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Gnetifolin L and O, Two Dimeric Stilbenes from Gnetum Montanum 被引量:1
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作者 Hao CHEN Mao LIN(Institute of Materia Medica. Chinese Academy of Medical Sciences. Peking Union Medical College. 1 Xian Nong Tan Street. Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第7期579-582,共4页
Two new dimeric stilbenes, named gnetifolin L and gnetifolin O, were isolated from the alcoholic extract of lianas of Gnetum montanum. Their structures were elucidated mainly on the basis of spectroscopic data includi... Two new dimeric stilbenes, named gnetifolin L and gnetifolin O, were isolated from the alcoholic extract of lianas of Gnetum montanum. Their structures were elucidated mainly on the basis of spectroscopic data including 2D-NMR studies on peracetate derivatives. 展开更多
关键词 Gnetum montanum lianas stilbenes gnetifolin l o
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A Study of the Comets with Large Perihelion Distances C/2019 L3(ATLAS)and C/2019 O3(Palomar)
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作者 Alberto S.Betzler 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第9期199-213,共15页
This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS... This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS have a typical and unusually high activity level,respectively,based on the Afρparameter corrected to phase angle zero at perihelion.The absolute magnitude of comets ATLAS and Palomar in the o-band is 4.71±0.05 and 4.16±0.02 respectively.The cometary activity of comets ATLAS and Palomar probably began at r>13 au before perihelion and will end at r>14 au after perihelion,which means that they could remain active until the second half of 2026.The nucleus of comet ATLAS has a minimum radius of 7.9 km,and the nucleus of comet Palomar could be a little larger.The c-o colors of the comets ATLAS and Palomar are redder and bluer,respectively,at perihelion than the solar twin YBP 1194.These comets showed a bluish trend in the coma color with decreasing heliocentric distance.Comet Palomar probably had two outbursts after its perihelion,each releasing about 10^(8)kg of dust.The slopes of the photometric profile of the comae of these comets were between 1and 1.5,indicating a steady state during the observation campaign. 展开更多
关键词 individual C/2019 l3(ATlAS) C/2019 o3(Palomar) techniques:photometric methods:data analysis
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Analysis of the effect of professional teaching staff construction in the training of low-level nurses in operating room 被引量:1
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作者 Chang-Xu Kan Yong-Chao He +2 位作者 Hong-Xu Ren Xiao-Yu Liu Liang-Chen Sun 《Nursing Communications》 2022年第1期52-56,共5页
Objective:To explore the application effect of constructing professional teaching staff in low-level training in operating room,so as to further optimize the teaching strength of operating room in our hospital and imp... Objective:To explore the application effect of constructing professional teaching staff in low-level training in operating room,so as to further optimize the teaching strength of operating room in our hospital and improve the training effect of junior nurses.Methods:Thirty-eight low-level nurses in the operating room of a third-class hospital in Yantai were selected for half a year's nurse training.With theoretical scores,overall nursing performance,nurses'self-awareness evaluation system and nurses'satisfaction with tutors as evaluation criteria,and based on the selection of high-quality teachers,various evaluation indexes before and after the training of low-level nurses in the operating room were compared and evaluated through the cultivation of practical teaching teachers'ability and the application of a series of teaching methods based on the change of c ompetence-based education(CBE)teaching mode,the application of guided learning interactive canadian education(BOPPPS)teaching model and p roblem-b ased l earning(PBL)teaching method.Results:After the training,the examination scores of low-level nurses were significantly improved(P<0.05),the teaching quality was highly recognized by low-level nurses,the quality of low-level nurses was improved,and patients'satisfaction with nurses was improved.Conclusion:It is of great significance to assist the construction of professional teachers in evidence-based medicine.Through the training of practical teaching teachers'ability and the application of a series of teaching methods based on the change of CBE teaching model,the application of BOPPPS teaching model and PBL teaching method,the training results of nurses have been significantly improved and improved,which is worthy of clinical reference and promotion. 展开更多
关键词 t raining of-level nurses c onstruction of teachers o perating room c ompetence-based education guided learning interactive canadian education p roblem-b ased l earning
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Petrographic and Geochemical Characteristics of the Pouni Palaeoproterozoic Formations North of the Léo Square Degree (Burkina Faso, West Africa)
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作者 Adama Ouédraogo Yaméogo Pascal Ouiya +4 位作者 Hubert Gounwendmanaghré Zongo Omar Akonyiré Abraham Seydoux Traoré Saga Sawadogo Séta Naba 《Open Journal of Geology》 CAS 2024年第1期126-141,共16页
The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozo... The Pouni area is made up of basalts belonging to the Boromo belt, lamprophyres and granitoids. These geological formations are similar to geological formations of the same type in other regions of the Palaeoproterozoic domain of the Man/Leo shield. This study, which focused on the petrographic and geochemical characteristics of these geological formations, led to the following main conclusions: The lamprophyres are basic plutonic rocks that cut through other geological formations. The basalt belongs to the northern part of the Borormo belt and is thought to be a relic of overthickened oceanic plateaus. There are two groups of granitoid rocks. The granodiorite has a geochemical signature close to that of Archean TTGs and is metaluminous in character. It has a low potassium content. The minor element and rare earth element spectra indicate that it could be derived from partial melting of basic magmatic rocks. Biotite granites are peraluminous and highly potassic. Minor element contents and rare earth spectra indicate that they could be derived from partial melting of felsic materials. Geotectonic diagrams show that the granitoids identified in the Pouni zone were emplaced in an active tectonic context, similar to that of present-day subduction zones. 展开更多
关键词 Burkina Faso Dori Man/léo Shield PETRoGRAPHY Geochemistry Partial Melting Geotectonic Context
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Genetic Diversity Analysis of Wild Tea Plants in Yunnan Province Using EST-SSR Markers 被引量:4
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作者 Meng ZHOU Youyong LI +5 位作者 Xuemei SUN Jiajin WANG Jin XIE Hao CHENG Yungang WANG Benying LIU 《Agricultural Biotechnology》 CAS 2015年第1期9-15,共7页
In this study, 27 pairs of EST-SSR primers were employed to analyze the genetic diversity and genetic relationship of 100 wild tea plant germplasm re- sources and 22 cultivars, according to the results, a total of 88 ... In this study, 27 pairs of EST-SSR primers were employed to analyze the genetic diversity and genetic relationship of 100 wild tea plant germplasm re- sources and 22 cultivars, according to the results, a total of 88 polymorphic bands were amplified with 27 pairs of primers; the variation of effective alleles accounted for 69.01% ; a total of 183 genotypes were detected, with a variation range of 4 -11 ; averagely 6.78 genotypes were amplified with each primer pair; Shannon index (I) of 27 primer pairs ranged from 0.32 to I. 35, with an average of 0.88 ; the observed heterozygosity (0.52) was basically consistent with the expected het- erozygosity (0.52) ; the average polymorphism heterozygosity was 0.48, which was very close to 0.50 ; the average Nei's index was 0.51, which was higher than 0. 50 ; the average polymorphism information content (PIC) was 0.52, which was higher than 0.50, indicating high genetic diversity among wild tea germplasm resources in Yuunan Province. According to the clustering results, based on geographical origins and genetic backgrounds, 122 materials were clustered into 14 categories. Dendrogram based on Nei's genetic distance revealed complex genetic relationships among wild tea germplasm resources in Yunnan Province. This study provided certain reference for subsequent preservation, development and research of wild tea germplasm resources in China. 展开更多
关键词 Tea plant[ Camellia sinensis l.) o. Kuntze] EST-SSR Genetic diversity Genetic relationship
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Response of nitrogen mineralization dynamics and biochemical properties to litter amendments to soils of a poplar plantation 被引量:2
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作者 Xiaomin Ge Shiping Deng +4 位作者 Ling Zhu Yong Li Zhiyuan Jia Ye Tian Luozhong Tang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第4期913-922,共10页
Understanding the impact of plant litters on soil nitrogen (N) dynamics could facilitate development of management strategies that promote plantation ecosystem function. Our objective was to evaluate the effects of ... Understanding the impact of plant litters on soil nitrogen (N) dynamics could facilitate development of management strategies that promote plantation ecosystem function. Our objective was to evaluate the effects of different litter types on N mineralization and availability, microbial biomass, and activities of L-asparaginase and odiphenol oxidase (o-DPO) in soils of a poplar (Populus deltoides) plantation through 24 weeks of incubation experiments. The tested litters included foliage (F), branch (B), or root (R) of poplar trees, and understory vegetation (U) or a mixture of F, B, and U (M). Litter amendments led to rapid N immobilization during the first 4 weeks of incubation, while net N mineralization was detected in all tested soils from 6 to 24 weeks of incubation, with zero-order reaction rate constants (k) ranging from 7.7 to 9.6 mg N released kg-1 soil wk-1. Moreover, litter addition led to increased (C) 49-128% and increased microbial biomass carbon MBC:MBN ratio by 5-92%, strengthened activities of L-aspaxaginase and o-DPO by 14-74%; Up to about 37 kg N ha-1 net increase in mineralized N in litter added soils during 24 weeks of incubation suggests that adequate poplar and understory litter management could lead to reduced inputs while facilitate sustainable and economic viable plantation production. 展开更多
关键词 Plant litter Nitrogen mineralization Soilmicrobial biomass l-ASPARAGINASE o-diphenol oxidase
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HETERONUCLEAR COMPLEX CONTAINING COPPER-LANTHANIDE ARRAYS: THE SYNTHESIS AND CRYSTAL STRUCTURE OF Ln_2Cu_4L_8 (HL)_4(OH)_2(CIO_4)_4(H_2O)_(10)·2CH_3COCH_3 (Ln = Tb (1), Y (2); HL = 2-Pyridone C_5H_5NO)
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作者 Hong Ye SUN Ming Jie ZHANG +3 位作者 Chun Hui HUANG Guang Xian XU Zhong Sheng JIN Shong Chun JIN Research Center of Rare Earth Chemistry, Peking University, Beijing 100871, China Changchun Institute of Applied Chemistry, Academia Sinica Changchun 130022, China 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第7期649-652,共4页
Reaction of 2-pyridone, copper acetate and terbium(or yttrium) perchlorate in acetone with the mole ratio 6: 2: 1 results in the formation of heteronuclear complex Ln_2Cu_4L_8 (HL)_4 (OH)_2 (ClO_4)_4 (H_20)_(10) 2CH_3... Reaction of 2-pyridone, copper acetate and terbium(or yttrium) perchlorate in acetone with the mole ratio 6: 2: 1 results in the formation of heteronuclear complex Ln_2Cu_4L_8 (HL)_4 (OH)_2 (ClO_4)_4 (H_20)_(10) 2CH_3COCH_3(Ln = Tb (1), Y (2)). By recrystallizing (1) in CHCl_3 single crystals were obtained and the structure was determined by four-circle diffractometer. Data showed that the crystal is in space group C2/m with a=27. 454(9)A, b=13, 608A, c=30. 556(11)A, β=99. 89(3)°, v=11245. 7(7. 5)A^3. The structure was solved by a combination of Patterson method and Fourier technique. The final R value is 0. 103. In the structure, four copper and two terbium ions are bridged by 2-pyridone anions to form an essentially octahedral Cu_4Tb_2 core. The terbium atoms are each eight-coordinate and the copper atoms are five-coordinate. 展开更多
关键词 Cu oH CIo4 HETERoNUClEAR CoMPlEX CoNTAINING CoPPER-lANTHANIDE ARRAYS H2o lN THE SYNTHESIS AND CRYSTAl STRUCTURE oF ln2Cu4l8 TB Hl CH
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Effects of Different Cadmium Levels on Active Oxygen Metabolism and H_2O_2-Scavenging System in Brassica campestris L.ssp.chinensis
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作者 SUNGuang-wen ZHUZhu-jun FANGXue-zhi 《Agricultural Sciences in China》 CAS CSCD 2004年第4期305-309,共5页
The effects of different Cd (Cadmium) levels on generation of active oxygen speceies(AOS) and H2O2-scavenging system in the leaves of Brassica campestris L. ssp. chinensiswere studied. The results showed that generat... The effects of different Cd (Cadmium) levels on generation of active oxygen speceies(AOS) and H2O2-scavenging system in the leaves of Brassica campestris L. ssp. chinensiswere studied. The results showed that generation rate, and H2O2 content were enhancedand malondialdehyde (MDA) content increased with the increase of Cd concentrations inthe growth medium. The activities of ascorbate peroxidase (APX), dehydroascorbatereductase (DR) and glutathione reductase (GR) were promoted by the addition of Cd.Exposed to Cd also increased the contents of ascorbate (AsA) and glutathione (GSH) in theleaves. 展开更多
关键词 Brassica campestris l.ssp.chinensis Cadmium Active oxygen species Glutathione Ascorbate H2o2-scavenging enzymeso2_
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Isozyme analysis on progenes of somatic hybrids of Oryza sativa L.and O.officinalis
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作者 TENG Sheng HU Zhanghua ZHANG Xueqin and YAN Qiusheng,CNRRI,Hangzhou 310006,China 《Chinese Rice Research Newsletter》 1996年第2期6-6,共1页
Some wild species of Oryza possess agronomi-cally useful traits such as disease/insect resis-tance and salt tolerance.However,the use ofwild Oryza species for rice improvement hasbeen hampered by the sexual incompatib... Some wild species of Oryza possess agronomi-cally useful traits such as disease/insect resis-tance and salt tolerance.However,the use ofwild Oryza species for rice improvement hasbeen hampered by the sexual incompatibility orsterility of hybrids obtained by conventionalmethods.We have used protoplast fusion as amethod to incorporate useful trait of wild O-ryza species into cultivated rice and~ obtainedsomatic hybrid plants between O.sativa and 展开更多
关键词 In Isozyme analysis on progenes of somatic hybrids of oryza sativa l.and o.officinalis
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Effects of exogenous salicylic acid on growth and H_2O_2-metabolizing enzymes in rice seedlings under lead stress 被引量:30
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作者 CHEN Jing ZHU Cheng LI Li-ping SUN Zhong-yang PAN Xue-bo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第1期44-49,共6页
Salicylic acid (SA) was an essential component of the plant resistance to pathogens and also plays an important role in mediating plant response to some abiotic stress. The possible effects of SA on the growth and H... Salicylic acid (SA) was an essential component of the plant resistance to pathogens and also plays an important role in mediating plant response to some abiotic stress. The possible effects of SA on the growth and H2O2-metabolizing enzymes in rice seedlings under lead stress were studied. When rice seedlings grown in nutrient solution containing Pb^2+ (0, 0.05, 0.15, 0.25 mmol/L) for 18 d, the plant biomass as well as the chlorophyll content of leaves decreased with increasing Pb concentration. The pre-treatment with SA (treated with 0.1 mmol/L SA for 48 h before Pb stress) partially protected seedlings from Pb toxicity. The chlorophyll contents were significant higher in leaves of Pb-exposed with SA pre-treatment seedlings than in Pb-exposed plants at the same Pb intensity. SA pre-treated alone could significantly increase the length of shoot and root of seedlings but the vigour difference was not marked under long-term exposure to Pb toxicity. SA pre-treated influence the H2O2 level in leaves of seedlings by up-regulating the activity of superoxide dismutase (SOD), repressing the activity of catalase (CAT) and ascorbate peroxidase (APX) depending on the concentrations of Pb^2+ in the growth medium. The results supported the conclusion that SA played a positive role in rice seedlings against Pb toxicity. 展开更多
关键词 ascorbate peroxidase CATAlASE H2o2 lead stress rice oryza sativa l.) salicylic acid superoxide dismutase
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Genotypic Analysis of Heading Time on an Indica Rice Cultivar,Nanjing 11 被引量:1
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作者 LUO Lin-guang, SU Chang-chao, Eiji Shimura, ZHAI Hu-qu and WAN Jian-min( State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095 ) 《Agricultural Sciences in China》 CAS CSCD 2002年第1期19-24,共6页
In this paper, the genotype of heading time in Nanjing 11, an indica variety, was analyzed by crossing with tester varieties, Akihikari (e1e1e2e2e3e3SeleSele), Koshihikari (E1E1E2E2 e3e3 SeleSele), Nipponbare(E1E1e2e2... In this paper, the genotype of heading time in Nanjing 11, an indica variety, was analyzed by crossing with tester varieties, Akihikari (e1e1e2e2e3e3SeleSele), Koshihikari (E1E1E2E2 e3e3 SeleSele), Nipponbare(E1E1e2e2e3e3Se1Se1 )and HinohikarKEjE^ E2E2 e3e3 SelSel), of which the genotypes of heading time were well known. The results showed genotype of heading time in Nanjing 11 was E1E1 e2e2 E3E3 SelSel and also included a recessive inhibitor i-Sel for photoperiod-sensitivity as well. Meanwhile, the two photoperiod-sensitive genes, E1 and Sel, in Nanjing 11 were also identified by crossing with QTL nearly isogenic lines of Nipponbare, NIL(Hdl )and NIL(Hd4)which have complementary effects. 展开更多
关键词 o. Saliva l. Nanjing 11 Heading time Photoperiod-sensitivity Genotype
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Synthesis,Characterization and Antibacterial Properties of Rare Earth (Ce^(3+) ,Pr^(3+) ,Nd^(3+) ,Sm^(3+) ,Er^(3+) ) Complexes with L-Aspartic Acid and o-Phenanthroline 被引量:15
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作者 郁慧 何其庄 +1 位作者 杨静 郑文捷 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期4-8,共5页
Five novel ternary complexes of rare earth ions with L-Aspartic acid (Asp) and o-phenanthroline (Phen) were synthesized in ethanol aqueous solution. Their compositions were characterized by elemental analysis, molar c... Five novel ternary complexes of rare earth ions with L-Aspartic acid (Asp) and o-phenanthroline (Phen) were synthesized in ethanol aqueous solution. Their compositions were characterized by elemental analysis, molar conductance, FT-IR, Raman, UV-VIS and TG-DTA. The compositions of the complexes were confirmed to be: RE( Asp)3PhenCl3·3H2O (RE: Ce3+ , Pr3+ , Nd3+ , Sm3+ , Er3+ ). The antibacterial activity test shows that all these complexes exhibit excellent antibacterial ability against Escherichia coli, Staphylococcus aureus and Candida albicans. The antimicrobial spectrum of the complexes are broad. 展开更多
关键词 CoMPlEXES o-PHENANTHRolINE l-Aspartic acid antibacterial activity rare earths
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A novel antimicrobial flavonoidic glycoside from the leaves of Alstonia macrophylla Wall ex A.DC(Apocynaceae) 被引量:3
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作者 Mehtab Parveen Zakia Khanam +1 位作者 Akhtar Ali Syed Mohmud Ahmad 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第5期593-595,共3页
A new flavonoidic glycoside,tricin-4’-O-β-L-arabinoside(1) was isolated from the leaves of Alstonia macrophylla along with two known flavonoids,vitexin and myricetin-3′-rhamnoside-3-O-galactoside.Their structures w... A new flavonoidic glycoside,tricin-4’-O-β-L-arabinoside(1) was isolated from the leaves of Alstonia macrophylla along with two known flavonoids,vitexin and myricetin-3′-rhamnoside-3-O-galactoside.Their structures were established by chemical and spectral evidences.The known compounds were reported for the first time from this plant.Moreover compound 1 was tested for antifungal and antibacterial activities. 展开更多
关键词 Alstonia macrophylla VITEXIN Myricetin-3’-rhamnoside-3-o-galactoside Tricin-4′-o-β-l-arabinoside Antibacterial Antifungal activity
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Sensitivity Difference in the Extratropical Atmosphere to Two Types of El Nio Events 被引量:1
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作者 FU Jian-Jian ZHANG Ming-Hong +1 位作者 HAN Zhe LI Shuanglin 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第5期355-359,共5页
A comparison of sensitivity in extratropical circulation in the Northern Hemisphere (NH) and Southern Hemisphere (SH) is conducted through observational analyses and diagnostic linear model experiments for two typ... A comparison of sensitivity in extratropical circulation in the Northern Hemisphere (NH) and Southern Hemisphere (SH) is conducted through observational analyses and diagnostic linear model experiments for two types of El Ni(n)o events,the traditional El Ni(n)o with the strongest warmth in the eastern tropical Pacific (EP El Ni(n)o) and the El Ni(n)o Modoki with the strongest warmth in the central tropical Pacific (CP El Ni(n)o).It is shown that CP El Ni(n)o favors the occurrence of a negative-phase Northern Annular Mode (NAM),while EP El Ni(n)o favors that of the Pacific-North American (PNA) pattern.In SH,both EP and CP El Ni(n)o induce a negative phase Southern Annular Mode (SAM).However,the former has a greater amplitude,which is consistent with the stronger sea surface temperature (SST) warmth.The difference in the two types of El Ni(n)o events in NH may originate from the dependence of heating-induced extratropical response on the location of initial heating,which may be associated with activity of the stationary wave.In SH,the lack of sensitivity to the location of heating can be associated with weaker activity of the stationary wave therein. 展开更多
关键词 E(l Ni(n)o Modoki El Ni(n)o Northern Annular Mode Pacific-North American Southern Annular Mode
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Stereoselective Addition of Organotitanium and Grignard Reagents to 3,5-O-isopropylidene-L-glucurono-γ-lactone 被引量:5
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作者 Hong CHEN Shao Yi SUN and De Quan YU(Institute of Meteria Medica, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第10期889-892,共4页
Substituted PhMgX and PhTi(OCHMe2)4MgX react with 3,5-O-isopropylidene-L-glucurono-γ-lactone 4 to give tetrads 5a-e and its stereoisomers 6a-e Tetrads 5a-e are the important intermediates in the synthesis of howiinol... Substituted PhMgX and PhTi(OCHMe2)4MgX react with 3,5-O-isopropylidene-L-glucurono-γ-lactone 4 to give tetrads 5a-e and its stereoisomers 6a-e Tetrads 5a-e are the important intermediates in the synthesis of howiinol Al and its derivatives. The stereoselectivities of substituted PhTi(OCHMe2)4Mg (5a-e:6a-e ratio, 68-72:32-28) were better than those of substituted PhMgX(33-64:67-36) in the reaction. The effects of different substitUted groups and positions (p-Me, m-Me, o-MeO, p-Cl) of the phenyl ring on their stereoselectivies were not significant. 展开更多
关键词 organotitanium reagents Stereoselective reaction 3 5-o-isopropylidene-l-glucurono-γ-lactone
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Thermal Behavior and Lithium Ion Conductivity of L_2O-Al_2O_3-TiO_2-SiO_2-P_2O_5 Glass-ceramics 被引量:1
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作者 CHEN Hongping TAO Haizheng +1 位作者 WU Qide ZHAO Xiujian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第1期67-72,共6页
A lithium ion conductive solid electrolyte, L20-AI203-TiO2-SiO2-P20s glass with NASICON- type structure have been synthesized and transformed into glass-ceramic through thermal-treatment at various temperatures from 7... A lithium ion conductive solid electrolyte, L20-AI203-TiO2-SiO2-P20s glass with NASICON- type structure have been synthesized and transformed into glass-ceramic through thermal-treatment at various temperatures from 700 to 1 000 ~C for 12 h. The differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and complex impedance techniques were employed to characterize the samples. The experimental results indicated that the capability of glass forming in this system is superior to that of L20-A1203-TiO2-PzO~. The glass has an amorphous structure and resultant glass-ceramic mainly consisting of LiTi2(PO4)3 phases. Impurity phases AIPO4, TiO2, TiP207 and unidentified phase were observed. With the enhanced heat-treatment temperature, grain grew gradually and lithium ion conductivity of glass-ceramics increased accordingly, the related impedance semicircles were depressed gradually and even disappeared, which could be analytically explained by the coordinate action of the 'Constant phase element' (CPE) model and the 'Concept of Mismatch and Relaxation' model (CMR). When the sample is devitrified at 1 000 ~C, the maximum room temperature lithium ion conductivity comes up to 4.1 x 10-4 S/cm, which is suitable for the application as an electrolyte of all-solid-state lithium batteries. 展开更多
关键词 inorganic solid electrolyte GlASS-CERAMIC l2o-A12o3-Tio2-Sio2-P2o5 system liTi2(Po4)3phase
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Synthesis, Characterization and Antibacterial Properties of Rare Earth Complexes with L-Phenylalanine and o-Phenanthroline 被引量:1
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作者 Yang Jing He Qizhuang Yu Hui Feng Jie Sun Jianjian 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第1期124-124,共1页
New solid ternary complexes of rare earth with L-Phenylalanine ( L-Phe ) and o-Phenanthroline (Phen) were synthesized in ethyl alcohol solution. Their composition were characterized by elemental analysis, molar co... New solid ternary complexes of rare earth with L-Phenylalanine ( L-Phe ) and o-Phenanthroline (Phen) were synthesized in ethyl alcohol solution. Their composition were characterized by elemental analysis, molar conductance, IR, Raman, UV-VIS, TG-DTA. The compositions of the complexes were confirmed to be RE ( Phe )3Phen Cl3 · 3H2O ( RE = La^3+, Ce^3+, Pr^3+, Nd^3+, Sm^3+, Eu^3+, Er^3+, Y^3+). The antibacterial activities testing indicates that all these solid ternary complexes have antibacterial ability against Escherich coli, Staphy lococcus aureus, Candida albican (MIC are about 65 × 10^-4%, 15 × 10^-3%, 4 × 10^-2%, respectively). 展开更多
关键词 l-PHENYlAlANINE o-PHENANTHRolINE ternary complex rare earths
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Glyoxylic acid as catalyst:A simple selective synthesis of 1,2-disubstituted benzimidazoles in aqueous media 被引量:2
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作者 Shivaji S.Pawar Deepak V.Dekhane +1 位作者 Murlidhar S.Shingare Shivaji N.Thore 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第9期1055-1058,共4页
Glyoxylic acid (5 mol%) performs as a novel highly water-soluble catalyst for the synthesis of 2-aryl-l-arylmethyl-lH- benzimidazoles from a wide range of substituted o-phenylenediamines and various substituted alde... Glyoxylic acid (5 mol%) performs as a novel highly water-soluble catalyst for the synthesis of 2-aryl-l-arylmethyl-lH- benzimidazoles from a wide range of substituted o-phenylenediamines and various substituted aldehydes in good to excellent isolated yields (85-95%) using water as solvent at ambient temperature. The remarkable advantages offered by this method are easily and inexpensive available catalyst, simple procedure, mild conditions, much faster (20--40 rain) reactions and excellent yields of products. 展开更多
关键词 Glyoxylic acid BENZIMIDAZolES Aqueous media 2-Aryl-l-arylmethyl-lH-benzimidazoles o-Phenylenediamines and aldehydes
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Promoter methylation status of hMLH1,MGMT,and CDKN2A/p16 in colorectal adenomas 被引量:14
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作者 Vasiliki Psofaki Chryssoula Kalogera +4 位作者 Nikolaos Tzambouras Dimitrios Stephanou Epameinondas Tsianos Konstantin Seferiadis Georgios Kolios 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第28期3553-3560,共8页
AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma... AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/carcinoma.MGMT showed the highest frequency in each group.MGMT and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined loci.These findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal carcinogenesis.MSI and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis. 展开更多
关键词 Promoter methylation Microsatellite instability Human DNA mismatch repair gene mutator l homologue 1 o-6-methylguanine DNA methyltransferase Cyclin-dependent kinase inhibitor 2A
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Characterization of TaCOMT genes associated with stem lignin content in common wheat and development of a gene-specific marker 被引量:1
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作者 FU Lu-ping XIAO Yong-gui +5 位作者 YAN Jun LIU Jin-dong WEN Wei-e ZHANG Yong XIA Xian-chun HE Zhong-hu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第5期939-947,共9页
Stem lignin content(SLC) in common wheat(Triticum aestivum L.) contributes to lodging resistance. Caffeic acid 3-O-methyltransferase(COMT) is a key enzyme involved in lignin biosynthesis. Characterization of TaCOMT ge... Stem lignin content(SLC) in common wheat(Triticum aestivum L.) contributes to lodging resistance. Caffeic acid 3-O-methyltransferase(COMT) is a key enzyme involved in lignin biosynthesis. Characterization of TaCOMT genes and development of gene-specific markers could enable marker-assisted selection in wheat breeding. In the present study, the full-length genomic DNA(gDNA) sequences of TaCOMT genes located on chromosomes 3 A, 3 B, and 3 D were cloned by homologous cloning. Two allelic variants, TaCOMT-3 Ba and TaCOMT-3 Bb, were identified and differed by a 222-bp insertion/deletion(InDel) in the 3′-untranslated region(3′-UTR). A co-dominant gene-specific marker based on this InDel was developed and designated as Ta COMT-3 BM. A total of 157 wheat cultivars and advanced lines grown in four environments were used to validate the associations between allelic patterns and SLC. The SLC of cultivars with TaCOMT-3 Ba was significantly(P<0.01) higher than that of those with TaCOMT-3 Bb, and the marker TaCOMT-3 BM could be effectively used in wheat breeding. 展开更多
关键词 Triticum aestivum l. caffeic acid 3-o-methyltransferase STEM lignin content gene-specific MARKER loDGING resistance
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