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Search Results: 1 - 10 of 115392 matches for " LIU Zhi-hui "
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A PRIMARY STUDY ON THE STRUCTURE AND DYNAMICS OF CASTANOPSIS FARGESII POPULATION ON JINYUN MOUNTAIN, SICHUAN PROVINCE
四川省缙云山栲树种群结构和动态的初步研究

Liu Zhi-hui,
刘智慧

植物生态学报 , 1990,
Abstract: Castanopsis fargesii is one of community species and a dominant species of evergreen broad-leaved forests in the middle subtropics of China. The study of its population is of great significance for studying the forest communities and ecosystems in subtropic China. In this paper, with the "time specific" method for life-table analysis, the Tree class structure and spatial patterning and their respective dynamic rules of Castanopasis fargesii population on Jinyun Mountain were analyzed. The quadrat method and the technique of censusing every individual are both used in fieldwork. The result shows that the Tree class structure replacing the age structure is suitable for studying the structure and dynamics of Castanopsis fargesii population. The results of the research on the Tree class structure and the survival curve suggest that the Castanopsis fargesii population is characterized by the increasing type. The spatial patterning of the population is of the clump type. However, spatial patterning alters with different Tree classes of the population. It is found that the seedling, sapling and small tree classes show the clump type, while the middle and large tree classes exhibit the random type. This regularity reflects the dynamic change of spatial patterning with time in the development of the population. This change is related to the quantitative dynamics of the population. The chief factors causing this change are the self-thining and the alien-thining cau sed by intraspecific interpecific struggle in the stand.
Evolution and phenotypic analysis of rtL229 polymerase mutations within the hepatitis B virus genome
Dong JI,Yan LIU,Zhi-hui XU,Le LI
Medical Journal of Chinese People's Liberation Army , 2012,
Abstract: Objective  The rtL229 mutations in the reverse-transcriptase (RT) domain of hepatitis B virus (HBV) polymerase have been reported to have the ability to enhance the replication capacity of lamivudine (LAM)-resistant strains. This study aimed to investigate the evolution and phenotypic characteristics of rtL229 mutations. Methods  The clinical characteristics of one representative patient with chronic hepatitis B who had received LAM treatment were retrospectively analyzed. HBV RT genes isolated from different serum samples were amplified by nested PCR, and clonal sequencing (>20 clones/sample) was done to analyze the evolution of rtL229F mutations. Meanwhile, the amplified HBV RT genes bearing different mutation patterns (wild-type, rtM204I, and rtL229F+rtM204I, respectively) were cloned into 1.1-fold HBV vector (pTriEx-mod-1.1) to generate replication-competent viral constructs. The recombinant constructs were transfected into HepG2 cells, which were cultured in the presence or absence of nucleos(t)ide analogs. Supernatant HBV DNA products were quantitated using real-time PCR . Results  rtL229F mutation was secondary to rtM204I mutation during LAM treatment, and it regressed to wild-type strains together with rtM204I mutation after LAM withdrawal. Phenotypic assay showed that the single rtL229F mutation had no impact on the drug-susceptibility of HBV to nucleos(t)ide analogs, but could enhance the drug resistance of LAM-resistant rtM204I strain. Conclusion  The rtL229F site mutation might be a compensatory mutation of LAM resistance, which is associated with suboptimal response to LAM treatment, and it still is susceptible to the treatment of adefovir dipivoxil, entecavir and tenofovir in vitro.
Biological characteristics and AFLP fingerprints of Phytophthora infestans strains DK98-1, DX98-2 and DX98-3
马铃薯晚疫病菌DK98-1、DX98-2和DX98-3的生物学特性及AFLP指纹分析

YANG Zhi-Hui,YANG Zhi-Hui,LIU Da-Qun,LIU Shun,
朱杰华
,杨志辉,刘大群,刘顺

微生物学报 , 2007,
Abstract: 利用黑麦培养基和V8-蔬菜汁培养基研究了马铃薯晚疫病菌Phytophthora infestans特异菌株DK98-1、DX98-2和DX98-3 的生物学特性,发现该菌株与普通菌株相比菌落生长速度慢、孢子囊产生数量少、有性杂交后卵孢子产生量大(2047~75623个/cm2);利用AFLP分子标记研究这3个菌株的DNA指纹图谱,发现用引物E+CG/M+CC扩增菌株DK98-1、DX98-2和DX98-3后,在330bp处与普通菌株相比各缺失一条谱带,用引物E+AC/M+CT扩增菌株DK98-1、DX98-2和DX98-3后,在370bp处比普通菌株增加1条谱带,说明这3个菌株与普通菌株在遗传上明显不同。同时可以利用上述2对特异性引物,鉴定在自然界的晚疫病菌群体中这类特异菌株的出现频率。
Identification and analysis of phenotypic resistance characteristics of a novel mutation rtL180M+A181C+M204V in HBV reverse-transcriptase region of a patient with chronic hepatitis B
Jia-hui LIU,Yan LIU,Zhi-hui XU,Yan WANG
Medical Journal of Chinese People's Liberation Army , 2012,
Abstract: Objective  To identify a novel mutation rtA181C in HBV reverse-transcriptase (RT) region of a chronic hepatitis B (CHB) patient receiving sequential anti-HBV nucleoside/nucleotide analogues, and to analyze its phenotypic resistance characteristics. Methods  A 43-year-old CHB patient was identified in 302 Hospital of PLA in June 2010, serum HBV DNA was extracted and the HBV RT gene was amplified by nested PCR. The direct PCR sequencing and clonal sequencing were performed, and 12 drug-resistance-associated sites were analyzed. The recombinant plasmids pTriEx-HBV1.1 containing representative variation in RT region were constructed and transfected into HepG2 cells. The cell medium was supplemented with various concentrations of lamivudine, adefovir, entecavir and tenofovir 4 hours post-transfection. Four days later, HBV DNA level in the cell supernatant was quantified by real time PCR and the viral phenotypic resistance characteristics was analyzed. Results  The patient receiving lamivudine for 36 months, adefovir for 14 months, and entecavir for 29 months consecutively, and viral rebound and biochemical breakthrough subsequently occurred. HBV DNA increased to 1.1×106IU/ml, and ALT level increased to 235U/L. rtL180M+A181V+M204V mutation was identified in HBV RT region, and clonal analysis showed that 9 of 18 clones for rtL180M+A181V+M204V, 7 of 18 for rtL180M+A181C+M204V, 1 of 18 for rtV173L+L180M+A181V, and 1 of 18 for wild type virus were obtained. The viral replication capacity showed that wild type>rtV173L+L180M+A181V>rtL180M+A181C+M204V>rtL180M+A181V+M204V. Compared to the wild type virus, rtL180M+A181V+M204V and rtV173L+L180M+A181V variants were relatively less susceptible to lamivudine and adefovir, while rtL180M+A181C+M204V variant was less susceptible to lamivudine and entecavir. Conclusions  Long-term sequential treatment with nucleoside/nucleotide analogues may lead to occurrence of multidrug resistance; production of novel substitution in form of rtA181C from rt181 may be related to long-term administration of entecavir, and it probably is a novel drug-resistant mutation site of entecavir.
A Grid Resources Allocation Mechanism Based on Futures Markets Theory
一种基于期货市场理论的网格资源分配机制

LIU Hui-Bin,DU Zhi-Hui,
刘会斌
,都志辉

计算机科学 , 2006,
Abstract: After comparing the characteristics of grid computing resource and futures, a grid resource allocation mechanism based on futures markets theory is presented. Simulation results show that futures market model can avoid price fluctuating. A new allocation algorithm based on competition is proposed. The performance of the allocation algorithm based on competition and coweb model is compared by experiments. The experimental results indicate that the algorithm based on competition is more stable with higher utilization ratio of the grid resource. A scheduling algorithm based on futures contract within a domain of grid resource is presented. The performances of the scheduling algorithm based on futures contract, first come first served model, Cluster Round robin algorithm and Marmin scheduling algorithm are compared by experiments, and the experimental results indicate that the scheduling algorithm based on futures contract algorithm can attain the shortest response time among them. Grid computing, futures markets theory and its application in power system are also discussed.
The Convergence of Grid and Web Services-WSRF and WS-Notification
网格与Web服务的融合—WSRF和WS-Notification

LIU Hui-Bin,DU Zhi-Hui,
刘会斌
,都志辉

计算机科学 , 2005,
Abstract: The WS-Notification specification and the WS-Resource Framework (WSRF) provide a scalable publish/ subscribe (pub/sub) messaging model and the ability to model stateful resources using Web services. In this paper, the relationhip between OGSI and the WSRF is introduced first. WSRF can be viewed as a straightforward re factoring of the concepts and interfaces developed in the OGSI version 1.0 specification. WSRF tries to model Stateful Re- sources with Web Services Resource approach to declaring and implementing the association between a Web service and one or more named typed state components. An approach is described for making the properties of a WS-Re- source accessible through its Web service interface and for managing a WS-Resource's lifetime. The discussion on how a pub/sub notification mechanism (WS-Notification) can be built on top of the WS Resource framework is also given. Finally,this paper also presents a summary of WSRF and WS-Notification briefly and a simple discussion on the future research.
Key problem research and implementation of snowmelt flood precaution model base system based on B/S structure
B/S结构融雪洪水预警模型库系统关键问题研究与实现

LIU Yong-qiang,LIU Zhi-hui,
刘永强
,刘志辉

计算机应用研究 , 2008,
Abstract: 通过对模型库系统的研究,建立并实现了B/S结构的基于Web的新疆融雪洪水预警模型库系统.该系统将成熟的关系型数据库系统技术与模型库理论集成在一起,结合参数元理论,并充分利用面向对象技术,从根本上解决了模型的表示、模型的管理、模型的组合运行、模型数据的共享和交换及模型的复用等关键性问题.
Relationship between single nucleotide polymorphism of chemokine CXCL10 G-210A and the chronicity and severity of HBV infection
Li-ming LIU,Zhi-hui XU,Yan LIU,Yan-wei ZHONG
Medical Journal of Chinese People's Liberation Army , 2011,
Abstract: Objective To investigate the single nucleotide polymorphism(SNP) in the promoter of chemokine CXCL10 G-201A,and explore the relationship between the SNP and the chronicity and severity of hepatitis B virus(HBV) infection.Methods Blood samples were collected from 792 patients with HBV infection,including 200 with acute hepatitis B(AHB),200 with mild/moderate chronic hepatitis B(CHB-M),192 with severe chronic hepatitis B(CHB-S) and 200 with acute liver failure of chronic hepatitis(ACLF),and 300 healthy people were enrolled as normal control(NC).DNA were extracted and subjected to PCR amplification of fragment containing C-1596 site that links with G-201 variation,followed by restriction fragment length polymerase(RFLP) analysis.Simultaneously,400 samples were randomly extracted from various groups for direct sequencing of G-201 variation.The consistency of SNP typing results of the two methods was analyzed.Results Variation rates of G-201A were 17.77% for AHB group,25.26% for CHB-M group,26.59% for CHB-S group,21.28% for ACLF group,and 13.82% for NC group.The overall P value obtained from the general χ2 test among the 5 groups was 0.0037.The correlation test(P=0.0015) demonstrated that the variation rate was related to different disease status,and the linear trend test(P=0.0029,Z=-2.9748) indicated an increasing trend of variation rate with the disease progression.Paired comparison showed that the differences in variation rate between CHB-M and NC(P=0.0024),CHB-S and NC(P=0.0007),ACLF and NC(P=0.0428),as well as CHB-S and CHB(P=0.0488) were statistically significant.Direct PCR sequencing showed 98.68% identity with the results from PCR-RFLP.Kappa test(U=58.425,P < 0.05) indicated that the consistency of the two assays met the statistical requirements.Conclusion The G-201A variation in CXCL10 promoter is related to chronicity of HBV infection,and the relations between the variation and the severity of HBV infection remains to be further clarified.
Genotypic and phenotypic characteristics of multidrug-resistant hepatitis B virus infection in Chineses hepatitis B patients
Yan LIU,Zhi-hui XU,Li-ming LIU,Le LI
Medical Journal of Chinese People's Liberation Army , 2012,
Abstract: Objective  To analyze the genotypic and phenotypic characteristics of multidrug-resistant hepatitis B virus (MDR HBV) infection in a large cohort of Chinese hepatitis B patients who had undergone long-term sequential nucleos(t)ide analogs (NAs) treatment. Methods  NAs-resistance-associated mutation patterns and frequency in HBV reverse-transcriptase (RT) region were analyzed in 11 800 patients with chronic HBV infection. The MDR HBV strains from 46 patients were further identified by PCR direct sequencing and clonal sequencing (≥20 clones/sample). In vitrophenotypic resistance assay was used to investigate the inhibitory effect of combined use of nucleoside and nucleotide analogs on replication capacity of MDR HBV strains. Influence of clinical antiviral schedules on the development and control of MDR HBV infection was further analyzed. Results  (1) HBV NAs-resistant mutations were detected in the 3658 (31.0%) of 11800 tested patients, lamivudine (LAM)-, adefovir (ADV)-, entecavir (ETV)-, and telbivudine (LdT)-resistant mutations were detected in 2592 (70.9%), 665 (18.2%), 293 (8.0%), and 62 (1.7%) patients, respectivel y. In addition, MDR mutations resistant to both nucleoside and nucleotide analogs were detected in 46 (1.3%) patients. (2) Clonal sequencing showed that 40 out of 46 MDR samples harbored mutations in the same HBV genome, and MDR mutations in the other 6 were in individual HBV genomes. Fifteen mutational patterns of MDR HBV strains were detected, including 10 both LAM-/LdT-and ADV-resistant mutations and 5 both ETV-and ADV-resistant mutations. (3) In vitrophenotypic analysis showed that combination use of ETV or LAM plus ADV efficiently inhibited the replication capacity of rtL180M+M204V+S202G+A181V MDR strain in HepG2 cells, whereas the synergistic inhibitory effect was not observed in the wild-type strain. (4) Clinical drug usage showed that MDR HBV infection mainly emerged in patients receiving long-term sequential NAs therapy. Among them, 22 with LAM switched to ADV and 10 with LAM switched to ADV, followed by switching to ETV, and they successively developed virological and/or biochemical breakthrough. Remedial therapy consisting of a combination of LAM and ADV or ETV and ADV could effectively inhibit HBV replication to undetectable level in most patients harboring MDR HBV strains. Conclusions  The MDR HBV strains isolated from Chinese patients display diversity and complexity. Phenotypic analysis and clinical observation support combined use of nucleoside and nucleotide analogs for control of MDR HBV infection. The development of MD
Toxic Effects of Triphenyltin on the Growth and the Related Enzymic Activities of Lemna minor
三苯基锡对青萍生长及酶活性的影响(Toxic Effects of Triphenyltin on the Growth and the Related Enzymic Activities of Lemna minor)

SONG Zhi-hui,LIU Ge,
宋志慧
,刘歌

生态毒理学报 , 2010,
Abstract: 以青萍(Lemna mino)为实验生物,通过研究不同浓度(0、0.04、0.08、0.12、0.16、0.20mg·L-1)的三苯基锡(TPT)对青萍生长发育及过氧化氢酶(CAT)和过氧化物酶(POD)活性的影响,初步探讨了TPT对水生浮萍植物的毒性作用,以期为及时发现并排除TPT污染提供理论和直观依据. 实验结果表明:培养4d后,TPT对青萍叶片生长量的半数抑制浓度(IC50)为0.10mg·L-1;CAT、POD活性随TPT处理浓度的升高显著升高(各暴露组与对照组均差异显著,p<0.05). 结果显示,TPT对青萍具有明显的毒性作用,CAT和POD活性的变化可作为反映TPT污染胁迫的敏感指标.
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