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Optimization of multicomponent solvent selection in high-performance liquid chromatography using a statistical method

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Chinese Journal of Chemistry 1991年第3期9卷 222-230页

作者： WANG,Qin-Sun GAO,Ru-yu WANG,Heng-yan yan,Bing-Wen National Laboratory of Elemento-Organic Chemistry,Nankai University,Tianjin 300071 National Laboratory of Elemento‐Organic Chemistry Nankai University Tianjin 300071

A computer-assisted method is presented for optimization of multicomponent solvent mobile phase selection for separation of O-ethyl-N-isopropyl phosphoro(thioureido)thioates in reversed-phase HPLC and four geometric isomers of pesticides Decis in normal-phase *** method is based on Snyder's solvent selection triangle concept using a statistical *** optimization of the separation over the experimental region is based on a special polynomial esti- mation from seven experimental runs,and resolution(R_s)is used as the selection *** agreement was obtained between predicted data and experimental results.

关键词： Optimization of multicomponent solvent selection in high-performance liquid chromatography using a statistical method high

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A Green Partnership

Beijing Review 2009年第29期52卷 12-13页

作者： yu yan & yan WEI

China and the United States join hands to work for a better environment clean energy has become a ’promising area for China-U.S. i partnership that will contribute to the long-term stability and growth of the two cou... 详细信息

关键词： A Green Partnership

Campylobacter enteritis in adult patients with acute diarrhea from 2005 to 2009 in Beijing, China

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Chinese Medical Journal 2011年第10期124卷 1508-1512页

作者： CHEN Jie SUN Xin-ting ZENG Zheng yu yan-yan Department of Infectious Diseases Peking University First Hospital Beijing 100034 China

Background There has been a marked global increase in the incidence of human Campylobacter enteritis in recent years. This study investigated the epidemiological and clinical features of Campylobacter enteritis in adult patients suffering from acute *** This was a retrospective review of Campylobacter enteritis in adult patients with acute diarrhea presenting at Beijing University First Hospital, Beijing, China, in the summer and autumn （April to October） of 2005 to 2009. The data collected included the species of campylobacter identified, and the age, gender, clinical manifestations and results of laboratory test on stool samples collected from the patients. Campylobacter sensitivity tests to various antimicrobial agents were conducted on 80 specimens. Chi-square tests were applied using SPSS13.0 software and a two-sided P value of 〈0.05 was considered statistically *** Campylobacter spp. isolated from the stool specimens of 142 patients with diarrhea represented 14.9% of all the cases examined. C. jejuni was identified in 127 patients （89.4%） and C. coli in 15 others （10.6%）. The infection incidence was highest in the age range of 21-30 years which comprised 21.7% of the total cases examined. Most cases of diarrhea （46 patients） occurred in June. Watery diarrhea （97.2%）, abdominal pain （72.5%） and fever （64.8%） were the most common manifestations of enteric campylobacteriosis. Only four patients （2.8%） had bloody diarrhea. The antimicrobial resistance rates were： cefoperazone （100%）, levofloxacin （61.3%）, gentamicin （12.5%）, erythromycin （6.3%）, and azithromycin （2.5%）.Conclusions Campylobacter was prevalent among adults with acute diarrhea from 2005 to 2009 in Beijing, China. The large number of those afflicted by the disease warrants the commission of a large multicenter study to determine the extent of enteric campylobacteriosis in this region

关键词： Campylobacter enteritis drug resistance signs and symptoms

Management of chronic liver diseases and cirrhosis: current status and future directions

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Chinese Medical Journal 2020年第22期133卷 2647-2649页

作者： Jing-Hang Xu yan-yan yu Xiao-yuan Xu Department of Infectious Diseases Peking University First HospitalBeijing 100034China

Chronic liver diseases(CLD)and cirrhosis are substantial health burdens *** 2017,with an estimation of 1.5 billion cases,the age-standardized prevalence increases by 10.4%when compared with that in 2007.[1]Globally,the most common etiologies of CLD and cirrhosis are non-alcoholic fatty liver disease(NAFLD),followed by hepatitis B virus(HBV),hepatitis C virus(HCV),and alcohol liver disease(ALD)in 2017.[1]Similarly,NAFLD is a common cause of CLD and cirrhosis in China,with an estimation of 173 to 310 million cases according to recent surveys.

关键词： cirrhosis diseases NAFLD

Application of H infinite control to ship steering system

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Journal of Marine Science and Application 2006年第1期5卷 6-11页

作者： LIU Sheng yu Ping LI yan-yan DU yan-chun School of Automation Harbin Engineering University Harbin 150001 China

Because the general object of ship steering control system is singular, the state Of rudder force and the state of disturbance are separated, and the generalized yaw output disturhance is obtained. Furthermore, singular system control problem of ship yaw and sway coupled system is transferred into nonsingular standard control problem. Then according to the linear fractional denoting algorithm of the rational function parameter perturbation system, the Linear Fractional Transform （LFT） model of yaw and sway coupled motion is solved, which is used to design the ship steering robust control system. For the ship steering system with the uncertain parameters, the robust control law is designed based on H^∞ μ-synthesis. And the robust performance of the system is analyzed and the simulation validation is made. Simulation results show that the designed control system has excellent control effect and robustness.

关键词： ship steering H^∞ control parameter perturbation robustness

四氧化三铁磁性纳米颗粒人工模拟酶在快速检测二硝基甲苯中的研究及应用

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分析化学 2016年第2期44卷 179-185页

作者：聂冬霞施国跃于妍妍上海市农业科学院农产品质量标准与检测技术研究所华东师范大学化学系徐州医学院药学院

通过共沉淀法制备了具有类过氧化物酶催化活性的四氧化三铁磁性纳米颗粒（Fe;O;MNPs）。研究表明,Fe;O;MNP;可以催化H;O;氧化2,2’-连氮基-双-（3-乙基苯并二氢噻唑啉-6-磺酸）(ABTS)二铵盐,生成有色的氧化态ABTS,同时也可催化H;O;氧化... 详细信息

通过共沉淀法制备了具有类过氧化物酶催化活性的四氧化三铁磁性纳米颗粒（Fe;O;MNPs）。研究表明,Fe;O;MNP;可以催化H;O;氧化2,2’-连氮基-双-（3-乙基苯并二氢噻唑啉-6-磺酸）(ABTS)二铵盐,生成有色的氧化态ABTS,同时也可催化H;O;氧化二硝基甲苯（DNT）的反应,消耗反应物H;O;。基于上述原理,构建了Fe;O;MNP;-ABTS-H;O;-DNT反应体系,用于检测DNT。结果表明,氧化态ABTS在417nm处的吸收值随着DNT含量的增加而降低,与DNT浓度在5×10;.0×10;mol/L范围内呈良好的线性关系,检测限为1.5×10;mol/L（S/N=3）。采用紫外-可见分光光度法对Fe;O;MNP;-ABTS-H;O;-DNT体系的反应机理、反应条件等进行了深入探讨。所建立的硝基苯类化合物含量的比色分析方法简便、快速、灵敏、可靠,对环境水样中硝基苯类化合物的在线监测具有潜在的应用价值。

关键词：二硝基甲苯四氧化三铁磁性纳米颗粒过氧化物模拟酶分光光度法

Silk damping in scalar-induced gravitational waves: a novel probe for new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 79-85页

作者： yan-Heng yu Sai Wang Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences

Silk damping is well known in the study of cosmic microwave background（CMB） and accounts for suppression of the angular power spectrum of CMB on large angular multipoles. In this article, we study the effect of Silk damping on the scalar-induced gravitational waves（SIGWs）. Resulting from the dissipation of cosmic fluid, the Silk damping notably suppresses the energydensity spectrum of SIGWs on scales comparable to a diffusion scale at the decoupling time of weakly-interacting particles. The effect offers a novel observable for probing the underlying particle interaction, especially for those mediated by heavy gauge bosons beyond the standard model of particles. We anticipate that pulsar timing arrays are sensitive to gauge bosons with mass ～10～3-10～4 GeV, while space-and ground-based interferometers to those with mass ～10～7-1012GeV, leading to essential complements to on-going and future experiments of high-energy physics.

关键词： scalar-induced gravitational waves Silk damping new physics

Assessment of prognosis and curative effect in patients with chronic severe hepatitis using the model for end-stage liver disease scores

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Chinese Medical Journal 2006年第2期119卷 148-150页

作者： WU Chi-hong TIAN Geng-shan XU Xiao-yuan yu yan-yan LU Hai-ying Department of Infectious Disease Peking University First Hospital Beijing 100034 China

Severe hepatitis is the most severe liver disease, with poor prognosis and high mortality. We explored the practical use of the model for end-stage liver disease （MELD） on clinical and the molecular adsorbents recirculating system （MARS） on chronic severe hepatitis to predict the short-term prognosis of patients with chronic severe hepatitis using the MELD score and the curative effect of MARS treatment.

关键词： chronic severe hepatitis end-stage liver disease molecular adsorbents recirculating system

Wild-Type KRAS and BRAF Could Predict Response to Cetuximab in Chinese Colorectal Cancer Patients

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Chinese Journal of Cancer Research 2011年第4期23卷 271-275页

作者： Jing Gao, Ting-ting Wang, Jing-wei yu, yan-yan Li, Lin Shen* Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Oncology, Peking University School of Oncology, Beijing Cancer Hospital & Institute, Beijing 100142, China Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Department of Gastrointestinal Oncology Peking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100142 China.

Objective: To analyze the relationship between KRAS, BRAF mutations and the response to Cetuximab in Chinese colorectal cancer patients. Methods: A total of 273 Chinese colorectal cancer patients were evaluated for KRAS and BRAF mutations by Sanger sequencing. Among them, 59 patients with metastatic colorectal cancer (mCRC) were treated with Cetuximab in combination with chemotherapy from August 2005 to July 2009. Statistical analysis was conducted to assess the relationship between KRAS, BRAF mutations and the response or survival of 59 mCRC patients. Results: KRAS and BRAF mutation rates were 38.5% (105/273) and 5.1% (14/273), respectively, and KRAS/BRAF mutations were mutually exclusive. Among 59 patients treated with Cetuximab plus chemotherapy, KRAS and BRAF mutations were identified in 11 and 5 patients, respectively. The response rates and median progression-free survivals (PFS) in KRAS wild-type and mutant patients were 35.4% (17/48) vs. 9.1% (1/11) (P=0.054) and 153 days vs. 99 days (P=0.01), respectively. Also, the response rates and median PFS in BRAF wild-type and mutant patients were 37.2% (16/43) vs. 20% (1/5) (P=0.016) and 138 days vs. 90 days (P=0.036), respectively. Conclusion: Besides KRAS, assessing BRAF mutation should also be required to select patients eligible for Cetuximab. Further prospective evaluation in large samples should be performed to confirm these preliminary findings.

关键词： KRAS BRAF Mutation Cetuximab Colorectal cancer