1.The characteristic of vernier acuity on age-related macular degeneration patients
Quan LIU ; Shaozhen LI ; George WOO
Chinese Journal of Ocular Fundus Diseases 2000;0(04):-
Objective To investigate the clinical characteristic of vernier acuity in age-related macular degeneration (AMD) patients. Methods The vernier acuity test soft wear system was developed to detect the 23 cases (39 eyes) of AMD patients. Tweenty-one eyes were atrophic type and 17 eyes were exudative type. Two fixed targets and a movable target are shown on the computer screen. The examinee was asked to adjust the position of the central target and the relationship between it and align them by using a track ball. The computer automatically recorded the deviations of distances between the movable target and the specific one, and then computed and analysed the results of average threshold and variance. Results Both the atrophic and exudative AMD had higher vernier acuity threshold and its variance than normal subjects, and the differences were significant (P
2.Overview of Ebola virus vaccine.
Limin YANG ; Jing LI ; George Fu GAO ; Wenjun LIU
Chinese Journal of Biotechnology 2015;31(1):1-23
Ebola virus (EBOV) causes hemorrhagic fever, resulting in mortality rates as high as 90% among infected humans and non-human primates (NHPs). The 2014 Ebola epidemic in West Africa is the severest in history, leading to WHO taking all control measures to stop any possibility of cross-border outbreaks. Because no licensed vaccines or effective therapeutics against EBOV are available, the current outbreak management has been limited to palliative care and barrier methods to prevent transmission. Several promising experimental EBOV vaccines have demonstrated protection in NHPs against lethal EBOV challenge, and some progresses have been made through clinical trials of EBOV vaccine candidates. It is believed there will be some licensed vaccine available in the near future to control EBOV outbreaks. In this review we provide some insights for further development of EBOV vaccines.
Animals
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Ebola Vaccines
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Ebolavirus
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Hemorrhagic Fever, Ebola
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prevention & control
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Humans
3.Right atrial isomerism: preponderance in Asian fetuses. Using the stomach-distance ratio as a possible diagnostic tool for prediction of right atrial isomerism.
Ying Liu YAN ; Kenny B L TAN ; George S H YEO
Annals of the Academy of Medicine, Singapore 2008;37(11):906-912
INTRODUCTIONTo present the characteristics and spectrum of associated anomalies in right- and left-sided isomerism in our local population and to assess the possibility of using stomach-distance ratio (SDR) of less than 0.34 as a diagnostic tool to predict right atrial isomerism.
MATERIALS AND METHODSThis was a retrospective study of fetuses in our department over a period of 8 years with postnatally confirmed prenatal diagnosis of atrial isomerism.
RESULTSIn 22 cases, atrial isomerism was confirmed by post-mortem or postnatal echocardiography. Eighteen (81.8%) fetuses had right isomerism. Their main abnormal ultrasound findings were pulmonary stenosis or atresia (n = 9), atrioventricular septal defect (n = 10), right-sided stomach (n = 9), transposition of great arteries (n = 6), dextrocardia (n = 8), single ventricle (n = 4), juxtaposition of inferior vena cava and descending aorta (n = 5), ventricular septal defect (n = 2), interrupted inferior vena cava with azygous drainage (n = 2) and double outlet right ventricle (n = 3). Four (18.2%) fetuses had left isomerism. Their abnormal ultrasound findings were dextrocardia (n = 3), right-sided stomach (n = 3), atrioventricular septal defect (n = 2), double outlet ventricle (n = 2), ventricular septal defect (n = 1), pulmonary stenosis (n = 2) and interrupted inferior vena cava with azygous drainage (n = 1). 66.7% (12/18) of cases with right isomerism had SDR of less than 0.34 compared to 0% (0/4) of the cases with left isomerism (P = 0.02).
CONCLUSIONOur study suggests an Asian predilection towards right isomerism compared to Western populations. We postulate that there may be racial differences in the expression of these 2 forms of isomerism. The ultrasound findings of complex heart disease and abnormal arrangement of great vessels in abdominal cavity, though important, are varied and non-specific evidence for either form of fetal atrial isomerism. There is a possibility of using the SDR <0.34 (representing stomach proximity to the fetal spine) as a possible diagnostic tool to predict right-sided atrial isomerism.
Asia ; epidemiology ; Diagnosis, Differential ; Echocardiography ; Female ; Follow-Up Studies ; Gestational Age ; Heart Atria ; abnormalities ; Heart Defects, Congenital ; diagnostic imaging ; epidemiology ; Humans ; Pregnancy ; Prenatal Diagnosis ; methods ; Prevalence ; Retrospective Studies ; Stomach ; anatomy & histology ; Time Factors
4.Origin and molecular characterization of the human-infecting H6N1 influenza virus in Taiwan.
Weifeng SHI ; Yi SHI ; Ying WU ; Di LIU ; George F GAO
Protein & Cell 2013;4(11):846-853
In June 2013, the first human H6N1 influenza virus infection was confirmed in Taiwan. However, the origin and molecular characterization of this virus, A/Taiwan/2/2013 (H6N1), have not been well studied thus far. In the present report, we performed phylogenetic and coalescent analyses of this virus and compared its molecular profile/characteristics with other closely related strains. Molecular characterization of H6N1 revealed that it is a typical avian influenza virus of low pathogenicity, which might not replicate and propagate well in the upper airway in mammals. Phylogenetic analysis revealed that the virus clusters with A/chicken/Taiwan/A2837/2013 (H6N1) in seven genes, except PB1. For the PB1 gene, A/Taiwan/2/2013 was clustered with a different H6N1 lineage from A/chicken/Taiwan/ A2837/2013. Although a previous study demonstrated that the PB2, PA, and M genes of A/Taiwan/2/2013 might be derived from the H5N2 viruses, coalescent analyses revealed that these H5N2 viruses were derived from more recent strains than that of the ancestor of A/Taiwan/2/2013. Therefore, we propose that A/Taiwan/2/2013 is a reassortant from different H6N1 lineages circulating in chickens in Taiwan. Furthermore, compared to avian isolates, a single P186L (H3 numbering) substitution in the hemagglutinin H6 of the human isolate might increase the mammalian receptor binding and, hence, this strain's pathogenicity in humans. Overall, human infection with this virus seems an accidental event and is unlikely to cause an influenza pandemic. However, its co-circulation and potential reassortment with other influenza subtypes are still worthy of attention.
Amino Acid Sequence
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Amino Acid Substitution
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Animals
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Hemagglutinin Glycoproteins, Influenza Virus
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chemistry
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genetics
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Humans
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Influenza A Virus, H5N2 Subtype
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genetics
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physiology
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Influenza A virus
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genetics
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isolation & purification
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physiology
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Influenza, Human
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epidemiology
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virology
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Laboratories
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Models, Molecular
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Molecular Sequence Data
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Phylogeny
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Poultry
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virology
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Protein Conformation
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Taiwan
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epidemiology
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Viral Proteins
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genetics
5.Evaluating a simplified method for identifying high-risk individuals for cardiovascular diseases in the resource-constrained rural areas of China.
Xian LI ; Tingming LIU ; Jianxin ZHANG ; Lijing YAN ; Jixin SUN ; Zhixin HAO ; Cong LI ; Yangfeng WU ;
Chinese Journal of Epidemiology 2014;35(9):981-984
OBJECTIVEThis research project aimed to evaluate whether a simplified method for identifying high-risk individuals for cardiovascular diseases proposed by the China Rural Health Initiative (CRHI) was feasible in the rural areas in China.
METHODS2 036 adults, aged 20 years or older were stratified-randomly sampled from 12 villages in Luquan county and Anguo county (Hebei province) respectively, to receive physical examination and filling in administered questionnaires. "Gold Standard" was used on high risk in Chinese Guidelines on Prevention and Treatment of Dyslipidemia in Adults to evaluate the CRHI standards:people with a history of coronary heart disease or stroke, or elderly as men ≥50 years or women ≥60 years with diabetes, or elderly with systolic blood pressure ≥160 mmHg. Sensitivity, specificity, positive and negative predictive values related to the identification of high-risk individuals for cardiovascular diseases were assessed.
RESULTSThe concordance rate between the CRHI standard and the gold standard was 92.9% , with sensitivity as 77.2%, specificity as 98.5%, Youden's Index as 0.76, positive predictive value as 94.7% and negative predictive value as 92.5%. Under CRHI standard, 21.3% of the adults were identified as high risk. The rate was increasing with age (P < 0.001), reaching 44% among those who were over 60 years old.
CONCLUSIONThe CRHI standard seemed simple and easy and was suitable for identifying high-risk individuals for cardiovascular diseases in the resource-constrained rural areas.
6.Effects of Diabetic Case Management on Knowledge, Self-Management Abilities, Health Behaviors, and Health Service Utilization for Diabetes in Korea.
Soon Ae SHIN ; Hyeongsu KIM ; Kunsei LEE ; Vivian LIN ; George LIU ; Eunyoung SHIN
Yonsei Medical Journal 2015;56(1):244-252
PURPOSE: This study aimed to evaluate the effects of a case management program for diabetics, using a pre-post comparison design. MATERIALS AND METHODS: The study population comprised 6007 diabetics who received case management intervention in 2006 and were sampled nationwide in Korea. Before and after the intervention, the study population answered questions regarding their knowledge of diabetes, self-management ability, and health behaviors. Body mass index (BMI) was also calculated. Healthcare service utilization for diabetes was extracted from health insurance claim data from 2005 to 2007. RESULTS: The case management program significantly improved the study population's knowledge of diabetes and ability to self-manage nutrition, blood glucose monitoring, foot and oral care, and medications. This program also significantly changed the study population's health behaviors regarding smoking, alcohol drinking, and exercise, and BMI was positively affected. In the over-serviced subgroup, there was a significant decrease in the number of consultations (mean=7.0; SD=19.5) after intervention. Conversely, in the under-serviced subgroup, there was a significant increase in the number of consultations (mean=3.2; SD=7.9) and the days of prescribed medication (mean=66.4; SD=120.3) after intervention. CONCLUSION: This study showed that the case management program led the study population to improve their knowledge, self-management ability, health behaviors, and utilization of health care. It is necessary in future studies to evaluate the appropriateness of healthcare usage and clinical outcome by using a control group to determine the direct effectiveness of this case management program.
Adult
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Aged
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Body Mass Index
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*Case Management
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Diabetes Mellitus/*therapy
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Female
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*Health Behavior
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*Health Knowledge, Attitudes, Practice
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Health Services/*utilization
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Humans
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Male
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Middle Aged
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Republic of Korea
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*Self Care
7.Expression and crystallographic studies of a fungal immunomodulatory protein LZ-8 from a medicinal fungus Ganoderma lucidum.
Min AN ; George Fu GAO ; Jianxun QI ; Feng LI ; Xingzhong LIU
Chinese Journal of Biotechnology 2010;26(11):1563-1568
LZ-8 protein, isolated from a well known Chinese traditional medicinal fungus Ganoderma lucidum, is the first member of fungal immunomodulatory protein, members of which have been isolated from a variety of medicinal and edible mushrooms in the last two decades. The protein plays a multifunctional and important role in modulating immune system. In this report, in order to get LZ-8 protein crystals, the LZ-8 gene was expressed and purified by affinity chromatography, gel filtration chromatography and anion exchange chromatography subsequently. The protein was then crystallized using the hanging-drop vapour-diffusion method. The LZ-8 crystals were obtained and the phase information was calculated by X-ray diffraction. The resolution of LZ-8 crystals is 3.2A. This study will provide an insight into the structure of fungal immunomodulatory proteins.
Animals
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Crystallography
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Fungal Proteins
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biosynthesis
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genetics
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immunology
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Ganoderma
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genetics
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metabolism
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Genetic Vectors
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genetics
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Immunologic Factors
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biosynthesis
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genetics
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Mice
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Recombinant Proteins
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biosynthesis
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genetics
;
immunology
8.Two conformations of pHLA-A*2402: a supplement to Wolynes' theory.
Chuansheng LIU ; Yi SHI ; George F GAO
Chinese Journal of Biotechnology 2012;28(11):1370-1377
Wolynes argued that the track of a protein's folding was directed by the tendency of lowering its energy, and thus when a local minimum of its energy was reached, a relatively stable conformation was formed. However not all of the local minimums will lead the protein to a biologically useful conformation, for those otherwise are called energy traps. Wolynes energy landscape theory and natural selection have well explained the high efficiency of protein folding in vivo, instead of being stuck in energy traps. As to whether a protein can assume different conformations with the same bioactivity, there is no clear answer yet. In this paper, two conformational states of a pHLA-A*2402 are discovered after refolding, and by studying their interactions with TCR and CD8alphaalpha, two conformations of pHLA-A*2402 are confirmed of having escaped from natural selection.
CD8 Antigens
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chemistry
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Energy Metabolism
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HLA-A24 Antigen
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chemistry
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Humans
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Protein Conformation
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Protein Folding
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Receptors, Antigen, T-Cell
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chemistry
9.Electrocardiographic features in SCN5A mutation‑positive patients with Brugada and early repolarization syndromes: a systematic review and meta‑analysis
Danny RADFORD ; Oscar Hou In CHOU ; George BAZOUKIS ; Konstantinos LETSAS ; Tong LIU ; Gary TSE ; Sharen LEE
International Journal of Arrhythmia 2022;23(3):16-
Background:
Early repolarization syndrome (ERS) and Brugada syndrome (BrS) are both J-wave syndromes. Both can involve mutations in the SCN5A gene but may exhibit distinct electrocardiographic (ECG) differences. The aim of this systematic review and meta-analysis is to investigate possible differences in ECG markers between SCN5A-positive patients with ERS and BrS.
Methods:
PubMed and Embase were searched from their inception to 20 October 2021 for human studies containing the search terms “SCN5A” and “variant” and “early repolarization” or “Brugada”, with no language restrictions.Continuous variables were expressed as mean±standard deviation. PR interval, QRS duration, QTc and heart rate from the included studies were pooled to calculate a mean for each variable amongst BrS and ERS patients. A two-tailed Student’s t test was then performed to for comparisons.
Results:
A total of 328 studies were identified. After full-text screening, 12 studies met our inclusion criteria and were included in this present study. One hundred and four ERS patients (mean age 30.86±14.45) and 2000 BrS patients (mean age 36.17±11.39) were studied. Our meta-analysis found that ERS patients had shorter QRS duration (90.40±9.97 vs. 114.79±20.10, P = 0.0001) and shorter corrected QT intervals (QTc) with borderline significance (393.63±40.04 vs. 416.82±37.43, P = 0.052). By contrast, no significant differences in baseline heart rate (65.15±18.78 vs. 76.06±18.78, P = 0.068) or PR intervals (197.40±34.69 vs. 191.88±35.08, P = 0.621) were observed between ERS and BrS patients.
Conclusion
BrS patients with positive SCN5A mutations exhibited prolonged QRS, indicating conduction abnormalities, whereas ERS patients with positive SCN5A mutations showed normal QRS. By contrast, whilst QTc intervals were longer in BrS than in ERS SCN5A positive patients, they were within normal limits. Further studies are needed to examine the implications of these findings for arrhythmic risk stratification.
10.A new unconventional HLA-A2-restricted epitope from HBV core protein elicits antiviral cytotoxic T lymphocytes.
Lu SUN ; Yu ZHANG ; Bao ZHAO ; Mengmeng DENG ; Jun LIU ; Xin LI ; Junwei HOU ; Mingming GUI ; Shuijun ZHANG ; Xiaodong LI ; George F GAO ; Songdong MENG
Protein & Cell 2014;5(4):317-327
Cytotoxic T cells (CTLs) play a key role in the control of Hepatitis B virus (HBV) infection and viral clearance. However, most of identified CTL epitopes are derived from HBV of genotypes A and D, and few have been defined in virus of genotypes B and C which are more prevalent in Asia. As HBV core protein (HBc) is the most conservative and immunogenic component, in this study we used an overlapping 9-mer peptide pool covering HBc to screen and identify specific CTL epitopes. An unconventional HLA-A2-restricted epitope HBc141-149 was discovered and structurally characterized by crystallization analysis. The immunogenicity and anti-HBV activity were further determined in HBV and HLA-A2 transgenic mice. Finally, we show that mutations in HBc141-149 epitope are associated with viral parameters and disease progression in HBV infected patients. Our data therefore provide insights into the structure characteristics of this unconventional epitope binding to MHC-I molecules, as well as epitope specific CTL activity that orchestrate T cell response and immune evasion in HBV infected patients.
Adult
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Amino Acid Sequence
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Animals
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Binding Sites
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Epitopes
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chemistry
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immunology
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metabolism
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Female
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Genotype
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HEK293 Cells
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HLA-A2 Antigen
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metabolism
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Hepatitis B Core Antigens
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chemistry
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immunology
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metabolism
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Hepatitis B virus
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genetics
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metabolism
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Humans
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Hydrogen Bonding
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Male
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Mice
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Mice, Inbred BALB C
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Mice, Transgenic
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Middle Aged
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Molecular Dynamics Simulation
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Mutation
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Protein Binding
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Protein Structure, Tertiary
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T-Lymphocytes, Cytotoxic
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immunology
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metabolism