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An efficient and green preparation of 5-aminophosphonate substituted pyrimidine nucleosides under solvent-free conditions

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Chinese Chemical Letters 2010年第10期21卷 1191-1194页

作者： xin ying zhang ying ying Qu Xue Sen Fan School of Chemistry and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

An environmentally benign and highly efficient one-pot preparation of α-aminophosphonates under solvent-free conditions was developed. By employing this method, 5-aminophosphonate substituted pyrimidine nucleosides were synthesized in good to excellent yields starting from 5-forrnyl-2＇-deoxyuridine, aniline and dimethylphosphite.

关键词： Aminophosphonate 5-Substituted pyrimidine nucleoside Solvent-free reaction Green synthesis

Transitions to Equilibrium State in Classical φ4 Lattice

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Communications in Theoretical Physics 2002年第8期38卷 157-162页

作者： WANG xin-Gang zhang ying HU Gang Department of Physics Beijing Normal University Beijing 100875 China The Abdus Salam International Centre for Theoretical Physics (ICTP) P.O. Box 586 34100 Trieste Italy Department of Physics Beijing Normal University Beijing 100875 China

Statistical behavior of a classical φ4 Hamiltonian lattice is investigated from microscopic dynamics. Thelargest Lyapunov exponent and entropies are considered for manifesting chaos and equipartition behaviors of the *** is found, for the first time, that for any large while finite system size there exist two critical couplings for the transitionsto equipartitions, and the scaling behaviors of these lower and upper critical couplings vs. the system size are numericallyobtained.

关键词： Hamiltonian system, measure synchronization, equilibrium, equipartition

Indoor channel characteristics based on wideband MIMO measurements at 5.25 GHz

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 46-50页

作者： GAO xin-ying zhang Jian-hua zhang Ping Key Laboratory of Universal Wireless Communications Ministry of Education Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

Extensive indoor channel measurements were conducted in Beijing with wideband multiple-input multiple-output （MIMO） sounder at 5.25 GHz. Both line-of-sight （LOS） and non-line-of-sight （NLOS） propagation were measured in the indoor office and hotspot scenarios. On the basis of measured data, statistical channel characteristics are presented in this article, including the empirical path loss （PL） models, three excess delay parameters, circular azimuth spread （CAS）, and circular elevation spread （CES）. Comparative analysis of different propagation mechanisms in two scenarios is conducted. These values are significant for indoor coverage and technical research of MIMO and orthogonal frequency division multiplexing （OFDM） for the international mobile telecommunications-advanced （IMT-Advanced） system.

关键词： channel measurement wideband MIMO path loss excess delay circular azimuth spread circular elevation spread IMT-Advanced

Euclidean distance harmonic method for establishing theoretical MAPK/Erk signaling pathway in treated breast cancer line MCF-7

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 80-84页

作者： zhang Hong-xin LU ying-hua zhang Jin-ling School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Hierarchical clustering algorithms, such as Pearson＇s correlation, Euclidean distance, Euclidean distance harmonic, Spearman rank correlation, Kendall＇s tau, and City-block distance, were used to find the best way to establish theoretical MAPK/Erk signaling pathway on the basis of breast cancer line MCF-7 gene expressions. The algorithm constructs a hierarchy from top to bottom on the basis of a self-organizing tree. It dynamically finds the number of clusters at each level. It was found that only Euclidean distance harmonic is fit for the analysis of the cascade composed from a RAF1 （c-Raf）, a MKNK1, a MAPKK （MEK1/2） to MAPK （Erk） in breast cancer line MCF-7. The result is consistent with the biological experimental MAP/Erk signaling pathway, and the theoretical MAPK/Erk signaling pathway on breast cancer line MCF-7 is set up.

关键词： hierarchical clustering signaling pathway,Euclidean distance harmonic

Synthesis of 1,2-allenic ketones through oxidation of homopropargyl alcohols with CrO_3(cat.)/TBHP under MWI

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Chinese Chemical Letters 2011年第3期22卷 268-271页

作者： xin ying zhang ying ying Qu Yang Yang Wang Xue Sen Fan School of Chemistry and Environmental Science Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

A CrO3 catalyzed oxidation of homopropargyl alcohols with tert-butyl hydroperoxide under microwave irradiation was found to be an efficient and rapid alternative for the preparation of 1,2-allenic *** advantages of th... 详细信息

关键词： Allenic ketones Oxidation Microwave irradiation Chromium(Ⅵ) oxide tert-Butyl hydroperoxide

Multidrug-resistant organisms in intensive care units and logistic analysis of risk factors

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World Journal of Clinical Cases 2022年第6期10卷 1795-1805页

作者： ying Han Jin zhang Hong-Ze zhang xin-ying zhang Ya-Mei Wang Infection Control Office Affiliated Hospital of Hebei UniversityBaoding 071000Hebei ProvinceChina

BACKGROUND Intensive care unit(ICU)patients are critically ill and have low *** will undergo various trauma medical procedures during diagnosis and *** use of high-dose hormones and broad-spectrum antibiotics will increase the incidence of nosocomial infection in ICU ***,it is necessary to explore the causes of nosocomial infection in ICU and provide basis for the prevention and control of nosocomial infection in *** To explore major pathogens of nosocomial infection in ICUs,methods of detection and drug resistance *** Risk factors of multidrug-resistant infection were analyzed to provide a basis for clinical rational use of antimicrobial drugs in the *** findings were used to standardize rational use of antimicrobial *** PhoenixTM100 automatic bacterial identification analyzer was used to for cell identification in specimens collected from the ICU between January 2016 and December *** sensitivity tests were carried out and drug resistance trends were analyzed using the optical disc diffusion *** ratios and corresponding 95%CI of independent variables were calculated using a logistic regression *** elimination(trend=0.1)was used as an inclusion criterion for multivariate *** data were analyzed using SPSS version 22.0,and P<0.05 was considered statistically *** We collected 2070 samples from ICU patients between January 2016 and December *** types comprised sputum(1139 strains,55.02%),blood(521 strains,25.17%),and drainage fluid(117 strains,5.65%).A total of 1051 strains of major pathogens,including Acinetobacter baumannii,Escherichia coli(***),Pseudomonas aeruginosa(***),Klebsiella pneumoniae(***)and Staphylococcus aureus,were detected,with a detection rate of 35.97%(378/1051).Most of these strains were resistant to *** rate of *** was 21.79%(229/1051),and it was generally sensitive to many antimicrobial dr

关键词： Multidrug-resistant organisms Intensive care Antibiotics Drug resistance

Preparation of nucleoside-pyridine hybrids and pyridine attached acylureas from an unexpected uracil ring-opening and pyridine ring-forming sequence

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Chinese Chemical Letters 2009年第10期20卷 1161-1165页

作者： Xue Sen Fan Xia Wang xin ying zhang Dong Feng ying ying Qu School of Chemistry and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

Novel pyrimidine nucleoside-3,5-dicyanopyridine hybrids （4） or pyridine attached acylureas （5） were selectively and efficiently prepared from the reaction of 2′-deoxyuddin-5-yl-methylene malononitrile （1）, malononitrile （2） and thiophenol （3） or from an unexpected uracil ring-opening and pyddine ring-forming sequence via the reaction of 1 and 3. It is the first time such a sequence has ever been reported.

关键词： Pyrimidine nucleoside Pyridine Acylureas Ring-opening and -forming reaction

Synthesis of fused pyran and arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane in ionic liquid

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Chinese Chemical Letters 2009年第4期20卷 387-390页

作者： Xue Sen Fan ying ying Qu xin ying zhang Xia Wang Jian Ji Wang School of Chemistry and Environmental Sciences Henan Key Laboratory for Environmental Pollution Control Henan Normal University Xinxiang 453007 China

Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis（4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl）methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis（pyranon-3-yl）methane hybrids with potential biological activities were constructed.

关键词： Ionic liquid Fused pyran Arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane Pyrimidine nucleoside Green synthesis

Correlation of continuous electroencephalogram with clinical assessment scores in acute stroke patients

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Neuroscience Bulletin 2012年第5期28卷 611-617页

作者： Xiyan xin ying Gao Hua zhang Kegang Cao Yongmei Shi Department of Neurology Dongzhimen Hospital Beijing University of Chinese Medicine Beijing 100700 China

Objective To compare electroencephalogram （EEG） symmetry values between stroke patients with different 28-day outcomes, and to assess correlations between clinical characteristics and 28-day outcomes. Methods Twenty-two patients presenting with acute ischemic stroke and persistent neurological deficits at EEG recording were incrementally included. At 28 days after admission, the modified Rankin scale （mRS） was used to evaluate the outcomes, based on which the patients were divided into two a posteriori groups, mRS = 6 and mRS 〈6. Student＇s t-test was used to compare these two groups in terms of brain symmetry index （BSI）, National Institutes of Health stroke scale （NIHSS）, Glasgow coma scale （GCS） and acute physiology and chronic health evaluation II （APACHE II） assessed at admission. Then EEG parameters, NIHSS, GCS and APACHE II were correlated with the mRS. Results There were significant differences in BSI, NIHSS, GCS, and APACHE II between the two groups. Survivors had lower BSI, NIHSS and APACHE II, and higher GCS values, compared with patients who died within 28 days after admission. Besides, BSI at admission had a positive correlation with mRS at 28 days （r = 0.441, P = 0.040）. NIHSS and APACHE II were also correlated with mRS （r = 0.736, P 〈0.000 1; r = 0.667, P = 0.001, respectively）. GCS at admission had a negative correlation with mRS （r = 0.656, P = 0.001）. Conclusion A higher BSI predicts a poorer short-term prognosis for stroke patients. Acute EEG monitoring may be of prognostic value for 28-day outcomes. The early prediction of functional outcomes after stroke may enhance clinical management and minimize short-term mortality.

关键词： electroencephalography brain symmetry index stroke prognosis