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Novel Kinetic Method for Expressing the Ability of Antioxidant to Scavenge Radicals

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Chemical Research in Chinese Universities 2013年第5期29卷 947-951页

作者： li yan-feng li Pei-ze liu zai-qun Department of Organic Chemistry College of Chemistry Jilin University Changehun 130012 t~ R. China

A method was developed to treat the result from an antioxidant trapping radicals including 2,2＇-azinobis （3-ethylbenzothiazoline-6-sulfonate） cationic radieal（ABTS＋＇）, 2,2＇-diphenyl-l-picrylhydrazyl radical（DPPH）, and galvinoxyl radical. In the presence of a certain concentration of an antioxidant, the decrease of the concentration of a kind of radicals follows the second order exponential function with the increase of the reaction time（t）, v＆., [radical]=Ae-t/a＋Be rib＋c, the derivation operation of which obtains the differential style, -d[radical]/dt= （A/a）e t/a＋（B/b）e-t/b, revealing the relationship between the reaction rate（r=-d[radical]/dt） and the reaction time（t）. Thus, the reaction rate at the beginning of the reaction@0） can be calculated by assigning t=-0 in the equation of -d[radical]/dt-t. Based on the concept of the reaction rate, r=k[radical][antioxidant], the rate constant（k） can be calculated based on r0 and the initial concentrations of radical and antioxidant, k=-r0/（[radieal]o[antioxidant]0）. The k means the rate of a fresh antioxidant molecule to trap a fresh radical. This method was used to treat the interactions of ABTS＋＇, DPPH, and galvinoxyl radicals with three homoisoflavonoids, four pyrazoles, and three ferrocenyl Schiff bases. It was found that ferrocenyl group is beneficial for antioxidants to reduce ABTS＋＇, and ortho-hydroxyl group is beneficial for antioxidants to donate hydrogen atom in phenolic hydroxyl group to DPPH and galvinoxyl radicals.

关键词： Rate constant Radical-scavenging ability Antioxidant capacity Chemical kinetics

Identification of leaf rust resistance genes in common wheat varieties from China and foreign countries

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Journal of Integrative Agriculture 2021年第5期20卷 1302-1313页

作者： liu Yuan Takele Weldu GEBREWAHID ZHANG Pei-pei li zai-feng liu Da-qun College of Plant Protection Hebei Agricultural UniversityBaoding 071001P.R.China College of Agriculture Aksum UniversityShire-Indaslassie 314Ethiopia

Wheat leaf rust,triggered by Puccinia triticina Eriks(Pt),is among the most important diseases of wheat *** resistant varieties against leaf rust is the most effective,environmentally-friendly and economic way to control the *** the present study,66 wheat varieties form China and foreign countries were tested with 17 Pt races for gene postulation during the seedling stage in the *** the varieties were also planted to identify slow rusting responses to leaf rust at the adult plant stage in Baoding and Zhoukou field trials during the 2016/2017 to 2017/2018 cropping ***,12 closely linked molecular markers to known leaf rust resistance(Lr)genes were used for assessing all the *** results of both gene postulation and molecular marker identification showed that a total of eight Lr genes,Lr1,Lr10,Lr17,Lr20,Lr26,Lr34,Lr37 and Lr46,either singly or in combination were detected in 32 *** Lr genes were not identified in the remaining 34 *** varieties were found to have slow rusting *** resistance sources identified in this study can be used as resources for resistance against leaf rust in wheat breeding programs in China and the respective foreign countries.

关键词： wheat gene postulation molecular marker Lr gene

Seedling and adult plant resistance to leaf rust in 46 Chinese bread wheat landraces and 39 wheat lines with known Lr genes

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Journal of Integrative Agriculture 2019年第5期18卷 1014-1023页

作者： ZHANG Pei-pei Takele Weldu Gebrewahid ZHOU Yue li Qing-luo li zai-feng liu Da-qun Department of Plant Pathology College of Plant Protection Hebei Agricultural University College of Agriculture Aksum University-Shire Campus College of Biochemistry and Environmental Engineering Baoding University

Wheat leaf rust,caused by Puccinia triticina(Pt),is an important foliar disease that has an important influence on wheat *** most economic,safe and effective way to control the disease is growing resistant *** the present study,a total of 46 wheat landraces and 34 wheat lines with known Lr(leaf rust resistance)genes were inoculated with 16Pt pathotypes for postulating seedling resistance gene(s)in the *** cultivars and five wheat differential lines with adult plant resistance(APR)genes(Lr12,Lr22b,Lr34,Lr35 and Lr37)were also evaluated for identification of slow rusting resistance in the field trials in Baoding,Hebei Province of China in the 2014–2015 and 2015–2016 cropping ***,10 functional molecular markers closely linked to 10 known Lr genes were used to detect all the wheat *** showed that most of the landraces were susceptible to most of the Pt pathotypes at seedling ***,Lr1 was detected only in *** field experimental test of the two environments showed that 38 landraces showed slow rusting *** cultivars possessed Lr34 but none of the landraces contained Lr37 and *** genes namely,Lr9,Lr19,Lr24,Lr28,Lr29,Lr47,Lr51 and Lr53 were effective at the whole plant ***18,Lr36 and Lr45 had lost resistance to part of pathotypes at the seedling stage but showed high resistance at the adult plant ***34 as a slowing rusting gene showed good resistance in the *** race-specific APR genes Lr12,Lr13,Lr35 and Lr37 conferred good resistance in the field *** race-specific genes,Lr2b,Lr2c,Lr11,Lr16,Lr26,Lr33 and LrB had lost *** 38 landraces showed slow rusting resistance to wheat leaf rust can be used as resistance resources for wheat resistance breeding in China.

关键词： Triticum aestivum L. wheat leaf rust gene postulation adult plant resistance

EFFECTS OF GELATION RETARDATION ON THERMAL RESPONSE BEHAVIOR OF PNIAPM GELS:A METHOD TO IMPROVE THEIR DESWELliNG KINETICS

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Chinese Journal of Polymer Science 2007年第6期25卷 635-640页

作者： qun-feng liu Si-dong li Ping Zhang yan-xun Lan Man-geng Lu College of Science Guangdong Ocean University Zhanjiang 524088 China Guangzhou Institute of Chemistry Chinese Academy of Sciences P.O. Box 1122 Guangzhou 510650 China

P（N-isopropylacrylamide）（PNIPAM） prepared by reversible addition fragmentation chain transfer （RAFT） polymerization exhibited gelation retardation. The intermediate before gelation was characterized and indicated the presence of branched or hyperbranched chains. The swelling behavior was investigated, and the gel by RAFT polymerization （RAFT gel） showed accelerated shrinking kinetics and higher swelling ratio comparing with conventional gels （CG）. The study was extended to gels prepared by using 2-hydroxy- 1-ethanethiol as chain transfer agent and by using low concentration solutions. The two systems also exhibited retardation effects and improved deswelling kinetics. The different swelling behaviors of these gels and CG could be attributed to the presence of dangling chains caused by gelation retardation.

关键词： Chain transfer Hyperbranched Graft Hydrogels.

Mapping of QTL conferring leaf rust resistance in Chinese wheat lines W014204 and Fuyu 3 at adult plant stage

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Journal of Integrative Agriculture 2016年第1期15卷 18-28页

作者： QI Ai-yong ZHANG Pei-pei ZHOU Yue YAO Zhan-jun li zai-feng liu Da-qun Department of Plant Pathology College of Plant Protection Agricultural University of Hebei Department of Biochemistry Baoding University College of Agronomy Agricultural University of Hebei

Wheat leaf rust is a destructive foliar disease of common wheat （Triticum aestivum L.） worldwide. The most effective, economical s to control the disease is growing resistant cultivars with adult plant resistance （APR）. The Chinese wheat tines W014204 and Fuyu 3 showed high leaf rust resistance in the field. To identify leaf rust APR genes in the two lines, two mapping populations with 215 and 163 F2：3 lines from the crosses W014204/Zhengzhou 5389 and Fuyu 3/Zhengzhou 5389, respectively, were phenotyped for leaf rust severities during the 2010-2011, 2011-2012 and 2012-2013 cropping seasons in the field at Baoding, Hebei Province, China. A total of 1 215 SSR markers were used to identify the quantitative trait loci （QTLs） for leaf rust APR in the two populations. In the W014204/Zhengzhou 5389 population, three QTLs were detected and designated as ***-lBL.1, ***-2BS.1 and ***-7DS, and explained 2.9-8.4, 11.5-38.3 and 8.5-44.5% of the phenotypic variance, respectively; all the resistance alleles at these loci were derived from W014204. In the Fuyu 3/Zhengzhou 5389 population, three QTLs, ***-lBL.2, ***-2BS.2 and ***-7BL, explained 12.0-19.2, 22.3-38.9 and 4.1-4.3% of the phenotypic variance, respectively, and all resistance alleles were contributed by Fuyu 3. Based on chromosome positions of closely linked markers, both ***-lBL. 1 and ***-lBL.2 are Lr46, and ***-7DS is Lr34. ***-7BL was mapped on chromosome 7BL near to Lr68 and they are likely the same gene. Based on chromosome positions, pedigree and field reactions, the two 2BS QTLs are different from all the known APR genes and are likely to be newAPR QTL for leaf rust. These QTLs and their closely linked markers are potentially useful for improving leaf rust resistance in wheat breeding.

关键词： Triticum aestivum Puccinia triticina APR SSR marker

Molecular mapping of leaf rust resistance genes in the wheat line Yu 356-9

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Journal of Integrative Agriculture 2015年第7期14卷 1223-1228页

作者： HAN liu-sha li zai-feng WANG Jia-zhen SHI ling-zhi ZHU lin li Xing liu Da-qun Syed J A Shah College of Plant Protection Agricultural University of Hebei Nuclear Institute for Food and Agricuture

The Chinese wheat line Yu 356-9 exhibits a high level of resistance to leaf rust. In order to decipher the genetic base of resistance in Yu 356-9, gene postulation, inheritance analyses, and chromosome linkage mapping were carried out. Gene postulation completed using 15 leaf rust pathotypes and 36 isogenic lines indicated that Yu 356-9 was resistant to all pathotypes tested. F1 and F2 plants from the cross Yu 356-9 （resistant）/Zhengzhou 5389 （susceptible） were tested with leaf rust pathotype ＂FHNQ＂ in the greenhouse. Results indicated a 3：1 segregation ratio, indicative of the presence of a single dominant leaf rust resistance gene in Yu 356-9 which was temporarily designated as LrYu. Bulk segregant analysis and molecular marker assays were used to map LrYu. Five simple sequence repeat （SSR） markers on chromosome 2BS were found closely linked to LrYu. Among these markers, Xwmc770 is the most closely linked, with a genetic distance of 5.7 cM.

关键词： wheat leaf rust resistance gene inheritance analyses molecular mapping

Risk factors and surgical outcomes for spontaneous rupture of BCLC stages A and B hepatocellular carcinoma: A case-control study

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World Journal of Gastroenterology 2014年第27期20卷 9121-9127页

作者： Jing li liang Huang Cai-feng liu Jie Cao Jian-Jun yan feng Xu Meng-Chao Wu Yi-qun yan Department of Hepatic Surgery Ⅰ Eastern Hepatobiliary Surgery Hospital Second Military Medical University

AIM: To investigate the risk factors and surgical outcomes for spontaneous rupture of Barcelona Clinic liver Cancer (BCLC) stages A and B hepatocellular carcinoma (HCC).

关键词： Hepatocellular carcinoma Rupture Risk factor Tumor location Surgical outcome

Discovery and Asymmetric Total Synthesis of Phlegmine A as a Selective Inhibitor of ASIC1a

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CCS Chemistry 2024年第10期6卷 2529-2536页

作者： zai-feng Yuan Fei liu Yu-Fei Ou Wen-yan li li-yan Peng Xiao-Nian li Qin-Shi Zhao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201 School of Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137 University of Chinese Academy of Sciences Beijing 10049

Phlegmine A(1),a novel type of Lycopodium alkaloid with a unique skeleton,was isolated from the rare and endangered herbal medicinal plant,Phlegmariurus *** methods and X-ray diffraction analysis were employed to unambiguously elucidate the structure of phlegmine A(1).Furthermore,we realized the asymmetric total synthesis of the natural product phlegmine A(1)in 18 linear steps from commercial ingredients,achieving a 1.3%overall *** intramolecular carbene cyclization,dimethyldioxirane(DMDO)enamine oxidation,and Stevens rearrangement were exploited to establish the sterically congested vicinal quaternary centers,and an epimerization/aldol condensation/deacetylation reaction was utilized for the rapid assembly of enone at the final *** our semisynthesis attempts,a novel transformation was developed to constructα-aminoketone from enamine ***,the synthetic sample obtained from this work enabled the successful verification of phlegmine A(1)as a new type of highly selective acidsensing ion channel 1a(ASIC1a)inhibitor,which also exerted an in vivo analgesic effect,rendering it a promising lead compound.

关键词： Lycopodium alkaloids phlegmine A total synthesis ASIC1a inhibitor analgesic

Laparoscopic management of gastric gastrointestinal stromal tumors: A retrospective 10-year single-center experience

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World Journal of Gastroenterology 2017年第19期23卷 3522-3529页

作者： Guan-qun liao Tao Chen Xiao-Long qi yan-feng Hu Hao liu Jiang Yu Guo-Xin li Department of General Surgery Nanfang Hospital Southern Medical University Department of General Surgery Foshan Hospital affiliated to Southern Medical University

AIM To determine the feasibility,safety,and oncological outcome of laparoscopic resection of gastric gastrointestinal stromal tumors(GISTs)based on favorable or unfavorable *** Our hospital database included 207 patients who underwent laparoscopic removal of gastric GISTs from January 2004 to September *** demographics,clinical presentation,surgery,histopathology,postoperative course,and oncological outcomes were reviewed and *** Gastric GIST in favorable locations was present in81/207(39.1%)cases,and in unfavorable locations in 126/207(60.9%)*** mean tumor size was 3.28±1.82 *** conversions occurred,and complete R0 resection was achieved in 207(100%)*** were three incidences of iatrogenic tumor *** feasibility and safety of laparoscopic surgery were comparable in both groups with no statistical difference between unfavorable and favorable location groups,respectively:for operative time:83.86±44.41 vs 80.77±36.46 min,P=0.627;conversion rate:0%vs 0%;estimated blood loss:27.74±45.2vs 29.59±41.18 m L,P=0.780;tumor rupture during surgery:0.90%vs 2.82%,P=0.322;or postoperative complications:3.74%vs 7.04%,P=*** follow-up period recurrence rate was 1.89%with no significant differences between the two groups(3.03%vs 0%,P=0.447).Overall 5-year survival rate was98.76%and survival rates were similar between the two groups:98.99%vs 98.39%,P=0.623(unfavorable vs favorable,respectively).CONCLUSION The laparoscopic approach for gastric GISTs is safe and feasible with well-accepted oncological surgical *** for laparoscopic resection should be selected according to the location and size of the *** treatment of gastric GISTs in unfavorable locations should not be restricted in gastrointestinal centers.

关键词： Laparoscopic Gastrointestinal stromal tumors Gastrectomy Minimally invasive surgery