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Associação entre hanseníase e infecção pelo vírus da hepatite B: estudo de caso-controle / Association between leprosy and hepatitis B virus infection: case-control studyMartelli, Celina Maria Turchi 27 November 1995 (has links)
Um estudo de caso-controle para investigar a associação entre a hanseníase e infecção pelo vírus da hepatite B (VHB) foi conduzido no período de 1992/93, na cidade de Goiânia e municípios contíguos - Estado de Goiás. Avaliou-se, também, a distribuição espacial da hanseníase neste aglomerado urbano. Inicialmente, os indivíduos com suspeita clínica de hanseníase foram submetidos a exames baciloscópicos e histopatológicos, independentemente da rotina do Programa de Controle de Hanseníase. Do total de 855 pacientes recémdiagnosticados de hanseníase, 600 eram residentes em área urbana, e foram categorizados em casos multibacilares (31,3 por cento ), paucibacilares (51,8 por cento ) e prováveis (16,8 por cento ). Foi realizada análise descritiva desta casuística, havendo nítida predominância do sexo masculino na forma multibacilar de hanseníase. A distribuição espacial dos pacientes possibilitou, através da análise exploratória das taxas de detecção, discriminar estratos de risco intra-urbano. Para o estudo de caso-controle, 552 pacientes de hanseníase de 1 O a 70 anos foram incluídos. Os controles (N =552) foram selecionados de indivíduos com ausência de sinais e sintomas sugestivos de hanseníase oriundos da demanda espontânea de ambulatórios de 7 unidades de saúde, localizadas na região de procedência dos casos. Os participantes - casos e controles - foram entrevistados para avaliar fatores de risco para hanseníase e infecção pelo vírus da hepatite B. Foram coletadas amostras de sangue para detecção de marcadores ao vírus da hepatite B pela técnica de ELISA. Comparou-se a prevalência de marcadores de exposição (anti-HBc), de imunidade (anti-HBs) e de portador (AgHBs) entre casos e controles. Foram avaliados como potenciais fatores de confusão: sexo, idade, condições sócio-econômicas, estado nutricional, cicatriz vacinal de BCG e utilização dos serviços de saúde. Casos e controles foram similares quanto às características sócio-econômicas e nutricionais indicando que o princípio de selecionar controles da mesma base populacional que os casos parece ter sido adequado. Cicatriz vacinal de BCG esteve estatisticamente associada aos diferentes tipos de hanseníase. Houve maior proporção de indivíduos hospitalizados nos útimos 5 anos entre casos que em controles indicando que o emparelhamento por local de residência não eliminou completamente as diferenças entre os grupos em relação ao uso dos serviços de saúde. Entre os participantes do estudo, 18,1 por cento dos casos e 19,6 por cento dos controles foram soropositivos ao anti-HBc. Em análise multivariada, utilizando-se o modelo de regressão logística politômica, a associação da hanseníase e anti-HBc entre casos e controles apresentou odds ratio de 0,9 (IC95 por cento O, 7-1 ,3) para a categoria de multibacilar; 1,0 (IC 95 por cento 0,7-1,3) para a de paucibacilar e 1,1 (IC95 por cento 0,8-1,5) para a de provável. Estes resultados mostraram que subgrupos de casos e os controles estiveram igualmente expostos ao vírus da hepatite B. As proporções de indivíduos imunes foram semelhantes nos grupos de casos (9,2 por cento ) e controles (10,2 por cento ). Casos multibacilares responderam à exposição viral com formação de anticorpos protetores, qualitativa e quantitativamente de maneira semelhante aos pacientes paucibacilares e grupo controle. Os resultados dos índices de persistência de infecção (PPI) indicaram não haver diferença quanto ao clearance do antígeno viral nos subgrupos de casos e controles. Os resultados obtidos nesta investigação mostraram nos subgrupos de casos e controles: (i) prevalências semelhantes dos marcadores de exposição, de imunidade e de estado de portador; (ii) capacidade similar para produção de anticorpos protetores, avaliada através dos percentuais do marcador anti-HBs e, quantitativamente, através do Índice de Elisa e (iii) baixa probabilidade de persistência da antigenemia mensurada pelo PPI. Em conclusão, não houve evidências epidemiológicas de uma associação entre hanseníase e infecção pelo vírus da hepatite B, avaliada através de estudo de caso-controle, conduzido em área de baixa endemicidade ao VHB e alta endemicidade de hanseníase. / A case-control study was conducted in Goiânia, Central Brazil, a highly endemic area for leprosy and Iow endemic region for hepatitis B virus (HBV) infection. The purpose was to investigate the association between leprosy types and hepatitis B infection. The spatial distribution of leprosy in urban area was assessed. Between 1992 and 1993, newly detected leprosy cases (N=855) were investigated and 600 cases lived in the urban area. They were classified in multibacillary (31.3 per cent ), paucibacillary (51.8 per cent ) and probable cases (16.8 per cent ) according to histopathological and baciloscopic exams, independently of the leprosy control routine. The majority of multibacillary cases was males. Detection rates of leprosy were calculated by mapping cases and several risk strata were identified by using exploratory data analysis. This methodology seems to be particularly useful for targeting control activities in urban areas. Cases were 552 leprosy patients from the urban area and adjacent counties, between the ages of 1O and 70 years who self-referred or were referred to the main outpatient clinic for treatment in the region. 552 controls were selected from among self-referred outpatients from 7 health centers geographically located in areas where the cases came from. The main criteria for eligibility for control subjects was that they must not have any signs or symptoms indicative of leprosy. Blood samples were collected for all participants to determine serological markers of HBV infection and tested by enzyme immunoabsorbent assay technique (ELISA). Cases and controls were interviewed in order to evaluate risk factors for leprosy and hepatitis B vírus (HBV) infection. Prevalence of HBV exposure (anti-HBc), immunity (anti-HBs) and carrier status (AgHBs) were compared among cases and controls. Cases and controls were also compared for age, sex, socio-economic conditions, nutritional status, BCG scars and previous hospitalization. The participants had similar socio-economic pattern and also nutrition status, suggesting that the source of control selection was adequate for controlling for the most common confounding variables. BCG vaccine appeared to provide protection against multibacillary and paucibacillary types of leprosy and percentage of hospitalization was higher among cases. Prevalence of anti-HBc was similar among leprosy cases (18.1 per cent ) compared to controls (19.6 per cent ). An analysis of association between anti-HBc infection and leprosy types in terms of odds ratio, calculated by polytomous logistic regression, showed no positive association: multibacillary (OR=0.9 CI95 per cent 0.7-1.3); paucibacillary (OR= 1.0 CI95 per cent 0.7-1.3) and probable (OR= 1.1 CI95 per cent 0.8-1.5). The main findings of the case-control study were: (i) cases and controls had similar leveis of viral exposure, immune and carrier status (íi) the persistence of antigen response (PPI) was low among cases and controls respectively; (iii) ELISA índices were similar among multibacillary, paucibacillary and control group indicating that all participants mount antibody response to viral infection. In conclusion, there was no association between multibacillary leprosy and HBV infection in this setting.
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Novel mutations in the Hepatitis B virus genome in human hepatocellular carcinomas. / CUHK electronic theses & dissertations collectionJanuary 1996 (has links)
by Zhong Sheng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (p. 186-203). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.
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Hepatitis virus reactivation in cancer patients undergoing cytotoxic chemotherapy: incidences, associated factors and management. / CUHK electronic theses & dissertations collection / Digital dissertation consortiumJanuary 2001 (has links)
by Winnie Yeo. / Thesis (M.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 213-256). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.
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Virological characteristics of hepatitis B e antigen-negative chronic hepatitis B virus infection in China.January 2007 (has links)
Zhu, Lin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 103-118). / Abstracts in English and Chinese. / Contents --- p.I / List of Abbreviations --- p.IV / List of Tables and Figures --- p.V / Chapter Chapter One: --- Introduction --- p.1 / Chapter 1.1 --- Viral Hepatitis --- p.2 / Chapter 1.2 --- Global Epidemiology of HBV --- p.3 / Chapter 1.3 --- Modes of Transmission --- p.4 / Chapter 1.4 --- Diagnostic Tests --- p.5 / Chapter 1.4.1 --- HBeAg and Anti-HBe --- p.7 / Chapter 1.4.2 --- Serum Enzymes --- p.8 / Chapter 1.4.3 --- HBV DNA Assays --- p.9 / Chapter 1.4.3.1 --- HBV DNA Assays --- p.9 / Chapter 1.4.3.2 --- Clinical Applications of DNA Assays --- p.10 / Chapter 1.4.4 --- Histology --- p.13 / Chapter 1.5 --- Natural Course of Chronic Hepatitis infection --- p.18 / Chapter 1.5.1 --- Phases of chronic hepatitis B --- p.18 / Chapter 1.5.2 --- HBeAg-negative chronic hepatitis B --- p.21 / Chapter 1.6 --- Molecular biology of HBV --- p.23 / Chapter 1.6.1 --- Overview --- p.23 / Chapter 1.6.2 --- Genomic structure and organization --- p.24 / Chapter 1.6.2.1 --- Surface ORF --- p.24 / Chapter 1.6.2.2 --- Precore/Core ORF --- p.25 / Chapter 1.6.2.3 --- Polymerase ORF --- p.25 / Chapter 1.6.2.4 --- X ORF --- p.26 / Chapter 1.7 --- Genetic Variation of HBV --- p.31 / Chapter 1.7.1 --- HBV genotypes --- p.31 / Chapter 1.7.2 --- Predominant genotypes and their subgroups in Asia --- p.33 / Chapter 1.7.3 --- HBV mutations --- p.36 / Chapter 1.7.3.1 --- Precore mutations --- p.37 / Chapter 1.7.3.2 --- Core promoter mutations --- p.38 / Chapter 1.7.3.3 --- Other Mutations associated with clinical outcome --- p.40 / Chapter Chapter Two: --- Methodology --- p.44 / Chapter 2.1 --- Aims and Hypothesis --- p.45 / Chapter 2.1.1 --- Aims --- p.46 / Chapter 2.1.2 --- Hypothesis --- p.47 / Chapter 2.2 --- Patient Recruitment --- p.48 / Chapter 2.3 --- Laboratory Assays --- p.49 / Chapter 2.3.1 --- Preparation of serum HBV DNA --- p.49 / Chapter 2.3.2 --- Quantification of serum HBV DNA --- p.51 / Chapter 2.4 --- Full-genome Amplification of HBV DNA --- p.53 / Chapter 2.5 --- Full-genome Sequencing of HBV DNA --- p.55 / Chapter 2.6 --- Assembly of HBV Full-genome Sequence --- p.58 / Chapter 2.7 --- Phylogenetic Analysis --- p.59 / Chapter 2.7.1 --- Construction of phylogenetic tree --- p.59 / Chapter 2.7.2 --- Genotype and subgenotype determination --- p.60 / Chapter 2.8 --- HBV Mutations --- p.62 / Chapter 2.9 --- Info-gain program --- p.64 / Chapter 2.10 --- Statistical Analysis --- p.65 / Chapter Chapter Three: --- Results --- p.67 / Chapter 3.1 --- Patient Information --- p.68 / Chapter 3.2 --- Phylogenetic Analysis --- p.69 / Chapter 3.3 --- HBV genotypes/subgenotypes --- p.76 / Chapter 3.4 --- “Hot-spo´tح HBV Mutants --- p.79 / Chapter 3.5 --- HBV Mutation Associated with Liver Fibrosis --- p.82 / Chapter 3.5.1 --- Mutant selection --- p.82 / Chapter 3.5.2 --- Clinical significance of novel mutants --- p.84 / Chapter Chapter Four: --- Discussion --- p.88 / Chapter 4.1 --- Full-genome Sequencing Strategy --- p.89 / Chapter 4.2 --- HBV genotypes/subgenotypes Distribution and Disease Activity --- p.90 / Chapter 4.2.1 --- HBV genotypes/subgenotypes distribution --- p.90 / Chapter 4.2.2 --- Clinical significance of genotypes/subgenotypes --- p.91 / Chapter 4.3 --- HBV Hotspot Mutants and Disease Activity --- p.93 / Chapter 4.4 --- HBV Novel Mutants --- p.96 / Chapter 4.5 --- Limitation of the Study and Future Work --- p.97 / Chapter 4.5.1 --- Limitation --- p.97 / Chapter 4.5.2 --- Future Direction --- p.98 / Chapter Chapter Five: --- Conclusions --- p.99 / References --- p.102
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Molecular characterization of the hepatitis B virus X geneMalinga, Lesibana Anthony January 2010 (has links)
Thesis ( M Med (Virological Pathology))--University of Limpopo, 2010. / Introduction: Hepatitis B virus (HBV) is a serious problem worldwide causing
various liver diseases such as chronic hepatitis and hepatocellular carcinoma (HCC).
The pathogenesis of HBV related HCC is not well established. Hepatitis B X protein
(HBx) plays an important role in the pathogenesis of HCC. HBx coded by HBV X
gene enhances several cellular pathways in hepatocytes which may lead to HCC.
The genetic variability of other HBV genomic regions plays a significant role in
diagnosis, vaccine development and drug resistance. However, the genetic
variability of HBV X gene is not well understood. In addition the dual basal core
promoter mutations found within the X gene have been implicated in the inhibition of
hepatitis B e antigen (HBeAg) expression. Studies focusing on HBV X gene are
scarce in South Africa. Consequently HBV X gene variability may reveal interesting
mutations and substitutions that are important in chronic liver diseases or HCC. This
study aimed at characterising HBV X gene at a molecular level isolated from patients
with different serological profiles.
Methods: This was an exploratory study which used 20 stored sera (-70°C)
collected from adult patients at Dr George Mukhari hospital, Pretoria. The samples
were already tested for HBsAg, anti-HBs, anti-HBc and HBeAg serological markers
(Elecsys, Roche Diagnostics, Penzburg, Germany). HBV DNA extraction was
performed from serum using High Pure Viral Nucleic Acid Assay (Roche Diagnostics,
Penzburg, Germany). Nested PCR assay was used for the amplification of 465
nucleotide HBV X gene. Sequencing of PCR positive samples was done using
spectruMedix SCE2410 genetic analysis system. Six samples selected, were cloned
into the pGEM®-T Easy vector system (Promega, Madison, USA). Three clones of
each sample were selected and their plasmids purified using Pure Yield™ Plasmid
Miniprep System (Promega, Madison, USA). The plasmid DNA was recovered using
optimised nested PCR assay and sequenced. A total of 38 sequences were
generated from the study and compared with reference strains retrieved from
GenBank. Phylogenetic analysis based on HBV X gene sequences was done using
MEGA 4 software to determine different genotype clusters.
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Results: HBV X gene was successfully detected and amplified in 20 study samples.
The sequenced HBV X gene products revealed mutations and insertions. Particularly
a six nucleotide insertion, GCATGG between nucleotides 1611 and 1618 which was
detected in five samples. In addition, the six cloned samples confirmed the six
nucleotide insertion and other mutations associated with inhibition of hepatitis B e
antigen (HBeAg) detected in the study. The substitutions within HBx were detected
in the N (1-50 amino acids) and C (51-154) terminals by comparing our sequences
with archival sequences from GenBank. Important substitutions found within the N
and C terminals were S31A, P38S, A42P, F73L, H94Y, P101S, K118T, D119N,
I127T/N, K130M and V131I. These substitutions are associated with various
biological functions and pathogenesis. Other substitutions with unknown functions
detected in the study include A2G, A3G, A4G, C6W, P42S and V116L. Further
mutations of T1753M, A1762T and G1764A associated with inhibition of HBeAg
expression were detected in most samples and only one sample had C1766T
mutation. Phylogenetic analysis resulted in A, C and D HBV genotypes. Five
samples and 11 clones clustered with genotype D, two samples and four clones
clustered with genotype C and finally 13 samples and 3 clones clustered with
genotype A.
Conclusion: HBV X gene was successfully characterised using various molecular
methods. HBx substitutions detected are involved in various pathogenic effects and
may present a risk of HCC for patients infected with HBV. Genotype D samples
displayed most mutations/substitutions and this can be regarded as an important
genotype with high risk of HCC. The detection of a six nucleotide insertion
(GCATGG) in 5 samples may emerge as a new variant of genotype D. Furthermore
triple mutations of T1753M/A1762T/G1764A within basal core promoter region were
detected mostly in HBeAg negative samples. However further analysis of HBV X
gene variability is needed.
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Hepatitis B-related liver disease burden in Vietnam and AustraliaNguyen, Van Thi Thuy, Public Health & Community Medicine, Faculty of Medicine, UNSW January 2008 (has links)
This thesis investigates the epidemiology of hepatitis B virus infection (HBV) and estimates HBV-related liver disease burden in Vietnam and Australia using a cross-sectional study design and mathematical modelling. A population-based seroprevalence survey was undertaken in rural Northern Vietnam. In a sample of 870 study participants, prevalence of anti-HBV core antibody (anti-HBc) and hepatitis B virus surface antigen (HBsAg) was 68.2% and 19.0%, respectively, and hepatitis B e antigen (HBeAg) was detected in 16.4% of the HBsAg-positive group. Factors associated with HBV infection (anti-HBc and/or HBsAg-positive) were age 60 years or older (adjusted odds ratio (AOR), 3.82; 95% CI, 1.35??10.80; P = 0.01), residence in Vu Thu district (AOR, 3.00; 95% CI, 2.16??4.17; P <0.001), hospital admission (AOR, 2.34; 95% CI, 1.33??4.13; P = 0.003) and history of acupuncture (AOR, 2.01; 95% CI, 1.29??3.13; P = 0.002). Household contact with a person with liver disease (AOR, 2.13; 95% CI, 1.29??3.52; P = 0.003), reuse of syringes (AOR, 1.81; 95% CI, 1.25??2.62; P = 0.002) and sharing of razors (AOR, 1.69; 95% CI, 1.03??2.79; P = 0.04) were independent predictors of HBsAg positivity. Alanine aminotransferase (ALT) level was elevated (>40 IU/L) in 43% of the HBsAg-positive group; the proportion of elevated ALT was higher in HBeAg-positive (65%) compared with HBeAg-negative (39%) (P = 0.02). Based on data from the seroprevalence study, other prevalence estimates and HBV natural history parameters, a mathematical model was used to estimate HBV-related liver disease burden in Vietnam. Estimated chronic HBV prevalence increased from 6.4 million cases in 1990 to around 8.4 million cases in 2005 and was projected to decrease to 8.0 million by 2025. Estimated HBV-related liver cirrhosis and hepatocellular carcinoma (HCC) incidence increased linearly from 21 900 and 9400 in 1990 to 58 650 and 25 000 in 2025. Estimated HBV-related mortality increased from 12 600 in 1990 to 40 000 in 2025. To estimate HBV-related HCC incidence among Australians born in the Asia-Pacific region (APR), a mathematical modelling was developed utilising HBV natural history parameters, HBV prevalence estimates in APR countries and immigration data. Chronic HBV cases among the APR-born population increased rapidly from the late 1970s, reaching a peak of 4182 in 1990. Chronic HBV prevalence increased to more than 53 000 in 2005. Estimates of HBV-related HCC increased linearly from one in 1960 to 140 in 2005, with a projected increase to 250 in 2025. Universal HBV vaccination programs in countries of origin had limited impact on projected HBV-related HCC to 2025. HBV-related HCC survival was analysed in a population-based linkage study in New South Wales (NSW), Australia. Between 1994 and 2002, 278 HCC cases notified to the NSW Cancer Registry were linked to chronic HBV infection notifications to the NSW Health Department. The majority of cases were male (83.5%) and overseas born (93.6%); Asian-born cases accounted for 72.1%. Median survival following HCC diagnosis was 15 months. HCC survival was poorer among older age groups (P <0.001), and among cases with regional spread (HR 3.23; 95% CI, 1.83??5.69; P <0.001) and distant metastases (HR 3.85; 95% CI, 2.44??6.08; P <0.001). Sex, region of birth, and study period (1994??1997 versus 1998??2002) were not associated with HCC survival. The results of these studies show that HBV infection remains a major public health challenge in highly endemic countries such as Vietnam. HBV-related liver disease burden in Vietnam was estimated to increase for at least two decades despite the introduction of a universal infant HBV-vaccination program. Similarly, HBV-related HCC among Australians born in the APR was estimated to continue to increase over the next two decades. Survival for HBV-related HCC even in settings such as Australia continues to be extremely poor. Strategies are required to expand HBV treatment to individuals with chronic HBV infection who are at greatest risk of progression to advanced liver disease.
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Studies on markers of hepatitis B virus replication in man / Eric James GowansGowans, E. J. (Eric James) Unknown Date (has links)
Offprints of author's four journal articles in pocket / Bibliography: leaves 131-147 / x, 148 leaves, [13] leaves of plates : ill. (1 col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1986
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Studies on the pathogenesis of Hepadnavirus infectionJilbert, Allison Rae January 1989 (has links)
Improved methods for the in situ hybridisation detection of messenger RNA ( mRNA ) in sections of liver tissue, were derived by use of an experimental system. This involved the use of tritiated-poly ( dT ) probes to detect poly ( A ) sequences attached to the 3 ' end of mRNA in sections of mouse liver that had been processed in various ways. The improved - methods were applied to the detection of hepatitis B virus ( HBV ) - and hepatitis delta virus ( HDV ) - RNA. In situ hybridisation and immunostaining techniques were then applied to studies of the pathogenesis of HBV and duck hepatitis B virus ( DHBV ) infection. In situ hybridisation studies of liver biopsy tissue from HBV - infected immunosuppressed renal transplant patients demonstrated an anatomical association between piecemeal necrosis and HBV replication at the cellular level in some patients. However, widespread replicative infection of hepatocytes also occurred in some patients in the presence of normal hepatocyte morphology and mild inflammatory changes indicating that at the cellular level virus replication was not necessarily a direct cytopathic process. These findings supported the view that hepatocyte Injury may : ( i ) result from immune - mediated damage directed against cells undergoing replicative, but not restricted infection ; ( ii ) eliminate cells undergoing replicative infection and favour clonal regeneration of cells undergoing restricted infection. Localisation of interferon - alpha ( IFN - alpha ) expression in liver tissue chronically infected with HBV and HDV, identified mononuclear cells and fibroblasts ( but not hepatocytes ) as the main producers of IFN - alpha. IFN - alpha - positive cells were associated with areas of liver tissue containing cells supporting virus replication and exhibiting the greatest degree of liver damage, suggesting that locally produced IFN - alpha may be a natural regulator of virus replication in chronic liver disease. Experimental DHBV infection of Pekin - Aylesbury ducks showed that virus inoculated either intravenously or intraperitoneally, gained access to randomly distributed hepatocytes without first replicating in other cell types in the liver. Virus was seen to disseminate to contiguous cells following anatomical boundaries by the third day post - inoculation. Markers of DHBV infection in liver and serum showed reproducible kinetics, and duck hepatocytes in this system appeared to be highly permissive as large amounts of DHBV DNA and DHBsAg were produced intracellularly without the development of ongoing cytopathology. Hepatocytes were the major cell type responsible for early significant DHBV replication, in contrast to pancreas, kidney, spleen and circulating mononuclear cells where significant levels of infection were detected only after the first week of infection and the onset of viraemia. / Thesis (Ph.D.)--Department of Microbiology and Immunology, 1989.
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Hepatitis B virus specific immune response after liver transplantation for chronic hepatitis B /Luo, Ying, January 2006 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.
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Unravelling the mystery of liver diseases in Egypt : the burden of disease /Yassin, Khaled. January 2001 (has links)
Thesis (doctoral)--Universität, Münster (Westfalen).
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