Abstract：
:We present measurements of low-energy (<18 eV) electron-stimulated desorption of anions from acetamide (CH(3)CONH(2)) and dimethyl disulfide [DMDS: (CH(3)S)(2)] films. Electron irradiation of physisorbed CH(3)CONH(2) produces H(-), CH(3)(-) and O(-) anions, whereas the H(-), CH(2)(-), CH(3)(-), S(-), SH(-) and SCH(3)(-) anions are observed to desorb from the DMDS film. Below 12 eV, the dependence of the anion yields on the incident electron energy exhibits structures that indicate that a resonant process (i.e. dissociative electron attachment) is responsible for molecular fragmentation. Within the range of 1-18 eV, it is found that (1.7 and 1.4) x 10(7) H(-) ions/incident electron and (7.8 x 10(-11) and 4.3 x 10(-8)) of the other ions/incident electron are desorbed from acetamide and DMDS films, respectively. These results suggest that, within proteins, the disulfide bond is more sensitive to low-energy electron attack than the peptide bond. In biological cells, some proteins interact closely with nucleic acid. Therefore, the observed fragments, when produced from secondary low-energy electrons generated by high-energy radiation, not only may denature proteins, but may also induce reactions with the nearby nucleic acid and damage DNA.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Abdoul-Carime H,Cecchini S,Sanche Ldoi
10.1667/0033-7587(2002)158[0023:aopsib]2.0.co;2subject
Has Abstractpub_date
2002-07-01 00:00:00pages
23-31issue
1eissn
0033-7587issn
1938-5404journal_volume
158pub_type
杂志文章abstract：:The reactions of free and DNA-bound 2,2,5,5-tetramethylpyrrolidine-N-oxyl (PROXYL) probes with radicals generated during radiolysis of dilute aqueous solutions of DNA were examined. For the free PROXYL probe in deaerated solution with each of the four nucleotides (dAMP, dCMP, dGMP, and TMP) it was found that the pyrim...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：:Radiation-induced apoptosis in lymphocyte-derived cell lines is characterized by endonucleolytic cleavage of cellular DNA within hours after radiation exposure. We have studied this phenomenon qualitatively (DNA gel electrophoresis) and quantitatively (diphenylamine reagent assay) in murine EL4 T-lymphoma cells expose...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-03-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1998-09-01 00:00:00
abstract：:The molecular basis of radiotherapy-related multidrug resistance (MDR) is still unclear. Here we report on a study investigating the effect of fractionated irradiation on expression of the MDR-associated proteins P-glycoprotein (P-gp), multidrug resistance-associated protein (MRP), and lung resistance-related protein ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR0986.1
更新日期：2008-07-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1996-03-01 00:00:00
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journal_title：Radiation research
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更新日期：2017-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-05-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/r3016
更新日期：2003-07-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1998-06-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-11-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-10-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2001)155[0235:pcdtma]2.0.co;2
更新日期：2001-01-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-08-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-12-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-07-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-04-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1952.1
更新日期：2010-05-01 00:00:00
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journal_title：Radiation research
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更新日期：2009-11-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章,评审
doi：
更新日期：1996-05-01 00:00:00
abstract：:The non-human primate has been a useful model for studies of human acute radiation syndrome (ARS). However, to date structural changes in various parts of the intestine after total body irradiation (TBI) have not been systematically studied in this model. Here we report on our current study of TBI-induced intestinal s...
journal_title：Radiation research
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更新日期：2015-11-01 00:00:00
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doi：10.1667/0033-7587(2001)156[0028:ammfct]2.0.co;2
更新日期：2001-07-01 00:00:00
abstract：:Vascular injury after radiation exposure contributes to multiple types of tissue injury through a cascade of events. Some of the earliest consequences of radiation damage include increased vascular permeability and promotion of inflammation, which is partially manifested by increased leukocyte-endothelial (L/E) intera...
journal_title：Radiation research
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更新日期：2018-07-01 00:00:00
abstract：:In light-ion radiation therapy, both the dose and the local energy spectrum, which is often characterized with the linear energy transfer (LET), must be considered. In treatment optimization, it is advantageous to use a radiobiological model that analytically accounts for both dose and LET for the ion type of interest...
journal_title：Radiation research
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doi：10.1667/RR2045.1
更新日期：2010-10-01 00:00:00
abstract：:The lactose operon functions under the control of the repressor-operator system. Binding of the repressor to the operator prevents the expression of the structural genes. This interaction can be destroyed by the binding of an inducer to the repressor. If ionizing radiations damage the partners, a dramatic dysfunction ...
journal_title：Radiation research
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更新日期：2005-04-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-06-01 00:00:00
abstract：:To study the acquired radioresistance of tumor cells, a model system of two cell lines, Djungarian hamster fibroblasts (DH-TK-) and their radioresistant progeny, was established. The progeny of irradiated cells were isolated by treating the parental cell monolayer with a single dose of 20 Gy (PIC-20). The genetic and ...
journal_title：Radiation research
pub_type： 杂志文章
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更新日期：2005-12-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
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journal_title：Radiation research
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doi：
更新日期：1985-12-01 00:00:00
abstract：:Accurate assessment of risks of long-term space missions is critical for human space exploration. It is essential to have a detailed understanding of the biological effects on humans living and working in deep space. Ionizing radiation from galactic cosmic rays (GCR) is a major health risk factor for astronauts on ext...
journal_title：Radiation research
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更新日期：2018-06-01 00:00:00
