 region also showed significant changes when the stress psychological tests were administered(F = 7.25,P < 0.001).These differences were influenced by the changes in the adjacent gastric region of A2.The parameter that we proposed in previous studies for the evaluation of gastric motility by electrical bio-impedance(EBI) was the median of the area under the region from 2 to 8 cpm(A2 + A3).The mean values of these frequencies(median of the A2 + A3 area) with the stress test showed significant changes(F = 5.5,P < 0.001).The results of the WilcoxonT test for the A4 area parameter,which is influenced by the breathing response,changed significantly during the Raven stress test(P < 0.05).CONCLUSION:We confirm that the gastric response to acute psychological stress can be evaluated by short-term EBI. 展开更多
关键词 Psychological stress BIO-IMPEDANCE Gas-tric motility
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p53 antibodies,metallothioneins,and oxidative stress markers in chronic ulcerative colitis with dysplasia 被引量:6
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作者 Hala E Hamouda Soha S Zakaria +2 位作者 Saber A Ismail Mahmoud A Khedr Wael W Mayah 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第19期2417-2423,共7页
AIM:To investigate the role of p53 antibodies (p53Abs),metallothioneins (MTs) and oxidative stress markers in the early detection of dysplasia in chronic ulcerative colitis (UC).METHODS:The study included 30 UC patien... AIM:To investigate the role of p53 antibodies (p53Abs),metallothioneins (MTs) and oxidative stress markers in the early detection of dysplasia in chronic ulcerative colitis (UC).METHODS:The study included 30 UC patients,15 without dysplasia (group Ⅱ) and 15 with dysplasia (group Ⅲ),in addition to 15 healthy volunteers (group Ⅰ,control subjects).The enzyme-linked immunosorbent assay technique was used to measure serum p53Abs and MTs,while advanced oxidation protein products (AOPPs),and reduced glutathione (GSH) levels were measured by spectrophotometric method in all subjects.RESULTS:In group Ⅱ and group Ⅲ compared to group Ⅰ,there were significant increases in serum levels of AOPPs (145.94 ± 29.86 μmol/L and 192.21 ± 46.71 μmol/L vs 128.95 ± 3.06 μmol/L,P < 0.002 and P <0.001,respectively),MTs (8.18 ± 0.35 μg/mL and 9.20 ± 0.58 μg/mL vs 6.12 ± 0.25 μg/mL,P < 0.05 and P < 0.05,respectively),and p53Abs (20.19 ± 3.20 U/mL and 34.66 ± 1.34 U/mL vs 9.42 ± 1.64 U/mL,P < 0.001 and P < 0.001,respectively).There were significantly higher levels of AOPPs (P < 0.05) and p53Abs (P < 0.001) in UC patients with dysplasia compared to those without dysplasia,while MTs showed no significant difference between the 2 groups (P > 0.096).In contrast,GSH levels showed a significant decrease in both patients' groups (1.87 ± 0.02 μmol/mL and 1.37 ± 0.09 μmol/mL vs 2.49 ± 0.10 μmol/mL,P < 0.05 and P < 0.05 in groups Ⅱ and Ⅲ,respectively) compared with group Ⅰ,and the levels were significantly lower in group Ⅲ than group Ⅱ (P < 0.05).There was a positive correlation between AOPPs and both MTs (r=0.678,P < 0.001) and p53Abs (r=0.547,P < 0.001),and also between p53Abs and MTs (r=0.739,P < 0.001).There was a negative correlation between AOPPs and GSH (r =-0.385,P < 0.001),and also between GSH and both MTs (r=-0.662,P < 0.001) and p53Abs (r=-0.923,P < 0.001).CONCLUSION:Oxidative stress and oxidative cellular damage play an important role in the pathogenesis of chronic UC and the associated carcinogenetic process.p53Abs levels could help in early detection of dysplasia in these conditions. 展开更多
关键词 Ulcerative colitis Advanced oxidation protein products Reduced glutathione METALLOTHIONEIN
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Kinetics of Coil-to-Globule Transition of DansyI-Labeled Poly(N-isopropyl- acrylamide) Chains in Aqueous Solution
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作者 李春亮 叶晓东 +1 位作者 丁延伟 刘世林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第4期389-397,I0003,共10页
The coil-to-globule transition of thermally sensitive linear poly(N-isopropylacrylamide) (PNIPAM) labeled with dansyl group is induced by 1.54 μm laser pulses (widths10 ns). The dansyl group is used to follow t... The coil-to-globule transition of thermally sensitive linear poly(N-isopropylacrylamide) (PNIPAM) labeled with dansyl group is induced by 1.54 μm laser pulses (widths10 ns). The dansyl group is used to follow the transition kinetics because its fluorescence intensity is very sensitive to its micro-environment. As the molar ratio of NIPAM monomer to dansyl group increases from 110 to 300, the effect of covalently attached dansyl fluorophores on the transition decreases. In agreement with our previous study in which we used 8-anilino- l-naphthalensulfonic acid ammonium salt free in water as a fluorescent probe, the current study reveals that the transition has two distinct stages with two characteristic times, namely, Tfast≈0.1 ms, which can be attributed to the nucleation and formation of some "pearls" (locally contracting segments) on the chain, and tslow≈0.5 ms, which is related to the merging and coarsening of the "pearls".Tfast is independent of the PNIPAM chain length over a wide range (Mw=2.8× 10^6-4.2 × 10^7 g/mol). On the other hand, Tslow only slightly increases with the chain length. 展开更多
关键词 Fluorescence labeling Laser light scattering Phase transition Stimuli-sensitive polymer
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Relationship Between Ca^(2+) and Plant Ethylene Response 被引量:1
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作者 张艳萍 朱本忠 罗云波 《Acta Botanica Sinica》 CSCD 2002年第4期422-426,共5页
The relationship between Ca 2+ and ethylene response was investigated through analyzing the effect of Ca 2+ on the response to ethylene in etiolated tomato (Lycopersicon esculentum Mill cv. Lichun) seedling grow... The relationship between Ca 2+ and ethylene response was investigated through analyzing the effect of Ca 2+ on the response to ethylene in etiolated tomato (Lycopersicon esculentum Mill cv. Lichun) seedling grown in darkness. When the etiolated tomato seedlings were treated with different concentrations of Ca 2+, the 'triple response' phenotype, ethylene production, the expression of ethylene receptor gene NEVER-RIPE (NR) and the content of cytosolic CaM were determined. With the concentration of Ca 2+ in the culture medium increasing from 0 mmol/L to 3.8 mmol/L, the 'triple response' phenotype of etiolated tomato seedling was correspondingly strengthened; meanwhile the ethylene production, the amount of NR gene expression and the concentration of CaM increased respectively. However, when the concentration of Ca 2+ was increased from 3.8 mmol/L to 10 mmol/L, the phenotype of 'triple response', ethylene production, NR gene expression, and the CaM content didn't increase further, but decreased consequently. The results indicated that the effect of Ca 2+ on the ethylene triple response in etiolated tomato seedling was relevant to ethylene biosynthesis and ethylene receptor gene expression which were influenced by applied Ca 2+, and these effects might be mediated through the change of CaM concentration in plant cell. 展开更多
关键词 Ca 2+ triple response ethylene signal transduction CAM
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STUDY ON THE ANTI-TUMOR EFFICACY INDUCED BY HEAT SHOCK PROTEIN 70-PEPTIDE COMPLEXES DERIVED FROM TUMOR CELLS 被引量:6
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作者 傅庆国 张玮 +2 位作者 孟凡东 郭仁宣 姚振宇 《Chinese Medical Sciences Journal》 CAS CSCD 2002年第3期153-156,共4页
OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric an... OBJECTIVE: To study the efficacy and explore the mechanism of the anti-tumor immunity elicited by heat shock protein 70-peptide complexes (HSP70-PC) derived from tumor cells. METHODS: Cells culture, flow cytometric analysis, affinity chromatography for protein purification, SDS-PAGE, Western-blotting and animal experiment were used. RESULTS: HSP70-PC immunization rendered protective effect to both naive tumorl-bearing mice. All of the naive mice obtained complete resistance to Hcaf cell attack; 40% of the tumor-bearing mice survived for over 90 days, whereas the mice of control group died within 2 weeks (P 展开更多
关键词 NEOPLASM heat shock protein 70 peptide complexes tumor vaccineObjective. To study the efficacy and explore the mechanism of the anti tumor immunity elicited by heat shock protein 70 peptide complexes (HSP70 PC) derived from tumor cells. M
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Oxidative stress responses of submerged macrophyte Vallisneria asiatica to different concentrations of cyanobacteria 被引量:2
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作者 康彩霞 KUBA Takahiro +3 位作者 郝爱民 ISERI Yasushi 李春杰 张振家 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第2期364-371,共8页
In a 10-day aquarium experiment, this investigation examines macrophyte restoration in eutrophic Lake Taihu, the physiological effects of different plant biomass levels and of increasing natural cyanobacterial concent... In a 10-day aquarium experiment, this investigation examines macrophyte restoration in eutrophic Lake Taihu, the physiological effects of different plant biomass levels and of increasing natural cyanobacterial concentrations on a submerged macrophyte, Vallisneria asiatica. Cyanobacterial stress suppressed the superoxide dismutase (SOD) activity of the plant's leaves and induced the catalase (CAT) and peroxidase (POD) activities of its roots. The soluble protein content in V. asiatica decreased with an increase in natural cyanobacterial concentrations, whereas the malonaldehyde (MDA) increased significantly at chlorophyll a (Chl a) concentrations of 222 and 262 μg/L in water. V. asiatica adapted to the stress caused by cyanobacterial concentrations by adjusting its antioxidant defense system to remove the excessive reactive oxygen species when the algal Chl a concentration was 〉109 μg/L. Additionally, high biomass of V. asiatica (2 222 g FW/m^2) can inhibit the reproduction of cyanobacteria more significantly than low biomass (1 111 g FW/m^2). High biomass of V. asiatica increased the oxidative stress in an individual plant when the initial Chl a concentration in the water reached 222 and 262 μg/L, as expressed by the increased MDA in leaves, compared with low biomass of K asiatica. This provides a basis for controlling cyanobacterial concentrations and V. asiatica biomass for the recovery of V. asiatica in eutrophic Lake Taihu. 展开更多
关键词 algal bloom physiological response macrophyte restoration Vallisneria asiatica
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THE EFFECT OF LOW DOSE FAST NEUTRONS IRRADIATION ON THE GROWTH OF TILAPIA NILOTICA
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作者 武珊 贾洛武 +1 位作者 张小戎 郭磊 《Transactions of Tianjin University》 EI CAS 1995年第1期67+63-67,共6页
This paper presents the effects of the low-dose irradiation on Tilapia Nilotica. In laboratory experiments the Tilapia Nilotica irradiated by integrated flux of fast neutrons 1×10 9 neutrons/m2 and 1 ×10 10... This paper presents the effects of the low-dose irradiation on Tilapia Nilotica. In laboratory experiments the Tilapia Nilotica irradiated by integrated flux of fast neutrons 1×10 9 neutrons/m2 and 1 ×10 10 neutrons/m2 gave a growth rate more than 40% and 32 % compared with those of controls respectively. The yield of the irradiated Tilapia Nilotica growing with non-irradiated carps and silver carps in a mixed feed condition increased by 8. 6%, 157% and 11. 0% more than those of the controls in the pilot test. The survival rate increases by 21. 8%, 149% and 16. 2% for the aboye-mentioned three species. An increased yield of 52 098 kg fish under irradiation with low dose was obtained in 18. 7 hectare water surface. The results of biological experiments show that the main organic coefficients of the Tilapia Nilotica are greater than those of the controls, and this may be related to the increase of the capabilities of metabolism and resistance to diseases. 展开更多
关键词 ilapia Nilotica HORMESIS ionizing radiation biological effect NEUTRON
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Body awareness therapy: A new strategy for relief of symptoms in irritable bowel syndrome patients 被引量:1
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作者 EM Eriksson IE Mller +2 位作者 RH Sderberg HT Eriksson GK Kurlberg 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第23期3206-3214,共9页
AIM: To compare irritable bowel syndrome (IBS) pa- tients with apparently healthy persons and to evaluate body awareness therapy, which is a physiotherapeutic remedy focusing on normalising tensions in the body, for t... AIM: To compare irritable bowel syndrome (IBS) pa- tients with apparently healthy persons and to evaluate body awareness therapy, which is a physiotherapeutic remedy focusing on normalising tensions in the body, for the treatment of IBS with the hypothesis that altered body tension is associated with the syndrome. METHODS: Twenty-one IBS patients received body awareness therapy two hours weekly for 24 wk. At base- line as well as after 12 and 24 wk, they underwent ex- aminations including resource oriented body examination in combination with body awareness scale evaluation and f illed in gastrointestinal and psychological symptom questionnaires. Saliva cortisol was analysed. A group of 21 apparently healthy persons underwent the same ex- aminations once. RESULTS: Compared to the apparently healthy group, IBS patients scored higher at baseline for gastrointestinal and psychological symptoms. They showed more often alterations in normal body tension patterns, as well as deviating cortisol slopes in saliva. After 24 wk of body awareness therapy, their gastrointestinal and psychologi- cal symptoms were reduced overall. Somatic symptoms decreased in parallel with depressive symptoms. Whole body pain score decreased, coping ability as well as bio- chemical stress markers improved. CONCLUSION: IBS patients scored higher for gastroin- testinal and psychological symptoms, and presented with altered biochemical stress markers. Their body tension deviated compared to healthy controls. Furthermore,body awareness therapy gave relief of both somatic com- plaints, psychological symptoms and normalised body tension. These findings indicate that distorted tension constitutes an important part of the symptoms in IBS. 展开更多
关键词 Irritable bowel syndrome Pain CORTISOL PHYSIOTHERAPY Body awareness therapy PSYCHOSOMATICS Gastrointestinal tract Stress
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Dual function of Arabidopsis A TAF1 in abiotic and biotic stress responses 被引量:60
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作者 Yaorong Wu Zhiyong Deng +8 位作者 Jianbin Lai Yiyue Zhang Cuiping Yang Bojiao Yin Qingzhen Zhao Ling Zhang Yin Li Chengwei Yang Qi Xie 《Cell Research》 SCIE CAS CSCD 2009年第11期1279-1290,共12页
NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid (... NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid (ABA), methyl jasmonate, mechanical wounding, and Botrytis cinerea infection. Significant induction of ATAF1 was found in an ABA-deficient mutant aba2 subjected to drought or high salinity, revealing an ABA-independent mechanism of expression. Arabidopsis ATAFl-overexpression lines displayed many altered phenotypes, including dwarfism and short primary roots. Furthermore, in vivo experiments indicate that ATAF1 is a bonafide regulator modulating plant responses to many abiotic stresses and necrotrophic-pathogen infection. Overexpression of ATAF1 in Arabidopsis increased plant sensitivity to ABA, salt, and oxidative stresses. Especially, ATAF1 overexpression plants, but not mutant lines, showed remarkably enhanced plant tolerance to drought. Additionally, ATAF1 overexpression enhanced plant susceptibility to the necrotrophic pathogen B. cinerea, but did not alter disease symptoms caused by avirulent or virulent strains of P. syringae pv tomato DC3000. Transgenic plants overexpressing ATAF1 were hypersensitive to oxidative stress, suggesting that reactive oxygen intermediates may be related to ATAFl-mediated signaling in response to both pathogen and abiotic stresses. 展开更多
关键词 abiotic stress ARABIDOPSIS ATAF1 biotic stress
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Bile acids:Chemistry,physiology,and pathophysiology 被引量:48
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作者 Maria J Monte Jose JG Marin +1 位作者 Alvaro Antelo Jose Vazquez-Tato 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第7期804-816,共13页
The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological characteristics.They are synthesized by the liver from cholesterol through several ... The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological characteristics.They are synthesized by the liver from cholesterol through several complementary pathways that are controlled by mechanisms involving finetuning by the levels of certain bile acid species.Although their best-known role is their participation in the digestion and absorption of fat,they also play an important role in several other physiological processes.Thus,genetic abnormalities accounting for alterations in their synthesis,biotransformation and/or transport may result in severe alterations,even leading to lethal situations for which the sole therapeutic option may be liver transplantation.Moreover,the increased levels of bile acids reached during cholestatic liver diseases are known to induce oxidative stress and apoptosis,resulting in damage to the liver parenchyma and,eventually,extrahepatic tissues.When this occurs during pregnancy,the outcome of gestation may be challenged.In contrast,the physical-chemical and biological properties of these compounds have been used as the bases for the development of drugs and as pharmaceutical tools for the delivery of active agents. 展开更多
关键词 CHOLESTASIS CHOLESTEROL Liver METABOLISM Transport
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Role of MGST1 in reactive intermediate-induced injury 被引量:3
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作者 Courtney S Schaffert 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第20期2552-2557,共6页
Microsomal glutathione transferase (MGST1, EC 2.5.1.18) is a membrane bound glutathione transferase extensively studied for its ability to detoxify reactive intermediates, including metabolic electrophile intermediate... Microsomal glutathione transferase (MGST1, EC 2.5.1.18) is a membrane bound glutathione transferase extensively studied for its ability to detoxify reactive intermediates, including metabolic electrophile intermediates and lipophilic hydroperoxides through its glutathione dependent transferase and peroxidase activities. It is expressed in high amounts in the liver, located both in the endoplasmic reticulum and the inner and outer mitochondrial membranes. This enzyme is activated by oxidative stress. Binding of GSH and modification of cysteine 49 (the oxidative stress sensor) has been shown to increase activation and induce conformational changes in the enzyme. These changes have either been shown to enhance the protective effect ascribed to this enzyme or have been shown to contribute to cell death through mitochondrial permeability transition pore formation. The purpose of this review is to elucidate how one enzyme found in two places in the cell subjected to the same conditions of oxidative stress could both help protect against and contribute to reactive oxygen species-induced liver injury. 展开更多
关键词 Microsomal glutathione transferase 1 Oxidative stress Mitochondrial permeability transition GLUTATHIONE Liver injury
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A Review of Effects of Heat Stress on Substance and Energy Metabolism in Muscle 被引量:1
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作者 Shiyong WU Zhi FANG +2 位作者 Bo XUE Longzhou LIU Ye YANG 《Agricultural Science & Technology》 CAS 2015年第5期1011-1013,共3页
Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism... Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism of proteins, glucose, fat and energy in skeletal muscle and related mechanisms so as to provide theoretical guidance for alleviating heat stress and improving production performance of animal suffering from heat stress. 展开更多
关键词 Heat stress MUSCLE Substance metabolism Energy metabolism
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Stark Effect Dependence on Hydrogenic Impurities in GaAs Parabolic Quantum-Well Wires 被引量:1
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作者 WANG Sheng WEI Guo-Zhu HAN Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期953-959,共7页
The ground-state and lowest excited-state binding energies of a hydrogenic impurity in GaAs parabolic quantum-well wires (Q WWs) subjected to external electric and magnetic fields are investigated using the finite-d... The ground-state and lowest excited-state binding energies of a hydrogenic impurity in GaAs parabolic quantum-well wires (Q WWs) subjected to external electric and magnetic fields are investigated using the finite-difference method within the quasi-one-dimensional effective potential model. We define an effective radius Pen of a cylindrical QWW, which can describe the strength of the lateral confinement. For the ground state, the position of the largest probability density of electron in x-y plane is located at a point, while for the lowest excited state, is located on a circularity whose radius is Pen. The point and circularity are pushed along the left haft of the center axis of the quantum-well wire by the electric field dire ted along the right half. When an impurity is located at the point or within the circularity, the ground-state or lowest excited-state binding energies are the largest; when the impurity is apart from the point or circularity, the ground-state or lowest excited-state binding energies start to decrease. 展开更多
关键词 hydrogenic impurity quantum-well wire magnetic field binding energy
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Biodegradation of natural and synthetic estrogens in moving bed bioreactor 被引量:2
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作者 Mohammad Mehdi Amin Bijan Bina +2 位作者 Karim Ebrahim Zeynab Yavari Farzaneh Mohammadi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第2期393-399,共7页
Estrogen hormones as a group of endocrine disruptive compounds (EDC) can interfere with endocrine system in humans and animals. The goal of this study was to investigate the elimination rate of Estrone (El), 17β-... Estrogen hormones as a group of endocrine disruptive compounds (EDC) can interfere with endocrine system in humans and animals. The goal of this study was to investigate the elimination rate of Estrone (El), 17β-estradiol (E2) and 17α-ethinyl estradiol (EE2) in Moving Bed Bioreactor (MBBR). These analytes extracted by Dispersive Liquid-Liquid Microextraction (DLLME) technique, followed by derivatization, and detected by GC/MS. Estrogen removal efficiency in MBBR improved at high solid retention times (SRTs), which notion is owing to development ofnitrification. Estrogenspecificremovalratewasbetween 0,22-1.45μg.(gVSS) 1.d -1 for natural and synthetic hormones. The adsorption rate was 0.9%-3.2% 0-1.3%, and 0.7%-5.7% for E1, E2, and EE2, respectively. In addition, the biodegradation rates were more than 95% for these compounds. These results illustrated that in MBBR, the hiodegradation and the adsorption to biomass are considered as two significant routes for elimination of estrogenic compounds. As a whole, the deterioration rate of estrogens enhanced by MBBR compared to other biological wastewater treatment processes such as conventional activated sludge. 展开更多
关键词 Estrogen hormones Adsorption Biodegradation Nitrification
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Blueberry Extract Reduces Oxidative Stress in Patients with Metabolic Syndrome
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作者 Raul Francisco Pastor Gonzalez E +6 位作者 Cassini M. S. Pastor I Saure M Saavedra E. Siman Menem M. I. Drago S Iermoli R. H 《Journal of Life Sciences》 2016年第3期145-152,共8页
Oxidative stress is a health condition that could potentially harm the patient, and it is defined as the lack of balance between the production of oxygen free radicals, which rises, and antioxidant defenses, which are... Oxidative stress is a health condition that could potentially harm the patient, and it is defined as the lack of balance between the production of oxygen free radicals, which rises, and antioxidant defenses, which are in decrease. Metabolic syndrome implies a variety of risk factors that are based on abdominal obesity and insulin resistance. Moreover, the importance of metabolic syndrome is emphasized due to the fact that it presents an increase in oxidative stress, which is produced by the sum of alterations that each risk factor produces within the metabolic syndrome pathology. Reducing oxidative stress in these patients is currently one of the most interesting challenges of cardiovascular and metabolic therapeutics, because it is a molecular biology alteration that is not generally diagnosed and, therefore, not treated. The increasing incidence of overweight and obesity cause an increase in the incidence of metabolic syndrome, thus turning into a huge problem that keeps growing at alarming proportions. This syndrome's incidence oscillates between 20 and 40%, depending on the gender, age, ethnic group, and diagnostic criteria used for the definition of the disease. Prospective studies show that metabolic syndrome doubles the risk of cardiovascular disease and causes a five-fold increase in the risk of developing type 2 diabetes. With the aim of decreasing the oxidative stress caused by metabolic syndrome, we investigated the effect of antioxidant protection in DNA repair and cell membranes through the use of blueberry extract, which is the fruit with the highest antioxidant capacity, in patients with metabolic syndrome. Thirty patients were studied for a period of 6 months of intervention, and it could be demonstrated that they showed a highly significant decrease in the damage produced to the DNA, which was measured by the urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the damage caused to the vascular endothelium and cell membranes, which was measured through the urinary excretion of F2-isoprostane. Based on our knowledge, this investigation is the first one to show that lyophilized blueberry extract (BlueKing~) as a dietary supplement, with meals, is an additional therapeutic tool of great value for the treatment of oxidative stress through DNA and cell membrane protection in patients with metabolic syndrome. 展开更多
关键词 Metabolic syndrome urinary biomarkers of oxidative stress BLUEBERRIES antioxidants.
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