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A Deniable Authenticated Key Agreement Protocol

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Wuhan university Journal of Natural Sciences 2008年第6期13卷 645-650页

作者： TIAN Haibo1,2, CHEN Xiaofeng1,2, ZHANG Fangguo1,2, WEI Baodian1,2 1. School of Information Science and Technology, sun yat-sen university, guangzhou 510006, Guangdong, china 2. Guangdong Key Laboratory of Information Security Technology, sun yat-sen university, guangzhou 510275, Guangdong, china School of Information Science and Technology Sun Yat-Sen University Guangzhou 510006 Guangdong China Guangdong Key Laboratory of Information Security Technology Sun Yat-Sen University Guangzhou 510275 Guangdong China

This paper presents a deniable authenticated key agreement protocol. This protocol can provide an authenticated session key while the sender and the receiver can deny their involvement in such a protocol if the protocol is executed successfully. Then both can deny their transmitted messages protected by the authenticated session key. If this protocol fails, no authenticated session key can be established and no protected messages can be transmitted. The protocol can be proved secure against key compromise impersonation attack. The protocol employs a new method to isolate a session key from confirmation keys.

关键词： deniable authentication key agreement key compromise impersonation

Inactivation gating determines drug potency:a common mechanism for drug blockade of HERG channels

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Acta Pharmacologica Sinica 2004年第5期25卷 12-18页

作者： Bao-feng YANG1, Dong-hui XU2, Chao-qian XU, Zhe LI, Zhi-min DU, Hui-zhen WANG, De-li DONGdepartment of Pharmacology, Harbin Medical university, Harbin 150086, china 2department of Pharmacy, sun yat-sen university, guangzhou 510080, china department of Pharmacology Harbin Medical University department of Pharmacy Sun Yat-sen University

AIM: To determine the mechanisms of interactions between different drugs and HERG channels. METHODS:Various antiarrhythmic (dofetilide, quinidine, azimilide, RP58866) and non-antiarrhythmic (terfenadine, nicotine)agents were used on HERG channels expressed in Xenopus oocyte. Whole-cell voltage-clamp techniques wereused. RESULTS: All drugs produced concentration-dependent block of HERG current. The inhibition was mark-edly facilitated with voltage protocols favoring channel inactivation (eg, less negative holding potentials). Maneu-vers that weakened channel inactivation (eg, elevation of external K+), relieved HERG blockade by all drugs. Moreover,the inhibitory potency was reduced by at least 20-300 fold with varying compounds when rapid C-type inactivationwas removed by a mutation located between the transmembrane domains 5 and 6 (S631A). CONCLUSION: Theinactivation gating of HERG channels determines the blocking potency of drugs. This mechanism might be com-mon to drugs of various classes.

关键词： antiarrhythmic agents potassium channels mutation channel inactivation patch-clamp techniques oocytes Xenopus

Correlation analysis between loss of heterozygosity at chromosome 18q and prognosis in the stage-Ⅱ colon cancer patients

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Chinese Journal of Cancer 2010年第8期29卷 761-767页

作者： Wei Wang1,2, Yuan-Fang Li1,2, Xiao-Wei sun1,2, Gong Chen1,3, You-Qing Zhan1,2, Chun-Yu Huang1,2, De-sen Wan1,3, Zhi-Zhong Pan1,3, Zhi-Wei Zhou1,2 1 State Key Labortary of Oncology in South china, guangzhou, Guangdong 510060, P. R. china 2 department of Gasrtic and Pancreatic Surgery, sun yat-sen university Cancer Center, guangzhou, Guangdong 510060, P. R. china 3 department of Colorectal Surgery, sun yat-sen university Cancer Center, guangzhou, Guangdong 510060, P. R. china department of Gasrtic and Pancreatic Surgery Sun Yat-sen University Cancer Center State Key Labortary of Oncology in South China Guangdong Guangzhou 510060 department of Colorectal Surgery Sun Yat-sen University Cancer Center State Key Labortary of Oncology in South China Guangdong Guangzhou 510060

Background and Objective: Colorectal cancer is one of the most common malignant cancers in the world. Although the clinicopathologic staging is the golden criterion for the prognosis at present, the optimum prognostic criteria for colorectal cancer should be a combination of the clinicopathologic staging and the molecular markers. However, there are currently no molecular markers available for the prognosis of colorectal cancer. Several tumor-suppressor genes associated with colorectal cancer have been mapped at the 18q21-23 region. In this study we detected the frequency of loss of heterozygosity (LOH) at chromosome 18q and investigated the relationship between LOH and clinicopathologic features and its prognostic value for patients with stage Ⅱ colon cancer. Methods: A total of 106 samples of tumor tissues and corresponding normal mucosa from patients with sporadic stage-Ⅱ colon cancer were included in this study. All the samples were formalin-fixed and paraffin-embedded. DNA was extracted from tumor tissues and LOH of D18S474, D18S55, D18S58, D18S61 and D18S64 at chromosome 18q was analyzed using polymerase chain reaction (PCR), polyacrylamide gel-electrophoresis, and DNA sequencing method. Multivariate analysis for association between LOH and prognosis in colon cancer patients was performed with Cox proportional hazards regression model. Results: The median follow-up time was 68 months. For 106 patients, 5-year survival rate was 83.6%, which was associated with age and gross tumor type (P = 0.011 and 0.034, respectively). Among 102 patients who were eligible for LOH information, the overall frequency of LOH is 49.0% (50/102), and that of LOH at 5 microsatellite loci of D18S474, D18S55, D18S58, D18S61, and D18S64 was 30.2% (26/86), 23.4% (18/77), 28.6% (20/70), 35.0% (28/80), and 20.8%(15/72), respectively. The occurrence of LOH was significantly associated with tumor location and histopathologic grade (P = 0.023, 0.016 and 0.005, respectively). LOH was more freq

关键词：大肠癌染色体杂合性预后患者相关分析聚丙烯酰胺凝胶电泳临床病理

Expression of hepatitis B virus surface antigen in 120 Hodgkin's lymphoma patients

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Chinese Journal of Cancer 2010年第8期29卷 735-740页

作者： Miao-Zhen Qiu1,2, Dan-Yun Ruan1,2, Zhi-Qiang Wang1,2, Hui-Yan Luo1,2, Kai-Yuan Teng1,2, Zhong-Jun Xia1,3, Yue Lu1,3, Hui-Qiang Huang1,2, Wen-Qi Jiang1,2, Rui-Hua Xu1,2 1 State Key Laboratory of Oncology in South china, sun yat-sen university Cancer Center, guangzhou, Guangdong 510060, P. R. china 2 department of Medical Oncology, sun yat-sen university Cancer Center, guangzhou, Guangdong 510060, P. R. china 3 department of Hematology Oncology, sun yat-sen university Cancer Center, guangzhou, Guangdong 510060, P. R. china sun yat-sen university Cancer Center State Key Laboratory of Oncology in South China Guangdong Guangzhou 510060

Background and Objective: Little is known about the incidence of hepatitis B virus (HBV) infection in Hodgkin's lymphoma patients. This study was to evaluate the impact of HBV infection on the survival of Hodgkin's lymphoma patient. Methods: Clinical data of 120 Hodgkin's lymphoma patients treated at the sun yat-sen university Cancer Center between January 2004 and October 2007 were collected. The impact of prognostic factors including HBV infection on survival was examined by univariate and multivariate analyses. A log-rank test was used for univariate analysis and the Cox proportional hazards regression model was used for multivariate analysis. Results: Of the 120 patients, 18 (15.0%) were hepatitis B virus surface antigen (HBsAg)-positive. The HBsAg-positive patients had lower 5-year survival rate than did the HBsAg-negative ones (66.9% vs. 91.3%, P = 0.006). When the patients were divided into early-stage (Ⅰ+Ⅱ) and advanced-stage (Ⅲ+Ⅳ) groups, the 5-year survival rate was significantly different between the HBsAg-positive and -negative patients in early-stage group (64.8% vs. 96.0%, P < 0.001), while not significantly different in advanced-stage group (75.0% vs. 84.8%, P=0.667). Both univariate and multivariate analyses showed that radiotherapy and HBV infection were independent prognosis factors for the patients with early-stage Hodgkin's lymphoma (P=0.006 and 0.014, respectively). Conclusions: The incidence of HBV infection is similar between Hodgkin's lymphoma patients and normal population. HBV infection is an independent prognosis factor for survival in the patients with early-stage Hodgkin's lymphoma.

关键词：乙肝病毒表面抗原淋巴瘤患者乙肝表面抗原多因素分析金病毒感染肝炎病毒

Research on Public Participation and Information Publicity in Strategic Environmental Assessment

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 40-46页

作者： Gao Changbo 1,2, Mo Chuangrong 1, Chen Xingeng 1, Zhang Shixi 1 & sun Yanjun 1 1.School of Environmental Sciences and Engineering, sun yat-sen university, guangzhou 510275, china 2.Guangdong Industry Technical College, guangzhou 510300, china School of Environmental Sciences and Engineering Sun Yat-sen University Guangzhou 510275 China Guangdong Industry Technical College Guangzhou 510300 China

It has been generally recognized that strategic environmental assessment integrates environment and development into decision-making and becomes an important decision-making tool for implementing sustainable development. This paper firstly introduces the relationships of SEA, public participation(PP)and information publicity(IP),then discusses the key parts in enforcing the effective process of PP: They are the methods for how to make sufficient information open (What), when to implement PP (When), who will determinate the public (Who), and how to make the models of PP (How). Six cases are compared and analyzed. At last, ways to improve the effectiveness of PP in china is also presented.

关键词： strategic environmental assessment (SEA) public participation (PP) information publicity (IP) effectiveness

Experimental study of gene therapy with angiostatin gene in pancreatic cancer

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Hepatobiliary & Pancreatic Diseases International 2002年第3期1卷 452-457页

作者： Sheng-Li Nie Shi-Zhen Yuan the department of Gastroenterology, sun yat-sen Memorial Hospital, Medical College, sun yat-sen university, guangzhou 510120, china department of Gastroenterology Sun Yat-Sen Memorial Hospital Medical College Sun Yat-Sen University Guangzhou 510120 China. victorynie@***

Objective: To study the effects of angiostatin (AS) gene mediated by liposome on human pancreatic cancer cell line SW1990. Methods: Angiostatin gene was cloned into the eu- karyotic expression vector pRC/CMV. The recombi- nant of pRC/CMV-AS was introduced into the pan- creatic cancer cell line, SW1990. The mechanism of anti-tumor was studied and tested. Results: The eukaryotic expression vector pRC/ CMV-AS was identified by the restriction digest. pRC/CMV-AS was stably integrated into the target cells and expressed by Western blot and drug-sensi- tivity tests, and inhibited the vascular endothelial cells proliferation in vitro. In addition, the effects of the angiostatin vector on reducing the volume of tumors implanted in nude mouse models were also noted. Conclusion: This study demonstrated that the recom- binant pRC/CMV-AS mediated by liposome may play a potential role in the treatment of pancreatic cancer in the future.

关键词： angiostatin gene therapy pancreatic cancer vector angiogenesis liposome antiangiogenesis dormancy therapy

Tetracycline-controlled transcriptional regulation systems: countermeasures to eliminate basal transgene leaks in Tet-based systems

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Progress in Natural Science:Materials International 2007年第1期17卷 11-19页

作者： XIAO Dong, sun Yan, GU Weiwang and CHEN Xigu ( Center of Experimental Animals and Institute of Comparative Medicine, Southern Medical university, guangzhou 510515, china Center of Experimental Animals, sun yat-sen university, guangzhou 510080, china) [a]Center of Experimental Animals and Institute of Comparative Medicine Southern Medical University Guangzhou China [b]Center of Experimental Animals Sun Yat-sen University Guangzhou China

To analyze the function of any given transgene(s) accurately in transgenic mice, and to produce credible transgenic animal models of various human diseases (precisely and realistically mimicking disease states), it is critical to be able to control gene expression in the animals conditionally. The ability to switch gene expression "on" or "off" in the restricted cells or tissue(s) at specific time(s) allows unprecedented flexibility for exploring gene function(s) in both the health and the disease. Pioneering work on inducible transgene expression has led to the development of a wide variety of controlled gene expression systems that meet this criterion. Among them, the tetracycline-inducible systems (e.g. Tet-off and Tet-on) have been widely, frequently and successfully employed in vitro and in vivo. These systems, however, are not always tight but leaky; sometimes the leakage is significant. In some circumstances, the resulting leak is acceptable, but in others, it is more problematic. Though these systems face this disadvantage, i. e. basal transgene leakage in vitro and in vivo, several approaches, including using improved versions (e.g. rtTA2S-M2 and rtTA2S-S2) of rtTA, tetracycline-controlled transcriptional silencer (tTS), an "ideal" minimal promoter in responsive components or combinations thereof, have been developed to avoid this limitation effectively. In this review we discuss the countermeasures available to eliminate basal transgene leakage from Tet-based systems.

关键词： tetracycline inducible system transgenic mice leaky expression transcriptional silencer.

Studies on rickettsia-like organism (RLO) disease of tropical marine pearl oyster-Epidemiological investigation of RLO disease in juvenile populations of maricultured Pinctada maxima

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Acta Oceanologica Sinica 2003年第3期22卷 421-435页

作者： Xinzhong Wu , Dengfeng Li, Jinpei Pan, Jingbo Jiang College of Animal Sciences,Zhejiang university,Hangzhou 310029,china. Email: wuxz@zju.edu.cnSouth china Sea Institute of Oceanology, Chinese Academy of Sciences,guangzhou 510301,chinaSchool of Life Sciences,sun yat-sen university,guangzhou 510275,china Zhejiang Univ Coll Anim Sci Hangzhou 310029 Peoples R China Chinese Acad Sci S China Sea Inst Oceanol Guangzhou 510301 Peoples R China sun yat sen Univ Sch Life Sci Guangzhou 510275 Peoples R China

The death which occurred in juvenile population was a severe problem in the course ofPinctada maxima artificial culture. With the methods of field investigation, histological study and statistic analyses, the epidemiological study was carried out on the disease and death in juvenile populations of Pinctada maxima in the Xinying Pearl Oyster Mariculture Farm of Lingao County (for the A, B and C batches of cultured juveniles hanged in the sea) and the Xincun Pearl Oyster Mariculture Farm of Lingshui County (for the D batch of cultured juvenile hanged in the pond), Hainan Province from November 1993 to April *** results show that the deaths which occurred in juvenile populations of Pinctada maxima presented an outbreak pattern. The peak of mortality rates, in general, occurred in 4-to 6-month old pearl oyster juveniles, and the mortality rates gradully declined with the extention of pearl oyster age after cul-turing 8 months. The correlation between the mortality rates of juvenile populations and mean body lengths of juvenile populations show that the mortality rate become higher under 4 cm of mean body lengths of juvenile population and become obvious declined over 5 cm of mean body lengths. The peak of mortality rate occurred in 1-3 cm of mean body lengths. The results of histological observation showed that rickettsia-like organism inclusions were common, histological widespread infective agent among every batches (A, B, C and D) of cultured juvenile populations. The mean severity indices (SI) of rickettsia-like organism (RLO) infection were positively correlated with mortality rates of juvenile populations. After or within every peaks of RLO infection were all accompanied with the peaks of mortality rates of host populations and the mortality rates declined with decreased RLO infection. So the evidences of histological observation and epidemiology in this study indicated that rickettsia-like organism (RLO) may be as an important pathogenic organism of disease

关键词： Pinctada maxima rickettsia-like organism epidemiology juvenile population

CHEBYSHEV FINITE SPECTRAL METHOD FOR 2-D EXTENDED BOUSSINESQ EQUATIONS

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Journal of Hydrodynamics 2011年第1期23卷 1-11页

作者： LI Yok-sheung ZHAN Jie-min, SU Wei department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China

In this article,an accurate Chebyshev finite spectral method for the 2-D extended Boussinesq equations is *** method combines the advantages of both the finite difference and spectral *** Adams-Bashforth predictor and the fourth-order Adams-Moulton corrector are adopted for the numerical solution of the governing differential *** efficient wave absorption strategy is also proposed to effectively absorb waves at outgoing wave boundaries and reflected waves from the interior of the computational domain due to barriers and bottom slopes at the incident wave boundary to avoid contamination of the specified incident wave *** proposed method is verified by a case where experimental data are available for comparison for both regular and irregular *** case is wave diffraction over a shoal reported by Vincent and *** results agree very well with the corresponding experimental data.

关键词： Chebyshev polynomial finite spectral method irregular waves