检索结果-南通市图书馆

Study on the inclusion interactions of berberine hydrochloride and cucurbit[7] by spectrofluorimetry

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第3期20卷 322-325页

作者： Yan Ping li Hao Wu li ming du Analytical and Testing Center Shanxi Normal University Linfen 041004 PR China

The inclusion interaction between berberine hydrochloride （BRH） and cucurbit[7] （CB[7]） has been studied by spectrofluorimetry. The result showed that CB[7] interaction with BRH to form a stable inclusion complex with an association constant of 9.57 × 10^4 L/mol and the fluorescence intensity of the complex was enhanced in 17 times higher than that of the studied drug itself. Based on the significant enhancement of fluorescence intensity of BRH in inclusion complex, a spetrofluorimetric method with high sensitivity and selectivity was developed for the determination of BRH in aqueous solution. The linear range of the method was 3.2- 2 × 10^3 ng/mL with a detection limit of 1.1 ng/mL. The proposed procedure could be applied successfully to determination of BRH remained in pharmaceutical dosage forms, spiked human plasma and urine with satisfactory results.

关键词： Berberinc hydrochloride Cucurbit Spectrofluorimetry Inclusion interaction

Determination of L-phenylalanine by cucurbit[7]uril sensitized fluorescence quenching method

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第7期22卷 851-854页

作者： Chang Feng li li ming du Hao Wu Ying Xia Chang Analytical and Testing Center Shanxi Normal University Linfen 041004 China School of Chemistry and Materials Science Shanxi Normal University Linfen 041004 China

The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation （R.S.D） was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe.

关键词： L-phenylalanine Palmatine hydrochloride Cucurbituril Fluorescent probe

Study on the inclusion interaction of methylated-β-cyclodextrins with albendazole by spectrofluorimetry and its application

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第8期19卷 951-954页

作者： Guo Yan Zhao Hao Wu Sheng li Dong li ming du Analytical and Testing Center Shanxi Normal University Linfen 041004 China

The inclusion interaction between three types of methylated-β-cyclodextrins （Me-β-CDs） and albendazole （ABZ） was studied by spectrofluorimetry. The result showed that Me-β-CDs reacted with ABZ to form an inclusion complex, 1： 1 stoichiometry for Me- β-CDs-ABZ complex was established and its association constant have been determined from fluorescence data by Benesi- Hildebrand＇s method （double reciprocal plots）. It was noted that 2,6-DM-β-CD exhibited stronger binding ability than other Me-β- CDs. Based on the significant enhancement of fluorescence intensity of inclusion complex, a simple and highly sensitive fluorimetric method is proposed for the determination of ABZ in the presence of 2,6-DM-β-CD. The proposed method was successfully applied to the determination of ABZ in tablets and human urine.

关键词： Methylated-β-cyclodextrins Albendazole Spectrofluorimetry

Sliding tribological characteristics of Ti48Zr20Nb12Cu5Be15 metallic glass matrix composites under different conditions

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2018年第3期25卷 282-290页

作者： Zhong-kun Bai li-ming du ming Chen Min Zhang Xiao-hui Shi Hui-jun Yang College of Materials Science and Engineering TaiyuanUniversity of Technology Taiyuan 030024 Shanxi China

A systematic research on the tribological characteristics of Ti48Zr20Nb12Cu5Be15 metallic glass matrix composites was performed under different normal loads in dry condition and simulated seawater. The wear rate decreased with the increase in normal load under dry and simulated seawater conditions. The friction coefficient was lower in the dry condition than in the simulated seawater. The composite showed better wear resistance at lower loads （3, 5 and 10 N） hut poor wear resistance at higher loads （15 and 17 N） in the simulated seawater. The analysis of the worn surface illustrated that the wear mechanism in dry condition was plastic deformation, adhesive wear and abrasive wear at 3 and 5 N, while it was abrasive wear and adhesive wear at 10, 15 and 17 N. The wear mechanism in simulated seawater was abrasive wear, plastic deformation and adhesive wear at 3 N, adhesive wear at 10 N, and abrasive wear at 5, 15 and 17 N. At the same time, the corrosion occurred during wear tests in the simulated seawater.

关键词： Amorphous material Rapid solidification Friction Wear Corrosion

Determination of Sparfloxacin in Human Urine by Reversed-Phase High Performance liquid Chromatography With Nitrous Acid and Hydroiodic Pre-Column Derivatization

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2001年第11期12卷 1007-1010页

作者： li ming du Zhe Feng FAN Jin li QIAO Jing Ping WANG Analysis and Test Center Shanxi Teachers UniversityLingfen 041004 Department of Chemistry Arts and Sciences CollegeTaiyuan University of TechnologyTaiyuan 030006

Sparfloxacin can be oxidized by nitrous acid, then react with hydroiodic acid to form a fluorescent derivative. Based on this, a reversed-phase high performance liquid chromatographic pre-column derivatization new method is described for the determination of sparfloxacin in human urine. The linear range is 0.05 mg/L to 4.0 mg/L, the recoveries are 91.5%similar to 95.7% and the RSD is 1.2%similar to4.2%. The results showed that this method is suitable for the determination of sparfloxacin in human urine.

关键词： sparfloxacin HPLC pre-column derivatization human urine

Hepatocellular carcinoma:An analysis of the expression status of stress granules and their prognostic value

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第6期16卷 2571-2591页

作者： Qing-Shuai Ren Qiu Sun Shu-Qin Cheng li-ming du Ping-Xuan Guo Department of Cardiovascular Surgery North China University of Science and Technology Affiliated HospitalTangshan 063000Hebei ProvinceChina Department of Hepatobiliary Kailuan General HospitalTangshan 063000Hebei ProvinceChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalTianjin Institute of Digestive DiseasesTianjin Key Laboratory of Digestive DiseasesTianjin 300000China Department of Traditional Chinese Medicine Kailuan General HospitalTangshan 063000Hebei ProvinceChina Department of Anesthesiology Kailuan General HospitalNorth China University of Science and TechnologyTangshan 063000Hebei ProvinceChina

BACKGROUND Hepatocellular carcinoma(HCC)is a global popular malignant tumor,which is difficult to cure,and the current treatment is *** To analyze the impacts of stress granule(SG)genes on overall survival(OS),survival time,and prognosis in *** The combined The Cancer Genome Atlas-liver Hepatocellular Carcinoma(TCGA-liHC),GSE25097,and GSE36376 datasets were utilized to obtain genetic and clinical *** hub gene numbers and corresponding coefficients were determined using the Least absolute shrinkage and selection operator model approach,and genes for constructing risk scores and corresponding correlation coefficients were calculated according to multivariate Cox regression,*** prognostic model’s receiver operating characteristic(ROC)curve was produced and plotted utilizing the time ROC software *** models were constructed to predict the outcomes at 1,3,and 5-year OS prognostications with good prediction *** We identified seven SG genes(DDX1,DKC1,BICC1,HNRNPUL1,CNOT6,DYRK3,CCDC124)having a prognostic significance and developed a risk score *** findings of Kaplan-Meier analysis indicated that the group with a high risk exhibited significantly reduced OS in comparison with those of the low-risk group(Pduals with HCC in the TCGA-HCC *** Ontology and Gene Set Enrichment Analysis suggested that these SGs might be involved in the cell cycle,RNA editing,and other biological *** Based on the impact of SG genes on HCC prognosis,in the future,it will be used as a biomarker as well as a unique therapeutic target for the identification and treatment of HCC.

关键词： Stress granule genes Hepatocellular carcinoma Gastrointestinal neoplasms Bioinformatics prognosis Prognostic value

Analysis of Genetic Diversity of Processing Apple Varieties

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2006年第10期5卷 745-750页

作者： SONG Ye ZHAI Heng YAO Yu-xin li ming du Yuan-peng College of Horticultural Science and Engineering Shandong Agricultural University Taian 271018 P.R.China

Genetic diversity of 18 processing apple varieties and two fresh varieties were evaluated using 12 simple sequence repeats （SSR） primer pairs previously identified in Malus domestica Borkh. A total of 87 alleles in 10 loci were detected using 10 polymorphic SSR markers selected within the range of 5-14 alleles per locus. All the 20 varieties could be distinguished using two primer pairs and they were divided into four groups using cluster analysis. The genetic similarity （GS） of groups analyzed using cluster analysis varied from 0.14 to 0.83. High acid variety Avrolles separated from other varieties with GS less than 0.42. The second group contained Longfeng and Dolgo from Northeast of China, the inherited genes of Chinese crab apple. The five cider varieties with high tannin contents, namely, Dabinette, Frequin rouge, Kermerrien, ***, and *** were clustered into the third group. The fourth group was mainly composed of 12 juice and fresh varieties. Principal coordinate analysis （PCO） also divided all the varieties into four groups. Juice and fresh apple varieties, Longfeng and Dolgo were clustered together, respectively, using both the analyses. Both the analyses showed there was much difference between cider and juice varieties, cider and fresh varieties, as well as Chinese crab apple and western European crab apple, whereas juice varieties and fresh varieties had a similar genetic background. The genetic diversity and differentiation could be sufficiently reflected by combining the two analytical methods.

关键词： processing apple varieties genetic diversity simple sequence repeats cluster analysis principal coordinate analysis

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang liu Xiang li Shen du ming Gao Yanbin Yin Jiongming Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

during the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

Human umbilical cord-derived endothelial progenitor cells promote growth cytokines-mediated neorevascularization in rat myocardial infarction

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2009年第5期122卷 548-555页

作者： HU Cheng-heng li Zhi-ming du Zhi-min ZHANG Ai-xia YANG Da-ya WU Gui-fu Division of Cardiology First Affiliated Hospital and Key Laboratory on Assisted Circulation Ministry of Health of China Sun Yat-sen University Guangzhou Guangdong 510080 China

Background Cell-based vascular therapies of endothelial progenitor cells （EPCs） mediated neovascularization is still a novel but promising approach for the treatment of ischemic disease. The present study was designed to investigate the therapeutic potentials of human umbilical cord blood-derived EPCs （hUCB-EPCs） in rat with acute myocardial infarction. Methods Human umbilical cord blood （hUCB） mononuclear cells were isolated using density gradient centrifugation from the fresh human umbilical cord in healthy delivery woman, and cultured in M199 medium for 7 days. The EPCs were identified by double-positive staining with 1,1＇-dioctadecyl-3,3,3＇,3＇-tetramethylindocarbocyanine percholorate-labeled acetylated low-density lipoprotein （DiI-Ac-LDL） and fluorescein isothiocyanate-conjugated Ulex europaeus lectin （FITC-UEA-I）. The rat acute myocardial infarction model was established by the ligation of the left anterior descending artery. The hUCB-EPCs were intramyocardially injected into the peri-infarct area. Four weeks later, left ventricular function was assessed by a pressure-volume catheter. The average capillary density （CAD） was evaluated by anti-VIII immunohistochemistry staining to reflect the development of neovascularization at the peri-infarct area. The graft cells were identified by double immunofluorescence staining with human nuclear antigen （HNA） and CD31 antibody, representing human origin of EPCs and vascular endothelium, respectively. Expressions of cytokines, proliferating cell nuclear angigen （PCNA）, platelet endothelial cell adhesion molecule （PECAM） and vascular endothelial growth factor （VEGF） were detected to investigate the underlying mechanisms of cell differentiation and revascularization. Results The donor EPCs were detectable and integrated into the host myocardium as confirmed by double-positive immunofluorescence staining with HNA and CD31. And the anti-VIII staining demonstrated a higher degree of microvessel formation in EPCs transplanted

关键词： human umbilical cord blood endothelial progenitor cells acute myocardial infarction neovascularization