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Bibliometric analysis of the status and trend of biological soil crusts research from 1912 to 2023
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作者 XiaoJu Yang FaSi Wu +4 位作者 Long Li QingLin Guo ZongRen Yu SongCong Chen XueYong Zhao 《Research in Cold and Arid Regions》 CSCD 2024年第2期98-108,共11页
Biological soil crusts(BSCs)play an important role in soil development and ecological function,and it is more important for quantitatively analyzing the processes and trends of BSCs to identify the advantages and disa... Biological soil crusts(BSCs)play an important role in soil development and ecological function,and it is more important for quantitatively analyzing the processes and trends of BSCs to identify the advantages and disadvantages of BSCs research for the development and application of BSCs theory.Bibliometric analysis of 2,186 BSCs literatures from Web of Science showed an exponential growth trend,as China and the United States as the top 2 in terms of publication volume.High quality publications are mainly from European and American countries,such as the United States,Germany and Spain.The top 3 publishers are Journal of Arid Environments,Soil Biology&Biochemistry and Plant and Soil,and disciplines include ecology,environmental science,and soil science,etc..Research institutions mainly affiliate to the Chinese Academy of Sciences,United States Department of the Interior,United States Geological Survey,Hebrew University of Jerusalem,Consejo Superior de Investigaciones Cientificas,and Universidad Rey Juan Carlos.Authors mainly come from United States,Israel,Spain and China.Funds are mainly from the National Natural Science Foundation of China,Spanish Government,Chinese Academy of Sciences,and National Science Foundation of the United States.Biological soil crusts(biocrusts,cyanobacteria,lichens,moss crusts,bryophytes),drylands,climate change,photosynthesis and desert are high-frequency keywords.Future research will focus on the driving mechanisms of BSCs on global biogeochemical cycles,maintaining global biodiversity on important ecological processes,global C,N,and P cycles.The impact on biological invasion,sandstorms,and water balance,multifunctional and reciprocal mechanisms for maintaining the stability of desert and sandy ecosystems,and impact on the formulation of management policies for arid ecosystems,corresponding to global climate change,and the estimation of regional,local,and microscale distribution of BSCs based on machine deep learning modeling gradually focus on.The ecosystem service functions of BSCs,the soil and water conservation and soil stability mediated by BSCs in arid and semi-arid regions,and the excavation of stress resistant genes for BSCs will be emphasized. 展开更多
关键词 biological soil crusts Bibliometric analysis Web of science CITESPACE VOSviewer
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HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC ANALYSIS OF KR-008 IN BIOLOGICAL FLUIDS
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作者 Yun Seon SONG Jae Chun RYU Myungsoo KIM 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第12期1071-1074,共4页
A high-performance liquid chromatographic method for the simultaneous determination of KR-008 and its metabolite in biological fluids was developed The samples were injected directly without further treatment,the comp... A high-performance liquid chromatographic method for the simultaneous determination of KR-008 and its metabolite in biological fluids was developed The samples were injected directly without further treatment,the compounds were separated and analysed on a reversed- phase column under isocratic conditions,including ion pairing.Concentrations in urine and bile were determined by an external standard method.The detection limit was 0.8μg/ml in urine.Preliminary data showed that,following i.p.administration(120mg/kg)of KR-008 to rats,approximately 2.8% of the dose was excreted in urine as unchanged compound and more than 8.9% was as a metabolite;in bile it was 0.73% excreted as unchanged form and above 0.29% as the metabolite.The peak biliary concentration of KR-008 was 0.39mg/ml at 20min after dosing. 展开更多
关键词 KR HIGH-PERFORMANCE LIQUID CHROMATOGRAPHIC analysis OF KR-008 IN biological fluids
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Mechanisms of Sophora flavescens in the treatment of cervical squamous cell carcinoma based on comprehensive biological analysis,network pharmacology,and experimental verification
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作者 Ning-Jia Song Yuan Wang Ya-Ying Lin 《Cancer Advances》 2024年第10期1-8,共8页
Objective:This study used comprehensive bioinformatics analysis and network pharmacology analysis to investigate the potentially relevant mechanisms of Sophora flavescens against cervical squamous cell carcinoma.Metho... Objective:This study used comprehensive bioinformatics analysis and network pharmacology analysis to investigate the potentially relevant mechanisms of Sophora flavescens against cervical squamous cell carcinoma.Methods:Consistently altered genes involved in cervical squamous cell cancerization were analyzed in the GEO database.The chemical ingredients and target genes of Sophora flavescens were explored using the TCMSP database.We obtained the potential therapeutic targets of Sophora flavescens by intersecting the above genesets and validated them in the GEPIA database.The interaction between Sophora flavescens and target genes was predicted by molecular docking.RT-qPCR was used to verify the changes of target genes in HeLa cells treated with Sophora flavescens.Single-gene GSEA functional analysis were performed to determine the molecular mechanisms.Results:Fifteen genes related to the transformation of cervical squamous cell carcinoma were identified,among which AR and ESR1 were confirmed as targets for kaempferol,wighteone,formononetin,and phaseolinon.These compounds are the active ingredients in Sophora flavescens.Low expressions of AR and ESR1 correlate with a poor prognosis,while Sophora flavescens treatment increases the expression of AR and ESR1 in HeLa.GSEA analysis showed that AR and ESR1 mainly participate in the epithelial-mesenchymal transition in cervical squamous cell carcinoma.Conclusion:Sophora flavescens exert anti-tumor effects by targeting AR and ESR1,which may regulate cancer metastasis. 展开更多
关键词 cervical squamous cell carcinoma biological analysis network pharmacology Sophora flavescens
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Material Design and Experimental Analysis of a New Type of Semiconductor ER Fluids
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作者 朱石沙 魏宸官 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期155-159,共5页
To improve the electrorheological effect of electrorheological fluid (ERF), a new type of the electrosensitive particle material, polynaphthalene quinone was prepared, whose molecules contain blended atoms of nitrogen... To improve the electrorheological effect of electrorheological fluid (ERF), a new type of the electrosensitive particle material, polynaphthalene quinone was prepared, whose molecules contain blended atoms of nitrogen, oxygen, sulphur and big π bond conjugate system. In both DC and AC electric fields, the ERF material showed a distinct ER effect. Especially, in the alternating electric field, the shear stress of this material versus AC voltage has a better quadratic relation than that of the other materials. The experimental data showed that organic semiconductor polymers with big π bond conjugate system are a new type of electrosensitive particle materials which are worth well developing. 展开更多
关键词 electrorheological fluid(ERF) alternating electric field regression analysis
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Highly sensitive fluorescence quantification of irinotecan in biological fluids with the aid of second-order advantage 被引量:5
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作者 Hai Yan Fu Hai Long Wu Jin Fang Nie Yong Jie Yu Hong Yan Zou Ru Qin Yu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1482-1486,共5页
A rapid,green and highly sensitive excitation-emission matrix(EEM) fluorescence method was proposed for analysis of irinotecan(CPT-11) in biological fluids including human plasma and urine samples of uncalibrated ... A rapid,green and highly sensitive excitation-emission matrix(EEM) fluorescence method was proposed for analysis of irinotecan(CPT-11) in biological fluids including human plasma and urine samples of uncalibrated interferences with the aid of second-order advantage.Due to the serious spectral overlapping from biological matrices,the parallel factor analysis(PARAFAC) and the alternating normalization-weighted error(ANWE) have been recommended to perform directly calibration and overcome the problem which makes the traditional fluorospectrophotometer in trouble.Satisfactory results can be achieved.Furthermore, performance of the proposed method was evaluated based on figures of merit and some statistical parameters.The accuracy of both algorithms was validated by the elliptical joint confidence region(EJCR) test.The precision and repeatability were also investigated by the relative standard deviations(RSDs) of intra-day and inter-day. 展开更多
关键词 IRINOTECAN biological fluids Excitation-emission matrix fluorescence PARAFAC ANWE
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Development of a novel stability indicating RP-HPLC method for quantification of Connexin43 mimetic peptide and determination of its degradation kinetics in biological fluids 被引量:1
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作者 Rohit Bisht Ilva D. Rupenthal +1 位作者 Sreevalsan Sreebhavan Jagdish K. Jaiswal 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第6期365-373,共9页
Connexin43 mimetic peptide (Cx43MP) has been intensively investigated for its therapeutic effect in the management of inflammatory eye conditions, spinal cord injury, wound healing and iscbemia-induced brain damage.... Connexin43 mimetic peptide (Cx43MP) has been intensively investigated for its therapeutic effect in the management of inflammatory eye conditions, spinal cord injury, wound healing and iscbemia-induced brain damage. Here, we report on a validated stability-indicating reversed-phase high performance liquid chromatography (RP-HPLC) method for the quantification of Cx43MP under stress conditions. These included exposure to acid/base, light, oxidation and high temperature. In addition, the degradation kinetics of the peptide were evaluated in bovine vitreous and drug-free human plasma at 37℃. Detection of Cx43MP was carried out at 214 nm with a retention time of 7.5 min. The method showed excellent linearity over the concentration range of 0.9-250μg/mL (R2a0.998), and the limits of detection (LOD) and quantification (LOQ) were found to be 0.90 and 2.98 μg/mL, respectively. The accuracy of the method determined by the mean percentage recovery at 7.8, 62.5 and 250μg/mL was 96.79%, 98.25% and 99.06% with a RSD of〈 2.2%. Accelerated stability studies revealed that Cx43MP was more sensitive to basic conditions and completely degraded within 24 h at 37℃(0% recovery) and within 12 h at 80℃ (0.34% recovery). Cx43MP was found to be more stable in bovine vitreous (t1/2 slow= 171.8 min) compared to human plasma (t1/2slow = 39.3 min) at 37℃ according to the two phase degradation kinetic model. These findings are important for further pre-clinical development of Cx43MP. 展开更多
关键词 RP-HPLC DETERMINATION biological fluids
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Biological stability in drinking water: a regression analysis of influencing factors 被引量:1
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作者 LUWei ZHANGXiao-jian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第3期395-398,共4页
Some parameters, such as assimilable organic carbon(AOC), chloramine residual, water temperature, and water residence time, were measured in drinking water from distribution systems in a northern city of China. The me... Some parameters, such as assimilable organic carbon(AOC), chloramine residual, water temperature, and water residence time, were measured in drinking water from distribution systems in a northern city of China. The measurement results illustrate that when chloramine residual is more than 0.3 mg/L or AOC content is below 50 μg/L, the biological stability of drinking water can be controlled. Both chloramine residual and AOC have a good relationship with Heterotrophic Plate Counts(HPC)(log value), the correlation coefficient was -0.64 and 0.33, respectively. By regression analysis of the survey data, a statistical equation is presented and it is concluded that disinfectant residual exerts the strongest influence on bacterial growth and AOC is a suitable index to assess the biological stability in the drinking water. 展开更多
关键词 AOC biological stability HPC residual chloramines regression analysis
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Homotopy Analysis Method for Solving Biological Population Model 被引量:2
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作者 A.A.M.Arafa S.Z.Rida H.Mohamed 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期797-800,共4页
In this paper,the homotopy analysis method (HAM) is applied to solve generalized biological populationmodels.The fractional derivatives are described by Caputo's sense.The method introduces a significant improveme... In this paper,the homotopy analysis method (HAM) is applied to solve generalized biological populationmodels.The fractional derivatives are described by Caputo's sense.The method introduces a significant improvementin this field over existing techniques.Results obtained using the scheme presented here agree well with the analyticalsolutions and the numerical results presented in Ref.[6].However,the fundamental solutions of these equations stillexhibit useful scaling properties that make them attractive for applications. 展开更多
关键词 biological populations model fractional calculus homotopy analysis method Mittag-Leffier function
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Biological Fingerprinting Analysis of Interaction Between Taxoids in Taxus and Microtubule Protein by Microdialysis Coupled with High-performance Liquid Chromatography/Mass Spectrometry for Screening Antimicrotubule Agents 被引量:1
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作者 LEI Xiao-yuan KONG Liang +2 位作者 SU Xing-ye GUO Ming ZOU Han-fa 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第4期411-419,共9页
Some natural products, such as traditional Chinese medicines(TCMs), contain compounds with anticancer activity and have attracted a great interest in recent years as alternative anticancer therapies. A quick and con... Some natural products, such as traditional Chinese medicines(TCMs), contain compounds with anticancer activity and have attracted a great interest in recent years as alternative anticancer therapies. A quick and convenient assay for screening antimicrotubule compounds in which in vitro microdialysis/high-performance liquid chromatography (HPLC) is used to monitor the binding of the compounds extracted from TCM Taxus cuspidata Siebold & Zucc(Taxus) to microtubules is reported. It was observed that the extract of Taxus contains at least five compounds which have affinity interaction with microtubules by biological fingerprinting analysis, and they were identified as the taxoids of taxol, baccatin III, 10-deacetylbaccatin Ⅲ(10-DAB), cephalomannine and 7-epi-10-deacetyltaxol (7-epi-10-DAT) based on the comparison of their high-performance liquid chromatographic/mass spectrometric and UV spectra with those of the standard samples, both assembly-promoting and disassembly-inhibiting characteristics of those compounds were evaluated. It was observed that baccatin Ⅲ and 10-DAB bound to microtubules and the binding degrees were influenced by GTP. Competitive binding behavior of taxol with other four taxoids to microtubules was also investigated. 展开更多
关键词 Microdialysis/high-performance liquid chromatography(HPLC) biological fingerprinting analysis TAXOIDS MICROTUBULE TAXUS
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Establishment and Analysis of Regression Models between Sowing Time and Plant Productivity, Biological Yield of Forage Sorghum in Autumn Idle Land 被引量:1
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作者 ZHOU Han-zhang LIU Hong-xia +4 位作者 LIU Huan ZHOU Xin-jian WEI Zhi-min HOU Sheng-lin LI Shun-guo 《Agricultural Science & Technology》 CAS 2018年第1期51-58,共8页
[Objective]The aim was to establish the linear regression prediction models between sowing time and plant productivity, biological yield of forage sorghum in autumn idle land.[Method]The relationships between sowing t... [Objective]The aim was to establish the linear regression prediction models between sowing time and plant productivity, biological yield of forage sorghum in autumn idle land.[Method]The relationships between sowing time and plant productivity, biological yield of forage sorghum were simulated and compared by using field experiment and linear regression analysis.[Result] The sowing time had an important influence on the plant productivity and biological yield of forage sorghum in autumn idle land. The plant productivity and biological yield of forage sorghum both decreased with the delay of sowing time.The regression model between plant fresh weight and sowing time was ?fresh=0.618-0.015x; the regression model between plant dry weight and sowing time was ?dry=0.184-0.005x; and the regression model between biological yield and sowing time was yield=29 126.461-711.448x. During July 23rd to August 30th, when the sowing time was delayed by 1 day, the plant fresh weight of forage sorghum was reduced by 0.015 g, the plant dry weight was reduced by 0.005 g, and the yield was reduced by 711.448 kg/hm2. [Conclusion] The three regression models established in this study will provide theoretical support for the production of forage sorghum. 展开更多
关键词 Autumn idle land Forage sorghum Sowing time Plant productivity biological yield Regression model Regression analysis
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Infliximab is superior to other biological agents for treatment of active ulcerative colitis:A meta-analysis 被引量:6
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作者 Wei-Qun Mei Hui-Zhen Hu +2 位作者 Ying Liu Zhi-Chen Li Wei-Guo Wang 《World Journal of Gastroenterology》 SCIE CAS 2015年第19期6044-6051,共8页
AIM: To compare the efficacy and safety of biological agents for the treatment of active ulcerative colitis(UC).METHODS: PubMed, MEDLINE, EMBASE and the Cochrane library were searched to screen relevant articles from ... AIM: To compare the efficacy and safety of biological agents for the treatment of active ulcerative colitis(UC).METHODS: PubMed, MEDLINE, EMBASE and the Cochrane library were searched to screen relevant articles from January 1996 to August 2014. The mixedtreatment comparison meta-analysis within a Bayesian framework was performed using WinBUGS14 software.The proportions of patients reaching clinical response,clinical remission and mucosal healing in induction and maintenance phases were analyzed as efficacy indicators. Serious adverse events in maintenance phase were analyzed as safety indicators.RESULTS: The meta-analysis results showed that biological agents achieved better clinical response,clinical remission and mucosal healing than placebo.Indirect comparison indicated that in induction phase,infliximab was more effective than adalimumab in inducing clinical response(OR = 0.41, 95%CI:0.29-0.57), clinical remission(OR = 0.33, 95%CI:0.19-0.56) and mucosal healing(OR = 0.33, 95%CI:0.19-0.56), and golimumab in inducing clinical response(OR = 0.66, 95%CI: 0.39-2.33) and mucosal healing(OR = 2.15, 95%CI: 1.18-4.22). No significant difference was found between placebo and biological agents regarding their safety.CONCLUSION: All biological agents were superior to placebo for UC treatment in both induction and maintenance phases with a similar safety profile, and infliximab had a better clinical effect than the other biological agents. 展开更多
关键词 biological agents DRUG safety Efficacy META-analysis ULCERATIVE COLITIS
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Presence of hepcidin-25 in biological fluids: Bile,ascitic and pleural fluids
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作者 Jayantha Arnold Arvind Sangwaiya +3 位作者 Vijay Manglam Frank Geoghegan Mark Thursz Mark Busbridge 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第17期2129-2133,共5页
AIM: To examine body fluids such as ascitic fluid (AF),saliva,bile and pleural effusions for the presence of hepcidin using a novel radioimmunoassay (RIA).METHODS: Serum samples were collected from 25 healthy voluntee... AIM: To examine body fluids such as ascitic fluid (AF),saliva,bile and pleural effusions for the presence of hepcidin using a novel radioimmunoassay (RIA).METHODS: Serum samples were collected from 25 healthy volunteers (mean age: 36 ± 11.9 years,11 males,14 females).In addition bile was obtained from 12 patients undergoing endoscopic retrograde cholangiopancreatography (mean age: 66.9 ± 16.7 years,M:F = 5:7).Saliva was collected from 17 healthy volunteers (mean age: 35 ± 9.9 years,M:F = 8:9).Pleural and AF were collected from 11 and 16 patients [(mean age: 72 ± 20.5 years,M:F = 7:4) and (mean age: 67.32 ± 15.2 years,M:F = 12:4)],respectively.All biological fluid samples (serum,exudative and transudative fluids) were tested for the presence of hepcidin-25 molecule using RIA.RESULTS: Hepcidin-25 was detected in all biological fluids tested.The mean ± SD hepcidin-25 in serum was 15.68 ± 15.7 ng/mL,bile 7.37 ± 7.4 ng/mL,saliva 3.4 ± 2.8 ng/mL,exudative fluid 65.64 ± 96.82 ng/mL and transudative fluid 14.1 ± 17.8 ng/mL.CONCLUSION: We provide clear evidence that hepcidin-25 is present in bile,saliva,pleural and ascitic fluids.Hepcidin is likely to play a role here in innate immunity. 展开更多
关键词 HEPCIDIN Hepcidin assay Hepcidin in biological fluids Hepcidin in ascitic fluid BILE EXUDATES Antimicrobial peptides
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PROTON ACTIVATION ANALYSIS OF BIOLOGICAL MATERIALS
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作者 荣廷文 王玫珉 +4 位作者 万洪和 林森浩 鲍锦荣 孙建华 成源棣 《Nuclear Science and Techniques》 SCIE CAS CSCD 1992年第4期248-251,共4页
Biological materials of garlic, Wulong-tea and human hair were investigated by 14.2 MeV proton activation analysis using internal standard method. Elemental concentrations of Ca, Ti, V, Cr, Fe, Ni, Cu, Zn, Ge, Se, Sr,... Biological materials of garlic, Wulong-tea and human hair were investigated by 14.2 MeV proton activation analysis using internal standard method. Elemental concentrations of Ca, Ti, V, Cr, Fe, Ni, Cu, Zn, Ge, Se, Sr, Cd, La and Pb in biological samples were determined under the 5×10-8-2×10-5g/g of 展开更多
关键词 PROTON ACTIVATION analysis biological MATERIALS
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Analysis method and algorithm design of biological sequence problem based on generalized k-mer vector
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作者 LIU Wen-li WU Qing-biao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第1期114-127,共14页
K-mer can be used for the description of biological sequences and k-mer distribution is a tool for solving sequences analysis problems in bioinformatics.We can use k-mer vector as a representation method of the k-mer ... K-mer can be used for the description of biological sequences and k-mer distribution is a tool for solving sequences analysis problems in bioinformatics.We can use k-mer vector as a representation method of the k-mer distribution of the biological sequence.Problems,such as similarity calculations or sequence assembly,can be described in the k-mer vector space.It helps us to identify new features of an old sequence-based problem in bioinformatics and develop new algorithms using the concepts and methods from linear space theory.In this study,we defined the k-mer vector space for the generalized biological sequences.The meaning of corresponding vector operations is explained in the biological context.We presented the vector/matrix form of several widely seen sequence-based problems,including read quantification,sequence assembly,and pattern detection problem.Its advantages and disadvantages are discussed.Also,we implement a tool for the sequence assembly problem based on the concepts of k-mer vector methods.It shows the practicability and convenience of this algorithm design strategy. 展开更多
关键词 vector space biological sequence k-mer algorithm design analysis method.
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Developing Objective SensitivityAnalysis of Periodic Systems: Case Studies of Biological Oscillators 被引量:1
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作者 LU Bao-Yun YUE Hong 《自动化学报》 EI CSCD 北大核心 2012年第7期1065-1073,共9页
关键词 周期系统 生物系统 振荡器 敏感性分析 灵敏度指标 案例 开发 信号转导通路
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Synthesis, Molecular Spectroscopy, Computational, Thermal Analysis and Biological Activity of Some Orotic Acid Complexes
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作者 Mamdouh S. Masoud Alaa E. Ali +1 位作者 Ashimaa S. Abd Elfatah Gomaa E. Amer 《Open Journal of Inorganic Non》 CAS 2021年第1期1-22,共22页
Binary orotic acid metal complexes of Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), and two mixed metals complexes of (Co(II), Ni(II)) and (Ni(II), Cu(II)) were synthesized and characterized by elemental an... Binary orotic acid metal complexes of Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), and two mixed metals complexes of (Co(II), Ni(II)) and (Ni(II), Cu(II)) were synthesized and characterized by elemental analysis, IR, electronic spectra, magnetic susceptibility, and ESR spectra. The Analysis proved that the ligand has different coordination modes and the complexes were of octahedral, tetrahedral, and trigonal bipyramidal geometries. Molecular modeling techniques and quantum chemical methods have been performed for orotic acid to calculate charges, bond lengths, bond angles, dihedral angles, electronegativity (χ), chemical potential (μ), global hardness (η), softness (σ) and the electrophilicity index (ω). The thermal decomposition of the complexes was monitored by TGA, DTA, and DSC techniques under the N2 atmosphere. The thermal decomposition mechanisms of the complexes were suggested. The biological activity of orotic acid and some of the complexes are tested against antibacterial and antifungal organisms. 展开更多
关键词 Orotic Acid SYNTHESIS COMPLEXES CHARACTERIZATION Thermal analysis biological Activity
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Aptamer-Based DNA Materials for the Separation and Analysis of Biological Particles
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作者 Chenxu Zhu Chi Yao Dayong Yang 《Transactions of Tianjin University》 EI CAS 2021年第6期450-459,共10页
DNA is a biological macromolecule that carries genetic information in organisms.It provides a series of predominant bio-logical advantages,such as sequence programmability,high biocompatibility,and low biotoxicity.As ... DNA is a biological macromolecule that carries genetic information in organisms.It provides a series of predominant bio-logical advantages,such as sequence programmability,high biocompatibility,and low biotoxicity.As such,it is a unique polymer material that shows great potential for application in biological and medical fields.DNA aptamers are short DNA sequences with a specific ability of molecular recognition.With its discovery,the application prospect of DNA materials has broadened,especially for the separation and analysis of biological particles.In this review,the functions and characteristics of DNA aptamers are introduced,and the applications of DNA materials in cell/exosome separation and cancer detection are summarized.The application prospect and possible challenges of DNA materials are predicted. 展开更多
关键词 DNA materials DNA aptamer biological particle separation Disease analysis
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Paleoclimate Study of Mountain Ecosystems by Multiple Group Biological Analysis
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作者 Marina SKRYPNIKOVA Olga USPENSKAYA Olga KHOKHLOVA 《Journal of Mountain Science》 SCIE CSCD 2011年第1期24-36,共13页
Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysi... Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysis is exemplified by the paleoclimatic reconstruction for Carpathian and Altai Mountain ranges. For the "Skolevsky Beskidy" national park of Carpaty the paleoclimatic scenarios have been drown up aiming at the more precise definition of climatic conditions for the period of mass mountain slope terracing. The stability of terrace systems of various designs in the current climatic conditions has been assessed. It is shown that during periods of humid climate the terraces, whose designs have been focused on drainage, were built. In periods of dry and warm climate the terrace systems capable of accumulating water were built. Both these types of terrace systems are destroyed in nowadays. Only those terrace systems are stable which were adjusted by their builders to contrast variations of precipitation. For Western Altais the paleoclimatic scenario has been done to forecast the safety of the Bronze Age kurgans (burial earth mounds) with permafrost inside the construction. In the Altay region during the Holocene it has revealed two periods of sharp cooling, the peaks of which occurred in the intervals 4500- 4300 and 2500-2300 years pronounced climatic drying ago, and two periods of 4900-4700 and 130-70 years ago. Depletion of the algae composition in the layer corresponding to the last period of drying climate indicates a very sharp change in the parameters of moisture and turning the lake into a dry swamp. Periods of cold weather may have contributed to the formation of special ritual traditions of the Sakan tribes that require the frozen ground to bury the dead. The later climate fluctuations identified have not affected the safety of permafrost in burial mounds constructed in the V-III cc BC. 展开更多
关键词 Climatic reconstruction Complex group biological analysis of peat-sapropel sediments PALEOPEDOLOGY Soil evolution HOLOCENE
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Biological Analysis and Response to Low Phosphate Stress of Phosphate Transporter Family 1 (PHT1) Genes in Solanum tuberosum L.
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作者 Yangyang Du Yuanyuan Bao +2 位作者 Lu Zheng Qinglong Tian Xinyong Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第8期2325-2348,共24页
Inorganic phosphate(Pi)is one of the main nutrients necessary for plant growth.Phosphate transporters mediate the acquisition,transport and recycling of phosphate,which is essential for plant growth and development.Al... Inorganic phosphate(Pi)is one of the main nutrients necessary for plant growth.Phosphate transporters mediate the acquisition,transport and recycling of phosphate,which is essential for plant growth and development.Although PHT1 has been reported in many plants at home and abroad,it is rarely studied in potato.Therefore,it is of great significance to study the PHT1 family members in order to understand the molecular response mechanism of potato in low phosphate state.In this study,a total of 6 potato PHT1 genes were identified and isolated.It was found that after the expression of different members of potato PHT1 gene,there were certain differences in amino acids and proteins,and the transmembrane domains ranged from 6 to 12.The difference in the secondary and tertiary protein structure of potato PHT1 also led to a difference in protein morphology.In addition,the expression of the PHT1 gene in potato increased obviously during 3~9 h of Pi deficiency stress.Overall,the expression levels of different genes in roots,stems and leaves are distinctly different,but the expression levels of the StPHT1;6 and StPHT1;10 genes are very high in roots,stems and leaves,indicating that these two genes may participate in the absorption of Pi in potato and play a role in Pi translocation.These two genes play a major role in the regulation of expression under short-term Pi deficiency stress.Our results provide an important reference for further understanding the evolution and function of potato phosphate transporters,and have important significance for improving the ability of potato to tolerate low Pi. 展开更多
关键词 POTATO phosphate transporter gene short-term phosphate-deficiency stress biological analysis
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Electrochemical Determination of Dapoxetine HCI in Biological Fluids Using Coated Wire Electrode
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作者 Amani Salim Alturiqi 《Journal of Chemistry and Chemical Engineering》 2016年第6期277-282,共6页
Coated wire sensor for potentiometric determination ofDAP (dapoxetine HCI) in pure form and in biological fluidsbased on DAP-TPB (dapoxetine-tetraphenyl borate) as the sensing element in the presence of DOP (dioc... Coated wire sensor for potentiometric determination ofDAP (dapoxetine HCI) in pure form and in biological fluidsbased on DAP-TPB (dapoxetine-tetraphenyl borate) as the sensing element in the presence of DOP (dioctylphthalate) as the plasticizing solvent mediator was prepared. The best performance was obtained with a membrane composition of 10.0% (w/w) ion-pair, 45.0% DOP (w/w) and 45.0% PVC (w/w). The electrode showed a Nemstian response (with a slope of 58.70 mV decade-1) for the concentration range of 4.2 × 10-5-1.0 ×10-2 mol/L. It illustrates a relatively fast response time in the whole concentration range (-15 s) in a pH range of 3.0-7.5. The selectivity coefficients were determined in relation to several inorganic and organic species. DAP is determined successfully in pure solutions and in biological fuids using the standard additions and petentiometric titrations methods. 展开更多
关键词 DAP coated wire electrode biological fluids.
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