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Effect of matrix metalloproteinase-26(MMP-26) during embryo implantation in the mouse

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Chinese Science Bulletin 2002年第22期47卷 1884-1888,1938页

作者： ZHANG Jian LI Sumin TIAN Yongqiang ZHAO Yunge qing-xiang Amy Sang DUAN Enkui State Key Lab of Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100080China Department of Chemistry and Biochemistry and Institute of Molecular Biophysics Florida State UniversityTallahasseeFlorida 32306USA

Matrix metalloproteinase-26 (MMP-26, endo-metase and matrilysin-2), a novel member of the MMPs family, is detected not only in the placenta and uterus, but is widely expressed in malignant tumors from different sources as well as in diverse tumor cell lines. However, the function of MMP-26 in the reproductive system has never been reported. Expression of MMP-26 in mouse embryos and the function of the MMP-26 antibody during mouse embryo implantation was examined for the first time by injecting the uterine horn, immunohistochemistry, in situ hybridization, co-culture of mouse blastocysts and uterine monolayer epithelial cells, Western blot, RT-PCR, Northern blot and zymography. Our results show that there is strong expression of MMP-26 niRNA and protein in the mouse embryo. Furthermore, the MMP-26 antibody dramatically inhibited mouse embryo implantation and significantly inhibited adhesion and outgrowth of mouse blastocysts on in vitro uterine monolayer epithelial cells. At the same time, the MMP-26

关键词： matrix metalloproteinases (MMPs) MMP-26 embryo implantation mouse.

Sensitive determination of fenpropathrin,cyhalothrin and deltamethrin in environmental water samples using multiwalled carbon nanotubes cartridge prior to HPLC

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Chinese Chemical Letters 2008年第1期19卷 95-98页

作者： qing xiang Zhou Guo Hong Xie Jun Ping Xiao Wei Dong Wang Yu Jie Ding School of Chemistry and Environmental Sciences Henan Normal University Henan Key Laboratory for Environmental Pollution Control Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control Ministry of Education Xinxiang 453007 China College of Resources and Environment Henan Institute of Science and Technology Xinxiang 453003 China Department of Chemistry University of Science and Technology Beijing Beijing 100083 China

This paper described a new method for the trace determination of fenpropathrin, cyhalothrin and deltamethrin using multiwalled carbon nanotubes （MWCNTs） cartridge. Important parameters, such as the sample pH, eluent and its volume, sample flow rate and sample volume were investigated in detail. The linear ranges, the detection limits, and precisions （R.S.D.） were in the range of 0.1- 40 μg L^-11, 1.34.3 ng L^-1 and 2.3-2.8%, respectively. The performance of the proposed method was validated with real water samples, and the spiked recoveries were in the range of 91.7-117.8%, respectively. The experimental results demonstrated that the proposed method was an excellent alternative for the routine analysis of such pollutants in environmental samples. 2007 qing xiang Zhou. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Multiwalled carbon nanotubes Fenpropathrin Cyhalothrin Deltamethrin High performance liquid chromatography

Determination of aniline in environmental water samples by alternating-current oscillopolarographic titration

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Chinese Chemical Letters 2007年第6期18卷 730-733页

作者： Jun Ping Xiao qing xiang Zhou Xiao Ke Tian Hua Hua Bai Xian Fa Su Department of Chemistry University of Science and Technology Beijing Beijing 100083 China School of Chemistry and Environmental Sciences Henan Normal University Henan Key Laboratory for Environmental Pollution Control Xinxiang 453007 China

A new method for the determination of aniline in environmental water based on oscillopolarographic titration was presented in this paper. Several factors including the kind, concentration, and volume of acid, the dosage of potassium bromide, the temperature and concentration of concomitant substances were investigated in detail. The experimental results indicated that this method was simple, rapid, and sensitive. The linear range was 8.367 × 10(?4) to 2.789 × 10(?2) mol L(?1), the relative standard deviation (R.S.D.) was lower than 0.96%, and the spiked recoveries of aniline in environmental water samples were in the range of 99.4–106.9% under the optimal conditions. The results indicated that the present method could be used as an alternative method for aniline determination in realworld water samples.

关键词： Alternating-current oscillopolarographic titration Aniline Potassium bromide

Solid Solute Regularity of La Atom inα-Fe Supercell by First-principles

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Journal of Iron and Steel Research International 2016年第11期23卷 1213-1218页

作者： Cai-xia WANG Jian YANG Sha LIU Xiao-lei XING Ji-bo WANG Xue-jun REN qing-xiang YANG State Key Laboratory of Metastable Materials Science and Technology Yanshan University School of Materials Science and Engineering University of Science and Technology Beijing School of Engineering Liverpool John Moores University

The structure stability, elastic property and electronic structure of a-Fe supercell with La atom were inves- tigated by first-principles, in which, generalized gradient approximation （GGA） with the Perdew Burke Ernzerhof （PBE） was used as exchange-correlation functional, a-Fe supercells with La atom include a-Fe supercell with La atom in octahedral interstitial solid solute （La-OISS）, that with La atom in tetrahedral interstitial solid solute （La-TISS） and that with La atom in substitutional solid solute （La-SSS）. The results show that the La-SSS a-Fe supercell is more stable than La-OISS one. The resistance to volume change, reversible deformation and stiffness of La-OISS a-Fe supercell are stronger than those of La-SSS one. Moreover, the degrees of anisotropy and ionization in La-SSS a-Fe supercell are both stronger than those in La-OISS one. The bonding strength between La atom and Fe atom in La-SSS a-Fe supercell is larger than that in La-OISS one.

关键词： La atom a-Fe supercell solid solution first-principles bonding strength

Overview of global monthly surface temperature data in the past century and preliminary integration

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Advances in Climate Change Research 2014年第3期5卷 111-117页

作者： XU Wen-Hui LI qing-xiang YANG Su XU Yan National Meteorological Information Center China Meteorological Administration

This paper analyzes the status of existing resources through extensive research and international cooperation on the basis of four typical global monthly surface temperature datasets including the climate research dataset of the University of East Anglia(CRUTEM3), the dataset of the U.S. National Climatic Data Center(GHCN-V3), the dataset of the U.S. National Aeronautics and Space Administration(GISSTMP), and the Berkeley Earth surface temperature dataset(Berkeley). China's first global monthly temperature dataset over land was developed by integrating the four aforementioned global temperature datasets and several regional datasets from major countries or regions. This dataset contains information from 9,519 stations worldwide of at least 20 years for monthly mean temperature, 7,073 for maximum temperature, and 6,587 for minimum temperature. Compared with CRUTEM3 and GHCN-V3, the station density is much higher particularly for South America, Africa,and Asia. Moreover, data from significantly more stations were available after the year 1990 which dramatically reduced the uncertainty of the estimated global temperature trend during 1990e2011. The integrated dataset can serve as a reliable data source for global climate change research.

关键词： Global monthly surface temperature dataset Integration of multi-source data Climate change

Performance of digital data acquisition system in gamma-ray spectroscopy

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Nuclear Science and Techniques 2021年第8期32卷 12-22页

作者： Di-Wen Luo Hong-Yi Wu Zhi-Huan Li Chuan Xu Hui Hua xiang-qing Li xiang Wang Shuang-Quan Zhang Zhi-Qiang Chen Chen-Guang Wu Yu Jin Jie Lin State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China

A newly developed digital data acquisition system,which is based on the digital pulse processor Pixie-16 modules by XIA LLC,was tested with the c-ray detector array of the China Institute of Atomic Energy using the cray source and in-beam c-rays.A comparison between this digital data acquisition system and the conventional analog data acquisition system was *** a low count rate,both systems exhibit good and comparable energy *** a high count rate above 8.8 k/s,while the energy resolution obtained by the analog system deteriorates significantly,the energy resolution obtained by the digital system is nearly ***,experimental data with higher statistics can be collected by the digital *** advantage of this digital system over the conventional analog system can be ascribed to its excellent capability of handling pile-up pulses at higher count rates,and the fact that it has nearly no dead time in data transmission and conversion.

关键词： Digital data acquisition system Gamma spectroscopy Energy resolution

Effect of steam-flaking on chemical compositions,starch gelatinization,in vitro fermentability,and energetic values of maize,wheat and rice

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Journal of Integrative Agriculture 2015年第5期14卷 949-955页

作者： QIAO Fu-qiang WANG Fei REN Li-ping ZHOU Zhen-ming MENG qing-xiang BAO Yu-hong State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural University College of Animal Sciences Beijing University of Agriculture Tibetan Academy of Agricultural and Forestry Sciences

Intact and steam-flaked grains of maize,wheat and rice（with whole hulls） were analyzed for chemical composition,starch gelatinization degree（SGD） and in vitro fermentation characteristics to investigate the influence of cereal type and steam-flaking（SF） processing on their nutritive *** treatments were arranged in a 3×2 factorial *** differences（P〈0.001） in chemical composition and energetic values were observed among the different cereal *** and gas production（GP） rate was significantly increased（P〈0.001） by SF *** processing also increased（P〈0.01） the proportion of propionic acid and decreased the acetic：propionic acid ratio in ***-flaking also increased organic matter digestibility and the energetic value of the cereal grains,especially *** on these results,rice probably is more amendable to SF processing than maize and *** conclusion,it is feasible to partially substitute maize grain with wheat or rice in ruminant diets,and steam-flaking can significantly improve the nutritional value of wheat and rice grains.

关键词： maize wheat starch steam cereal grains propionic Wheat proportion partially

Increased index of microcirculatory resistance in older patients with heart failure with preserved ejection fraction

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Journal of Geriatric Cardiology 2018年第11期15卷 687-694页

作者： Zhuo XU Hui-Ping GU Yang GU Wei SUN Kun YU Xi-Wen ZHANG xiang-qing KONG Department of Cardiology the First Affiliated Hospital of Nanjing Medical University Nanjing China Department of Cardiology the Affiliated Huai'an No.1 People's Hospital of Nanjing Medical UniversityHuai'an China

Objective To study the coronary microvascular function in older patients with heart failure with preserved ejection fraction (HFpEF) using an invasive pressure–temperature sensor guidewire. Methods Patients undergoing echocardiography and cardiac catheterization examinations for exertional dyspnea and a positive stress test were retrospectively enrolled from January 2014 to November 2017, and were allocated into the control group or HFpEF group. The HFpEF group was secondary divided into two groups according to the age of 65 years. Comparing the clinical features and values obtained in examinations between the three groups, multivariate regression analysis was used to analyze the predictors of left ventricle end diastolic pressure (LVEDP). Results There were 87 patients enrolled in this study. The older HFpEF patients (n = 32) were more likely to be female;and had the most comorbidities, such as diabetes mellitus, atrial fibrillation, and chronic kidney dysfunction (CKD) with a low estimated glomerular filtration rate (eGFR), and had a similar hypertensive prevalence as the adult HFpEF group (n = 24), whose mean LVEDP and index of microcirculatory resistance (IMR) were highest in comparison to the adult HFpEF patients and controls (n = 31). The coronary flow reserve (CFR) in the older HFpEF and adult HFpEF groups was similarly reduced. In the regression analysis, the IMR linearly correlated to LVEDP, and was the only independent predictor of LVEDP. Conclusions An increased IMR and reduced CFR were characteristics of microvascular dysfunction in older HFpEF patients. The IMR independently had a positive linear correlation with LVEDP. Microvascular rarefaction might be a subsequent pathological progression in the development of HFpEF.

关键词： Heart failure Ejection fractions Microcirculatory resistance Microvascular dysfunction

Synthesis, complexation properties and crystal structure of 4',5'-dibromo-oxylyl-17-crown-5 ether

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Chinese Journal of Chemistry 1996年第5期14卷 447-453页

作者： XIONG,Guo-xiang ZHOU,qing-Fu XU,Hui-JunInstitute of Photographic Chemistry,Chinese Academy of Sciences,Beijing 100101,China Institute of Photographic Chemistry Chinese Academy of Sciences Beijing 100101 China

4',5'-Dibromo-o-xylyl-17-crown-5 ether (2BrB17C5) was synthesized,starting from 1,2-dibromo-4,5-bis(bromomethyl)-benzene and tetraethylene glycol,and was characterized by 1H NMR,MS and elemental *** yellow prismatic single crystal obtained from anhydrous ethanol was investigated by X-ray structural *** complexation properties toward alkali metal ions were examined using the solvent extraction method and UV absorption *** crown ether was found to be conformationally deformed and oblate-like and is highly selective for lithium ion.

关键词： Crown ether complexation crystal structure