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Understanding the Activity Performance of Comets 38P/Stephan-Oterma,64P/Swift-Gehrels and C/2017 M4(ATLAS)through Broadband Photometric Observations
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作者 Xuan Zhang Jin-Zhong Liu Le-Tian Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第8期147-156,共10页
In this work,we report observations of three comets:38P/Stephan-Oterma,64P/Swift-Gehrels,and C/2017 M4(ATLAS),conducted with the Nanshan one-meter wide-field telescope in 2018 August and November,and 2019January.We ex... In this work,we report observations of three comets:38P/Stephan-Oterma,64P/Swift-Gehrels,and C/2017 M4(ATLAS),conducted with the Nanshan one-meter wide-field telescope in 2018 August and November,and 2019January.We extracted morphological features through image enhancement techniques and calculated the dust activity parameter,Afρ,along with dust mass loss rates and coma color indices using broadband photometric data.Our morphological analysis uncovered a spectrum of dust characteristics among the observed comets,ranging from a significant twisted structure in comet 38P/Stephan-Oterma’s coma to the regular coma envelope surrounding comet 64P/Swift-Gehrels.The Afρvalues varied between 148.8±0.3 cm for 64P/Swift-Gehrels and1118.5±6.2 cm for C/2017 M4(ATLAS)(measured within a reference aperture radius ofρ=6″),indicating a range from moderate to high activity levels.Dust mass loss rates were estimated from 328.1 kg s^(-1)for comet 64P/Swift-Gehrels to 1395.5 kg s^(-1)for comet C/2017 M4(ATLAS).The color indices of comets 38P/Stephan-Oterma and C/2017 M4(ATLAS)closely resemble the average colors of active short-period comets and active longperiod comets,respectively.In contrast,64P/Swift-Gehrels exhibits a significantly bluer hue than typical Jupiter family comets. 展开更多
关键词 comets general-comets individual(38p/Stephan-Oterma 64p/Swift-Gehrels c/2017 M4(ATLAS))-techniques pHOTOMETRIc
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Simulating the Dynamics of Bimetallic Clusters Deposited onto a Surface Using Molecular Dynamics
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作者 Akbarali Rasulov Nodirbek Ibrokhimov +1 位作者 Jaxongir Khodjimatov Azamatjon Tukhtasinov 《Journal of Applied Mathematics and Physics》 2024年第8期2820-2828,共9页
This paper examines the interface development between a single crystalline Ag matrix and core-shell AgnCom nanoclusters that have been deposited with energies varying between 0.25 eV and 1.5 eV per atom using computer... This paper examines the interface development between a single crystalline Ag matrix and core-shell AgnCom nanoclusters that have been deposited with energies varying between 0.25 eV and 1.5 eV per atom using computer modeling techniques. Clusters undergo deformation as a result of the slowing down;they may also become epitaxial with the substrate and maintain their core-shell structure. A detailed analysis of the effects of the cluster-surface interaction is conducted over a realistic size and energy range, and a model is created to show how clusters accumulate. It is discovered that both the silver shells and the cobalt cluster cores exhibit limited epitaxy with the substrate, and that the contact produced is only a few atomic layers thick. The effect is higher for Ag shells than for Co cores, and it is not very energy dependent. 展开更多
关键词 cLUSTER Slowing Down LOW-ENERGY Molecular Dynamics Metrоpоlis Mоnte cаrlо Bi-Metallic
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Evidence of the Role of Carbon Vacancies in Nickel-Based Ohmic Contacts to n-Type Silicon Carbide 被引量:1
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作者 郭辉 张义门 张玉明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第1期5-9,共5页
N-wells are created by P+ ion implantation into Si-faced p-type 4H-SiC epilayer. Ti and Ni are deposited in sequence on the surface of the active regions. Ni2Si is identified as the dominant phase by X-ray diffracti... N-wells are created by P+ ion implantation into Si-faced p-type 4H-SiC epilayer. Ti and Ni are deposited in sequence on the surface of the active regions. Ni2Si is identified as the dominant phase by X-ray diffraction (XRD) analysis after metallization annealing. An amorphous C film at the Ni2 Si/SiC interface is confirmed by an X-ray energy-dispersive spectrometer (XEDS). The Ni2Si and amorphous C film are etched away selectively,followed by deposition of new metal films without annealing. Measurement of the current-voltage characteristics shows that the contacts are still ohmic after the Ni2 Si and amorphous C film are replaced by new metal films. The sheet resistance Rsh of the implanted layers decreases from 975 to 438f2/D, because carbon vacancies (Vc) appeared during annealing,which act as donors for electrons in SiC. 展开更多
关键词 NI ohmic contact silicon carbide carbon vacancies p^+ ion implantation
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Variation of the Mineral Elements in the Barks of Pinus armandii Infected by Cronartium ribicola
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作者 杨发忠 杨斌 +2 位作者 杨德强 朱海峰 何美军 《Plant Diseases and Pests》 CAS 2010年第1期14-17,共4页
[ Objective] The difference of mineral element content in healthy bark of P. armandii and bark affected by C. nbicola were compared, which would provide theoretical foundation for exploring new ways to control the dis... [ Objective] The difference of mineral element content in healthy bark of P. armandii and bark affected by C. nbicola were compared, which would provide theoretical foundation for exploring new ways to control the disease by artificial water and fertilizer. [ Method] Inductively Coupled Plasma Optical Emission Spectrometer( ICP-OES)was adopted to measure the variation of mineral elements content in bark after P. armandii was affected by C. nbicola. [Result] 45 mineral elements in the healthy bark and 46 mineral elements in affected bark caused by C. ribicola were detected. These mineral elements contained 14 kinds of mineral elements which were necessary for plant growth and 31 kinds of other mineral elements (32 kinds after affected disease). The total content of mineral elements in affected bark of P. armandii decreased for 15.77%, in which necessary elements for plant growth decreased for 15.54% and other elements decreased for 17.07%. The content of Ca decreased the most, decrease rate was about 75%. The order of content was also changed, they were Na 〉 Ca 〉 B 〉 K 〉 Si 〉 Mg 〉 S 〉 P in healthy bark, and Na 〉 B 〉 K 〉 Ca 〉 Mg 〉 P 〉 Si 〉 S in affected bark. [ Conclusion] The results laid foundation for controlling C. ribicola through application of mineral elements. 展开更多
关键词 p. armandii c. ribicola Mineral element Icp-OES
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Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings
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作者 Zhijuan Zhao Lina Wang +7 位作者 Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li Wanjie Zhang Chao Wang Junwen Wu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期90-102,共13页
To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,lig... To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings. 展开更多
关键词 pinus yunnanensis seedlings DROUGHT Non-structural carbohydrates c N p stoichiometric characteristics
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Effects of tree size and organ age on variations in carbon,nitrogen,and phosphorus stoichiometry in Pinus koraiensis
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作者 Yanjun Wang Guangze Jin Zhili Liu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期155-165,共11页
Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutr... Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global scales.However,our knowledge of how these nutrients vary with tree size,organ age,or root order at the individual level remains limited.We determined C,N,and P contents and their stoichiometric ratios(i.e.,nutrient traits)in needles,branches,and fine roots at different organ ages(0-3-year-old needles and branches)and root orders(1st-4th order roots)from 64 Pinus koraiensis of varying size(Diameter at breast height ranged from 0.3 to 100 cm)in northeast China.Soil factors were also measured.The results show that nutrient traits were regulated by tree size,organ age,or root order rather than soil factors.At a whole-plant level,nutrient traits decreased in needles and fine roots but increased in branches with tree size.At the organ level,age or root order had a negative effect on C,N,and P and a positive effect on stoichiometric ratios.Our results demonstrate that nutrient variations are closely related to organ-specific functions and ecophysiological processes at an individual level.It is suggested that the nutrient acquisition strategy by younger trees and organ fractions with higher nutrient content is for survival.Conversely,nutrient storage strategy in older trees and organ fractions are mainly for steady growth.Our results clarified the nutrient utilization strategies during tree and organ ontogeny and suggest that tree size and organ age or root order should be simultaneously considered to understand the complexities of nutrient variations. 展开更多
关键词 Tree size Organ age(or root order) carbon(c) Nitrogen(N) phosphorus(p) pinus koraiensis
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Anticancer therapeutic strategies for targeting mutant p53-Y220C
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作者 Vitaly Chasov Damir Davletshin +5 位作者 Elvina Gilyazova Regina Mirgayazova Anna Kudriaeva Raniya Khadiullina Youyong Yuan Emil Bulatov 《Journal of Biomedical Research》 CAS CSCD 2024年第3期222-232,共11页
The tumor suppressor p53 is a transcription factor with a powerful antitumor activity that is controlled by its negative regulator murine double minute 2(MDM2,also termed HDM2 in humans)through a feedback mechanism.At... The tumor suppressor p53 is a transcription factor with a powerful antitumor activity that is controlled by its negative regulator murine double minute 2(MDM2,also termed HDM2 in humans)through a feedback mechanism.At the same time,TP53 is the most frequently mutated gene in human cancers.Mutant p53 proteins lose wild-type p53 tumor suppression functions but acquire new oncogenic properties,among which are deregulating cell proliferation,increasing chemoresistance,disrupting tissue architecture,and promoting migration,invasion and metastasis as well as several other pro-oncogenic activities.The oncogenic p53 mutation Y220C creates an extended surface crevice in the DNA-binding domain destabilizing p53 and causing its denaturation and aggregation.This cavity accommodates stabilizing small molecules that have therapeutic values.The development of suitable small-molecule stabilizers is one of the therapeutic strategies for reactivating the Y220C mutant protein.In this review,we summarize approaches that target p53-Y220C,including reactivating this mutation with small molecules that bind Y220C to the hydrophobic pocket and developing immunotherapies as the goal for the near future,which target tumor cells that express the p53-Y220C neoantigen. 展开更多
关键词 p53 Y220c mutation small molecule DNA-binding domain IMMUNOtheRApY T cell receptor mimic antibody
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Effects of Vegetation Restoration Age on Soil C:N:P Stoichiometry in Yellow River Delta Coastal Wetland of China
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作者 CAO Qixue WANG Xiaojie +7 位作者 CHU Xiaojing ZHAO Mingliang WANG Lianjing SONG Weimin LI Peiguang ZHANG Xiaoshuai XU Shendong HAN Guangxuan 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1045-1059,共15页
Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this s... Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this study,we examined the re-sponses of soil C,N,and P contents and their stoichiometric ratios to vegetation restoration age,focusing on below-ground processes and their relationships to aboveground vegetation community characteristics.We conducted an analysis of temporal gradients based on the'space for time'method to synthesize the effects of restoration age on soil C:N:P stoichiometry in the Yellow River Delta wetland of China.The findings suggest that the combined effects of restoration age and soil depth create complex patterns of shifting soil C:N:P stoichiometry.Specifically,restoration age significantly increased all topsoil C:N:P stoichiometries,except for soil total phosphorus(TP)and the C:N ratio,and slightly affected subsoil C:N:P stoichiometry.The effects of restoration age on the soil C:N ratio was well constrained owing to the coupled relationship between soil organic carbon(SOC)and total nitrogen(TN)contents,while soil TP con-tent was closely related to changes in plant species diversity.Importantly,we found that the topsoil C:N:P stoichiometry was signific-antly affected by plant species diversity,whereas the subsoil C:N:P stoichiometry was more easily regulated by pH and electric con-ductivity(EC).Overall,this study shows that vegetation restoration age elevated SOC and N contents and alleviated N limitation,which is useful for further assessing soil C:N:P stoichiometry in coastal restoration wetlands. 展开更多
关键词 coastal wetland restoration age soil c:N:p stoichiometry soil properties plant species diversity Yellow River Delta of china
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化瘀散水煎剂通过调控miR-129-5p/FOXC1轴抑制肝癌裸鼠移植瘤生长 被引量:1
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作者 许丹 郑超 +2 位作者 余首德 严红梅 黄超群 《现代肿瘤医学》 CAS 2024年第6期1003-1009,共7页
目的:探讨化瘀散水煎剂通过调控微小RNA-129-5p/叉头框蛋白C1(FOXC1)轴对肝癌裸鼠移植瘤生长的影响。方法:建立肝癌裸鼠移植瘤模型,并分为裸鼠NC组、化瘀散水煎剂组、化瘀散水煎剂+inhibitor-NC组、化瘀散水煎剂+miR-129-5p inhibitor组... 目的:探讨化瘀散水煎剂通过调控微小RNA-129-5p/叉头框蛋白C1(FOXC1)轴对肝癌裸鼠移植瘤生长的影响。方法:建立肝癌裸鼠移植瘤模型,并分为裸鼠NC组、化瘀散水煎剂组、化瘀散水煎剂+inhibitor-NC组、化瘀散水煎剂+miR-129-5p inhibitor组,每组8只。qRT-PCR法检测miR-129-5p、FOXC1 mRNA表达水平,双荧光素酶报告基因实验验证miR-129-5p与FOXC1靶向调控关系,观察记录裸鼠的瘤重及移植瘤体积,HE染色观察移植瘤组织形态,TUNEL检测肿瘤组织细胞凋亡,免疫组织化学染色检测瘤组织Ki-67、Cleaved Caspase-3、FOXC1表达,Western blot检测Ki-67、Cleaved Caspase-3、FOXC1蛋白表达。结果:miR-129-5p在肝癌细胞中表达显著下降,FOXC1 mRNA表达显著升高,其中HepG2细胞变化最显著(P<0.05);双荧光素酶报告基因实验表明miR-129-5p与FOXC1存在靶向调控关系;与NC组相比,化瘀散水煎剂组肿瘤细胞出现坏死,凋亡数增加,miR-129-5p、Cleaved Caspase-3显著升高,移植瘤质量和体积、FOXC1、Ki-67表达显著降低(P<0.05);下调miR-129-5p逆转化瘀散水煎剂对肝癌移植瘤的抑制作用(P<0.05)。结论:化瘀散水煎剂可能通过上调miR-129-5p从而下调FOXC1表达,进而抑制肝癌移植瘤生长。 展开更多
关键词 肝癌 化瘀散水煎剂 微小RNA-129-5p 叉头框蛋白c1
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Degradation induces changes in the soil C:N:P stoichiometry of alpine steppe on the Tibetan Plateau 被引量:13
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作者 ZHANG Zhen-chao HOU Ge +2 位作者 LIU Miao WEI Tian-xing SUN Jian 《Journal of Mountain Science》 SCIE CSCD 2019年第10期2348-2360,共13页
Due to the Tibetan Plateau’s unique high altitude and low temperature climate conditions,the region’s alpine steppe ecosystem is highly fragile and is suffering from severe degradation under the stress of increasing... Due to the Tibetan Plateau’s unique high altitude and low temperature climate conditions,the region’s alpine steppe ecosystem is highly fragile and is suffering from severe degradation under the stress of increasing population,overgrazing,and climate change.The soil stoichiometry,a crucial part of ecological stoichiometry,provides a fundamental approach for understanding ecosystem processes by examining the relative proportions and balance of the three elements.Understanding the impact of degradation on the soil stoichiometry is vital for conservation and management in the alpine steppe on the Tibetan Plateau.This study aims to examine the response of soil stoichiometry to degradation and explore the underlying biotic and abiotic mechanisms in the alpine steppe.We conducted a field survey in a sequent degraded alpine steppe with seven levels inNorthern Tibet.The plant species,aboveground biomass,and physical and chemical soil properties such as the moisture content,temperature,pH,compactness,total carbon(C),total nitrogen(N),and total phosphorus(P)were measured and recorded.The results showed that the contents of soil C/N,C/P,and N/P consistently decreased along intensifying degradation gradients.Using regression analysis and a structural equation model(SEM),we found that the C/N,C/P,and N/P ratios were positively affected by the soil compactness,soil moisture content and species richness of graminoids but negatively affected by soil pH and the proportion of aboveground biomass of forbs.The soil temperature had a negative effect on the C/N ratio but showed positive effect on the C/P and N/P ratios.The current study shows that degradation-induced changes in abiotic and biotic conditions such as soil warming and drying,which accelerated the soil organic carbon mineralization,as well as the increase in the proportion of forbs,whichwere difficult to decompose and input less organic carbon into soil,resulted in the decreases in soil C/N,C/P,and N/P contents to a great extent.Our results provide a sound basis for sustainable conservation and management of the alpine steppe. 展开更多
关键词 Tibetan plateau ALpINE STEppE DEGRADATION Soil STOIcHIOMETRY c/N c/p N/p
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Zeolite P synthesis based on fly ash and its removal of Cu(Ⅱ) and Ni(Ⅱ) ions 被引量:7
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作者 Yong Liu Guodong Wang +3 位作者 Lu Wang Xianlong Li Qiong Luo Ping Na 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第2期341-348,共8页
Zeolite P was synthesized through hydrothermal method based on a kind of Class C fly ash(FA). X-ray diffraction(XRD), scanning electron microscopy(SEM), and Brunauer–Emmett–Teller(BET) were used to analyze and chara... Zeolite P was synthesized through hydrothermal method based on a kind of Class C fly ash(FA). X-ray diffraction(XRD), scanning electron microscopy(SEM), and Brunauer–Emmett–Teller(BET) were used to analyze and characterize the synthetic sample. The kinetics and thermodynamics of copper and nickel ions removed by the zeolite samples were experimentally explored in detail. The results of kinetic treatment showed the second-order exchange second-order saturation model(SESSM) can well describe the removal process of copper ions, while the first-order empirical kinetic model(FEKM) is the best kinetic model for nickel ions. Langmuir and Freundlich isotherms were used to fit the equilibrium concentration of Cu(Ⅱ) or Ni(Ⅱ) under certain conditions. Whether for copper or nickel ion, the Langmuir model is in good agreement with the experimental equilibrium concentration.The apparent theoretical removal capacities for Cu(Ⅱ) and Ni(Ⅱ) can reach to 138.1 mg·g^(-1) and 77.0 mg·g^(-1),respectively. 展开更多
关键词 class c FLY ASH ZEOLITE p Kinetics theRMODYNAMIcS
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Efficacy of tailored Helicobacter pylori eradication therapy based on antibiotic susceptibility and CYP2C19 genotype 被引量:29
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作者 Mitsushige Sugimoto Takahisa Furuta 《World Journal of Gastroenterology》 SCIE CAS 2014年第21期6400-6411,共12页
The cure rates of Helicobacter pylori (H. pylori) eradication therapy using a proton pump inhibitor (PPI) and antimicrobial agents such as amoxicillin, clarithromycin, and metronidazole are mainly influenced by bacter... The cure rates of Helicobacter pylori (H. pylori) eradication therapy using a proton pump inhibitor (PPI) and antimicrobial agents such as amoxicillin, clarithromycin, and metronidazole are mainly influenced by bacterial susceptibility to antimicrobial agents and the magnitude of the inhibition of acid secretion. Annual cure rates have gradually decreased because of the increased prevalence of H. pylori strains resistant to antimicrobial agents, especially to clarithromycin. Alternative regimens have therefore been developed incorporating different antimicrobial agents. Further, standard PPI therapy (twice-daily dosing) often fails to induce a long-term increase in intragastric pH &#x0003e; 4.0. Increasing the eradication rate requires more frequent and higher doses of PPIs. Therapeutic efficacy related to acid secretion is influenced by genetic factors such as variants of the genes encoding drug-metabolizing enzymes (e.g., cytochrome P450 2C19, CYP2C19), drug transporters (e.g., multidrug resistance protein-1; ABCB1), and inflammatory cytokines (e.g., interleukin-1&#x003b2;). For example, quadruple daily administration of PPI therapy potently inhibits acid secretion within 24 h, irrespective of CYP2C19 genotype. Therefore, tailored H. pylori eradication regimens that address acid secretion and employ optimal antimicrobial agents based on results of antimicrobial agent-susceptibility testing may prove effective in attaining higher eradication rates. 展开更多
关键词 Helicobacter pylori Tailored eradication therapy proton pomp inhibitor cytochrome p450 2c19 cLARITHROMYcIN
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Effects of a decade of organic fertilizer substitution on vegetable yield and soil phosphorus pools, phosphatase activities, and the microbial community in a greenhouse vegetable production system 被引量:8
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作者 ZHANG Yin-jie GAO Wei +5 位作者 LUAN Hao-an TANG Ji-wei LI Ruo-nan LI Ming-yue ZHANG Huai-zhi HUANG Shao-wen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第7期2119-2133,共15页
Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated th... Partial substitution of chemical fertilizers by organic amendments is adopted widely for promoting the availability of soil phosphorus(P)in agricultural production.However,few studies have comprehensively evaluated the effects of longterm organic substitution on soil P availability and microbial activity in greenhouse vegetable fields.A 10-year(2009–2019)field experiment was carried out to investigate the impacts of organic fertilizer substitution on soil P pools,phosphatase activities and the microbial community,and identify factors that regulate these soil P transformation characteristics.Four treatments included 100%chemical N fertilizer(4 CN),50%substitution of chemical N by manure(2 CN+2 MN),straw(2 CN+2 SN),and combined manure with straw(2 CN+1 MN+1 SN).Compared with the 4 CN treatment,organic substitution treatments increased celery and tomato yields by 6.9-13.8%and 8.6-18.1%,respectively,with the highest yields being in the 2 CN+1 MN+1 SN treatment.After 10 years of fertilization,organic substitution treatments reduced total P and inorganic P accumulation,increased the concentrations of available P,organic P,and microbial biomass P,and promoted phosphatase activities(alkaline and acid phosphomonoesterase,phosphodiesterase,and phytase)and microbial growth in comparison with the 4 CN treatment.Further,organic substitution treatments significantly increased soil C/P,and the partial least squares path model(PLS-PM)revealed that the soil C/P ratio directly and significantly affected phosphatase activities and the microbial biomass and positively influenced soil P pools and vegetable yield.Partial least squares(PLS)regression demonstrated that arbuscular mycorrhizal fungi positively affected phosphatase activities.Our results suggest that organic fertilizer substitution can promote soil P transformation and availability.Combining manure with straw was more effective than applying these materials separately for developing sustainable P management practices. 展开更多
关键词 organic substitution management soil p pools phosphatase activity microbial community soil c/p pLS-pM
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叶酸通过JNK/p38 MAPK信号通路调节小鼠C2C12成肌细胞分化
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作者 孙缦利 邓海峰 +3 位作者 金少举 陈旭东 王兴红 范文娟 《中国病理生理杂志》 CAS CSCD 北大核心 2024年第2期317-325,共9页
目的:观察叶酸(folic acid,FA)对小鼠C2C12成肌细胞增殖和分化的影响并探讨其作用机制。方法:(1)在小鼠C2C12成肌细胞增殖阶段,采用不同浓度(0、2.5、5、10和20μmol/L)的FA处理C2C12细胞,显微镜下观察各组细胞的状态,MTT法检测细胞活力... 目的:观察叶酸(folic acid,FA)对小鼠C2C12成肌细胞增殖和分化的影响并探讨其作用机制。方法:(1)在小鼠C2C12成肌细胞增殖阶段,采用不同浓度(0、2.5、5、10和20μmol/L)的FA处理C2C12细胞,显微镜下观察各组细胞的状态,MTT法检测细胞活力,EdU法检测细胞增殖情况。(2)在小鼠C2C12成肌细胞分化阶段,将细胞分为对照(control,Ctrl)组(0μmol/L FA)和FA组(10μmol/L FA),于分化的第2天和第4天,采用免疫荧光染色和Western blot检测成肌细胞分化相关蛋白成肌细胞决定蛋白1(myoblast determination protein 1,MyoD)、成肌蛋白(myogenin,MyoG)和肌球蛋白重链(myosin heavy chain,MyHC)的表达水平,并统计各组细胞肌管形成情况。(3)在小鼠C2C12成肌细胞分化第4天时,加入FA处理0、1、3和6 h,采用Western blot检测各时点c-Jun氨基末端激酶(c-Jun N-terminal kinase,JNK)、磷酸化JNK(phosphorylated JNK,p-JNK)、p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)和磷酸化p38 MAPK(phosphorylated p38 MAPK,p-p38 MAPK)蛋白水平。(4)将分化4 d的小鼠C2C12成肌细胞分为Ctrl组、FA组、SP600125(JNK特异性抑制剂)组、SB2035805(p38 MAPK特异性抑制剂)组、FA+SP600125组和FA+SB203580组。C2C12成肌细胞先接受10μmol/L的SP600125或SB203580处理1 h,再经10μmol/L的FA处理24 h,FA组经10μmol/L FA处理24 h,Ctrl组不作处理。采用Western blot检测p-JNK、JNK、p-p38 MAPK、p38 MAPK和MyHC蛋白水平。结果:(1)与0μmol/L FA组相比,其余各浓度组的细胞数量明显增多,细胞活力显著提高(P<0.05),EdU阳性细胞率均显著增加(P<0.05)。(2)与Ctrl组相比,FA组MyoD、MyoG和MyHC的表达水平均显著提高(P<0.05),肌管融合指数显著增加(P<0.05或P<0.01)。(3)与0 h组相比,FA处理1、3和6 h后p-JNK/JNK和p-p38 MAPK/p38 MAPK的比值均显著升高(P<0.05或P<0.01),且随着处理时间的延长,p-JNK/JNK和p-p38 MAPK/p38 MAPK的比值呈现逐渐升高的趋势。(4)与Ctrl组相比,FA组p-JNK、p-p38 MAPK和MyHC蛋白水平显著升高(P<0.01);与FA组相比,FA+SP600125组p-JNK和MyHC蛋白水平显著降低(P<0.05),FA+SB203580组p-p38 MAPK和MyHC蛋白水平显著降低(P<0.05或P<0.01)。结论:FA可以通过激活JNK/p38 MAPK信号通路促进小鼠C2C12成肌细胞分化。 展开更多
关键词 叶酸 c2c12成肌细胞 骨骼肌 细胞分化 JNK/p38 MApK信号通路
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Thermodynamics of Fe-P-C in Mn-Based Solutions 被引量:2
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作者 Chen Erbao Yu Xuebin +1 位作者 Dong Yuanchi Guo Shangxing 《Journal of Iron and Steel Research International》 SCIE CAS CSCD 1997年第2期9-13,共5页
The solubilities of carbon in Mn based alloys containing P have been measured at 1 400 ℃ based on X C=0.271 9-0.094 0 X Fe -1.195 4 X P. By means of thermodynamic derivation and calculation, th... The solubilities of carbon in Mn based alloys containing P have been measured at 1 400 ℃ based on X C=0.271 9-0.094 0 X Fe -1.195 4 X P. By means of thermodynamic derivation and calculation, the relative activity coefficients and interactive parameters were derived. 展开更多
关键词 Mn based Fe p c system activity interaction coefficient theRMODYNAMIcS
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非线性M-C强度准则下预应力锚索加固边坡时效稳定性分析M-P法 被引量:1
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作者 邓东平 杨春会 谢志军 《岩土力学》 EI CAS CSCD 北大核心 2024年第4期1051-1066,共16页
拓展传统极限平衡方法在复杂条件下边坡稳定性分析中的适用性一直是岩土工程界的研究热点。众所周知,边坡岩土体剪切失效一般服从于非线性强度准则,而传统极限平衡方法仅适用于线性强度准则下边坡稳定性分析。此外,预应力锚索作为一种... 拓展传统极限平衡方法在复杂条件下边坡稳定性分析中的适用性一直是岩土工程界的研究热点。众所周知,边坡岩土体剪切失效一般服从于非线性强度准则,而传统极限平衡方法仅适用于线性强度准则下边坡稳定性分析。此外,预应力锚索作为一种主动防护措施,可极大地即时提高边坡稳定性而被广泛应用于中、大型边坡工程加固。然而,在应力松弛、蠕变效应以及腐蚀环境影响下预应力锚索加固边坡稳定性时效特征往往被忽视。由此,基于Morgenstern-Price(M-P)法,嵌入非线性Mohr-Coulomb(M-C)强度准则,并融入应力松弛与蠕变效应下锚索预应力损失模型以及腐蚀环境下锚索性能劣化模型,从而,建立非线性强度准则下预应力锚索加固边坡安全系数时程表达式。进一步,为了解决非线性强度准则下隐式嵌套公式难以求解的问题,归零化条间法向力初始值,并应用迭代循环求解策略,在引入循环终止允许误差判别条件后,可实现边坡稳定性理论真实结果的逼近求解。经过后续算例对比分析,验证了所提方法的可行性和合理性,与此同时,还研究了不同预应力损失速率和不同锈蚀环境下预应力锚索加固边坡稳定性的时效变化规律。 展开更多
关键词 边坡 极限平衡M-p 非线性M-c强度准则 预应力锚索加固 时效稳定性
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High frequency of the c.3207C>A (p.H1069Q) mutation in ATP7B gene of Lithuanian patients with hepatic presentation of Wilson's disease 被引量:5
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作者 Laimutis Kucinskas Jolanta Jeroch +6 位作者 Astra Vitkauskiene Raimundas Sakalauskas Vitalija Petrenkiene Vaidutis Kucinskas Rima Naginiene Hartmut Schmidt Limas Kupcinskas 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第38期5876-5879,共4页
AIM: To investigate the prevalence of the ATP7B gene mutation in patients with hepatic presentation of Wilson's disease (WD) in Lithuania. METHODS: Eleven unrelated Lithuanian families, including 13 WD patients w... AIM: To investigate the prevalence of the ATP7B gene mutation in patients with hepatic presentation of Wilson's disease (WD) in Lithuania. METHODS: Eleven unrelated Lithuanian families, including 13 WD patients were tested. Clinically WD diagnosis was established in accordance to the Leipzig scoring system. Genomic DNA was extracted from whole venous blood using a salt precipitation method. Firstly, the semi-nested polymerase chain reaction (PCR) technique was used to detect the c.3207C〉A (p.H1069Q) mutation. Patients not homozygous for the c.3207C〉A (p.H1069Q) mutation were further analyzed. The 21 exons of the WD gene were amplified in a thermal cycler (Biometra T3 Thermocycler, G0ttingen, Germany). Direct sequencing of the amplified PCR products was performed by cycle sequencing using fluorescent dye terminators in an automatic sequencer (Applied Biosystems, Darmstadt, Germany). RESULTS: Total of 13 WD patients (mean age 26.4 years; range 17-40; male/female 3/10) presented with hepatic disorders and 16 their first degree relatives (including 12 siblings) were studied. Some of WD patients, in addition to hepatic symptoms, have had extrahepatic disorders (hemolytic anemia 3; Fanconi syndrome 1; neurophsychiatric and behavioural disorder 2). Liver biopsy specimens were available in all of 13 WD patients (8 had cirrhosis; 1-chronic hepatitis; 3-acute liver failure, 1-1iver steatosis). Twelve of 13 (92.3%) WD patients had the c.3207C〉A (p.HI069Q) mutation, 6 of them in both chromosomes, 6 were presented as compound heterozygotes with additional c.3472-82delGGTTTAACCAT, c.3402delC, c.3121C〉T (p.RI041W) or unknown mutations. For one patient with liver cirrhosis and psychiatric disorder (Leipzig score 6), no mutations were found. Out of 16 first degree WD relatives, 11 (68.7%) were heterozygous for the c.3207C〉A (p.H1069Q) mutation. Two patients with fulminant WD died from acute liver failure and ii are in full remission under peniciilamine or zinc acetate treatment. Three women with WD successfully delivered healthy babies. CONCLUSION: The c.3207C〉A (p.HI069Q) missense mutation is the most characteristic mutation for Lithuanian patients with WD. Even 92.3% of WD patients with hepatic presentation of the disease are homozygous or compound heterozygotes for the p.H1069Q mutation. 展开更多
关键词 Wilson disease ATp7B gene c.3207c〉A(p.H1069Q) mutation cirrhosis Urine copper copper in liver biopsies
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Variation of Alkaline Phosphatase Activity in Sediments of Shrimp Culture Ponds and Its Relationship with the Contents of C,N and P 被引量:2
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作者 SUYuepeng MAShen DONGShuanglin 《Journal of Ocean University of China》 SCIE CAS 2005年第1期75-79,共5页
Nine enclosures (5 m x 5 m) were built in a Fenneropenaeus chinensis culture pond of Rushan Gulf in April, 2001. The probiotics and BIO ENERGIZER solution were applied for disparate treatments. Variations of alkaline ... Nine enclosures (5 m x 5 m) were built in a Fenneropenaeus chinensis culture pond of Rushan Gulf in April, 2001. The probiotics and BIO ENERGIZER solution were applied for disparate treatments. Variations of alkaline phosphatase ac- tivity (APA) and its relationship with the contents of C, N and P in sediments were studied. Results show that APA of sedi- ments increases from 3.096 nmolg-1min-1 to 5.407 nmol g-1min-1 in culture period; the bacteria biomass is not the only factor to determine APA; the contents of total P and total organic carbon have a significant positive correlation with APA, while that of total nitrogen has a negative correlation. In addition, the contents of inorganic P and organic P are not regular with APA. By comparison, TOC shows a more significant coherence with APA, meaning that organic pollution in sediments af- fects APA remarkably. 展开更多
关键词 ApA N c p SEDIMENTS fenneropenaeus chinensis
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Cloning and characterization of a novel gene (C17orf25) from the deletion region on chromosome 17p13.3 in hepatocelular carcinoma 被引量:8
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作者 QinWX WanDF 《Cell Research》 SCIE CAS CSCD 2001年第3期209-216,共8页
Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open rea(ling frame 25, previously named it HC71A), from the deletion r... Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open rea(ling frame 25, previously named it HC71A), from the deletion region on chromosome 17p13.3. The cDNA encodes a protein of 313 amino acids with a calculated molecular mass of 34.8 kDa. C17orf25 is divided into 10 exons and 9 introns, spanning 23 kb of genomic DNA. Northern blot analysis showed that the mRNA expression of C17orf25 was decreased in hepatocellular carcinoma samples as compared to adjacent noncancerous liver tissues from the same patients. The transfection of C17or25 into the hepatocellular carcinoma cell SMMC7721 and overexpression could inhibit the cell growth. The above results indicate that C17orf25 is a novel human gene, and the cloning and preliminary characterization of C17orf25 is a prerequisite for further functional analysis of this novel gene in human hepatocellular carcinoma. 展开更多
关键词 chromosome 17p13.3 1lss of heterozygosity hepatocellular carcinoma TRANSFEcTION novel human gene (c17orf25)
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Mitochondrial pathway of the lysine demethylase 5C inhibitor CPI-455 in the Eca-109 esophageal squamous cell carcinoma cell line 被引量:4
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作者 Xiao-Jie Xue Fei-Rong Li Jing Yu 《World Journal of Gastroenterology》 SCIE CAS 2021年第16期1805-1815,共11页
BACKGROUND Esophageal cancer is a malignant tumor of the digestive tract that is difficult to diagnose early.CPI-455 has been reported to inhibit various cancers,but its role in esophageal squamous cell carcinoma(ESCC... BACKGROUND Esophageal cancer is a malignant tumor of the digestive tract that is difficult to diagnose early.CPI-455 has been reported to inhibit various cancers,but its role in esophageal squamous cell carcinoma(ESCC)is unknown.AIM To investigate the effects and mechanism of the lysine demethylase 5C inhibitor,CPI-455,on ESCC cells.METHODS A methyl tetrazolium assay was used to detect the inhibitory effect of CPI-455 on the proliferation of Eca-109 cells.Apoptosis,reactive oxygen species(ROS),and mitochondrial membrane potential were assessed by flow cytometry.Laser confocal scanning and transmission electron microscopy were used to observe changes in Eca-109 cell morphology.The protein expression of P53,Bax,lysinespecific demethylase 5C(KDM5C),cleaved Caspase-9,and cleaved Caspase-3 were assayed by western blotting.RESULTS Compared with the control group,CPI-455 significantly inhibited Eca-109 cell proliferation.Gemcitabine inhibited Eca-109 cell proliferation in a concentrationand time-dependent manner.CPI-455 caused extensive alteration of the mitochondria,which appeared to have become atrophied.The cell membrane was weakly stained and the cytoplasmic structures were indistinct and disorganized,with serious cavitation when viewed by transmission electron microscopy.The flow cytometry and western blot results showed that,compared with the control group,the mitochondrial membrane potential was decreased and depolarized in Eca-109 cells treated with CPI-455.CPI-455 significantly upregulated the ROS content,P53,Bax,Caspase-9,and Caspase-3 protein expression in Eca-109 cells,whereas KDM5C expression was downregulated.CONCLUSION CPI-455 inhibited Eca-109 cell proliferation via mitochondrial apoptosis by regulating the expression of related genes. 展开更多
关键词 Lysine-specific demethylase 5c cpI-455 Esophageal squamous cell carcinoma caspase p53
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