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Establishment of cell clones with different metastatic potential from the metastatic hepatocellular carcinoma cell line MHCC97 被引量:112
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作者 Yan Li Zhao-You Tang Sheng-Long Ye Yin-Kun Liu Jie Chen Qiong Xue Jun Chen Dong-Mei Gao Wei-Hua Bao Liver Cancer Institute and Zhongshan Hospital of Fudan University (Former Liver Cancer Institute of Shanghai Medical University),Shanghai 200032,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第5期630-636,共7页
AIM: To establish clone cells with different metastatic potential for the study of metastasis-related mechanisms. METHODS: Cloning procedure was performed on parental hepatocellular carcinoma (HCC) cell line MHCC97, a... AIM: To establish clone cells with different metastatic potential for the study of metastasis-related mechanisms. METHODS: Cloning procedure was performed on parental hepatocellular carcinoma (HCC) cell line MHCC97, and biological characteristics of the target clones selected by in vivo screening were studied. RESULTS: Two clones with high (MHCC97-H) and low (MHCC97-L) metastatic potential were isolated from the parent cell line. Compared with MHCC97-L, MHCC97-H had smaller cell size (average cell diameter 43 microm vs 50 microm) and faster in vitro and in vivo growth rate (tumor cell doubling time was 34.2h vs 60.0h). The main ranges of chromosomes were 55-58 in MHCC97-H and 57-62 in MHCC97-L. Boyden chamber in vitro invasion assay demonstrated that the number of penetrating cells through the artificial basement membrane was (37.5 +/- 11.0) cells/field for MHCC97-H vs (17.7 +/- 6.3)/field for MHCC97-L. The proportions of cells in G0-G1 phase, S phase, and G2-M phase for MHCC97-H/MHCC97-L were 0.56/0.65, 0.28/0.25 and 0.16/0.10, respectively, as measured by flow cytometry. The serum AFP levels in nude mice 5wk after orthotopic implantation of tumor tissue were (246 +/- 66) microg.L(-1) for MHCC97-H and (91 +/- 66) microg.L(-1) for MHCC97-L. The pulmonary metastatic rate was 100% (10/10) vs 40% (4/10). CONCLUSION: Two clones of the same genetic background but with different biological behaviors were established, which could be valuable models for investigation on HCC metastasis. 展开更多
关键词 ALbUMINS Animals Carcinoma Hepatocellular Cell Division Chromosomes Clone Cells Flow Cytometry Hepatitis b Hepatitis b surface Antigens Hepatitis b virus purification Humans Keratin Liver Liver Neoplasms Experimental Male MICE Mice Inbred bALb C Mice Nude Neoplasm Invasiveness Research Support Non-U.S. Gov't Tumor Cells Cultured Virus Integration ALPHA-FETOPROTEINS
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Effects of hepatitis B virus infection on human sperm chromosomes 被引量:52
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作者 Jian-MinHuang Tian-HuaHuang +6 位作者 Huan-YingQiu Xiao-WuFang Tian-GangZhuang Hong-XiLiu Yong-HuaWang, Li-ZhiDeng Jie-WenQiu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2003年第4期736-740,共5页
AIM: To evaluate the level of sperm chromosome aberrations in male patients with hepatitis B, and to directly detect whether there are HBV DNA integrations in sperm chromosomes of hepatitis B patients.METHODS: Sperm c... AIM: To evaluate the level of sperm chromosome aberrations in male patients with hepatitis B, and to directly detect whether there are HBV DNA integrations in sperm chromosomes of hepatitis B patients.METHODS: Sperm chromosomes of 14 tested subjects (5healthy controls, 9 patients with HBV infection, including 1with acute hepatitis B, 2 with chronic active hepatitis B, 4with chronic persistent hepatitis B, 2 chronic HBsAg carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free golden hamster ova and human spermatozoa, and the frequencies of aberration spermatozoa were compared between subjects of HBV infection and controls. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes.RESULTS: The total frequency of sperm chromosome aberrations in HBV infection group (14.8%, 33/223) was significantly higher than that in the control group (4.3%,5/116). Moreover, the sperm chromosomes in HBV infection patients commonly presented stickiness, clumping, failure to staining, etc, which would affect the analysis of sperm chromosomes. Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis. In 9 (9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots, others presented 2 to 4signals. There was significant difference of fluorescence intensity among the signal spots. The distribution of signal sites among chromosomes was random.CONCLUSION: HBV infection can bring about mutagenic effects on sperm chromosomes. Integrations of viral DNA into sperm chromosomes which are multisites and nonspecific, can further increase the instability of sperm chromosomes. This study suggested that HBV infection can create extensively hereditary effects by alteration genetic constituent and/or induction chromosome aberrations, as well as t 展开更多
关键词 ADULT Chromosomes Human DNA Viral Hepatitis b Antigens Hepatitis b surface Antigens Hepatitis b Chronic Humans In Situ Hybridization Fluorescence KARYOTYPING Male Reference Values Research Support Non-U.S. Gov't SEMEN SPERMATOZOA
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Transformation of hepatitis B serologic markers in babies born to hepatitis B surface antigen positive mothers 被引量:40
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作者 Jian-SheWang HuiChen Qi-RongZhu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第23期3582-3585,共4页
AIM:To better understand the clinical significance of hepatitis B seroiogic markers in babies born to hepatitis B surface antigen (HBsAg) positive mothers, the incidence of maternal seroiogic markers of hepatitis B vi... AIM:To better understand the clinical significance of hepatitis B seroiogic markers in babies born to hepatitis B surface antigen (HBsAg) positive mothers, the incidence of maternal seroiogic markers of hepatitis B via placenta and its transformation in these babies were investigated. METHODS: Mothers with positive HBsAg were selected in the third trimester of pregnancy. Their babies received immunoprophylaxis with hepatitis B immunoglobulin and hepatitis B vaccine after birth, and were consecutively followed up for hepatitis B seroiogic markers and HBV DNA at birth, mo 1, 4, 7, 12, and 24. RESULTS: Forty-two babies entered the study, including 16 born to hepatitis B e antigen (HBeAg)-positive HBsAg carrier mothers and 26 to HBeAg-negative HBsAg carrier mothers. Apart from four babies born to HBeAg-positive carrier mothers and demonstrated persistent positive HBeAg eventually became HBV carriers, all other babies developed anti-HBs before 12 mo of age. Among the other 12 babies born to HBeAg-positive carrier mothers, HBeAg was detected in 7 at birth, in 4 at mo 1, and in none of them thereafter. No antibody response to the transplacental HBeAg was detected. Among the babies born to HBeAg-negative carrier mothers, anti-HBe was detected 100% at birth and mo 1, in 88.5% at mo 4, in 46.2% at mo 7, in 4.2% at mo 12 and none in mo 24. Among all the immunoprophylaxis-protected babies born to either HBeAg-positive or HBeAg-negative carrier mothers, anti-HBc was detected in 100% at birth, mo 1 and mo 4, in 78.9% at mo 7, in 36.1% at mo 12 and in none at mo 24. CONCLUSION: HBeAg can pass through human placenta from mother to fetus and become undetectable before 4 mo of age, but no antibodies response to the transplacental HBeAg can be detected till mo 24 in the immunoprophylaxis-protected babies. The sole existence of anti-HBe before 1 year of age or anti-HBc before 2 years of age in babies born to HBsAg carrier mothers may simply represent the transplacental maternal antibodies, instead of indicators of HBV infection stat 展开更多
关键词 Hepatitis b e antigen Hepatitis b e antibody Hepatitis b Chronic Maternal-infantile transmission Hepatitis b surface antigen Children
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Add-on pegylated interferon augments hepatitis B surface antigen clearance vs continuous nucleos(t)ide analog monotherapy in Chinese patients with chronic hepatitis B and hepatitis B surface antigen≤1500 IU/mL:An observational study 被引量:35
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作者 Feng-Ping Wu Ying Yang +7 位作者 Mei Li Yi-Xin Liu Ya-Ping Li Wen-Jun Wang Juan-Juan Shi Xin Zhang Xiao-Li Jia Shuang-Suo Dang 《World Journal of Gastroenterology》 SCIE CAS 2020年第13期1525-1539,共15页
BACKGROUND Nucleos(t)ide analog(NA)has shown limited effectiveness against hepatitis B surface antigen(HBsAg)clearance in chronic hepatitis B(CHB)patients.AIM To evaluate the efficacy and safety of add-on peginterfero... BACKGROUND Nucleos(t)ide analog(NA)has shown limited effectiveness against hepatitis B surface antigen(HBsAg)clearance in chronic hepatitis B(CHB)patients.AIM To evaluate the efficacy and safety of add-on peginterferonα-2a(peg-IFNα-2a)to an ongoing NA regimen in CHB patients.METHODS In this observational study,195 CHB patients with HBsAg≤1500 IU/m L,hepatitis B e antigen(HBeAg)-negative(including HBeAg-negative patients or HBeAg-positive patients who achieved HBeAg-negative after antiviral treatment with NA)and hepatitis B virus-deoxyribonucleic acid<1.0×10^2 IU/mL after over 1 year of NA therapy were enrolled between November 2015 and December2018 at the Second Affiliated Hospital of Xi'an Jiaotong University,China.Patients were given the choice between receiving either peg-IFNα-2a add-on therapy to an ongoing NA regimen(add-on group,n=91)or continuous NA monotherapy(monotherapy group,n=104)after being informed of the benefits and risks of the peg-IFNα-2a therapy.Total therapy duration of peg-IFNα-2a was 48 wk.All patients were followed-up to week 72(24 wk after discontinuation of peg-IFNα-2a).The primary endpoint was the proportion of patients with HBsAg clearance at week 72.RESULTS Demographic and baseline characteristics were comparable between the two groups.Intention-to-treatment analysis showed that the HBsAg clearance rate in the add-on group and monotherapy group was 37.4%(34/91)and 1.9%(2/104)at week 72,respectively.The HBsAg seroconversion rate in the add-on group was 29.7%(27/91)at week 72,and no patient in the monotherapy group achieved HBsAg seroconversion at week 72.The HBsAg clearance and seroconversion rates in the add-on group were significantly higher than in the monotherapy group at week 72(P<0.001).Younger patients,lower baseline HBsAg concentration,lower HBsAg concentrations at weeks 12 and 24,greater HBsAg decline from baseline to weeks 12 and 24 and the alanine aminotransferase≥2×upper limit of normal during the first 12 wk of therapy were strong predictors of HBsAg clearance i 展开更多
关键词 Chronic HEPATITIS b Peginterferonα-2a Nucleos(t)ide ANALOG HEPATITIS b surface ANTIGEN CLEARANCE HEPATITIS b surface ANTIGEN seroconversion ADD-ON therapy
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Molecular characteristics and stages of chronic hepatitis B virus infection 被引量:33
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作者 Ying-Hui Shi Chang-He Shi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第25期3099-3105,共7页
Hepatitis B virus (HBV) is a common viral pathogen that causes a substantial health burden worldwide. Remarkable progress has been made in our understanding of the natural stages of chronic HBV infection. A dynamic ba... Hepatitis B virus (HBV) is a common viral pathogen that causes a substantial health burden worldwide. Remarkable progress has been made in our understanding of the natural stages of chronic HBV infection. A dynamic balance between viral replication and host immune response is pivotal to the pathogenesis of liver disease. Knowledge of the HBV genome organization and replication cycle can unravel HBV genotypes and molecular variants, which contribute to the heterogeneity in outcome of chronic HBV infection. Most HBV infections are spontaneously resolved in immunocompetent adults, whereas they become chronic in most neonates and infants at a great risk of developing complications such as cirrhosis and hepatocellular carcinoma (HCC). Those with chronic HBV infection may present in one of the four phases of infection: immune tolerance, immune clearance [hepatitis B eantigen (HBeAg)-positive chronic hepatitis B (CHB)], inactive carrier state, and reactivation (HBeAg-negative CHB). Understanding the dynamic nature of chronic HBV infection is crucial in the management of HBV carriers. Long-term monitoring and optimal timing of antiviral therapy for chronic HBV infection help to prevent progression of HBV-related liver disease to its later stage, particularly in patients with higher risk markers of HCC, such as serum DNA concentration, HBeAg status, serum aminotransferase, HBV genotypes, and pre-core or core mutants. 展开更多
关键词 Hepatitis b virus PATHOLOGY Immune tolerance Immune clearance Inactive hepatitis b surface antigen carriers REACTIVATION T-cell response CYTOKINES
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粗糙表面接触的弹性、弹塑性、塑性分形模型 被引量:23
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作者 朱育权 马保吉 姜凌彦 《西安工业学院学报》 2001年第2期150-157,共8页
在M B模型的基础上考虑了材料的弹塑性变形过程和接触界面摩擦的作用建立了粗糙表面接触的弹性、弹塑性、塑性分形模型 .分析表明 ,M B模型适用于理想的弹性 塑性材料 ;摩擦副接触界面间的摩擦力对接触状态有较大的影响 ,摩擦力的作用... 在M B模型的基础上考虑了材料的弹塑性变形过程和接触界面摩擦的作用建立了粗糙表面接触的弹性、弹塑性、塑性分形模型 .分析表明 ,M B模型适用于理想的弹性 塑性材料 ;摩擦副接触界面间的摩擦力对接触状态有较大的影响 ,摩擦力的作用使临界弹性接触面积增大 ,从而增大了弹塑性和塑性变形的可能性以及实际接触面积中弹塑性和塑性接触面积的比例 ;材料的应变硬化程度对接触状态有一定的影响 ,硬化程度越高 ,接触状态越趋于弹性接触 ,硬化指数越大 ,硬化程度越弱 。 展开更多
关键词 粗糙表面 接触 分形 磨擦 M-b模型 弹性 弹塑性
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B样条曲线的节点插入问题及两个新算法 被引量:21
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作者 秦开怀 关右江 《计算机学报》 EI CSCD 北大核心 1997年第6期556-561,共6页
Boehm算法和Oslo算法是B样条曲线的节点插入的经典算法.它们可以有效地将节点插入到端点插值(Endnoint-interpolating)B样条曲线.但是,对于其它的B样条曲线而言,当插入靠近节点矢量两端附近的... Boehm算法和Oslo算法是B样条曲线的节点插入的经典算法.它们可以有效地将节点插入到端点插值(Endnoint-interpolating)B样条曲线.但是,对于其它的B样条曲线而言,当插入靠近节点矢量两端附近的节点时,所有的经典算法都将出错.本文提出了两个节点插入新算法.它们可以解决节点插入的经典算法中的问题,能够将任意节点插入各种B样条曲线之中.它们的另一个重要用途是可以用于各种B样条曲线的升阶. 展开更多
关键词 b样条 节点插入 升阶 曲线 曲面 算法
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3维植物叶片精确建模和绘制技术研究 被引量:25
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作者 陆声链 郭新宇 李长锋 《中国图象图形学报》 CSCD 北大核心 2009年第4期731-737,共7页
准确、灵活的叶片模型对植物建模具有重要的意义,但目前大部分植物叶片曲面模型没有提供足够的准确性和细节描述。为了给生成准确、细致的叶片几何模型提供灵活的方法,即首先利用B样条曲线来描述叶片的边缘轮廓和主脉;然后用Delaunay三... 准确、灵活的叶片模型对植物建模具有重要的意义,但目前大部分植物叶片曲面模型没有提供足够的准确性和细节描述。为了给生成准确、细致的叶片几何模型提供灵活的方法,即首先利用B样条曲线来描述叶片的边缘轮廓和主脉;然后用Delaunay三角化方法对叶片曲面进行网格化;最后通过改进Loop细分规则的自适应细分方法来优化叶片曲面,从而为植物叶片提供了一种灵活的3维几何造型描述方法。由于B样条曲线能够很好地描述大部分植物叶子的轮廓,Delaunay三角化方法的使用又解决了包含多个裂片的叶片曲面的网格化问题,而自适应曲面细分方法则不仅使得生成的空间曲面具有更高的光滑度,同时可使得生成的叶片曲面能够进行卷曲变形。实验结果充分表明,该方法是有效的。 展开更多
关键词 形态建模 3维植物叶片 b样条 细分曲面
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Preliminary results of Thymosin-a1 versus interferon-α treatment in patients with HBeAg negative and serum HBV DNA positive chronic hepatitis B 被引量:22
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作者 Lin Zhuang Jing You Bao Zhang Tang Su Ying Ding Kui Hua Yan Dan Peng Yan Mei Zhang Lu Zhang ~1Department of Hepatology,Kunming Third Municipal Peoples Hospital,Kunming 650041,Yunnan Province,China ~2Department of Infectious Diseases,The First Affiliated Hospital of Kunming Medical College,Kunming 650032,Yunnan Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期407-410,共4页
INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 a... INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer . 展开更多
关键词 hepatitis b hepatitis b surface antigens INTERFERON-Α thymosin-a1 hepatitis b E antigens SEROLOGY
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Effect of delivery mode on maternal-infant transmission of hepatitis B virus by immunoprophylaxis 被引量:23
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作者 王建设 朱启镕 张秀珍 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第10期1510-1512,共3页
OBJECTIVE: To study the effect of different delivery modes on immunoprophylaxis efficacy so as to clarify whether or not cesarean section reduces immunoprophylaxis failure. METHODS: Mothers with positive hepatitis B s... OBJECTIVE: To study the effect of different delivery modes on immunoprophylaxis efficacy so as to clarify whether or not cesarean section reduces immunoprophylaxis failure. METHODS: Mothers with positive hepatitis B surface antigen (HBsAg) were selected in the third trimester of pregnancy. Their babies were inoculated with hepatitis B immunoglobulin at birth and hepatitis B vaccine at 1, 2 and 7 months of age. HBsAg and its antibodies (anti-HBs) were tested at 1, 4, 7, and 12 months of age, then followed up yearly. RESULTS: A total of 301 babies entered the study, including 144 born by normal spontaneous vaginal delivery, 40 by obstetric forceps or vacuum extraction, and 117 by cesarean section. The incidence of mother's HBeAg positivity or baby's gender constitution was comparable between the three groups. There were no significant differences in the positive rate of anti-HBs or HBsAg at follow-up periods among the three groups. At 12 months of age, anti-HBs could be detected in 78.9% of the babies born by normal vaginal delivery, 84.6% of the babies by forceps or vacuum extraction, and 86.4% of the babies by cesarean section. The positive rate of HBsAg was 8.1%, 7.7%, 9.7%, and chronic HBV infection incidence was 7.3%, 7.7%, 6.8% respectively. CONCLUSIONS: There are no significant effects of delivery mode on the interruption of HBV maternal-baby transmission by immunoprophylaxis. Cesarean section does not reduce the incidence of immunoprophylaxis failure. 展开更多
关键词 Cesarean Section Disease Transmission Vertical Female Hepatitis b Hepatitis b Antibodies Hepatitis b surface Antigens Hepatitis b Vaccines Humans IMMUNOGLObULINS PREGNANCY
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An overview of occult hepatitis B virus infection 被引量:22
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作者 Zeinab Nabil Ahmed Said 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第15期1927-1938,共12页
Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replic... Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome. 展开更多
关键词 Hepatitis b virus Occult infection Occult hepatitis b virus infection Occult hepatitis b Chronic liver disease Hepatocellular carcinoma Hepatitis b surface antigen
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Hepatitis B surface antigen clearance in inactive hepatitis B surface antigen carriers treated with peginterferon alfa-2a 被引量:20
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作者 Ming-Hui Li Yao Xie +11 位作者 Lu Zhang Yao Lu Ge Shen Shu-Ling Wu Min Chang Cai-Qin Mu Lei-Ping Hu Wen-Hao Hua Shu-Jing Song Shu-Feng Zhang Jun Cheng Dao-Zhen Xu 《World Journal of Hepatology》 CAS 2016年第15期637-643,共7页
AIM: To examine the association between interferon(IFN) therapy and loss of hepatitis B surface antigen(HBs Ag) in inactive HBs Ag carriers. METHODS: This was a retrospective cohort study in inactive HBs Ag carriers, ... AIM: To examine the association between interferon(IFN) therapy and loss of hepatitis B surface antigen(HBs Ag) in inactive HBs Ag carriers. METHODS: This was a retrospective cohort study in inactive HBs Ag carriers, who were treatment-naive, with a serum HBs Ag level < 100 IU/m L and an undetectable hepatitis B virus(HBV) DNA level(< 100 IU/m L). All the 20 treated patients received subcutaneous PEG-IFN alfa-2a 180 μg/wk for 72 wk and were then followed for 24 wk. There were 40 untreated controls matched with 96 wk of observation. Serum HBs Ag, HBV DNA, and alanine aminotransferases were monitored every 3 mo in the treatment group and every 3-6 mo in the control group. RESULTS: Thirteen(65.0%) of 20 treated patients achieved HBs Ag loss, 12 of whom achieved HBs Ag seroconversion. Mean HBs Ag level in treated patients decreased to 6.69 ± 13.04 IU/m L after 24 wk of treatment from a baseline level of 26.22 ± 33.00 IU/m L. Serum HBV DNA level remained undetectable(< 100 IU/m L) in all treated patients during the study. HBs Ag level of the control group decreased from 25.72 ± 25.58 IU/m L at baseline to 17.11 ± 21.62 IU/m L at week 96(P = 0.108). In the control group, no patient experienced HBs Ag loss/seroconversion, and two(5.0%) developed HBV reactivation.CONCLUSION: IFN treatment results in HBs Ag loss and seroconversion in a considerable proportion of inactive HBs Ag carriers with low HBs Ag concentrations. 展开更多
关键词 Chronic hepatitis b surface antigen carriers Inactive hepatitis b surface antigen carriers INTERFERON Peginterferon alfa-2a Hepatitis b surface antigen loss/ seroconversion
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NURBS曲面G^1光滑拼接算法 被引量:11
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作者 周西军 杨海成 《计算机辅助设计与图形学学报》 EI CSCD 1996年第3期227-233,共7页
非均匀有理B样条(NURBS)曲线、曲面造型方法,是当前CAD/CAM领域研究热点之一,大量的基于NURBS的实用造型系统得到发展。对NURBS而言,虽然具有参数连续性,但为了实用需要,仍需构造具有一定光滑程度的合成... 非均匀有理B样条(NURBS)曲线、曲面造型方法,是当前CAD/CAM领域研究热点之一,大量的基于NURBS的实用造型系统得到发展。对NURBS而言,虽然具有参数连续性,但为了实用需要,仍需构造具有一定光滑程度的合成曲面,满足局部设计和修改的目的。本文给出了实用的具有二次公共边界曲线的NURBS曲面片G1光滑拼接条件,得到了相应控制顶点、权系数的具体算法;对于一个已知NURBS曲面,构造另一个NURBS曲面,使其达到G1拼接是简单易行的。 展开更多
关键词 曲面造型 b样条 几何连续 CAD CAM
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Early Serum HBsAg Kinetics as Predictor of HBsAg Loss in Patients with HBeAg-Negative Chronic Hepatitis B after Treatment with Pegylated Interferonα-2a 被引量:18
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作者 Minghui Li Lu Zhang +7 位作者 Yao Lu Qiqi Chen Huihui Lu Fangfang Sun Zhan Zeng Gang Wan Linqing Zhao Yao Xie 《Virologica Sinica》 SCIE CAS CSCD 2021年第2期311-320,共10页
Hepatitis B surface antigen(HBsAg)loss is an ideal treatment endpoint for patients with chronic hepatitis B(CHB).We investigated the predictive value of on-treatment HBsAg levels for HBsAg loss in hepatitis B e antige... Hepatitis B surface antigen(HBsAg)loss is an ideal treatment endpoint for patients with chronic hepatitis B(CHB).We investigated the predictive value of on-treatment HBsAg levels for HBsAg loss in hepatitis B e antigen(HBe Ag)-negative CHB patients who received 120-week PEG-IFNα-2a treatment.Serum HBV DNA,HBsAg,and anti-HBs levels were assayed at baseline and every 3 months during the treatment.Of 81 patients,12 achieved HBsAg loss,20 achieved HBsAg\100 IU/mL,and 49 maintained HBs Ag C 100 IU/mL.HBsAg loss rate was only 3.7%at 48 weeks,while it reached to 11.1%and 14.8%after treatment of 96 weeks and 120 weeks.The cutoff HBs Ag levels at 12 weeks predicting HBsAg loss at 96 weeks and 120 weeks of treatment were 400 IU/mL and 750 IU/mL,with AUC 0.725 and 0.722,positive predictive value(PPV)29.41%and 30.56%,and negative predictive value(NPV)93.75%and 97.78%,respectively.The cutoff HBsAg levels at 24 weeks predicting HBsAg loss at 96 weeks and 120 weeks of treatment were 174 IU/m L and 236 IU/mL respectively,with AUC 0.925 and 0.922,PPV 40.0%and 46.15%,and both NPV 100%.The predictive ability of the cutoff HBsAg levels at 24 weeks was better than that at 12 weeks for HBs Ag loss at either 96 or 120 weeks(χ~2=3.880,P=0.049 andχ~2=4.412,P=0.036).These results indicate that extended therapy is critical to HBsAg loss in HBe Ag-negative CHB patients during PEG-IFN treatment,and the HBsAg level at 24 weeks can be used to predict HBsAg loss during tailoring PEG-IFN therapy. 展开更多
关键词 Chronic hepatitis b(CHb) Hepatitis b surface antigen(HbsAg) Pegylated interferon HbsAg loss HbeAg negative
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Occult hepatitis B virus and hepatocellular carcinoma 被引量:16
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作者 Teresa Pollicino Carlo Saitta 《World Journal of Gastroenterology》 SCIE CAS 2014年第20期5951-5961,共11页
Occult hepatitis B virus(HBV)infection(OBI)is a challenging pathobiological and clinical issue that has been widely debated for several decades.By definition,OBI is characterized by the persistence of HBV DNA in the l... Occult hepatitis B virus(HBV)infection(OBI)is a challenging pathobiological and clinical issue that has been widely debated for several decades.By definition,OBI is characterized by the persistence of HBV DNA in the liver tissue(and in some cases also in the serum)in the absence of circulating HBV surface antigen(HBsAg).Many epidemiological and molecular studies have indicated that OBI is an important risk factor for hepatocellular carcinoma(HCC)development.OBI may exert direct pro-oncogenic effects through the activation of the same oncogenic mechanisms that are activated in the course of an HBsAg-positive infection.Indeed,in OBI as in HBV-positive infection,HBV DNA can persist in the hepatocytes both integrated into the host genome as well as free episome,and may maintain the capacity to produce proteins-mainly X protein and truncated preS-S protein-provided with potential transforming properties.Furthermore,OBI may indirectly favor HCC development.It has been shown that the persistence of very low viral replicative activity during OBI may induce mild liver necro-inflammation continuing for life,and substantial clinical evidence indicates that OBI canaccelerate the progression of liver disease towards cirrhosis that is considered the most important risk factor for HCC development. 展开更多
关键词 Hepatitis b virus Hepatitis b virus surface antigen Hepatitis b virus DNA Hbx protein Hepatocellular carcinoma Occult hepatitis b virus infection
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Diagnostic strategy for occult hepatitis B virus infection 被引量:16
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作者 Sara Ocana Maria Luisa Casas +1 位作者 Ingrid Buhigas Jose Luis Lledo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第12期1553-1557,共5页
In 2008,the European Association for the study of the liver(EASL) defined occult hepatitis B virus infection (OBI) as the"presence of hepatitis B virus(HBV) DNA in the liver(with detectable or undetectable HBV DN... In 2008,the European Association for the study of the liver(EASL) defined occult hepatitis B virus infection (OBI) as the"presence of hepatitis B virus(HBV) DNA in the liver(with detectable or undetectable HBV DNA in the serum) of individuals testing hepatitis B surface antigen(HBsAg) negative by currently available assays".Several aspects of occult HBV infection are still poorly understood,including the definition itself and a standardized approach for laboratory-based detection,which is the purpose of this review.The clinical significance of OBI has not yet been established;however,in terms of public health,the clinical importance arises from the risk of HBV transmission.Consequently,it is important to detect high-risk groups for occult HBV infection to prevent transmission.The main issue is,perhaps,to identify the target population for screening OBI.Viremia is very low or undetectable in occult HBV infection,even when the most sensitive methods are used,and the detection of the viral DNA reservoir in hepatocytes would provide the best evaluation of occult HBV prevalence in a defined set of patients.However,this diagnostic approach is obviously unsuitable:blood detection of occult hepatitis B requires assays of the highest sensitivity and specificity with a lower limit of detection<10 IU/mL for HBV DNA and<0.1 ng/mL for HBsAg. 展开更多
关键词 Occult hepatitis b virus infection Hepatitis b surface antigen Hepatitis b virus DNA ANTI-HbC
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A case-control study of the relationship between hepatitis B virus DNA level and risk of hepatocellular carcinoma in Qidong,China 被引量:15
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作者 Ta o-Tao Liu Ying Fang +5 位作者 Hui Xiong Tao-Yang Chen Zheng-Pin Ni ]ian-Feng Luo Nai-Qing Zhao Xi-Zhong Shen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第19期3059-3063,共5页
AIM:To investigate the role of hepatitis B virus (HBV) replication in the development of hepatocellular carcinoma (HCC), a nested case-control study was performed to study the relationship between HBV DNA level and ri... AIM:To investigate the role of hepatitis B virus (HBV) replication in the development of hepatocellular carcinoma (HCC), a nested case-control study was performed to study the relationship between HBV DNA level and risk of HCC. METHODS:One hundred and seventy cases of HCC and 276 control subjects free of HCC and cirrhosis were selected for this study. Serum HBV DNA level was measured using fluorescein quantitative polymerase chain reaction at study entry and the last visit. RESULTS:In a binary unconditional logistic regression analysis adjusted for age, cigarette smoking, alcohol consumption and family history of chronic liver diseases, the adjusted odds ratios (95% confidence intervals) of HCC in patients with increasing HBV DNA level were 2.834 (1.237-6.492), 48.403 (14.392-162.789), 42.252 (14.784-120.750), and 14.819 (6.992-31.411) for HBV DNA levels ≥ 104 to < 105; ≥ 105 to < 106; ≥ 106 to < 107; ≥ 107 copies/mL, respectively. Forty-six HCC cases were selected to compare the serums viral loads of HBV DNA at study entry with those at the last visit. The HBV DNA levels measured at the two time points did not differ significantly.CONCLUSION:The findings of this study provide strong longitudinal evidence of an increased risk of HCC associated with persistent elevation of serum HBV DNA level in the 104-107 range. 展开更多
关键词 Hepatitis b surface antigen Viral replication Asvmptomatic carriers Viral load
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Inhibition of hepatitis B virus by oxymatrine in vivo 被引量:13
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作者 Xiao Song Chen1 Guo Jun Wang1 +2 位作者 Xiong Cai1 Hong Yu Yu2 Yi Ping Hu3 1Department of Infectious Diseases, Changzheng Hospital, the Second Military Medical University, Shanghai 200003, China2Department of Pathology, 3Department of Cell Biology, Department of Basic Medicine, the Second Military Medical University, Shanghai 200433, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第1期49-52,共4页
AIM To investigate the anti-HBV effect ofoxymatrine (oxy) in vivo.METHODS HBV transgenic mice were producedby micro-injection of a 4.2kb fragmentcontaining the complete HBV genomes.Expression level of HBsAg and HBcAg ... AIM To investigate the anti-HBV effect ofoxymatrine (oxy) in vivo.METHODS HBV transgenic mice were producedby micro-injection of a 4.2kb fragmentcontaining the complete HBV genomes.Expression level of HBsAg and HBcAg in thetransgenic mice liver was determined byimmunohistochemical assay.RESULTS Four groups (6 mice in each group)were injected intraperitoneally with oxy at thedosage of 100,200, and 300 mg/kg or with salineonce a day for 30 days. Both HBsAg and HBcAgwere positive in livers of all the six mice in thecontrol group (injected with saline), and werepositive in livers of two mice in 100 mg/kg groupand 300mg/kg group. In 200mg/kg group,HBsAg and HBcAg were negative in livers of allthe six mice. Based on the results, 200 mg/kg isthe ideal dosage to explore the effect of oxy atdifferent time points. According to the oxytreatment time, mice were divided into fourgroups: 10 d, 20 d, 30 d and 60 d (4 mice in eachgroup). Each mouse underwent liver biopsy twoweeks before the treatment of oxy. Down-regulation of HBsAg and HBcAg appeared aftertreatment of oxymatrine for 10 d and 20 d, Dane-like particles disappeared after the treatment ofoxy for 20d under electron microscopy,however, the expression level of HBsAg andHBcAg returned to normal 60 d later after oxytreatment.CONCLUSION oxymatrine can reduce thecontents of HBsAg and HBcAg in transgenic miceliver, longer treatment time and larger dosagedo not yield better effects. 展开更多
关键词 ALKALOIDS Animals Antiviral Agents DNA Viral Dose-Response Relationship Drug Gene Expression Regulation Viral Hepatitis b Hepatitis b Core Antigens Hepatitis b surface Antigens Hepatitis b virus development MICE Mice Transgenic Research Support Non-U.S. Gov't Virus Replication
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Detection of anti-preS1 antibodies for recovery of hepatitis B patients by immunoassay 被引量:15
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作者 Jun Wei Guang-Di Li Yuan Wang Zu-Chuan Zhang,Institute of Biochemsitry and Cell Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China Yu-Qin Wang Zhi-Meng Lu,Department of Clinical virology,Rui-Jin Hospital,Shanghai Second Medical University 200025,Shanghai,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期276-281,共6页
AIM: To establish a convenient immunoassay method based on recombinant antigen preS1(21-119aa) to detect anti-preS1 antibodies and evaluate the clinical significance of antibodies in hepatitis B. METHODS: The expressi... AIM: To establish a convenient immunoassay method based on recombinant antigen preS1(21-119aa) to detect anti-preS1 antibodies and evaluate the clinical significance of antibodies in hepatitis B. METHODS: The expression plasmid pET-28a-preS1 was constructed, and a large quantity of preS1(21-119aa) fragment of the large HBsAg protein was obtained. The preS1 fragment purified by Ni(2+)-IDA affinity chromatography was used as coated antigen to establish the indirect ELISA based on streptavidin-biotin system for detection of the anti-preS1 antibodies in sera from HBV-infected patients. For follow-up study, serial sera were collected during the clinical course of 21 HBV-infected patients and anti-preS1 antibodies, preS1 antigen, HBV-DNA and other serological HBV markers were analyzed. RESULTS: preS1(21-119aa) fragment was highly expressed from the plasmid pET-28a-preS1 in a soluble form in E.Coli (30mg.L(-1)), and easily purified to high purity over 90% by one step of Ni(2+)-IDA-sepharose 6B affinity chromatography. The purity and antigenicity of the purified preS1(21-119aa) protein was determined by 150g.L(-1) SDS-PAGE, Western blot and a direct ELISA. Recombinant preS1(21-119aa) protein was successfully applied in the immunoassay which could sensitively detect the anti-preS1 antibodies in serum specimens of acute or chronic hepatitis B patients. Results showed that more than half of 19 acute hepatitis B patients produced anti-preS1 antibodies during recovery of the disease, however, the response was only found in a few of chronic patients. In the clinical follow-up study of 11 patients with anti-preS1 positive serological profile, HBsAg and HBV-DNA clearance occurred in 6 of 10 acute hepatitis B patients in 5-6 months, and seroconversion of HBeAg and disappearance of HBV-DNA occurred in 1 chronic patients treated with lavumidine, a antiviral agent. CONCLUSION: The high-purity preS1(21-119aa) coated antigen was successfully prepared by gene expression and affinity chromatography. Using this antigen, a conveniently de 展开更多
关键词 Amino Acid Sequence ANTIbODIES base Sequence Genetic Vectors Hepatitis b Hepatitis b surface Antigens Humans IMMUNOASSAY Molecular Sequence Data Peptide Fragments Protein Precursors Recombinant Fusion Proteins Research Support Non-U.S. Gov't Viral Envelope Proteins
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四色流式细胞术检测急性B淋巴细胞白血病残留细胞 被引量:13
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作者 刘艳荣 王卉 +5 位作者 常艳 程翼飞 付家瑜 张乐萍 刘桂兰 陈珊珊 《中华血液学杂志》 CAS CSCD 北大核心 2005年第6期327-331,共5页
目的探讨利用多参数流式细胞术检测急性B淋巴细胞白血病(BALL)残留细胞的方法和意义。方法采用四色流式细胞术,以4~6组四色抗体组合检测213例BALL患者免疫分型;以CD34、CD10、CD45、CD19为主的2种四色荧光标记抗体组合监测50例297份BAL... 目的探讨利用多参数流式细胞术检测急性B淋巴细胞白血病(BALL)残留细胞的方法和意义。方法采用四色流式细胞术,以4~6组四色抗体组合检测213例BALL患者免疫分型;以CD34、CD10、CD45、CD19为主的2种四色荧光标记抗体组合监测50例297份BALL患者骨髓标本微量残留白血病细胞,同时检测分析26份化疗后处于再生期骨髓标本中B祖细胞的免疫表型特点,并以相对定量方法比较了再生期B祖细胞与B系白血病细胞CD10、CD19和CD34表达量的差异。结果213例BALL患者中,71.8%患者存在CD45、CD34、CD19、CD10表达量的异常,只存在CD38弱阳性及髓系标志患者占8.1%。微量残留白血病细胞监测的50例患者中,12例患者存在0.06%~7.73%的白血病细胞,其中11例残留白血病细胞以CD45、CD34、CD19、CD10异常表达为主。50例患者中5例临床复发,4例在复发前7~17周微量残留病(MRD)检测阳性,且均>0.1%,1例MRD检测阴性。再生期B祖细胞依据CD45、CD34、CD19、CD10、CD22和CD20表达不同可分为3期。结论多参数流式细胞术检测MRD具有快速、敏感可定量的优势,对白血病复发有更强的预测性。 展开更多
关键词 四色流式细胞术 检测 急性b淋巴细胞白血病 残留细胞
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