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AbstractAbstract
[en] With the biomedical pion channel of the 590 MeV proton-accelerator of the Swiss Institute for Nuclear Research (SIN) for to test some theoretical conceptions in comparison to several preliminary experiments performed with pions of low dose rate. The dosimetric measurements showed an excellent depth curve with, e.g., a peak/plateau ratio of 2.5, for the momentum of 180 MeV/c and a ratio e-/π- of 0.1. The following systems have been used: Inactivation of single mammalian cells, induction of chromatid aberrations in Chinese hamster cells; small intestine of mouse (early and late effects); early and late effects in the mouse foot; induction of anomalies in mouse embryos; induction of cerebral microvascular damage in neonate rats; proliferation of Ehrlich-ascites carcinoma cells; induction of different types of mutation in different stages of male germ cells and somatic cells (Drosophila). The RBE-values in the peak region vary between 0,7-3.3, and are different even within the same system with the same end point but at different cell stages and conditions. For the plateau region the RBE-values lie mostly under 1 (compared with 140 kV-photons) and can be identical with 29 MeV-photons. The clinically important peak/plateau relation lies over 1 in every experiment and reaches even the value of 4.2. The unexpected RBE-values in peak under 1 lead to a new conception of RBE, the two system theory. In intrinsically radiosensitive euoxic systems (healthy tissue) the RBE of peak (star) pions can be under 1, in intrinsically radioresistant hypoxic systems (tumor cells) over 1. The two systems can also have different vulnerabilities of these repair systems. (orig./MG) 891 MG/orig.- 892 CKA
[de]
Am biomedizinischen Pionenkanal des 590 MeV Protonbeschleunigers des Schweizerischen Instituts fuer Nukleare Forschung (SIN) werden seit einigen Jahren theoretische Konzepte ueber Pionen mit geringer Dosisleistung ueberprueft. Die dosimetrischen Messungen zeigten bei einem Impuls von 180 MeV/c und einem e-/π- Verhaeltnis von 0,1 eine ausgezeichnete Tiefenkurve mit z.B. einem Peak/Plateauverhaeltnis von 2,5. Folgende Systeme werden verwendet: Inaktivierung vereinzelter Saeugerzellen; Induktion von Chromatidenaberrationen in Zellen von chinesischen Hamstern; Maeuseduenndarm (Frueh- und Spaetfolgen); Frueh- und Spaetfolgen in Maeusepfoten; Induktion von Anomalien bei Maeuseembryos; Induktion von zerebralen mikrovaskularen Schaeden bei neugeborenen Ratten; Proliferation von Ehrlich-Asziteskarzinomzellen; Induktion verschiedener Mutationen in verschiedenen Stadien von maennlichen Keimzellen und somatischen Zellen (Drosophila). Die RBE-Werte im Peak-Bereich liegen zwischen 0,7 und 3,3; sie sind sogar innerhalb des gleichen Systems unterschiedlich, mit gleichen Endpunkten in verschiedenen Zellstadien und -bedingungen. Die RBE-Werte fuer den Plateaubereich liegen meist unter 1 (im Vergleich zu 140 kV Photonen) und koennen mit 29 MeV Photonen identisch sein. Die klinisch bedeutsame Peak/Plateau-Beziehung liegt stets ueber 1 (sogar bis zu 4,2). Zwei unerwartete RBE-Werte mit Peak unter 1 fuehren zu einer neuen RBE-Konzeption, der Zwei-System-Theorie. Bei intrinsisch strahlungsempfindlichen enoxischen Systemen (gesundes Gewebe) kann der RBE von Peak(Stern-) Pionen unter 1 liegen, bei identisch strahlungsunempfindlichen hypoxischen Systemen (Tumorzellen) ueber 1. Ausserdem ist bei beiden Systemen die Empfindlichkeit des Reparatursystems unterschiedlich. (orig./MG)Primary Subject
Secondary Subject
Source
14. annual meeting of the European Society of Radiation Biology; Juelich, Germany, F.R; 9 - 13 Oct 1978
Record Type
Journal Article
Literature Type
Conference; Numerical Data
Journal
Radiation and Environmental Biophysics; ISSN 0301-634X;
; v. 17(1); p. 47-65

Country of publication
ANIMAL CELLS, ANIMALS, CHROMOSOMAL ABERRATIONS, DELAYED RADIATION EFFECTS, EARLY RADIATION EFFECTS, EXPERIMENTAL DATA, FETUSES, GENETIC RADIATION EFFECTS, MALFORMATIONS, MUTAGENESIS, NUMERICAL DATA, OXYGEN ENHANCEMENT RATIO, PION BEAMS, PIONS MINUS, RADIOBIOLOGY, RBE, SURVIVAL CURVES, TABLES, TUMOR CELLS
ANTIMATTER, ANTIMESONS, ANTIPARTICLES, BEAMS, BIOLOGICAL EFFECTS, BIOLOGICAL RADIATION EFFECTS, BIOLOGY, BOSONS, DATA, DATA FORMS, DISEASES, ELEMENTARY PARTICLES, GENETIC EFFECTS, HADRONS, INFORMATION, MATTER, MESON BEAMS, MESONS, MUTATIONS, PARTICLE BEAMS, PATHOLOGICAL CHANGES, PIONS, PSEUDOSCALAR ANTIMESONS, PSEUDOSCALAR MESONS, RADIATION EFFECTS
Reference NumberReference Number
INIS VolumeINIS Volume
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AbstractAbstract
No abstract available
Original Title
Ein mathematisches Modell fuer die Beschreibung von Kinetik und Zeitfaktor der strahleninduzierten Mitosehemmung
Primary Subject
Source
51. German Roentgen congress; Munich, F.R. Germany; 21 May 1970; 3 figs.; 4 refs. Short communication only.
Record Type
Journal Article
Literature Type
Conference
Journal
Fortschritte auf dem Gebiete der Roentgenstrahlen und der Nuklearmedizin; p. 21-23
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
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AbstractAbstract
No abstract available
Primary Subject
Secondary Subject
Source
International Atomic Energy Agency, Vienna (Austria); Proceedings series; p. 369-381; 1971; IAEA; Vienna; Symposium on biophysical aspects of radiation quality; Lucas Heights, Australia; 8 Mar 1971; IAEA-SM--145/12
Record Type
Book
Literature Type
Conference
Country of publication
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INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] The textbook is written with special regard to radiation protection of man. It shall enable the reader to assess the potential radiation risks to living organisms and lead him to an insight into radiation protection measures. The following topics are covered: physical fundamentals of ionizing radiations; physical and chemical fundamentals of biological radiation effects; radiation effects on cells, organs, organ systems, and whole animal organisms focussing on mammals and man; modification of radiation effects; chemical radiation protection; therapy of radiation injuries; radionuclide kinetics; biological radiation effects in connection with radiation hazards and with the limitation of radiation exposure. It is intended for vocational education of medical personnel
Original Title
Einfuehrung in die Strahlenbiologie
Primary Subject
Source
1977; 116 p; VEB Verlag Volk und Gesundheit; Berlin
Record Type
Book
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
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AbstractAbstract
[en] It is argued that proliferating normal tissues fall into two categories. In type H (for hierarchical) tissues, cells either multiply or perform tissue-specific functions. Sterilizing does of radiation immediately initiate a gradual depopulation of irreversibly postmitotic, mature cells. The constant rate of functional cell depletion is given by physiological longevity of the cells. Consequently the onset of maximal depopulation is dose-in-dependent and, after a range of radiation doses, the peak of milder damage is seen earlier than that of a more severe one. In type F (for flexible) tissues all cells are assumed to have the potential for proliferation and are also engaged in tissue-specific functions. Radiation leads to dose-dependent loss of the functional cells through their mitotic death, both immediately after exposure and during the next phase of increased compensatory proliferation resulting in accelerated expression of radiation damage. Consequently the more severe damage following larger doses of radiation is seen earlier than the milder one produced with smaller doses. Assays of cell clonogenicity in vivo concern almost exclusively type H pupulations. The large radiation/drug/heat doses administered in these assays serve both to dilute the clonogenic cells by at least two orders of magnitude, and to produce a measurable response. When comparing two agents or interpreting their combined action it is advisable to ensure that the dilution step yields qualitatively comparable samples of clonogenic cells to be then characterized in terms of dose-survival curve parameters. (orig.)
[de]
Es wird angenommen, dass proliferierende normale Gewebe zwei verschiedenen Kategorien angehoeren. Bei Geweben des Typs H (hierarchische Gewebe) vermehren sich die Zellen entweder, oder sie erfuellen gewebespezifische Funktionen. Sterilisierende Strahlendosen bewirken daher sofort ein allmaehliches Abnehmen irreversibel postmitotischer, reifer Zellen. Die konstante Verringerung funktionaler Zellen ist auf die physioligische Langlebigkeit der Zellen zurueckzufuehren. Der Beginn der maximalen Depopulation ist somit dosisunabhaengig, und nach einer Reihe von Bestrahlungen ist das Maximum fuer leichtere Schaeden eher sichtbar als fuer schwere Schaeden. Bei Geweben des Typs F (flexible Gewebe) besitzen alle Zellen die Faehigkeit zur Proliferation und erfuellen gleichzeitig gewebespezifische Funktionen. Die Bestrahlung bewirkt einen dosisabhaengigen Verlust an funktionalen Zellen durch mitotischen Zelltod, und zwar direkt nach der Bestrahlung und in der darauf folgenden Phase erhoehter kompensatorischer Proliferation, die zu einer beschleunigten Expression des Strahlenschadens fuehrt. Infolgedessen it der staerkere Schaden nach hoeheren Strahlendosen eher sichtbar als der schwaechere Schaden nach niedrigen Dosen. Assays der Zellclonogenizitaet in vivo befassen sich fast ausschliesslich mit H-Populationen. Die dabei verabreichten hohen Dosen von Strahlung/Arzneimitteln/Waerme verduennen die clonogenen Zellen um mindestens zwei Groessenordnungen und bewirken eine messbare Antwort. Beim Vergleich von zwei Medikamenten und der Interpretation ihrer kombinierten Wirkung sollte man darauf achten, dass bei der Verduennung qualitativ vergleichbare Proben clonogener Zellen erzeugt werden, die dann als Dosis/Ueberlebenskurven charakterisiert werden koennen. (orig.)Primary Subject
Record Type
Journal Article
Journal
Radiation and Environmental Biophysics; ISSN 0301-634X;
; v. 19(3); p. 157-172

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] The time-dependent radioecological model to Korean environment has been developed in order to assess the radiological consequences following the short-term deposition of radionuclides in an accident of nuclear power plant. Time-dependent radioactivity concentrations in foodstuffs can be estimated by the model called 'KORFOOD' as well as time-dependent and time-integrated ingestion doses. Three kinds of critical radionuclides and thirteen kinds of foodstuffs were considered in this model. Dynamic variation of radioactivities were simulated by considering several effects such as deposition, weathering and washout, resuspension, root uptake, translocation, leaching, senescence, intake and excretion of soil by animals, intake and excretion of feedstuffs by animals, etc. The input data to the KORFOOD are the time of the year when the deposition occurs, the kinds of radionuclides and foodstuffs for estimation. The time-dependent specific activities in rice and the ingestion doses due to the consumption of all considered foodstuffs were calculate with deposition time using agricultural data-base in Kori region. In order to validate of KORFOOD, the calculated results were compared with those by a leading German model, ECOSYS-87. The comparison of results shows good agreements within a factor of ten. (Author)
Primary Subject
Record Type
Journal Article
Journal
Journal of the Korean Association for Radiation Protection; ISSN 0253-4231;
; CODEN BBHCDU; v. 18(1); p. 9-23

Country of publication
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Kottbauer, M. M.
Technische Univ. Wien, Wien (Austria)1997
Technische Univ. Wien, Wien (Austria)1997
AbstractAbstract
[en] In this work two biological based models were developed. First the single-hit model for solid tumors (SHM-S) and second the single-hit model for leukemia (SHM-L). These models are a further development of the Armitage-Doll model for the special case of a short time radiation exposure. The basis of the models is the multistage process of carcinogeneses. The single-hit models provide simultaneously the age-dependent cancer-rate of spontaneous and radiation induced tumors as well as the dose-effect relationships at any age after exposure. The SHM-S leads to a biological based dose-effect relationship, which is similar to the relative risk model suggested by the ICRP 60. The SHM-S describes the increased mortality rate of the bomb survivors more accurate than the relative risk model. The SHM-L results in an additive dose-effect relationship. It is shown that only small differences in the derivation of the two models lead to the two dose-effect relationships. Beside the radiation exposure the new models consider the decrease of the cancer mortality rate at higher ages (age>75) which can be traced back mainly to three causes: competitive causes of death, reduction of cell proliferation and reduction of risk groups. The single-hit models also consider children cancer, the different rates of incidence and mortality, influence of the immune system and the cell-killing effect. (author)
Original Title
Mechanistische modelle fuer die Krebsentstehung nach akuter Strahlenexposition
Primary Subject
Source
Dec 1997; 269 p; Available from Technische Univ. Wien Bibliothek, Wiedner Hauptstrasse 6-8, 1040 Vienna (AT); Reference number: 570249II; Thesis (Dr. techn.)
Record Type
Miscellaneous
Literature Type
Thesis/Dissertation
Country of publication
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AbstractAbstract
[en] Visibility of changes, accessibility for sampling and measuring and extensive past study, make skin the premier model for the assessment of dose-time fractionation relationships. The primary pathophysiologic basis of radiation-induced reactions in the skin is disruption of the reproductive activity of the basal cells. Radiation reactions in the skin increase in proportion to: (a) increased absorption of energy related to the quality of radiation used; (b) increased area irradiated; (c) increased total dose, and (d) decreased overall period of treatment. Radiation-induced reactions may decrease per unit dose with very low dose rates (i.e. 100 cGy/h) and very high dose rates (i.e. 10 Gy/s). Radiation-induced reactions may decrease per unit dose with prolongation of the individual treatment or overall time of the series of treatments. The proportionality between early and late reactions can be altered by various factors such as dose increment size or the quality of the radiations. The most dangerous changes clinically reduce the intensity of the acute reaction in proportion to the late injury
Primary Subject
Secondary Subject
Source
Vaeth, J.M.; Meyer, J; p. 53-61; 1988; p. 53-61; S. Karger Publishers Inc; New York, NY (USA); 22. annual San Francisco cancer symposium on time, dose, and fractionation in the radiation therapy of cancer: a frontier revisited; San Francisco, CA (USA); 7-8 Mar 1987
Record Type
Book
Literature Type
Conference
Country of publication
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AbstractAbstract
[en] The ability of modern radiotherapy equipment to deliver complex and highly tailored radiation treatments has until recently far exceeded the ability of computerized radiotherapy treatment planning (RTP) systems to simulate such treatments. While considerable effort has been devoted to improving the dose calculation methods, far less attention has been given to the problem of how a dosimetrist, physicist, or physician can most effectively utilize the power of three-dimensional treatment geometry. In this article the authors discuss this 'user-interface' problem and describe some efforts at solutions that utilize ideas and methods from the computer industry outside radiotherapy applications
Primary Subject
Source
Vaeth, J.M.; Meyer, J; p. 33-43; 1987; p. 33-43; S. Karger Publishers Inc; New York, NY (USA); 21. annual San Francisco cancer symposium; San Francisco, CA (USA); 28 Feb - 1 Mar 1986
Record Type
Book
Literature Type
Conference
Country of publication
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AbstractAbstract
[en] On the basis of literary data biological effect of low dose irradiation on organism is analysed. Effect of natural background on development of living organisms, stimulating and carcinogenic effect of low dose irradiation are discussed. Discussion data on possible threshold radiation effect, as well as investigations in determining death hazard because of neoplasms in a-bomb survivors of Hirosima and Nagasaki are presented. Possibility of developing dose-effect relationships mathematical models is discussed
Original Title
Novoe v izuchenii ehffekta malykh doz ioniziruyushchej radiatsii
Primary Subject
Secondary Subject
Source
Nauchno-Issledovatel'skij Inst. Radiatsionnoj Gigieny, Leningrad (USSR); p. 50-59; 1987; p. 50-59; 31 refs.
Record Type
Miscellaneous
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