Faculty Summaries
William S Mason, PhD
William S Mason, PhD
Professor Emeritus
William.Mason@fccc.edu
Office Phone: 215-728-2462
Office: R205

2000 - present

  • Seeger C, Zoulim F, Mason WS. Hepadnaviruses. In: Fields Virology (Knipe D, Howley P, eds), 6th Edition, Chapter 69, pp. 2185-2221. Lippincott, Williams, and Wilkins, 2013.
  • Seeger C, Mason WS. Sodium-dependent taurocholic cotransporting polypeptide: a candidate receptor for human hepatitis B virus. Gut. 2013:62:1093-95. PubMed
  • Cai D, Mills C, Yu W, Yan R, Aldrich CE, Saputelli JR, Mason WS, Xu X, Guo JT, Block TM, Cuconati A, Guo H. Identification of the disubstituted sulfonamide compounds as specific inhibitors of hepatitis B virus covalently closed circular DNA formation. Antimicrob Agents Chemother. 2012;56:4277-78. PubMed
  • Zoulim F, Mason WS. Reasons to consider earlier treatment of chronic HBV infections. Gut. 2012;61:333-6. PubMed
  • Mason WS, Low HC, Xu C, Aldrich CE, Scougall CA, Grosse A, Clouston A, Chavez D, Litwin S, Peri S, Jilbert AR, Lanford RE. Detection of clonally expanded hepatocytes in chimpanzees with chronic hepatitis B virus infection. J Virol. 2009 Sep;83(17):8396-408.PubMed
  • Reaiche GY, Le Mire MF, Mason WS, and Jilbert AJ. The persistence in the liver of residual duck hepatitis B virus covalently closed circular DNA is not dependent upon new viral DNA synthesis. Virology. 2010 Oct 25;406(2):286-92. Epub 2010 Aug 12. PubMed
  • Mason WS, Liu C, Aldrich CE, Litwin S, and Yeh MM. Clonal expansion of normal appearing hepatocytes during chronic HBV infection. J Virol. 2010;84:8308-15. PubMed
  • Seeger C, Lai MMC, and Mason WS. Molecular Biology of Hepatitis Viruses. In "The liver, biology and pathobiology", 5th edition. Lipincott, Williams & Wilkins, NY.
  • Mason WS, Low HC, Xu C, Aldrich CE, Scougall CA, Grosse A, Clouston A, Chavez D, Litwin S, Peri S, Jilbert AR, Lanford RE. Detection of clonally expanded hepatocytes in chimpanzees with chronic hepatitis B virus infection. J Virol. 2009;83:8396-408. PubMed
  • Mason WS, Xu C, Low HC, Saputelli J, Aldrich CE, Scougall C, Grosse A, Colonno R, Litwin S, Jilbert AR. The amount of hepatocyte turnover that occurred during resolution of transient hepadnavirus infections was lower when virus replication was inhibited with entecavir. J Virol. 2009 Feb;83(4):1778-89. PubMed
  • Mason WS, Litwin S, Xu C, Jilbert AR. Hepatocyte turnover in transient and chronic hepadnavirus infections. J Viral Hepat. 2007 Nov;14 Suppl 1:22-8. Review. PubMed
  • Chang J, Nicolas E, Marks D, Sander C, Lerro A, Buendia MA, Xu C, Mason WS, Moloshok T, Bort R, Zaret KS, Taylor JM. miR-122, a mammalian liver-specific microRNA, is processed from hcr mRNA and may downregulate the high affinity cationic amino acid transporter CAT-1. RNA Biol. 2004 Jul;1(2):106-13. Epub 2004 Jul 1. PubMed
  • Xu C, Yamamoto T, Zhou T, Aldrich CE, Frank K, Cullen JM, Jilbert AR, Mason WS. The liver of woodchucks chronically infected with the woodchuck hepatitis virus contains foci of virus core antigen-negative hepatocytes with both altered and normal morphology. Virology. 2007 Mar 15;359(2):283-94. Epub 2006 Oct 31. PubMed
  • Guo H, Aldrich CE, Saputelli J, Xu C, Mason WS. The insertion domain of the duck hepatitis B virus core protein plays a role in nucleocapsid assembly. Virology. 2006 Sep 30;353(2):443-50. Epub 2006 Jul 11. PubMed
  • Litwin S, Toll E, Jilbert AR, Mason WS. The competing roles of virus replication and hepatocyte death rates in the emergence of drug-resistant mutants: theoretical considerations. J Clin Virol. 2005 Dec;34 Suppl 1:S96-S107. PubMed
  • Locarnini S, Mason WS. Cellular and virological mechanisms of HBV drug resistance. J Hepatol. 2006 Feb;44(2):422-31. Epub 2005 Dec 7. Review. PubMed
  • Guo H, Mason WS, Aldrich CE, Saputelli JR, Miller DS, Jilbert AR, Newbold JE. Identification and characterization of avihepadnaviruses isolated from exotic anseriformes maintained in captivity. J Virol. 2005 Mar;79(5):2729-42. PubMed
  • Mason WS, Jilbert AR, Summers J. Clonal expansion of hepatocytes during chronic woodchuck hepatitis virus infection. Proc Natl Acad Sci U S A. 2005 Jan 25;102(4):1139-44. Epub 2005 Jan 18. PubMed
  • Zhu Y, Cullen JM, Aldrich CE, Saputelli J, Miller D, Seeger C, Mason WS, Jilbert AR. Adenovirus-based gene therapy during clevudine treatment of woodchucks chronically infected with woodchuck hepatitis virus. Virology. 2004 Sep 15;327(1):26-40. PubMed
  • Summers J, Mason WS. Residual integrated viral DNA after hepadnavirus clearance by nucleoside analog therapy. Proc Natl Acad Sci U S A. 2004 Jan 13;101(2):638-40. Epub 2003 Dec 29. PubMed
  • Summers J, Jilbert AR, Yang W, Aldrich CE, Saputelli J, Litwin S, Toll E, Mason WS. Hepatocyte turnover during resolution of a transient hepadnaviral infection. Proc Natl Acad Sci U S A. 2003 Sep 30;100(20):11652-9. Epub 2003 Sep 19. PubMed
  • Yamamoto T, Litwin S, Zhou T, Zhu Y, Condreay L, Furman P, Mason WS. Mutations of the woodchuck hepatitis virus polymerase gene that confer resistance to lamivudine and 2'-fluoro-5-methyl-beta-L-arabinofuranosyluracil. J Virol. 2002 Feb;76(3):1213-23. PubMed
  • Barrasa MI, Guo JT, Saputelli J, Mason WS, Seeger C. Does a cdc2 kinase-like recognition motif on the core protein of hepadnaviruses regulate assembly and disintegration of capsids? J Virol. 2001 Feb;75(4):2024-8. PubMed
  • Zhu Y, Yamamoto T, Cullen J, Saputelli J, Aldrich CE, Miller DS, Litwin S, Furman PA, Jilbert AR, Mason WS. Kinetics of hepadnavirus loss from the liver during inhibition of viral DNA synthesis. J Virol. 2001 Jan;75(1):311-22. PubMed
  • Zhou T, Guo JT, Nunes FA, Molnar-Kimber KL, Wilson JM, Aldrich CE, Saputelli J, Litwin S, Condreay LD, Seeger C, Mason WS. Combination therapy with lamivudine and adenovirus causes transient suppression of chronic woodchuck hepatitis virus infections. J Virol. 2000 Dec;74(24):11754-63. PubMed
  • Seeger C, Mason WS. Hepatitis B virus biology. Microbiol Mol Biol Rev. 2000 Mar;64(1):51-68. Review. PubMed
  • Guo JT, Zhou H, Liu C, Aldrich C, Saputelli J, Whitaker T, Barrasa MI, Mason WS, Seeger C. Apoptosis and regeneration of hepatocytes during recovery from transient hepadnavirus infections. J Virol. 2000 Feb;74(3):1495-505. PubMed
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1990 - 1999

  • Zhou T, Saputelli J, Aldrich CE, Deslauriers M, Condreay LD, Mason WS. Emergence of drug-resistant populations of woodchuck hepatitis virus in woodchucks treated with the antiviral nucleoside lamivudine. Antimicrob Agents Chemother. 1999 Aug;43(8):1947-54. PubMed
  • Smith RB, Carmichael JB, Gregory JA, Deckert GH, Diacon GE Jr, Evans HL Jr, Fieker DH, Graves RL, Mason WS 3rd. The state of the state's health. A report from the Oklahoma State Board of Health. J Okla State Med Assoc. 1998 Sep;91(6):362-4. PubMed
  • Pugh JC, Guo JT, Aldrich C, Rall G, Kajino K, Tennant B, England JM, Mason WS. Aberrant expression of a cytokeratin in a subset of hepatocytes during chronic WHV infection. Virology. 1998 Sep 15;249(1):68-79. PubMed
  • Evans AA, O'Connell AP, Pugh JC, Mason WS, Shen FM, Chen GC, Lin WY, Dia A, M'Boup S, Dramé B, London WT. Geographic variation in viral load among hepatitis B carriers with differing risks of hepatocellular carcinoma. Cancer Epidemiol Biomarkers Prev. 1998 Jul;7(7):559-65. PubMed
  • Mason WS, Cullen J, Moraleda G, Saputelli J, Aldrich CE, Miller DS, Tennant B, Frick L, Averett D, Condreay LD, Jilbert AR. Lamivudine therapy of WHV-infected woodchucks. Virology. 1998 May 25;245(1):18-32. PubMed
  • Bennett LL Jr, Allan PW, Arnett G, Shealy YF, Shewach DS, Mason WS, Fourel I, Parker WB. Metabolism in human cells of the D and L enantiomers of the carbocyclic analog of 2'-deoxyguanosine: substrate activity with deoxycytidine kinase, mitochondrial deoxyguanosine kinase, and 5'-nucleotidase. Antimicrob Agents Chemother. 1998 May;42(5):1045-51. PubMed
  • Guo JT, Liu C, Mason WS, Pugh JC. Cloning and expression of a cDNA encoding the large subunit of duck replication factor C. Biochim Biophys Acta. 1998 Feb 11;1395(3):293-300. PubMed
  • Moraleda G, Saputelli J, Aldrich CE, Averett D, Condreay L, Mason WS. Lack of effect of antiviral therapy in nondividing hepatocyte cultures on the closed circular DNA of woodchuck hepatitis virus. J Virol. 1997 Dec;71(12):9392-9. PubMed
  • Di Q, Summers J, Burch JB, Mason WS. Major differences between WHV and HBV in the regulation of transcription. Virology. 1997 Mar 3;229(1):25-35. PubMed
  • Guo JT, Aldrich CE, Mason WS, Pugh JC. Characterization of serum amyloid A protein mRNA expression and secondary amyloidosis in the domestic duck. Proc Natl Acad Sci U S A. 1996 Dec 10;93(25):14548-53. PubMed
  • Yang W, Mason WS, Summers J. Covalently closed circular viral DNA formed from two types of linear DNA in woodchuck hepatitis virus-infected liver. J Virol. 1996 Jul;70(7):4567-75. PubMed
  • Pugh JC, Di Q, Mason WS, Simmons H. Susceptibility to duck hepatitis B virus infection is associated with the presence of cell surface receptor sites that efficiently bind viral particles. J Virol. 1995 Aug;69(8):4814-22. PubMed
  • Fourel I, Cullen JM, Saputelli J, Aldrich CE, Schaffer P, Averett DR, Pugh J, Mason WS. Evidence that hepatocyte turnover is required for rapid clearance of duck hepatitis B virus during antiviral therapy of chronically infected ducks. J Virol. 1994 Dec;68(12):8321-30. PubMed
  • Kajino K, Jilbert AR, Saputelli J, Aldrich CE, Cullen J, Mason WS. Woodchuck hepatitis virus infections: very rapid recovery after a prolonged viremia and infection of virtually every hepatocyte. J Virol. 1994 Sep;68(9):5792-803. PubMed
  • Liu C, Mason WS, Burch JB. Identification of factor-binding sites in the duck hepatitis B virus enhancer and in vivo effects of enhancer mutations. J Virol. 1994 Apr;68(4):2286-96. PubMed
  • Mason WS, Cullen J, Saputelli J, Wu TT, Liu C, London WT, Lustbader E, Schaffer P, O'Connell AP, Fourel I, et al. Characterization of the antiviral effects of 2' carbodeoxyguanosine in ducks chronically infected with duck hepatitis B virus. Hepatology. 1994 Feb;19(2):398-411. PubMed
  • Fourel I, Saputelli J, Schaffer P, Mason WS. The carbocyclic analog of 2'-deoxyguanosine induces a prolonged inhibition of duck hepatitis B virus DNA synthesis in primary hepatocyte cultures and in the liver. J Virol. 1994 Feb;68(2):1059-65. PubMed
  • Moraleda G, Wu TT, Jilbert AR, Aldrich CE, Condreay LD, Larsen SH, Tang JC, Colacino JM, Mason WS. Inhibition of duck hepatitis B virus replication by hypericin. Antiviral Res. 1993 Mar;20(3):235-47. PubMed
  • Mason WS. The problem of antiviral therapy for chronic hepadnavirus infections. J Hepatol. 1993;17 Suppl 3:S137-42. Review. PubMed
  • Condreay LD, Wu TT, Aldrich CE, Delaney MA, Summers J, Seeger C, Mason WS. Replication of DHBV genomes with mutations at the sites of initiation of minus- and plus-strand DNA synthesis. Virology. 1992 May;188(1):208-16. PubMed
  • Jilbert AR, Wu TT, England JM, Hall PM, Carp NZ, O'Connell AP, Mason WS. Rapid resolution of duck hepatitis B virus infections occurs after massive hepatocellular involvement. J Virol. 1992 Mar;66(3):1377-88. PubMed
  • Mason WS, Taylor JM. Liver transplantation: a model for the transmission of hepatitis delta virus. Gastroenterology. 1991 Dec;101(6):1741-3. PubMed
  • Carp NZ, Saputelli J, Halbherr TC, Mason WS, Jilbert AR. A technique for liver biopsy performed in Pekin ducks using anesthesia with Telazol. Lab Anim Sci. 1991 Oct;41(5):474-5. PubMed
  • Halpern MS, England JM, Coates L, Stoltzfus CM, Mason WS. Regression of v-src DNA-induced sarcomas is under host genetic control. Virology. 1991 Feb;180(2):857-60. PubMed
  • Mason WS, Summers J, Liu C, Condreay LC, Wu TT. Chronic hepadnavirus infections. Prog Clin Biol Res. 1991;364:235-42. Review. PubMed
  • Seeger C, Summers J, Mason WS. Viral DNA synthesis. Curr Top Microbiol Immunol. 1991;168:41-60. Review. PubMed
  • Condreay LD, Aldrich CE, Coates L, Mason WS, Wu TT. Efficient duck hepatitis B virus production by an avian liver tumor cell line. J Virol. 1990 Jul;64(7):3249-58. PubMed
  • Wu TT, Coates L, Aldrich CE, Summers J, Mason WS. In hepatocytes infected with duck hepatitis B virus, the template for viral RNA synthesis is amplified by an intracellular pathway. Virology. 1990 Mar;175(1):255-61. PubMed
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1980 - 1989

  • Aldrich CE, Coates L, Wu TT, Newbold J, Tennant BC, Summers J, Seeger C, Mason WS. In vitro infection of woodchuck hepatocytes with woodchuck hepatitis virus and ground squirrel hepatitis virus. Virology. 1989 Sep;172(1):247-52. PubMed
  • Mason WS, Taylor JM. Experimental systems for the study of hepadnavirus and hepatitis delta virus infections. Hepatology. 1989 Apr;9(4):635-45. Review. PubMed
  • Petcu DJ, Aldrich CE, Coates L, Taylor JM, Mason WS. Suramin inhibits in vitro infection by duck hepatitis B virus, Rous sarcoma virus, and hepatitis delta virus. Virology. 1988 Dec;167(2):385-92. PubMed
  • Lien JM, Petcu DJ, Aldrich CE, Mason WS. Initiation and termination of duck hepatitis B virus DNA synthesis during virus maturation. J Virol. 1987 Dec;61(12):3832-40. PubMed
  • Halpern MS, Mason WS, Coates L, O'Connell AP, England JM. Humoral immune responsiveness in duck hepatitis B virus-infected ducks. J Virol. 1987 Mar;61(3):916-20. PubMed
  • Mason WS, Taylor JM, Hull R. Retroid virus genome replication. Adv Virus Res. 1987;32:35-96. Review. PubMed
  • Halpern MS, McMahon SB, Mason WS, O'Connell AP. Viral antigen expression in the pancreas of DHBV-infected embryos and young ducks. Virology. 1986 Apr 15;150(1):276-82. PubMed
  • Lien JM, Aldrich CE, Mason WS. Evidence that a capped oligoribonucleotide is the primer for duck hepatitis B virus plus-strand DNA synthesis. J Virol. 1986 Jan;57(1):229-36. PubMed
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  • Halpern MS, McMahon S, Egan J, Aldrich CE, Mason WS, Ewert DL. Ablation of humoral immunity in 15I5 x 72 chickens is not predisposing to the formation of subgroup G virus-induced distal sarcomas. Virology. 1985 Oct 15;146(1):153-6. PubMed
  • Halpern MS, England JM, Flores L, Egan J, Newbold J, Mason WS. Individual cells in tissues of DHBV-infected ducks express antigens crossreactive with those on virus surface antigen particles and immature viral cores. Virology. 1984 Sep;137(2):408-13. PubMed
  • Molnar-Kimber KL, Summers JW, Mason WS. Mapping of the cohesive overlap of duck hepatitis B virus DNA and of the site of initiation of reverse transcription. J Virol. 1984 Jul;51(1):181-91. PubMed
  • Halpern MS, Ewert DL, Flores LJ, Fujita DJ, Aldrich CE, Mason WS. Sarcoma growth in 15I5 x 7(2) chickens infected with avian sarcoma viruses of subgroup B or G. Virology. 1984 Apr 30;134(2):472-6. PubMed
  • Halpern MS, Egan J, Mason WS, England JM. Viral antigen in endocrine cells of the pancreatic islets and adrenal cortex of Pekin ducks infected with duck hepatitis B virus. Virus Res. 1984;1(3):213-23. PubMed
  • Mason WS, Halpern MS, England JM, Seal G, Egan J, Coates L, Aldrich C, Summers J. Experimental transmission of duck hepatitis B virus. Virology. 1983 Dec;131(2):375-84. PubMed
  • Halpern MS, England JM, Deery DT, Petcu DJ, Mason WS, Molnar-Kimber KL. Viral nucleic acid synthesis and antigen accumulation in pancreas and kidney of Pekin ducks infected with duck hepatitis B virus. Proc Natl Acad Sci U S A. 1983 Aug;80(15):4865-9. PubMed
  • Halpern MS, Deery DT, Flores LJ, Fujita DJ, Mason WS. Differential reactivity of serum antibody from tumor-bearing 15I5 X 7(2) chickens for cross-reactive species of endogenous retroviral envelope glycoprotein. Virology. 1983 Jan 30;124(2):318-29. PubMed
  • Molnar-Kimber KL, Summers J, Taylor JM, Mason WS. Protein covalently bound to minus-strand DNA intermediates of duck hepatitis B virus. J Virol. 1983 Jan;45(1):165-72. PubMed
  • Mason WS, Aldrich C, Summers J, Taylor JM. Asymmetric replication of duck hepatitis B virus DNA in liver cells: Free minus-strand DNA. Proc Natl Acad Sci U S A. 1982 Jul;79(13):3997-4001. PubMed
  • Summers J, Mason WS. Replication of the genome of a hepatitis B--like virus by reverse transcription of an RNA intermediate. Cell. 1982 Jun;29(2):403-15. PubMed
  • Mason WS, Linial M, Hsu TW, Eisenman RN, Townsend J, Mark GE, Seal G, Aldrich C, Taylor JM. Alterations in the genomes of avian sarcoma viruses. Virology. 1982 Mar;117(2):456-74. PubMed
  • Hsu TW, Taylor JM, Aldrich C, Townsend JB, Seal G, Mason WS. Tandem duplication of the proviral DNA in an avian sarcoma virus-transformed quail clone. J Virol. 1981 Apr;38(1):219-23. PubMed
  • Halpern MS, Mason WS, Ewert DL, Deery DT, England JM. Expression of endogenous retroviral envelope antigen in Ig(+) B cells of immunized 15I5 X 71 chickens. J Immunol. 1981 Mar;126(3):1198-202. PubMed
  • Mason WS, Seal G, Summers J. Virus of Pekin ducks with structural and biological relatedness to human hepatitis B virus. J Virol. 1980 Dec;36(3):829-36. PubMed
  • Eisenman RN, Mason WS, Linial M. Synthesis and processing of polymerase proteins of wild-type and mutant avian retroviruses. J Virol. 1980 Oct;36(1):62-78. PubMed
  • Marini SC, Mason WS, England JM, Halpern MS. The induction of antibody reactivity to endogenous viral glycoprotein in 151(5) X 7(2) [chf(+), V(+)] chickens. Virology. 1980 Jan 30;100(2):488-91. PubMed
  • Taylor JM, Hsu TW, Yeater C, Mason WS. Synthesis and integration of avian sarcoma virus DNA. Cold Spring Harb Symp Quant Biol. 1980;44 Pt 2,:1091-6. PubMed
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1970 - 1979

  • Mason WS, Yeater C, Bosch JV, Wyke JA, Friis RR. Fourteen temperature-sensitive replication mutants of Rous sarcoma virus. Virology. 1979 Dec;99(2):226-40. PubMed
  • Mason WS, Hsu TW, Yeater C, Sabran JL, Mark GE, Kaji A, Taylor JM. Avian sarcoma virus-transformed quail clones defective in the production of focus-forming virus. J Virol. 1979 Apr;30(1):132-40. PubMed
  • Sabran JL, Hsu TW, Yeater C, Kaji A, Mason WS, Taylor JM. Analysis of integrated avian RNA tumor virus DNA in transformed chicken, duck and quail fibroblasts. J Virol. 1979 Jan;29(1):170-8. PubMed
  • Taylor JM, Mason WS, Hsu TW, Sabran JL, Yeater C, Mark GE, Kaji A, Guntaka RV, Lai MM. Avian RNA tumor virus DNA before and after integration into the host genome. Cold Spring Harb Symp Quant Biol. 1979;43 Pt 2:865-7. PubMed
  • Eisenman R, Shaikh R, Mason WS. Identification of an avian oncovirus polyprotein in uninfected chick cells. Cell. 1978 May;14(1):89-104. PubMed
  • Mason WS, Yeater C. A mutant of Rous sarcoma virus with a conditional defect in the determinant(s) of viral host range. Virology. 1977 Apr;77(2):443-56. PubMed
  • Wang L, Galehouse D, Mellon P, Duesberg P, Mason WS, Vogt PK. Mapping oligonucleotides of Rous sarcoma virus RNA that segregate with polymerase and group-specific antigen markers in recombinants. Proc Natl Acad Sci U S A. 1976 Nov;73(11):3952-6. PubMed
  • Blair DG, Mason WS, Hunter E, Vogt PK. Temperature-sensitive mutants of avian sarcoma viruses: genetic recombination between multiple or coordinate mutants and avian leukosis viruses. Virology. 1976 Nov;75(1):48-59. PubMed
  • Halpern MS, Bolognesi DP, Friis RR, Mason WS. Expression of the Major Viral Glycoprotein of Avian Tumor Virus in Cells of chf(+) Chicken Embryos. J Virol. 1975 May;15(5):1131-1140. PubMed
  • Friis RR, Mason WS, Chen YC, Halpern MS. A replication defective mutant of Rous sarcoma virus which fails to make a functional reverse transcriptase. Virology. 1975 Mar;64(1):49-62. PubMed
  • Baltimore D, Verma IM, Drost S, Mason WS. Temperature-sensitive DNA polymerase from Rous sarcoma virus mutants. Cancer. 1974 Oct;34(4 Suppl):suppl:1395-7. PubMed
  • Mason WS, Friis RR, Linial M, Vogt PK. Determination of the defective function in two mutants of Rous sarcoma virus. Virology. 1974 Oct;61(2):559-74. PubMed
  • Verma IM, Mason WS, Drost SD, Baltimore D. DNA polymerase activity from two temperature-sensitive mutants of Rous sarcoma virus is thermolabile. Nature. 1974 Sep 6;251(5470):27-31. PubMed
  • Linial M, Mason WS. Characterization of two conditional early mutants of Rous sarcoma virus. Virology. 1973 May;53(1):258-73. PubMed
  • Weiss RA, Mason WS, Vogt PK. Genetic recombinants and heterozygotes derived from endogenous and exogenous avian RNA tumor viruses. Virology. 1973 Apr;52(2):535-52. PubMed
  • Mason WS, Haselkorn R. Product of T4 gene 12. J Mol Biol. 1972 May 28;66(3):445-69. PubMed
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