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Metabolism Study on Tobacco-specific N-Nitrosamines in Rabbit by Solid-phase Extraction and liquid Chromatography-electrospray Ionization-mass Spectrometry Method

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Chinese Chemical Letters 2005年第12期16卷 1633-1636页

作者： Jian Xun ZHANG chen chen li Zheng chen zhi Hua RAO Da Wei WEN Ke An li Hu Wei liU College of Chemistry and Molecular Engineering Peking University Beijing 100871

Metabolism of four tobacco-specific N-nitrosamines （TSNAs）, N＇-nitrosonornicotine （NNN）, N＇-nitrosoanatabine （NAT）, N＇-nitrosoanabasine （NAB） and 4-（methyl nitrosamino）-1- （3-pyridyl）-1-butanone （NNK） was studied by solid-phase extraction （SPE） and liquid chromato- graphy-electrospray ionization-mass spectrometry （LC-ESI-MS）. SPE and LC-ESI-MS method was evaluated to be rapid, simple, sensitive and selective for analysis of TSNAs in rabbit serum. The doses of TSNAs administrated were 4.666 μg/kg and 11.665 μg/kg according to different levels in cigarettes. Metabolic curves of four TSNAs and 4-（methyl nitrosamino）-1-（3-pyridyl）- 1-butanone （NNAL）, the metabolite of NNK, were obtained.

关键词： Tobacco-specific N-nitrosamines metabolism liquid chromatography-electrosprayinterface-mass spectrometry

Using p53-immunostained large specimens to determine the distal intramural spread margin of rectal cancer

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World Journal of Gastroenterology 2006年第10期12卷 1626-1629页

作者： zhi-Zhong Pan De-Sen Wan Chang-Qing Zhang Jian-Yong Shao li-Ren li Gong chen zhi-Wei Zhou Fu-Long Wang Department of Abdominal Surgery Cancer Hospital Sun Yat-Sen University Guangzhou 510060 Guangdong Province China

AIM： To determine the distal intramural spread （DIS） margin of rectal cancer.METHODS： Sixty-one p53-positive specimens of rectal cancer were used. After conventional hematoxylin and eosin （H＆E） staining, the DIS margin of rectal cancer in large specimens was examined by immunohistochemistry. The patients were divided into A, B, C, and D groups. After a long-term follow-up, the survival curves of the four groups were estimated using the life table. RESULTS： Fifty-one of the sixty-one cases （83.6%） had DIS. The extent of DIS ranged 0.11-3.5 cm; meanwhile *** of DIS measured by H＆E staining was 0.13 cm. The significant difference was found between the means （t=5.622, P〈0.0001）. Only 1 of 51 patients had DIS greater than 3 cm. The DIS was less than 1.0 cm in most rectal cancer patients. The long-term results indicated that the survival rate of the patients whose DIS was greater than 1.0 cm was lower than that of the patients whose DIS was less than 0.5 cm. CONCLUSION： Rectal cancer patients with DIS greater than 1.0 cm have poor prognosis.

关键词： Rectal cancer Distal intramural spread p53 Immunohistochemistry Large specimen

Optimization of silicon-on-insulator based optical switch using tapered waveguides

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Optoelectronics Letters 2007年第5期3卷 326-328页

作者： li zhi-yong chen Shao-wu YU Jin-zhong State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing100083 China

Optimized 2×2 switches based on silicon-on-insulator (SOI) were demonstrated. In the design, single mode rib waveguidesand multimode interferences (MMIs) are connected by tapered waveguides to reduce the mode coupling loss between thetwo types of waveguides. The average insertion loss of the switches is about -16.9 dB and the excess loss of one is measuredof -1.3 dB. The worst crosstalk is larger than 25 dB. Experimental results indicate that some of the main characteristics ofoptical switches are improved in the modified design, which is according with theoretic analysis. The novel design can beused to improve the characteristics of optical switch matrixes based on 2×2 switch units.

关键词：光学开关集成电路波导绝缘体

Synthesis of N-Alkylperfluorooctanesulfonamides and Its Derivatives

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有机化学 2003年第Z1期23卷 118-119页

作者： li Yan chen zhi-Qi ZHOU Ye-Bing chen Zu-Xing liU Zhao-Jie Faculty of Chemisty and Material Science Hubei University Wuhan 430062 Institute of Organic Synthesis Central China Normal University Wuhan 430079 Faculty of Chemisty and Material Science Hubei University Wuhan 430062 Faculty of Chemisty and Material Science Hubei University Wuhan 430062 Faculty of Chemisty and Material Science Hubei University Wuhan 430062 Institute of Organic Synthesis Central China Normal University Wuhan 430079

　　N-Alkylperfluorooctanesulfonamide compounds are special fine chemicals, and have been applied in many fields, such as vulcanizing agents for fluoro rubbers, smooth and friction reducing for coatings, fire extinguisher, anticorrosive agents for metals, water- and oil-repellents for leather, textiles and paper, photographic emulsion.[1]……

关键词： vulcanizing agents

Small interfering RNA of cyclooxygenase-2 induces growth inhibition and apoptosis independently of Bcl-2 in human myeloma RPMI8226 cells

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Acta Pharmacologica Sinica 2007年第7期28卷 1031-1036页

作者： Qiu-bai li zhi-chao chen Yong YOU Ping ZOU Department of Hematology,Union Hospital,Tongji Medical College,Huazhong University of Science and Technology,Wuhan 430022,China Department of Hematology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China

Aim:To investigate the effects of small interfering RNA of cyclooxygenase-2(COX-2) on the proliferation and apoptosis of human multiple myeloma RPMI8226cells and its relation with the Bcl-2 family in ***:Transcription andexpression of COX-2 in human myeloma RPMI8226 cells were checked by RT-PCRand Western blot analysis,*** COX-2 siRNA fragment targetingexon 5 of COX-2 gene was transfected into the cells with the Amaxa *** inhibition of cell growth was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium (MTT) *** was estimatedby Annexin-V/propidium iodide double-labeled cytometry and confirmed by termi-nal deoxynucleotidyl transferase-mediated dUTP nick end-labeling ***-2and Bax expression was evaluated by Western blot ***:The COX-2siRNA fragment could be successfully transfected into RPMI8226 cells,whichresulted in the significant inhibition of transcription and expression of COX-2 inthe myeloma *** of the transfected cells was inhibited andapoptosis was induced (6.52%±0.32%,12.53%±2.52%,24.39%±3.51% and36.48%±4.96% for 0,12,24,and 48 h,respectively) in a time-dependent manner(P<0.01).However,the expression of Bcl-2 and Bax in the RPMI8226 cells had nosignificant changes after ***:COX-2 siRNA transfectioncan suppress COX-2 expression in human myeloma RPMI8226 cells,which leadsto growth inhibition and apoptosis independent of Bcl-2.

关键词： RPMI8226 small interfering RNA apoptosis proliferation

A METHOD AND A SOFTWARE FOR CONSTRUCTING F-BY-F RANDOM LOAD SPECTRUM

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Chinese Journal of Aeronautics 1992年第4期 300-304页

作者： li Jian, chen zhi-wei(Beijing Aeronautical Technology Research Center,Beijing,101100,China

The paper presents a method and a software for constructing flight by flight(F-by-F) random load *** on load factors at the centre of gravity measuredin flights,the software creats Markov matrix corresponding to each flight mission afterprocessing the *** statistical averaged Markov matrix is adjusted to ensure anuninterrupted load sequence ***,a sequence of half cycles is drawn from thematrix to construct an F-by-F random load *** drawing method for half-cyclesin the matrix is discussed,and an example of application is given in the paper.

关键词： A METHOD AND A SOFTWARE FOR CONSTRUCTING F-BY-F RANDOM LOAD SPECTRUM

Concurrent hyperglycemia does not influence the long-term prognosis of unresectable hepatocellular carcinomas

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World Journal of Gastroenterology 2003年第8期9卷 1848-1852页

作者： Xiao-Ping li Zhen chen zhi-Qiang Meng Wen-Xia Huang Lu-Ming liu, Department of liver Neoplasms, Cancer Hospital, Fudan University, Shanghai 200032, China Department of liver Neoplasms Cancer Hospital Fudan University Shanghai 200032 China. lxpmy@***

AIM: The association has been established between the disorder of carbohydrate metabolism and liver ***, little is known regarding the impact of concurrent hyperglycemia on prognosis of hepatocellular carcinoma (HCC). The present study aimed at solving this ***: A total of 225 patients included in this study,were admitted from January 1998 to December 2001 for an unresectable HCC proven by histological and imaging examinations. Most of the patients received interventional treatment, radiation and biotherapy. Response was evaluated by computerized tomography (CT) scan conducted 4-6 weeks following completion of the treatment, and then every 3months, Survival was calculated from the beginning of treatment using the Kaplan-Meier method. Pretreatment,treatment and follow-up variables with possible prognostic significance were analyzed. A stepwise multivariate analysis was performed using the Cox regression model, and a prognostic index was ***: No differences were observed in survival parameters between the patients with and without hyperglycemia, median survival times of the patients were being 26±3.46 months and 29.5±2.04 months, respectively, and the 3-year survival rate was 8.36%and 9.62%, respectively. The univariate analysis indicated that there were several survival-associated variables including serum AFP level, clinical stage, Child-Pugh grade,method of treatment, size and number of tumor nodule (s).However, only the clinical stage, Child-Pugh grade and the treatment procedure were proved to be independent prognostic factors in the multivariate ***: This study indicates that hyperglycemia does not influence the long-term prognosis of HCC, and concurrent hyperglycemia should not be considered as an unfavorable prognostic factor during the treatment of patients with HCC.

关键词：肝细胞癌并发症高血糖症预后

Recent Neutronics Analysis for a China ITER HCSB NT-TBM

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2006年第1期 166-167页

作者： ZHANG Guoshu FENG Kaiming li Zengqiang chen zhi YUAN Tao

1 Description of structure, materials and MCNP model Except that height, sub-module numbers of present HCSB TBM increases by 2 times, there are hardly other changes in structure and geometry. Fig.l shows general schematic for 3-D structure of previous 3 X 3 and updated 3 X 6 HCSB TBM structure. Present 3X6 HCSB TBM box is mounted on 1/2 ITER testing port. It is 48.4 cm in width, 66 cm in height, 63 cm in depth, 2 cm of gaps on side faces between frame wall and TBM box. A frame wall thickness around TBM module is 20 cm.

关键词：中子物理学他气冷式固体模式核物理核技术

口泉断裂断层气地球化学变化特征及断层活动性

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地震 2017年第1期37卷 39-51页

作者：王江李营陈志中国地震局地震预测重点实验室中国地震局地震预测研究所北京100036 河北省地震局监测网络中心石家庄050021

2015年对口泉断裂进行了3期断层气地球化学重复观测,分析了中段石井村剖面和北段上皇庄剖面CO_2、Rn、Hg浓度及通量时空变化特征,发现这两条剖面内CO_2、Rn浓度及通量时空变化特征基本一致。石井村剖面CO_2通量、Rn浓度及通量高于上皇... 详细信息

2015年对口泉断裂进行了3期断层气地球化学重复观测,分析了中段石井村剖面和北段上皇庄剖面CO_2、Rn、Hg浓度及通量时空变化特征,发现这两条剖面内CO_2、Rn浓度及通量时空变化特征基本一致。石井村剖面CO_2通量、Rn浓度及通量高于上皇庄剖面。上皇庄剖面Hg浓度及通量3期随时间持续上升。认为口泉断裂断层活动活跃,第四纪活动性中段高于北段,且北段断层活动呈增强趋势。

关键词：断层气CO2 Rn Hg浓度及通量断层活动性口泉断裂