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Radiation Synergism and Antagonism

  • Rex M. Tyrrell

Abstract

The above statement probably approaches the simplest definition of the wide variety of phenomena denoted as synergisms and antagonisms. A more careful description and qualification of these terms will be given in Sections 1.2 and 2.1. An enormous range of such interactions has been reported between chemicals, between chemicals and radiation, and between radiations at all levels of biological organization. Despite rising concern for the possible detrimental effects of industrial by-products (chemicals, heat, and even radiation) cast into the environment, relatively little attention has been given to the enormous potential that these agents may have for interacting with each other and with natural environmental agents (including chemicals and sunlight) to cause profound biological changes. Thus, interaction studies should form a basic part of environmental control programs. Until now experiments have been principally directed either toward medical and industrial applications, or to more fundamental problems of cellular function.

Keywords

Chromosome Aberration Linear Energy Transfer Chinese Hamster Cell Pyrimidine Dimer Diploid Yeast 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Achey, P., and Billen, D., 1969, Saturation of dark repair synthesis: Accumulation of strand breaks, Biophys. J. 9:647–653.Google Scholar
  2. Anderson, E. H., 1951, Heat reactivation of ultraviolet-inactivated bacteria,J. Bacteriol. 61:389–394.Google Scholar
  3. Anderson, T. F., and Duggar, B. M., 1939, The physiological changes produced in yeast by ultraviolet light and by heat (note), Science 90:358.Google Scholar
  4. Bain, J. A., Rusch, H. P., and Kline, B. E., 1943, The effect of temperature upon ultraviolet carcinogenesis with wavelengths 2800–3400 Å, Cancer Res. 3:610–612.Google Scholar
  5. Baptist, J. E., and Haynes, R. H., 1963, The oxygen effect in bacteria sensitized to X-rays by sublethal UV-photoproducts (abstract), Radiat. Res. 19:223.Google Scholar
  6. Baptist, J. E., and Haynes, R. H., 1972, The UV-X-ray synergism in Escherichia coli B/r. I. Inhibition by the incorporation of 5-bromouracil and by purine starvation, Photochem. Photobiol. 16:459–464.Google Scholar
  7. Barendson, G. W., Beusker, T. L. J., Vergroeson, A. J., and Budke, L., 1960, Effects of different ionizing radiations on human cells in tissue culture. II. Biological experiments, Radiat. Res. 13:841–849.Google Scholar
  8. Belli, J. A., and Bonté, F. J., 1963, Influence of temperature on the radiation response of mammalian cells in tissue culture, Radiat. Res. 18:272–276.Google Scholar
  9. Ben-Hur, E., and Elkind, M. M., 1974, Thermally enhanced radioresponse of cultured Chinese hamster cells: Damage and repair of single-stranded DNA and a DNA complex, Radiat. Res. 59:484–495.Google Scholar
  10. Ben-Hur, E., Bronk, B. V., and Elkind, M. M., 1972, Thermally enhanced radiosensitivity of cultured Chinese hamster cells, Nature (New Biology) 238:209–211.Google Scholar
  11. Ben-Hur, E., Elkind, M. M., and Bronk, B. V., 1974, Thermally enhanced radio-response of cultured Chinese hamster cells: Inhibition of repair of sub-lethal damage and enhancement of lethal damage, Radiat. Res. 58:38–51.Google Scholar
  12. Bhaumik, G. and Bhattacharjee, S. B., 1968, Interaction of X-ray and ultraviolet ray in killing cells, Nature 218:1077–1078.Google Scholar
  13. Blok, J., and Lohman, H., 1973, The effects of 7-radiation in DNA, Current topics in Radiation Research Quarterly 9:165–245.Google Scholar
  14. Blum, H. F., 1959, Carcinogenesis by Ultraviolet Light, Princeton University Press, Princeton, New Jersey.Google Scholar
  15. Bonura, T., and Smith, K. C., 1975, Enzymatic production of deoxyribonucleic acid double-strand breaks after ultraviolet irradiation of Escherichia coli, J. Bacteriol. 121:511–517.Google Scholar
  16. Boone, M. L. M., Leith, J. T., and Geraer, E. W., 1976, The interaction of hyperthermia and radiation (X-rays or accelerated helium ions) in tissue culture cells (abstract), Radiat. Res. 67:517.Google Scholar
  17. Bovie, W. T., and Daland, G. A., 1923, New experiments on the sensitization of protoplasm to heat by exposure to light of short wavelength, Amer. J. Physiol. 66:55–66.Google Scholar
  18. Bovie, W. T., and Klein, A., 1919, Sensitization to heat due to light of short wavelengths, J. Gen. Physiol. 1:331–336.Google Scholar
  19. Boyle, J. M., and Setlow, R. B., 1970, Correlation between host-cell reactivation and pyrimidine dimer excision in the DNA of bacteriophage A, J. Mol. Biol. 51:131–145.Google Scholar
  20. Bridges, B. A., Munson, R. J., Arlett, C. F., and Davies, D. R., 1967, Interaction between ultraviolet light and 7-radiation damage in the induction of mutants in Escherichia coli: The effect of some modifying treatments, J. Gen. Microbiol. 46:339–346.Google Scholar
  21. Bridges, B. A., Ashwood-Smith, M. J., and Munson, R. J., 1969a, Susceptibility of mild thermal and ionizing radiation damage to the same recovery mechanism in E. coli, Biochem. Biophys. Res. Commun. 35:193–196.Google Scholar
  22. Bridges, B. A., Ashwood-Smith, M. J., and Munson, R. J., 1967, Correlation of bacterial sensitivities to ionizing radiation and mild heating, J. Gen. Microbiol. 58:115–124.Google Scholar
  23. Bronk, B. V., 1976, Thermal potentiation of mammalian cell killing: Clues for understanding and potential for tumor therapy, in: Advances in Radiation Biology, Vol. 6 (J. T. Lett and H. E. Adler, eds.), pp. 267–325, Academic Press, New York.Google Scholar
  24. Brook, P. J., 1969, Stimulation of acospore release in Venturia inaequalis by far-red light, Nature 222:390–392.Google Scholar
  25. Brown, J. K., 1971, Chromosome aberrations in Chinese hamster cells following exposure to X-ray and ultraviolet radiation, in: Biophysical Aspects of Radiation Quality, Proceedings of IAEA Symposium, Vienna, pp. 273–286.Google Scholar
  26. Burns, F. J., Strickland, P., Vanderlaan, M., and Albert, R. E., 1976, The combined effect of ionizing radiation and ultraviolet light on tumor induction in rat skin (abstract), Radiat. Res. 67:629.Google Scholar
  27. Caspersson, T., Haglund, V., Lindell, B., and Zech, L., 1972, Radiation induced non-random chromosome breakage, Exp. Cell. Res. 71:541–543.Google Scholar
  28. Chaffee, R. R. J., and Musacchia, X. J., 1968, Study of the synergistic effects of heat exposure and ionizing irradiation in the hamster, Proc. Soc. Exp. Biol. Med. 129:718–720.Google Scholar
  29. Clarke, P. R., Hill, C. R., and Adams, K., 1970, Synergism between ultrasound and X-rays in tumour therapy, Brit. J. Radiol. 43:97–99.Google Scholar
  30. Clarkson, C. E., and Dewey, D. L., 1971, Recovery from UV damage in Serratia Marcescens (abstract), Stud. Biophys. 29:138.Google Scholar
  31. Coetzee, W. F., and Pollard, E. C., 1975, Near ultraviolet inactivation studies on Escherichia coli tryptophanase and tryptophan synthetase, Photochem. Photobiol. 22:29–32.Google Scholar
  32. Conger, A. D., 1948, The cytogenetic effect of sonic energy applied simultaneously with X-rays, Proc. Nat. Acad. Sci. USA 34:470–474.Google Scholar
  33. Cook, J. S., 1970, Photoreactivation in animal cells, in: Photophysiology, Vol. 5 (A. C. Giese, ed.), pp. 191–233, Academic Press, New York.Google Scholar
  34. Cooper, P. K., and Hannawalt, P. C., 1972a, Heterogeneity of patch size in repair replicated DNA in Escherichia coli, J. Mol. Biol. 67:1–10.Google Scholar
  35. Cooper, P. K., and Hannawalt, P. C., 1976, Role of DNA polymerase 1 and the rec system in excision repair in Escherichia coli, Proc. Nat. Acad. Sci. USA 69:1156–1160.Google Scholar
  36. Corry, P., Robinson, S., and Getz, S., 1976, The effect of hyperthermia of DNA repair in mammalian cells (abstract), Radiat. Res. 67:518–519.Google Scholar
  37. Crile, G., 1963, The effects of heat and radiation on cancers implanted on the feet of mice, Cancer Res. 23:372–380.Google Scholar
  38. Curran, H. R., and Evans, F. R., 1938, Sensitizing bacterial spores to heat by exposing them to ultraviolet light, J. Bacteriol. 36:455–465.Google Scholar
  39. Danpure, H. J., and Tyrrell, R. M., 1976, Oxygen-dependence of near-UV (365 nm) lethality and the interaction of near-UV and X-rays in two mammalian cell lines, Photochem. Photobiol. 23:171–177.Google Scholar
  40. Davies, D. R., Arlett, C. F., Munson, R. J., and Bridges, B. A., 1967, Interaction between ultraviolet light and gamma-radiation damage in the induction of mutants of Escherichia coli: The response in strains with normal and reduced ability to repair ultraviolet damage,J. Gen. Microbiol. 46:329–338.Google Scholar
  41. Dewey, W. C., Hopwood, L. E., Sapareto, S. A., and Gerweck, L. E., 1977, Cellular responses to combinations of hyperthermia and radiation, Radiology 123:463–474.Google Scholar
  42. Dietzel, F., Ringleb, D., Schneider, V., and Wricke, H., 1975, Microwaves in radiotherapy of tumours—Alternative to heavy particles? Strahlentherapie 149:438–441.Google Scholar
  43. DiPaolo, J. A., and Donovan, P. J., 1976, In vitro morphologic transformation of Syrian hamster cells by UV-irradiation is enhanced by X-irradiation and unaffected by chemical carcinogens, Int. J. Radiat. Biol. 30:41–53.Google Scholar
  44. Doneson, I. N., and Shankel, D. M., 1964, Mutational synergism between radiations and methylated purines in Escherichia coli, J. Bacteriol. 87:61–67.Google Scholar
  45. Drake, J. W., and Baltz, R. H., 1976, The biochemistry of mutagenesis, Annu. Rev. Biochem. 45:11–37.Google Scholar
  46. Dugan, V. L., and Trujillo, R., 1975, Heat accelerated radioinactivation of attenuated poliovirus, Radiat. Environ. Biophys. 12:187–195.Google Scholar
  47. Durban, E., and Grecz, N., 1969, Resistance of spores of Clostridium botulinum 33A to combinations of ultraviolet and gamma rays, Appl. Microbiol. 18:44–50.Google Scholar
  48. Eichhorn, H. J., and Lessel, A., 1976, A comparison between combined neutron- and telecobalt-therapy with telecobalt therapy alone for cancer of the bronchus, Brit. J. Radiol. 49:880–882.Google Scholar
  49. Eisenstark, A., 1971, Mutagenic and lethal effects of visible and near-ultraviolet light on bacterial cells, in: Advances in Genetics, Vol. 12 (E. W. Caspari, ed.), pp. 167–198, Academic Press, New York.Google Scholar
  50. Elkind, M. M., and Kamper, C., 1970, Two forms of repair of DNA in mammalian cells following irradiation, Biophys. J. 10:237–245.Google Scholar
  51. Elkind, M. M., and Sutton, H., 1958, Ultraviolet mitigation of X-ray lethality in dividing yeast cells, Science 128:1082–1083.Google Scholar
  52. Elkind, M. M., and Sutton, H., 1959, Sites of lethal irradiation: Overlap in sites for X-ray, ultraviolet, photoreactivation, and ultraviolet protection and reactivation in dividing yeasts, Radiat. Res. 10:296–312.Google Scholar
  53. Epstein, J. H., 1970, Ultraviolet carcinogenesis, in: Photophysiology, Vol. 5 (A. C. Giese, ed.), pp. 235–273, Academic Press, New York.Google Scholar
  54. Evans, H. J., 1962, Chromosome aberrations induced by ionizing radiations, in: International Review of Cytology, Vol. 13 (G. H. Bourne and J. F. Danieli, eds.), pp. 221–321, Academic Press, New York.Google Scholar
  55. Evans, H. J., 1971, Use of chromosome aberration frequencies for biological dosimetry in man, in: Advances in Physical and Biological Radiation Detectors, pp. 593–609, Proceedings of IAEA symposium, Vienna.Google Scholar
  56. Evans, T. C., Goodrich, J. P., and Slaughter, J. C., 1941, Radiosensitivity of skin of new-born rats. III. Sensitivity at different temperatures, Proc. Soc. Exp. Biol. Med. 47:434–437.Google Scholar
  57. Evans, R. G., and Norman, A., 1968a, Unscheduled incorporation of thymidine in ultraviolet-irradiated human lymphocytes, Radiat. Res. 36:287–298.Google Scholar
  58. Evans, R. G., and Norman, A., 1968b, Radiation stimulated incorporation of thymidine into the DNA of human lymphocytes, Nature 217:455.Google Scholar
  59. Evans, W. E., and Parry, J. M., 1974, Isolation, genetics and survival characteristics of thermosensitive mutants of yeast, Mol. Gen. Genet. 134:333–344.Google Scholar
  60. Forbes, H. S., and Daland, G. A., 1923, Further experiments on the sensitization to heat due to exposure of short wavelengths, Amer. J. Physiol. 66:50–54.Google Scholar
  61. Forbes, P. D., 1972, Effects of long wave ultraviolet light on the skin of mice, in: Book of Abstracts, Sixth International Congress of Photobiology, Bochum, p. 343.Google Scholar
  62. Forbes, P. D., 1973, Influence of long wave UV on photocarcinogenesis, in: Book of Abstracts, First Ann. Meeting American Society for Photobiology, Sarasota, p. 136.Google Scholar
  63. Freeman, R. G., and Knox, J. M., 1964, Influence of temperature on ultraviolet injury, Arch. Dermatol. 89:858–864.Google Scholar
  64. Gamaleya, N., 1972, Lasers in Experiment and Clinic (in Russian), Medicina, Moscow.Google Scholar
  65. Gerweck, L. E., Gillette, E. L., and Dewey, W. C., 1974, Killing of Chinese hamster cells in vitro by heating under hypoxic or aerobic conditions, Eur. J. Cancer 10:691–693.Google Scholar
  66. Gerweck, L. E., Gillette, E. L., and Dewey, W. C., 1975, Effect of heat and radiation on synchronous Chinese hamster cells: Killing and repair, Radiat. Res. 64:611–623.Google Scholar
  67. Giese, A. C., and Grossman, E. B., 1946, The action spectrum of sensitization to heat with ultraviolet, J. Gen. Physiol. 29:79–87.Google Scholar
  68. Giovanella, B. C., Morgan, A. C., Stehlin, J. S., and Williams, L. J., 1973, Selected lethal effect of supranormal temperature on mouse sarcoma cells, Cancer Res. 33:2568–2578.Google Scholar
  69. Glass, H. B., 1950, The effects of supplementary treatment with infrared radiation on X-ray induced lethals and chromosome aberrations in females of Drosophila melanogaster, Genetics 35:109–110.Google Scholar
  70. Goldman, L., 1967, Biomedical Aspects of the Laser, Springer Verlag, New York.Google Scholar
  71. Gordon, S. A., and Surrey, K., 1960, Red and far-red action on oxidative phosphorylation, Radiat. Res. 12:325–339.Google Scholar
  72. Gordon, S. A., Stroud, A. N., and Chen, C. H., 1971, The induction of chromosomal aberrations in pig kidney cells by far-red light, Radiat. Res. 45:274–287.Google Scholar
  73. Griggs, H. G., and Bender, M. A., 1973, Photoreactivation of ultraviolet-induced chromosomal aberrations, Science 179:86–88.Google Scholar
  74. Grossman, L., 1972, Enzymes involved in the repair of DNA, Advan. Radiat. Biol. 4:77–129.Google Scholar
  75. Hahn, E. W., Canada, T. R., Alfieri, A. A., and McDonald, J. C., 1974a, The radiation enhancement factor (REF) of hyperthermia in combination with fast neutrons in local tumor responses (abstract), Radiat. Res. 59:141.Google Scholar
  76. Hahn, E. W., Feingold, S. M., and Kim, J. H., 1976, The effect of radiation and hyperthermia on growing bone (abstract), Radiat. Res. 59:186.Google Scholar
  77. Hahn, E. W., Canada, T. R., Alfieri, A. A., and McDonald, J. C., 1976, The interaction of hyperthermia with fast neutrons or X-rays on local tumor response, Radiat. Res. 68:39–56.Google Scholar
  78. Hahn, G. M., 1974, Metabolic aspects of the role of hyperthermia in mammalian cell inactivation and their possible relevance to cancer treatment, Cancer Res. 34:3117–3123.Google Scholar
  79. Hakkinen, A. M., Blomquist, K., Spring, E., and Valtonen, E., 1975, Simultaneous application of pulsed high frequency currents and gamma-rays to cultured melanoma cells, Strahlentherapie 149:205–207.Google Scholar
  80. Hariharan, P. V., Remsen, J. F., and Cerutti, P. A., 1975, Excision repair of X-ray damaged thymine in bacterial and mammalian systems, in: Molecular Mechanisms for Repair of DNA, Part A (P. C. Hannawalt and R. B. Setlow, eds.), pp. 51–61, Plenum Press, New York.Google Scholar
  81. Harisiadis, L., Hall, E. J., Krajevic, U., and Borek, C., 1975, Hyperthermia: Biological studies at the cellular level, Radiology 117:447–452.Google Scholar
  82. Har-Kedar, I., and Bleehan, N. M., 1976, Experimental and clinical aspects of hyperthermia applied to the treatment of cancer with special reference to the role of ultrasonic and microwave heating, in: Advances in Radiation Biology, Vol. 6 (J. T. Lett and H. E. Adler, eds.), pp. 229–267, Academic Press, New York.Google Scholar
  83. Harm, W., 1968a, Effects of dose fractionation on ultraviolet survival of Escherichia coli, Photochem. Photobiol. 7:73–86.Google Scholar
  84. Harm, W., 1968b, Dark repair of photorepairable UV lesions in Escherichia coli, Mutat. Res. 6:25–35.Google Scholar
  85. Hartmann, K. M., 1967, Action spectrum of photomorphogenesis under high energy conditions and its interpretation on the basis of phytochrome. Hypocotyl growth inhibition in Lactuca sativa, Z. Naturforsch 226:1172–1175.Google Scholar
  86. Hausser, I., 1938, Uber spezifisch Wirkunger des Langwelligan ultra-violetten Lichts auf die menschliche Haut, Strahlentherapie 62:315–322.Google Scholar
  87. Hausser, K. W., and von Ohmcke, H., 1933, Lichtbräunung an Fruchtschalen, Strahlentherapie 48:223–229.Google Scholar
  88. Haynes, R. H., 1962, Reciprocal sensitization of E. coli by ionizing and ultraviolet radiation (abstract), Radiat. Res. 16:562–563.Google Scholar
  89. Haynes, R. H., 1964a, Molecular localization of radiation damage relevant to bacterial inactivation, in: Physical Processes in Radiation Biology (L. Augenstein, R. Mason, and B. Rosenburg, eds.), pp. 51–72, Academic Press, New York.Google Scholar
  90. Haynes, R. H., 1964b, Role of DNA repair mechanism in microbial inactivation and recovery phenomena, Photochem. Photobiol. 3:429–450.Google Scholar
  91. Haynes, R. H., 1966, The interpretation of microbial inactivation and recovery phenomena, Radiat. Res. 6(suppl.):1–29.Google Scholar
  92. Heaslip, M. B., 1967, Radiosensitivity of deciduous tree seeds to different ratios of fast neutron and gamma radiations, Radiat. Bot. 7:415–428.Google Scholar
  93. Helsper, J. T., Sharp, G. S., and Rounds, D. E., 1967, The synergistic effect of laser radiation and ionizing radiation on malignant tumors in vivo and in vitro, Amer. J. Roentgenol. 99:446–449.Google Scholar
  94. Hendricks, S. B., and Borthwick, H. A., 1965, Physiological functions of phytochrome, in: Chemistry and Biochemistry of Plant Pigments (T. W. Goodwin, ed.), pp. 405–436, Academic Press, New York.Google Scholar
  95. Henle, K. J., and Leeper, D. B., 1976, Interaction of hyperthermia and radiation in CHO cells: recovery kinetics, Radiat. Res. 66:505–518.Google Scholar
  96. Hill, L., and Eidenow, A., 1923, Biological action of light. 1. The influence of temperature, Proc. Roy. Soc. Biol. 95:163–180.Google Scholar
  97. Hill, R. F., 1958, Independent inactivation of bacteriophage TI by X-rays and ultraviolet light, Radiat. Res. 8:46–50.Google Scholar
  98. Holmberg, M., 1974, No interaction between UV and X-irradiation on chromosome aberrations in cells with Trisomy 21, Nature 249:448–449.Google Scholar
  99. Holmberg, M., 1976, Lack of synergistic effect between X-rays and UV-radiation on the frequency of chromosome aberrations in phyto-haemaglutin stimulated human lymphocytes in the G1 stage, Mutant. Res. 34:141–148.Google Scholar
  100. Holmberg, M., and Jonasson, J., 1973, Preferential location of X-ray induced chromosome breakage in the R-bands of human chromosomes, Hereditas 74:57–57.Google Scholar
  101. Holmberg, M., and Jonasson, J., 1974, Synergistic effect of X-ray and UV irradiation on the frequency of chromosome breakage in human lymphocytes, Mutat. Res. 23:213–221.Google Scholar
  102. Hoye, R., Gart, J., Weiss, G., Riggle, G., and Ketcham, A., 1967, Potentiation of laser oncolysis with pre-treatment X-irradiation, Radiat. Res. 32:112–116.Google Scholar
  103. Jagger, J., 1958, Photoreactivation, Bacteriol. Rev. 22:99–142.Google Scholar
  104. Jagger, J., 1960, Photoreactivation, in: Radiation Protection and Recovery (A. Hollaender, ed.), pp. 352–377, Pergamon Press, New York.Google Scholar
  105. Jagger, J., 1967, Introduction to Research in Ultraviolet Photobiology, Prentice-Hall, Inc., Englewood Cliffs, New Jersey.Google Scholar
  106. Jagger, J., Curtis Wise, W., and Stafford, R. S., 1964, Delay in growth and division induced by near ultraviolet radiation in Escherichia coli B and its role in photoprotection and liquid holding recovery, Photochem. Photobiol. 3:11–24.Google Scholar
  107. Javish, J., 1966, Distributions of chromosome damage in irradiated Chinese hamster cell cultures (abstract), Radiat. Res. 27:493.Google Scholar
  108. Johns, H. E., Rapaport, S. A., and Delbruck, M., 1962, Photochemistry of thymine dimers, J. Mol. Biol. 4:104–114.Google Scholar
  109. Joshi, D. S., Van der Schueren, E., Deys, B. F., and Barendsen, G. W., 1978, Differences in sensitivity of two cell lines to hyperthermic treatment, in press.Google Scholar
  110. Kada, T., Doudney, C. O., and Haas, F. L., 1966, Mutation frequency response of irradiated bacteria to a second radiation exposure, Mutat. Res. 3:118–128.Google Scholar
  111. Karam, J. D., and Speyer, J. F., 1970, Reversible inactivation of T4 ts DNA polymerase mutants in vivo, Virology 43:196–203.Google Scholar
  112. Kaufman, B. P., and Hollaender, A., 1946, Modification of the frequency of chromosome rearrangements induced by X-rays in Drosophila. II. Use of ultraviolet radiation, Genetics 31:368–376.Google Scholar
  113. Kaufman, B. P., and Wilson, K., 1949, Modification of the frequency of chromosomal rearrangements induced by X-rays in Drosophila. IV. Post-treatment with near-infrared radiation, Genetics 34:425–436.Google Scholar
  114. Kaufman, B. P., Hollaender, A., and Gay, H., 1946, Modification of frequency of chromosomal re-arrangements induced by X-rays in Drosophila. I. Use of near-infrared radiation, Genetics 31:349–367.Google Scholar
  115. Kim, J. H., Kim, S. H., and Hahn, E., 1974, Thermal enhancement of the radiosensitivity using cultured normal and neoplastic cells, Amer. J. Roentgenol. 121:860–864.Google Scholar
  116. Kirby-Smith, J. S., 1963, Effects of combined ultraviolet and X-irradiation on chromosome breakage in Tradescantia pollen, in: Radiation Induced Chromosome Aberrations (S. Wolff ed.), pp. 203–214, Columbia University Press, New York.Google Scholar
  117. Kittler, L., and Löber, G., 1977, Photochemistry of the nucleic acids, in: Photochemical and Photobiological Reviews, Vol. 2 (K. C. Smith, ed.), pp. 39–131, Plenum Press, New York.Google Scholar
  118. Klein, R. M., and Klein, D. T., 1962, Interaction of ionizing and visible radiation in mutation induction in Neurospora crassa, Amer. J. Bot. 49:870–874.Google Scholar
  119. Lakchaura, B. D., 1972, Photoprotection from killing in UV sensitive E. coli K-12 mutants: Involvement of excision-resynthesis repair, Photochem. Photobiol. 16:197–202.Google Scholar
  120. Lakchaura, B., and Clarke, J. B., 1969, Photoprotection against nitrogen mustard inactivation in E. coli B, Photochem. Photobiol. 10:221–225.Google Scholar
  121. Lea, D. E., 1955, Actions of Radiation on Living Cells, 2nd ed., Cambridge University Press, New York.Google Scholar
  122. Lehmann, J. F., and Krusen, F. H., 1955, Biophysical effects of ultrasonic energy on carcinoma and their possible significance, Arch. Phys. Med. Rehabil. 36:452–459.Google Scholar
  123. Levine, E. M., and Robbins, E. B., 1970, Differential temperature sensitivity of normal and cancer cells in culture, J. Cell Physiol. 76:373–379.Google Scholar
  124. Lewis, N. F., Shah, A. R., and Kumta, U. S., 1975, Synergistic killing effect in pre-UV-irradiated Micrococcus radiophilus, Photochem. Photobiol. 22:145–146.Google Scholar
  125. Ley, R. D., 1973, Post-replication repair in an excision-defective mutant of Escherichia coli: Ultraviolet light-induced incorporation of bromodeoxyuridine into parental DNA, Photochem. Photobiol. 18:87–95.Google Scholar
  126. Lindahl, T., 1976, New class of enzymes acting on damaged DNA, Nature 259:64–66.Google Scholar
  127. Lipson, R. L., and Baldes, E. J., 1960, Photosensitivity and heat, Arch. Dermatol. 82:517–520.Google Scholar
  128. Luckiesh, M., 1946, Applications of Germicidal, Erythemal and Infrared Energy, D. Van Nostrand Company, New York.Google Scholar
  129. Ma, T. H., and Wolff, S., 1965, Far-red induced mitotic delay and the apparent increase of X-ray induced chromatid aberrations in Tradescantia microspores, Radiat. Bot. 5:293–298.Google Scholar
  130. Mackay, D., Eisenstark, A., Webb, R. B., and Brown, M. S., 1976, Action spectra for lethality in recombination-less strains of Salmonella typhimurium and Escherichia coli, Photochem. Photobiol. 24:337–345.Google Scholar
  131. Marsden, H. S., Pollard, E. C., Ginoza, W., and Randall, E. P., 1974, Involvement of recA and exr genes in the in vivo inhibition of the RecBC nuclease, J. Bacteriol. 118:465–470.Google Scholar
  132. Martignoni, K. D., and Smith, K. C., 1973, The synergistic action of UV and X-radiation on mutants of Escherichia coli strain K-12, Photochem. Photobiol. 18:1–8.Google Scholar
  133. McGuff, P., 1966, Surgical Applications of Laser, Springfield, Boston.Google Scholar
  134. McGuff, P. E., Gottlieb, L. S., Katayama, I., and Levy, C. K., 1966, Comparative study of effects of laser and/or ionizing radiation therapy on experimental or human malignant tumors, Amer. J. Roentgenol. 96:744–748.Google Scholar
  135. Miller, R. C., Leith, J. T., Veomett, R. C., and Gerner, E. W., 1976, Potentiation of radiation myelitis in rats by hyperthermia, Brit. J. Radiol. 49:895–896.Google Scholar
  136. Mitrakos, K., and Shropshire, W. (eds.), 1972, Phytochrome, Academic Press, New York.Google Scholar
  137. Moh, C. C., and Withrow, R. B., 1959, Non-ionizing radiant energy as an agent in altering the incidence of X-ray-induced chromatid aberrations. II. Reversal of the far-red potentiating effect in Vicia by red radiant energy, Radiat. Res. 10:13–19.Google Scholar
  138. Mosely, B. E. B., and Laser, H., 1965, Similarity of repair of ionizing and ultraviolet radiation damage in Micrococcus radiodurans, Nature 206:373–375.Google Scholar
  139. Moskalik, K. G., and Pertsov, O. L., 1975, On the enhancement of oncolytic effect of laser radiation by means of fast electrons, Neoplasma 22:355–360.Google Scholar
  140. Moss, S. H., and Davies, D. J. G., 1974, Interrelationship of repair mechanisms in ultraviolet irradiated Escherichia coli, J. Bacteriol. 120:15–23.Google Scholar
  141. Murphy, M. S. S., Madhvanath, U., Subrahmanyam, P., Rao, B. S., and Reddy, N. M. S., 1975, Synergistic effect of simultaneous exposure to 60Co gamma rays and 210Po alpha rays in diploid yeast, Radiat. Res. 63:185–190.Google Scholar
  142. Neary, G. J., 1969, Cell killing, repair and radiation quality, Stud. Biophys. 18:11–25.Google Scholar
  143. Neary, G. J., Bance, D. A., Cox, R., Preston, R. J., Richards, V., Stephens, M. A., Stretch, A., and Wilkinson, R. E., 1974, A synergistic interaction between UV and protons in causing loss of reproductive capacity in Escherichia coli B/r, Int. J. Radiat. Biol. 26:187–192.Google Scholar
  144. Okuda, A., 1972, Studies of liquid-holding recovery of E. coli B/r by means of synergistic interaction between ultraviolet light and ionizing radiation (abstract), J. Radiat. Res. 13:47–48.Google Scholar
  145. Okuda, A., 1973, Inhibition of the UV-ionizing radiation synergism in Escherichia coli B/r by liquid holding between the two irradiations, Photochem. Photobiol. 18:335–337.Google Scholar
  146. Okuda, A., 1974a, Effects of ionizing radiation on recovery from ultraviolet inactivation in Escherichia coli B/r, J. Radiat. Res. 15:144–147.Google Scholar
  147. Okuda, A., 1974b, Effects of mild heating on recovery from ultraviolet inactivation in Escherichia coli B/r. I. Inhibition of excision of pyrimidine dimers, J. Radiat. Res. 15:132–139.Google Scholar
  148. Okuda, A., 1974c, Effects of mild heating on recovery from ultraviolet inactivation in Escherichia coli B/r. II. Removal of heat-induced effects by subsequent incubation, J. Radiat. Res. 15:140–143.Google Scholar
  149. Overgaard, J., and Overgaard, K., 1975, Effect of environmental acidity on the hyperthermic treatment of tumor cells, IRCS Med. Sci. 3:386–387.Google Scholar
  150. Overgaard, K., and Overgaard, J., 1972a, Investigations on the possibility of a thermic tumour therapy. I. Short-wave treatment of a transplanted isologous mouse mammary carcinoma, Eur. J. Cancer 8:65–68.Google Scholar
  151. Overgaard, K., and Overgaard, J., 1972b, Investigations on the possibility of thermic tumour therapy. II. Action of combined heat-roentgen treatment on a transplanted mouse mammary carcinoma, Eur. J. Cancer 8:573–575.Google Scholar
  152. Palzer, R. J., and Heidelburger, C., 1973, Influence of drugs and synchrony on the hyperthermic killing of Hela cells, Cancer Res. 33:415–421.Google Scholar
  153. Paribok, V. P., Valdstein, E. A., and Zhestjanikov, V. D., 1965, Post-irradiation recovery of E. coli ‘B’ after X and α-irradiation in oxygen or nitrogen, Nature 206:525–526.Google Scholar
  154. Patrick, M. H., and Haynes, R. H., 1964, Dark recovery phenomenon in yeast. II. Conditions that modify the recovery process, Radiat. Res. 23:564–579.Google Scholar
  155. Peak, M. J., and Tyrrell, R. M. 1976, Interaction between different near-ultraviolet wavelengths in the inactivation of E. coli, in: Book of Abstracts, 7th Int. Congr. on Photobiology, Rome, p. 353.Google Scholar
  156. Peak, M. J., Peak, J. G., and Webb, R. B., 1975, Synergism between different near-ultraviolet wavelengths in the inactivation of transforming DNA, Photochem. Photobiol. 21:129–131.Google Scholar
  157. Pollard, E. C., and Randall, E. P., 1973, Studies on the inducible inhibitor of radiation-induced DNA degradation of Escherichia coli, Radiat. Res. 55:265–279.Google Scholar
  158. Radman, M., 1975, SOS Repair hypothesis: Phenomenology of an inducible DNA repair which is accompanied by mutagenesis, in: Molecular Mechanisms for Repair of DNA, Part A (P. C. Hannawalt and R. B. Setlow, eds.), pp. 347–355, Plenum Press, New York.Google Scholar
  159. Railton, R., Lawson, R. C., and Porter, D., 1975, Interaction of 7-ray and neutron effects on the proliferative capacity of Chinese hamster cells, Int. J. Radiat. Biol. 27:75–82.Google Scholar
  160. Ramabhadran, T. V., and Jagger, J., 1975, Evidence against DNA as the target for 334nm-induced growth delay in Escherichia coli, Photochem. Photobiol. 21:227–233.Google Scholar
  161. Ranade, S. S., Avadhani, N. G., and Rege, D. V., 1974, Effects of non-ionizing and ionizing radiations on the transforming ability of E. coli DNA, Photochem. Photobiol. 19:103–108.Google Scholar
  162. Robinson, J. E., Wizenberg, M. J., and McCready, W. A., 1974, Combined hyperthermia and radiation suggest an alternative to heavy particle therapy for reduced oxygen enhancement ratios, Nature 251:521–522.Google Scholar
  163. Rounds, D., and Boher, J., 1964, The combined effect of ruby laser and gamma radiation on an established cell line in vitro, J. Cell Biol. 23:80A.Google Scholar
  164. Rupert, C. S., and Harm, W., 1966, Reactivation after photobiological damage, in: Advances in Radiation Biology, Vol. 2 (L. G. Augenstein, R. Mason, and M. R. Zelle, eds.), pp. 1–81, Academic Press, New York.Google Scholar
  165. Rupp, W. D., and Howard-Flanders, P., 1968, Discontinuities in the DNA synthesized in an excision-defective strain of Escherichia coli following ultraviolet irradiation, J. Mol. Biol. 31:291–304.Google Scholar
  166. Rupp, W. D., Wilde, C. E., Reno, D. L., and Howard-Flanders, P., 1971, Exchanges between DNA strands in ultraviolet-irradiated Escherichia coli, J. Mol. Biol. 61:25–44.Google Scholar
  167. Sapora, O., Simone, G., and Quintiliani, M., 1973, DNA repair and degradation in X-irradiated E. coli B/r cells after treatment with ultraviolet light and N-ethyl maleimide, Int. J. Radiat. Biol. 24:99–105.Google Scholar
  168. Saracheck, A., and Lucke, W. H., 1953, Induction of resistance to X-ray inactivation in Saccharomyces by pre-exposure to 2537Å ultraviolet radiation, Experientia 9:374–376.Google Scholar
  169. Sedgwick, S. G., 1976, Misrepair of overlapping daughter strand gaps as a possible mechanism for UV induced mutagenesis in UVR strains of Escherichia coli: A general model for induced mutagenesis by misrepair (SOS) repair of closely spaced DNA lesions, Mutat. Res. 41:185–201.Google Scholar
  170. Sedgwick, S. G., and Bridges, B. A., 1972, Evidence for indirect production of DNA strand excisions during mild heating of E. coli, J. Gen. Microbiol. 71:191–193.Google Scholar
  171. Setlow, J. K., 1967, The effects of ultraviolet radiation and photoreactivation, in: Comprehensive Biochemistry, Vol. 27, Photobiology and Ionizing Radiations (M. Florkin and E. H. Stotz, eds.), pp. 157–209, Elsevier, Amsterdam.Google Scholar
  172. Setlow, R. B., 1964, Physical changes and mutagenesis, J. Cell. Comp. Physiol. 64(suppl. 1): 51–68.Google Scholar
  173. Setlow, R. B., 1973, The relevance of photobiological repair, An. Acad. Brasil. Cienc. 45(suppl.):215–221.Google Scholar
  174. Setlow, R. B., and Setlow, J. K., 1962, Evidence that UV induced thymine dimers in DNA cause biological damage, Proc. Nat. Acad. Sci. USA 48:1250–1257.Google Scholar
  175. Setlow, R. B., and Setlow, J. K., 1972, Effects of radiation on polynucleotides, Annu. Rev. Biophys. Bioeng. 1:293–346.Google Scholar
  176. Sideropoulos, A. S., Johnson, R. C., and Shankel, D. M., 1968, Mutational synergism between heat and sublethal dosages of ultraviolet light in Escherichia coli strains, J. Bacteriol. 95:1486–1488.Google Scholar
  177. Smith, K. C., 1964, Photochemistry of the nucleic acids, in: Photophysiology, Vol. 2 (A. C. Giese, ed.), pp. 329–388, Academic Press, New York.Google Scholar
  178. Smith, K. C., 1971, The roles of genetic recombination and DNA polymerase in the repair of damaged DNA, in: Photophysiology, Vol. 6 (A. C. Giese, ed.), pp. 209–278, Academic Press, New York.Google Scholar
  179. Smith, K. C., and Ganeson, A. K., 1966, The apparent protection of Escherichia coli Bs from lethal effects of X-irradiation by prior exposure to ultraviolet radiation, Radiat. Res. 6(suppl.):218–219.Google Scholar
  180. Smith, K. C., and Martignoni, K. D., 1973, Prior irradiation can sensitize or protect bacterial cells from subsequent irradiation: A genetic and biochemical study, An. Acad. Brasil. Cienc. 45(suppl.):135–145.Google Scholar
  181. Smith, K. C., and Martignoni, K. D., 1976, Protection of Escherichia coli cells from ultraviolet and X-irradiation by prior X-irradiation: A genetic and physiological study, Photochem. Photobiol. 24:515–525.Google Scholar
  182. Stapleton, G. E., and Edington, C. W., 1956, Temperature dependence of bacterial inactivation by X-rays, Radiat. Res. 5:39–45.Google Scholar
  183. Sutherland, B. M., 1974, Photoreactivation enzyme from human leucocytes, Nature 248:109–112.Google Scholar
  184. Swanson, C. P., 1944, X-ray and ultraviolet studies on pollen tube chromosomes. I. The effect of ultraviolet (2537 Â) on X-ray-induced chromosomal aberrations, Genetics 29:61–68.Google Scholar
  185. Swanson, C. P., 1947, The effect of infrared treatment on the production of X-ray induced changes in the chromosomes of Tradescantia, Amer. J. Bot. 34:12a.Google Scholar
  186. Swanson, C. P., 1949, Further studies on the effect of infrared radiations on X-ray induced chromatid aberrations in Tradescantia, Proc. Nat. Acad. Sci. USA 35:237–244.Google Scholar
  187. Swanson, C. P., 1952, The effect of supplementary factors on the radiation-induced frequency of mutations in Aspergillus terreus, J. Cell. Comp. Physiol. 39(suppl. l):27–38.Google Scholar
  188. Swanson, C. P., and Hollaender, A., 1946, The frequency of X-ray induced chromatic breaks in Tradescantia as modified by near infrared radiation, Proc. Nat. Acad. Sci. USA 32:295–302.Google Scholar
  189. Swanson, C. P., and Yost, H. T., 1951, The induction of activated stable states in the chromosomes of Tradescantia by infrared and X-rays, Proc. Nat. Acad. Sci. USA 37:796–802.Google Scholar
  190. Swenson, P. A., 1976, Physiological responses of Escherichia coli to far-ultraviolet radiation, in: Photochemical and Photobiological Reviews, Vol. 1 (K. C. Smith, ed.), pp. 268–387, Plenum Press, New York.Google Scholar
  191. Swenson, P. A., Boyle, J. M., and Schenley, R. L., 1974, Thermal reactivation of ultraviolet-irradiated Escherichia coli: Relationship to respiration, Photochem. Photobiol. 19: 1–9.Google Scholar
  192. Tan, K. K., 1974a, Complete reversibility of sporulation by near ultraviolet and blue light in Botrytis cinerea, Trans. Brit. Mycol. Soc. 63:203–205.Google Scholar
  193. Tan, K. K., 1974b, Blue light inhibition of sporulation in Botrytis cinerea, J. Gen. Microbiol. 82:191–200.Google Scholar
  194. Tan, K. K., 1974c, Red-far-red reversible photoreaction in the recovery from blue light inhibition of sporulation in Botrytis cinerea, J. Gen. Microbiol. 82:201–202.Google Scholar
  195. Tan, K. K., 1975a, Recovery from blue light inhibition of sporulation in Botrytis cinerea, Trans. Brit. Mycol. Soc. 64:225–230.Google Scholar
  196. Tan, K. K., 1975b, Interaction of near-ultraviolet, blue, red, and far-red light in sporulation of Botrytis cinerea, Trans. Brit. Mycol. Soc. 64:215–222.Google Scholar
  197. Thrall, D. E., Gillette, E. L., and Dewey, W. C., 1975, Effect of heat and ionizing radiation on normal and neoplastic tissue of the C3H mouse, Radiat. Res. 63:363–377.Google Scholar
  198. Thrall, D. E., Gerweck, L. E., Gillette, E. L., and Dewey, W. C., 1976, Response of cells in vitro and tissues in vivo to hyperthermia and X-irradiation, in: Advances in Radiation Biology, Vol. 6 (J. T. Lett and H. Adler, eds.), pp. 211–227, Academic Press, New York.Google Scholar
  199. Todd, P., and Schroy, C. B., 1974, X-ray inactivation of cultured mammalian cells: Enhancement by ultrasound, Radiology 113:445–447.Google Scholar
  200. Tolun, A., Christensen, R., and. Pollard, E. C., 1974, Repair of radiation-induced strand breaks as related to the inducible inhibitor of post-irradiation DNA degradation, Biophys. J. 14:691–697.Google Scholar
  201. Town, C. D., Smith, K. C., and Kaplan, H. S., 1971, Rapid repair of X-ray induced DNA strand breaks in E. coli K-12 and its absence in a mutant lacking DNA polymerase, Science 172:851–853.Google Scholar
  202. Trujillo, R., and Dugan, V. L., 1972, Synergistic inactivation of viruses by heat and ionizing radiation, Biophys. J. 12:92–113.Google Scholar
  203. Tyrrell, R. M., 1973, Induction of pyrimidine dimers in bacterial DNA by 365 nm radiation, Photochem. Photobiol. 17:69–73.Google Scholar
  204. Tyrrell, R. M., 1974, The interaction of near-UV (365 nm) and X-irradiations on wild type and repair-deficient strains of Escherichia coli K-12: Physical and biological measurements, Int. J. Radiat. Biol. 25:373–390.Google Scholar
  205. Tyrrell, R. M., 1976a, RecA + -dependent synergism between 365 nm and ionizing radiation in log-phase Escherichia coli: A model for oxygen-dependent near-UV inactivation by disruption of DNA repair, Photochem. Photobiol. 23:13–20.Google Scholar
  206. Tyrrell, R. M., 1976b, Synergistic lethal action of ultraviolet-violet radiations and mild heat in Escherichia coli, Photochem. Photobiol. 24:345–351.Google Scholar
  207. Tyrrell, R. M., and R. B. Webb, 1973, Reduced dimer excision in bacteria following near-ultraviolet (365 nm) radiation, Mutat. Res. 19:361–364.Google Scholar
  208. Tyrrell, R. M., Webb, R. B., and Brown, M. S., 1973, Destruction of the photoreactivating enzyme by 365 nm radiation, Photochem. Photobiol. 18:249–254.Google Scholar
  209. Tyrrell, R. M., Ley, R. D., and Webb, R. B., 1974, Induction of single strand breaks (alkali-labile bonds) in bacterial and phage DNA by near-UV (365 nm) radiation, Photochem. Photobiol. 20:395–399.Google Scholar
  210. Urbach, F., (ed.), 1969, The Biologic Effects of Ultraviolet Radiation (with emphasis on the skin), Pergamon Press, Oxford.Google Scholar
  211. Urbach, F., Epstein, J. M., and Forbes, P. D., 1974, Ultraviolet carcinogenesis: Experimental, global and genetic aspects, in: Sunlight and Man (M. A. Pathak, L. C. Harber, M. Seiji, and A. Kukita, eds.), pp. 259–283, University of Tokyo Press, Tokyo.Google Scholar
  212. Uretz, R. B., 1955, Additivity of X-rays and ultraviolet light in the inactivation of haploid and diploid yeast, Radiat. Res. 2:240–252.Google Scholar
  213. Van der Leun, J. C., and Stoop, T. H., 1969, Photorecovery of ultraviolet erythema, in: The Biologic Effects of Ultraviolet Radiation (F. Urbach, ed.), pp. 251–254, Pergamon Press, Oxford.Google Scholar
  214. Varghese, A. J., 1972, Photochemistry of nucleic acids and their constituents, in: Photophysiology, Vol. 7 (A. C. Giese, ed.), pp. 207–274, Academic Press, New York.Google Scholar
  215. Weatherwax, R. S., 1956, Desensitization of E. coli to UV light,J. Bacteriol. 72:124–125.Google Scholar
  216. Webb, R. B., 1977, Lethal and mutagenic effects of near-ultraviolet radiation, in: Photochemical and Photobiological Reviews, Vol. 2 (K. C. Smith, ed.), pp. 169–261, Plenum Press, New York.Google Scholar
  217. Westra, A., 1971, The influence of radiation on the capacity of in vitro cultured cells to proliferate, Ph.D. thesis, University of Amsterdam.Google Scholar
  218. Westra, A., and Dewey, W. C., 1971, Variation in sensitivity to heat shock during the cell-cycle of Chinese hamster cells in vitro, Int. J. Radiat. Biol. 19:467–477.Google Scholar
  219. Wheatcroft, R., Cox, B. S., and Haynes, R. H., 1975, Repair of UV-induced damage and survival in yeast. 1. Dimer excision, Mutat. Res. 30:209–218.Google Scholar
  220. Willis, I., Kligman, A., and Epstein, J. H., 1973, Effects of long ultraviolet rays on human skin: Photoprotective or photoaugmentative, J. Invest. Dermatol. 59:416–420.Google Scholar
  221. Witherspoon, J. P., and Corney, A. K., 1970, Differential and combined effects of beta, gamma and fast neutron irradiation of Soybean seedlings, Radiat. Bot. 10:429–435.Google Scholar
  222. Withrow, R. B., and Moh, C. C., 1957, Non-ionizing radiant energy as an agent in altering the incidence of X-ray induced chromatid aberrations. 1. Effects of far-red and infrared radiant energy on Tradescantia and Vicia, Radiat. Res. 6:491–500.Google Scholar
  223. Witkin, E. M., 1969, Ultraviolet-induced mutation and DNA repair, Annu. Rev. Microbiol. 23:487–514.Google Scholar
  224. Witkin, E. M., 1975, Relationships among repair, mutagenesis and survival: Overview, in: Molecular Mechanisms for Repair of DNA, Part A (P. C. Hannawalt and R. B. Setlow, eds.), pp. 347–355, Plenum Press, New York.Google Scholar
  225. Witkin, E. M., 1976, Ultraviolet mutagenesis and inducible DNA repair in Escherichia coli, Bacteriol Rev. 40:869–907.Google Scholar
  226. Woeber, K., 1965, The effects of ultrasound in the treatment of cancer, in: Ultrasonic Energy (E. Kelly, ed.), pp. 137–149, University of Chicago Press.Google Scholar
  227. Wolff, S., 1968, Chromosome aberrations and the cell cycle, Radiat. Res. 33:609–619.Google Scholar
  228. Wolff, S., and Luippold, H. E., 1965, Mitotic delay and the apparent synergism of far-red radiation and X-rays in the production of chromosomal aberrations, Photochem. Photobiol. 4:439–445.Google Scholar
  229. Woodcock, E., and Grigg, G. W., 1972, Repair of thermally induced DNA breakage in E. coli, Nature (New Biol.) 237:76–79.Google Scholar
  230. Yan, Y., and Kondo, S., 1964, Synergistic effects of P-32 decay and ultraviolet irradiation on inactivation of Salmonella, Radiat. Res. 22:440–456.Google Scholar
  231. Ying, C. Y., Parnsh, J. A., and Pathak, M. A., 1974, Additive erythemogenic effects of middle (280–320 nm) and long (320–400 nm) wave ultraviolet light, J. Invest. Dermatol. 63:273–278.Google Scholar
  232. Yost, H. T., 1951, The frequency of X-ray induced chromosome aberrations in Tradescantia as modified by near-infrared radiation, Genetics 36:176–184.Google Scholar
  233. Youngs, D. A., and Smith, K. C., 1976, Genetic control of multiple pathways of post-replicational repair in uvrB strains of Escherichia coli K-12, J. Bacteriol. 125:102–110.Google Scholar

Copyright information

© Plenum Press, New York 1978

Authors and Affiliations

  • Rex M. Tyrrell
    • 1
  1. 1.Instituto de BiofísicaUniversidade Federal do Rio de JaneiroR.J.Brazil

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