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中国文学的后发现代性语境 被引量:8
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作者 张荣翼 《学术月刊》 CSSCI 北大核心 2007年第1期91-96,共6页
后发现代性是在假定现代性是一种普泛化的、全球性的过程和社会发展性质的情况下,针对并非原发的现代性,也就是受到现代性的影响而兴起的现代性运动而提出的。后发现代性作为当今中国文学的语境,它成为文学创作的基点,同时也应该作为文... 后发现代性是在假定现代性是一种普泛化的、全球性的过程和社会发展性质的情况下,针对并非原发的现代性,也就是受到现代性的影响而兴起的现代性运动而提出的。后发现代性作为当今中国文学的语境,它成为文学创作的基点,同时也应该作为文学研究的基点。后发现代性在积极跟进现代性这样一个目标的前提下,也有着不同于原发状态的现代性的特性。既要承认席卷全球的现代性对于全球所在之处的共同影响力,也要充分考虑到并非原发的现代性对于所在国家文学的特殊影响。 展开更多
关键词 代性 发现代性 语境 中国文学
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A concept analysis of vicarious resilience in mental health nursing
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作者 Nora Ghalib AlOtaibi 《International Journal of Nursing Sciences》 CSCD 2024年第4期485-494,共10页
Objective:The introduction of the vicarious resilience concept in psychology and mental health nursing literature is a highly promising advancement.By utilizing this novel concept,experts in various domains can enhanc... Objective:The introduction of the vicarious resilience concept in psychology and mental health nursing literature is a highly promising advancement.By utilizing this novel concept,experts in various domains can enhance their comprehension of how to foster resilience in individuals by observing and learning from the resilience of others.This concept analysis aims to elucidate the concept of vicarious resilience in mental health nursing by defining its related attributes,antecedents,and consequences.Methods:Walker and Avant’s strategy for concept analysis method was used.This review specifically examined mental health nurse providers.A comprehensive literature search was performed in the PubMed,Medline,the Cochrane Library,and CINAHL databases.The inclusion criterion was Englishlanguage documents on vicarious resilience within mental health nursing.Results:A total of 24 articles were included.The concept’s attributes were empathy,hope,resourcefulness,awareness,and spirituality.Antecedents were associated with listening to patients’trauma narratives,self-care,self-awareness,and support from colleagues.Consequences were enhanced well-being,changes in life goals,adaptation,personal growth,and increased personal resilience.Currently,there is only one tool in the empirical reference.Conclusion:Interpreting the concept of vicarious resilience in mental health nursing and determining its characteristics can be utilized to design nursing interventions to develop vicarious resilience and enhance the quality of care in mental health facilities. 展开更多
关键词 Vicarious resilience Concept analysis Mental health Psychology health Nurses
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Comprehensive Understanding of Immune Cells in The Pathogenesis of Non-alcoholic Fatty Liver Disease
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作者 OUYANG Fei-Fan RASHEED Madiha +1 位作者 LI Bo DENG Yu-Lin 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第9期2082-2100,共19页
Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease,defined by several phases,ranging from benign fat accumulation to non-alcoholic steatohepatitis(NASH),which can lead to liver cancer and... Non-alcoholic fatty liver disease(NAFLD)is the most common chronic liver disease,defined by several phases,ranging from benign fat accumulation to non-alcoholic steatohepatitis(NASH),which can lead to liver cancer and cirrhosis.Although NAFLD is a disease of disordered metabolism,it also involves several immune cell-mediated inflammatory processes,either promoting and/or suppressing hepatocyte inflammation through the secretion of pro-inflammatory and/or anti-inflammatory factors to influence the NAFLD process.However,the underlying disease mechanism and the role of immune cells in NAFLD are still under investigation,leaving many open-ended questions.In this review,we presented the recent concepts about the interplay of immune cells in the onset and pathogenesis of NAFLD.We also highlighted the specific non-immune cells exhibiting immunological properties of therapeutic significance in NAFLD.We hope that this review will help guide the development of future NAFLD therapeutics. 展开更多
关键词 non-alcoholic fatty liver disease metabolically associated fatty liver disease(MAFLD) T cells myeloid cells mesenchymal stem cells
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医学体验与中国文学现代叙事 被引量:1
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作者 李良 《甘肃社会科学》 CSSCI 北大核心 2008年第2期65-68,共4页
20世纪中国文学和医学深刻扭结在一起。西方自然医学科学的借鉴体验,对于"弃医从文"或"亦医亦文"的人文作家具有深层规约和发展机制,造成文学叙事呈现出相当的冷静、理性和悲剧化品格,而这一点又恰恰和中国文学的... 20世纪中国文学和医学深刻扭结在一起。西方自然医学科学的借鉴体验,对于"弃医从文"或"亦医亦文"的人文作家具有深层规约和发展机制,造成文学叙事呈现出相当的冷静、理性和悲剧化品格,而这一点又恰恰和中国文学的现代性品质契合。 展开更多
关键词 医学体验 冷静 理性 悲剧 代性
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中国古典美学研究中的民族主义 被引量:2
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作者 邓军海 《关东学刊》 2017年第2期18-26,共9页
民族主义诉求主宰中国古典美学研究,非古典美学之福,乃古典美学之厄。企图以民族特殊性张扬中国古典美学,往往适得其反。摆出一副对抗西方姿态,以示政治正确,只会遮蔽自家眼界,而且会使得民族政治压倒学术研究。现代学人以国族视野审视... 民族主义诉求主宰中国古典美学研究,非古典美学之福,乃古典美学之厄。企图以民族特殊性张扬中国古典美学,往往适得其反。摆出一副对抗西方姿态,以示政治正确,只会遮蔽自家眼界,而且会使得民族政治压倒学术研究。现代学人以国族视野审视古人古书,既是对古典之歪曲,也是对古典之大不敬。中国古典美学研究欲摆脱民族政治之纠缠,须重回古人古书之天下视野,须摘掉民族主义这一现代眼镜,须还古书一份基本之尊重,把古书当古书来读。否则,中国古典美学研究只会沦为民族主义之张本。 展开更多
关键词 中国古典美学 民族主义 现代代性 以古视古 天下视野 国族视野
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Damage effect and mechanisms of cyclophosphamide to human neuroblastoma SH-SY5Y cells
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作者 LI Jiajia WANG Jiao +4 位作者 XIAO Wenyi WEI Donghui ZHANG Yongxiang JIANG Ning ZHOU Wenxia 《中国药理学与毒理学杂志》 CAS 北大核心 2024年第8期561-574,共14页
OBJECTIVE To investigate the damage effect and mechanisms of cyclophosphamide(CTX)and its active metabolite derivative 4-hydroperoxycyclophosphamide(4-HC)to human neuroblas⁃toma SH-SY5Y cells.METHODS SH-SY5Y cells wer... OBJECTIVE To investigate the damage effect and mechanisms of cyclophosphamide(CTX)and its active metabolite derivative 4-hydroperoxycyclophosphamide(4-HC)to human neuroblas⁃toma SH-SY5Y cells.METHODS SH-SY5Y cells were treated with CTX[0(cell control),0.01,0.1,1,5,10,20,40 and 80 mmol·L^(-1)]and 4-HC[0(cell control),0.01,0.1,1,5,10,20,40 and 80μmol·L^(-1)]for 48 h.Cell confluence and morphology were observed by the IncuCyte ZOOM system.Cell viability was assessed by CCK-8 assay.Lactate dehydrogenase(LDH)release was measured by LDH assay kit.SH-SY5Y cells were treated with CTX(0,1,5,10 and 20 mmol·L^(-1))and 4-HC(0,1,5,10 and 20μmol·L^(-1))for 48 h before cell proliferation was analyzed by 5-ethynyl-2′-deoxyuridine(EdU)staining assay.Immunofluorescence was employed to assess the levels of the DNA double-strand break markerγ-H2AX and to evaluate changes in mitochondrial membrane potential.SH-SY5Y cells were treated with CTX(0,1,5 and 10 mmol·L^(-1))and 4-HC(0,1,5 and 10μmol·L^(-1))for 48 h,and the alterations in glycolysis and oxidative phosphorylation levels were analyzed using the Seahorse XFe96 Analyzer.RESULTS Compared with the cell control group,cell confluence and cell viability were significantly reduced in the CTX and 4-HC groups(P<0.01),and the half-maximal inhibitory concentrations(IC50)for CTX and 4-HC were 4.44 mmol·L^(-1) and 4.78μmol·L^(-1),respectively.The release rate of LDH was signif⁃icantly increased while the percentage of EdU+cells was significantly reduced in the CTX and 4-HC groups(P<0.01).The percentage ofγ-H2AX+cells was significantly increased and mitochondrial membrane potential significantly decreased in the CTX and 4-HC group(P<0.05).Treatment with CTX and 4-HC resulted in reduced levels of maximum glycolytic capacity,glycolytic reserve,maximal respi⁃ration,and ATP production(P<0.05).CONCLUSION CTX and 4-HC exert significant cytotoxic effects on SH-SY5Y cells by disrupting cell membrane structure,impeding cell proliferation,and reducing cell viability.The mechanisms underlying these effects may involve intracellular DNA damage,disturbance of energy metabolism and mitochondrial dysfunction. 展开更多
关键词 CYCLOPHOSPHAMIDE 4-hydroperoxycyclophosphamide NEUROTOXICITY energy metabolism
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Enhancing Na^(+) diffusion dynamics and structural stability of O3-NaMn_(0.5)Ni_(0.5)O_(2)cathode by Sc and Zn dual-substitution
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作者 Bin-bin WANG Yi-ming FENG +8 位作者 Xin LUO Qun HUANG Zi-xing HOU Ya-qin WU Peng-yu WANG Yu-yang QI Qing-fei MENG Wei-feng WEI Liang-jun ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3344-3357,共14页
Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural ... Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN. 展开更多
关键词 layered oxide cathode Sc and Zn dual-substitution structural stability Na^(+)diffusion dynamics
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台湾的台湾现代派文学研究管窥
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作者 朱立立 《华侨大学学报(哲学社会科学版)》 2002年第3期112-120,共9页
台湾现代派文学的产生与发展伴随着不断的诠释、论争和批评过程 ,概括而言 ,台湾的台湾现代派文学研究有四种话语 :批判与否定现代主义 ,为现代派辩护 ;搁置意识形态与美学观念争执的形式批评 ;现代主义在台湾的历史寻踪与文学史定位。... 台湾现代派文学的产生与发展伴随着不断的诠释、论争和批评过程 ,概括而言 ,台湾的台湾现代派文学研究有四种话语 :批判与否定现代主义 ,为现代派辩护 ;搁置意识形态与美学观念争执的形式批评 ;现代主义在台湾的历史寻踪与文学史定位。在有关台湾现代派文学长久争议的背后 ,隐藏着一些重要的理论难题 :现代主义与现实主义的美学冲突 ; 展开更多
关键词 台湾文学 现代主义 话语 后发现代性
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两种微分形式下最优性条件的关系
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作者 高岩 《经济数学》 1998年第3期43-46,共4页
本文考虑具有不等式约束条件不可微优化问题,假定目标函数和约束函数既是Lipschitz的也是拟可微的.证明了该问题拟微分形式下的FritzJohn点必是Clarke广义梯度形式下的FritzJohn点.另外,还给出了拟微分和Clarke广义梯度之间的关系.
关键词 不可做优化 代性条件 Clarke广义梯度 拟微分
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Efficient in-situ end-functionalization of polydienes by isothiocyanate via neodymium mediated coordinative chain transfer polymerization system
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作者 ZHANG Xiu-hui DONG Jing +2 位作者 WANG Feng LIU Heng ZHANG Xue-quan 《合成橡胶工业》 CAS 2024年第4期347-347,共1页
End-functionalization of polydiene rubbers can not only improve its compatibility with inorganic fillers,but also enhance the overall mechanical properties.Nevertheless,for traditional neodymium(Nd)diene polymerizatio... End-functionalization of polydiene rubbers can not only improve its compatibility with inorganic fillers,but also enhance the overall mechanical properties.Nevertheless,for traditional neodymium(Nd)diene polymerization systems,it is highly challenging to achieve such end-functionalizations,because most of polydienyl chains are capped withη3-allyl-Nd moiety during the end of polymerization,which shows very poor reactivity with nucleophile compounds.We launched a new diene polymerization strategy calling coordinative chain transfer polymerization(CCTP)[1].In such a system,all the polydienyl chains are capped withη1-allyl-Al moieties,which reveal greater reactivity with cyclic esters and epoxide compounds,providing an effective manner to prepare polydiene-polyester amphiphilic block copolymers.Inspired by such findings,we now show herein how such types of chain-ends react with isot-hiocyanate to demonstrate an efficient in-situ manner to access end-functionalized polydienes by using CCTP. 展开更多
关键词 properties. POLYMERIZATION NEODYMIUM
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Relationship Between Polyamine Metabolism in Roots and Salt Tolerance of Barley Seedlings 被引量:14
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作者 赵福庚 孙诚 +1 位作者 刘友良 章文华 《Acta Botanica Sinica》 CSCD 2003年第3期295-300,共6页
Plant growth rate (GR), contents of free polyamines (fPAs) and bound polyamines (bPAs) and activities of some key enzymes involved in polyamine (PA) metabolism in the roots of two barley (Hordeum valgare L.) cultivars... Plant growth rate (GR), contents of free polyamines (fPAs) and bound polyamines (bPAs) and activities of some key enzymes involved in polyamine (PA) metabolism in the roots of two barley (Hordeum valgare L.) cultivars differing in salt sensitivity were investigated with 0-300 mmol/L NaCl treatments. With 0-200 mmol/L NaCl treatments, activities of arginine decarboxylase (ADC) and transglutaminase (TGase) and PA oxidase (PAO) in the roots of barley seedlings all increased, while TGase and PAO activities decreased slightly at 300 mmol/L NaCl. As a result, free Put (fPut) content increased continuously with increasing concentrations of NaCl, while levels of free Spd (fSpd) and an unknown PA (fPAx) and bPAs (bPut, bSpd and bPAx), as well as (fSpd + fPAx)/fPut ratio rose at 50-200 mmol/L NaCl and reduced at 300 mmol/L NaCl. However, no significant change in the tetra-amine spermine (Spin) content was observed. Statistical analysis showed that GR was very significantly positively correlated with (fSpd + fPAx)/fPut ratios and the contents of bPAs, whereas a significant inverse correlation existed between GR and the ratios of fPA contents to bPA levels. These results showed that, under salt stress, the balance between fSpd, fPAx and fPut levels and an equipoise between fPA and bPA contents in roots were important to salt tolerance of barley seedlings. 展开更多
关键词 barley (Hordeum vulgare) polyamine (PA) METABOLISM salt tolerance
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Effect of surfactant Tween-80 on sulfur oxidation and expression of sulfur metabolism relevant genes of Acidithiobacillus ferrooxidans 被引量:9
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作者 彭安安 刘红昌 +1 位作者 聂珍媛 夏金兰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第12期3147-3155,共9页
The effects of surfactant Tween-80 on the growth, sulfur oxidation, and expression of selected typical sulfur metabolism relevant genes of Acidithiobacillus ferrooxidans ATCC 23270 were investigated. The results showe... The effects of surfactant Tween-80 on the growth, sulfur oxidation, and expression of selected typical sulfur metabolism relevant genes of Acidithiobacillus ferrooxidans ATCC 23270 were investigated. The results showed that in the presence of 10-2 g/L Tween-80, the growth of A. ferrooxidans and its metabolism on the insoluble substrate S0 and CuFeS2 were promoted. After 24 d of bioleaching, the copper extraction yield of chalcopyrite at 10-2 g/L Tween-80 increased by 16% compared with the bioleaching experiment without Tween-80. FT-IR spectra analysis revealed that the result was probably caused by the extracellular polymeric substances whose composition could be changed by the surfactant addition. RT-qPCR was used to analyze the differential expressions of 17 selected sulfur metabolism relevant genes in response to the addition of Tween-80. Down-regulation of the extracellular protein genes indicated the influence of Tween-80 on bacteria-sulfur adsorption. Variation of the expression level of the enzymes provided a supplement to sulfur metabolism investigation. 展开更多
关键词 Acidithiobacillus ferrooxidans sulfur metabolism surfactant Tween-80 RT-QPCR
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Electrochemical properties of nanocrystalline and amorphous Mg-Y-Ni alloys applied to Ni-MH battery 被引量:6
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作者 张羊换 韩忠刚 +3 位作者 袁泽明 杨泰 祁焱 赵栋梁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3736-3746,共11页
The as-cast Mg2Ni-type Mg20–xYxNi10 (x=0, 1, 2, 3 and 4) electrode alloys were prepared by vacuum induction melting. Subsequently, the as-cast alloys were mechanically milled in a planetary-type ball mill. The analys... The as-cast Mg2Ni-type Mg20–xYxNi10 (x=0, 1, 2, 3 and 4) electrode alloys were prepared by vacuum induction melting. Subsequently, the as-cast alloys were mechanically milled in a planetary-type ball mill. The analyses of scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM) reveal that nanocrystalline and amorphous structure can be obtained by mechanical milling, and the amount of amorphous phase increases with milling time prolonging. The electrochemical measurements show that the discharge capacity of Y0 alloy increases with milling time prolonging, while that of the Y-substituted alloys has a maximum value in the same condition. The cycle stabilities of the alloys decrease with milling time prolonging. The effect of milling time on the electrochemical kinetics of the alloys is related to Y content. Whenx=0, the high rate discharge ability, diffusion coefficient of hydrogen atom, limiting current density and charge transfer rate all increase with milling time prolonging, but the results are exactly opposite whenx=3. 展开更多
关键词 hydrogen storage Mg2Ni-type alloy mechanical milling element substitution electrochemical performance
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Overview of Pharmaceutical Research on Passiflora foetida L. 被引量:1
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作者 张月 张小伟 +6 位作者 司珂瑜 胡家华 宇磊 陈洪卫 李洪珠 巩江 倪士峰 《Agricultural Science & Technology》 CAS 2014年第7期1113-1116,共4页
Based on extensive literature search,the composition,pharmacology,clini cal applications of Passiflora foetida L,ecological characteristics were summarized with the aim to provide scientific data for further research ... Based on extensive literature search,the composition,pharmacology,clini cal applications of Passiflora foetida L,ecological characteristics were summarized with the aim to provide scientific data for further research and exploitation. 展开更多
关键词 Passiflora foetida L. COMPOSITION PHARMACOLOGY Clinical applications Reprehensive dietary Ecological characteristics
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Participation of H_2O_2 in Enhancement of Cold Chilling by Salicylic Acid in Banana Seedlings 被引量:27
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作者 康国章 王正询 孙谷畴 《Acta Botanica Sinica》 CSCD 2003年第5期567-573,共7页
The possible physiological mechanism of enhancement of cold tolerance by salicylic acid (SA) in banana seedlings ( Musa acuminata cv. Williams 8188) was explored. Measurements of leakage electrolyte after 2 d of re... The possible physiological mechanism of enhancement of cold tolerance by salicylic acid (SA) in banana seedlings ( Musa acuminata cv. Williams 8188) was explored. Measurements of leakage electrolyte after 2 d of recovery at 30/22 ℃ (day/night) following 3 d of cold stress at 7 ℃ showed that pretreatment with hydroponic solution containing SA 0.3-0.9 mmol/L as foliar spray under normal growth conditions (30/22 ℃) could significantly enhance cold tolerance of banana plants. The highest enhancing effect of SA occurred at 0.5 mmol/L and it showed the lowest leakage rate of electrolyte or smaller leaf wilting area after 2 d of recovery at normal temperature from 3 d of 7 ℃ or 5 ℃ cold stress. Higher concentrations (≥2.5 mmol/L) of SA, however, caused more electrolyte leakage, indicating that they aggravated chilling damage. Enhanced cold tolerance by SA could be related to H 2O 2 metabolism. Compared with water_treated seedlings (control), SA 0.5 mmol/L treatment inhibited activities of catalase (CAT) and ascorbate peroxidase (APX), increased peroxidase (POX) activity, but did not affect the activity of superoxide dismutase (SOD) under normal growth conditions, and these changes might lead to an accumulation of H 2O 2, whereas SA pretreatment enhanced the activities of CAT and APX, and reduced the increase in productions of H 2O 2 and thiobarbituric acid_reaction substances (TBARS) during subsequent 7 ℃ cold stress and recovery periods. Exogenous H 2O 2 treatments (1.5 -2.5 mmol/L) also increased cold tolerance of banana seedlings. Furthermore, pretreatment of banana seedlings with dimethylthiourea (a trap for H 2O 2) significantly inhibited cold tolerance induced by SA. These results suggested that endogenous H 2O 2 may be required for SA_enhanced cold tolerance. The significance of the interaction of SA, H 2O 2 and H 2O 2_metabolizing enzymes during cold stress has been discussed. 展开更多
关键词 salicylic acid banana ( Musa acuminata cv. Williams 8188) cold stress antioxidant enzyme activities cold tolerance H 2O 2 metabolism
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Metabolic Characteristics and Functional Diversity of Carbon Source in Microflora of Ponds with Recirculating Aquaculture System 被引量:2
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作者 李谷 宋景华 +3 位作者 李晓莉 张世羊 陶玲 张春雪 《Agricultural Science & Technology》 CAS 2014年第2期278-282,299,共6页
With Biolog Eco microplate, metabolic characteristics and functional diver-sity of carbon source in microflora of ponds were researched based on recitculating ponds and control ponds in order to explore effects of eco... With Biolog Eco microplate, metabolic characteristics and functional diver-sity of carbon source in microflora of ponds were researched based on recitculating ponds and control ponds in order to explore effects of eco-adjustments on microflo-ra in ponds. The results indicate that total number of bacterium, microbial metabolism activity, and diversity index in P7, P8, P1 and P2 kept higher, fol owed by P3, P4, P5 and P6. The utilization rate of microbes on sugars achieved the highest (31.0%-48.7%), fol owed by carboxylic acid (13.4%-18.0%), amino acid (10.1%-20.5%), polymers (9.4%-17.0%), biopolymer (5.7%-9.7%) and phenol (4.95%-7.50%). Principal component analysis divided microflora in different ponds, suggesting that microbial community has varied carbon source characteristics and nitrogen-containing compound and biopolymer metabolisms are most affected. 展开更多
关键词 Aquaculture pond MICROBE -Metabolic characteristics of carbon source Functional diversity
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“倒灶”、“倒楣”的文化考释 被引量:6
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作者 蔡正学 石金兰 《辞书研究》 2005年第2期193-195,共3页
关键词 “倒灶” “倒楣” 陇右方言 文化考释 武威话 代性名词 释义
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Variation of Agronomic Characters of F_2 of Predominance Cotton Combination and Its Utilization Evaluation 被引量:2
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作者 刘朝辉 董顺文 +1 位作者 熊鹰 何洪波 《Agricultural Science & Technology》 CAS 2007年第3期38-41,共4页
The agronomic property of elite cotton hybrid F2 was studied and the results showed that each investigated trait showed consecutive normal distribution except micronaire,so they were typically quantitative characters ... The agronomic property of elite cotton hybrid F2 was studied and the results showed that each investigated trait showed consecutive normal distribution except micronaire,so they were typically quantitative characters controlled by micro-effect polygene.Heterosis analysis indicated that the inbreeding depression of F2 generation was significant,and the heterosis was less than F1 in yield and its component traits,but the yield of F2 generation was prior to the control.Heterosis of most fiber property was very low,some of which were negatively significant.The entire variations indicated that the segregation of fiber property trait was objective and abundant in F2 population. 展开更多
关键词 Upland cotton HETEROSIS F2 generation
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Indices Related to the Resistance of Yuluxiang Pear to Stresses 被引量:1
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作者 杨盛 白牡丹 +2 位作者 高鹏 郝国伟 郭黄萍 《Agricultural Science & Technology》 CAS 2017年第6期961-964,992,共5页
To clarify the mechanism for slowing down vegetative growth to reduce withered floral buds occurring in Yuluxiang pear, the length and diameter of the new shoots, the activities of antioxidant enzymes and malondialdeh... To clarify the mechanism for slowing down vegetative growth to reduce withered floral buds occurring in Yuluxiang pear, the length and diameter of the new shoots, the activities of antioxidant enzymes and malondialdehyde (MDA) content in terminal buds of short shoots in a withered bud-occurring orchard in Wei County, Hebei Province and a normal bud-growing orchard of Wei County, and a normal bud-growing orchard in Taigu County, Shanxi Province were measured and com- pared. The results showed that the increases in the length and diameter of new shoots in the withered bud-occurring orchard were very significantly higher than those in the two normal bud-growing orchards, and the shoots in the withered bud- occurring orchard stopped growing later than in the two normal bud-growing or- chards. During the period of floral bud differentiation, the activities of superoxide dis- mutase (SOD), catalase (CAT), peroxidase (POD) and the content of MDA in the two normal bud-growing orchards all increased at first and decreased subsequently. But in the withered bud-occurring orchard, the activities of both SOD and POD gradually decreased during the period of floral bud differentiation, while the activity of CAT and the content of MDA increased at first and decreased subsequently. Withered floral buds had significantly lower activities of SOD, CAT and POD, but significantly higher content of MDA than normal buds. The results suggested that vigorous vegetative growth may lead to the occurrence of withered floral buds in Yuluxiang pear; in addition, the occurrence of withered floral buds in Yuluxiang pear may also be associated with the activities of SOD, CAT and POD. 展开更多
关键词 Yuluxiang pear Withered bud Reactive oxygen metabolism
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Prediction of Subcellular Localization of Eukaryotic Proteins Using Position-Specific Profiles and Neural Network with Weighted Inputs 被引量:3
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作者 邹凌云 王正志 黄教民 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第12期1080-1087,共8页
Subcellular location is one of the key biological characteristics of proteins. Position-specific profiles (PSP) have been introduced as important characteristics of proteins in this article. In this study, to obtain... Subcellular location is one of the key biological characteristics of proteins. Position-specific profiles (PSP) have been introduced as important characteristics of proteins in this article. In this study, to obtain position-specific profiles, the Position Specific lterative-Basic Local Alignment Search Tool (PSI-BLAST) has been used to search for protein sequences in a database. Position-specific scoring matrices are extracted from the profiles as one class of characteristics. Four-part amino acid compositions and lst-7th order dipeptide compositions have also been calculated as the other two classes of characteristics. Therefore, twelve characteristic vectors are extracted from each of the protein sequences. Next, the characteristic vectors are weighed by a simple weighing function and inputted into a BP neural network predictor named PSP-Weighted Neural Network (PSP-WNN). The Levenberg-Marquardt algorithm is employed to adjust the weight matrices and thresholds during the network training instead of the error back propagation algorithm. With a jackknife test on the RH2427 dataset, PSP-WNN has achieved a higher overall prediction accuracy of 88.4% rather than the prediction results by the general BP neural network, Markov model, and fuzzy k-nearest neighbors algorithm on this dataset. In addition, the prediction performance of PSP-WNN has been evaluated with a five-fold cross validation test on the PK7579 dataset and the prediction results have been consistently better than those of the previous method on the basis of several support vector machines, using compositions of both amino acids and amino acid pairs. These results indicate that PSP-WNN is a powerful tool for subcellular localization prediction. At the end of the article, influences on prediction accuracy using different weighting proportions among three characteristic vector categories have been discussed. An appropriate proportion is considered by increasing the prediction accuracy. 展开更多
关键词 subcellular localization PSI-BLAST position-specific scoring matrices weighting function BP neural network
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