最新刊期
期 4 ， 1995
- 摘要：A summary of polymerization methods, mechanism, kinetics and so on of acrylonitrile induced by radiation have been completed according to the investigation results.关键词：Acrylonitrile;Radiation polymerization;Polymerization method;Polymerization mechanism;Polymerization kinetics
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发布时间：2023-04-23 - 摘要：Surface blistering of the amorphous alloys Co70.2Fe3.9Nb3.9Si14B8 and Co66Fe4.5V2.25Ni2.25Si10B15 due to argon ion bombardment at energies of 150, 195 and 300 keV has been observed with a scanning electron microscope (SEM). The critical dose for onset of blistering and the blister diameter are determined and found to increase with increasing projectile energy. Above about 195 keV, blisters and rupture of blisters are the predominant surface damage phenomena. However, at 150 keV, there is no evidence of cracked blisters. The effects are interpreted in terms of argon agglomeration, building-up of the critical argon pressure, and argon releasing from near-surface regions.关键词：Argon ion irradiation;Amorphous alloy;Blistering
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发布时间：2023-04-23 - 摘要：The effect of minor additive Si or Ti, as well as both Si and Ti on behavior of radiation swelling for 316 stainless steel alloy (316 SS), irradiated at 550℃, using high voltage electron microscope (HVEM) with 1MeV electron beam was studied, and the swelling morphology was observed in situ under HVEM. Silicon (1 wt%), as well as Ti (0.1 wt%) can inhibit radiation swelling when the dose is not more than 11dpa. The 316 SS bearing 1 wt% Si additive has even larger swelling rate than that of the alloy without any additive, when dose is more than 13 dpa. 0.5 wt% Ti additive can even completely prevent it from swelling under the dose up to 33 dpa, but there are some small Ti compound particles segregated on radiation area. Experimental results show that the synergistic effect of both Si and Ti can completely prevent 316 alloys from swelling under radiation dose up to 33 dpa, but there are also a little Ti compound particles segregated on the circle of central area, but the number and size of the particles increase slightly with the dose.关键词：Radiation swelling;Alloy additive;Electron radiation;316 stainless steel;Si;Ti
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发布时间：2023-04-23 - 摘要：Molar absorptivity is a very important experimental parameter in dosimetry for radiation processing, It is involved many important aqueous chemical systems such as Fricke, ceric-cerous and dichromate. Because of differences of instrument type, analytical determination procedures and methods and many other factors, the results that researchers have obtained are different. Some problems on the determination of molar absorptivity are discussed.关键词：Dosimetry for radiation processing;Molar absorptivity;Determination;Aqueous chemical system
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发布时间：2023-04-23 - 摘要：Radiosensitizing effect of sodium glycididazole (SGDD) on the hypoxic V79 cells by standard in vitro colon formation method has been further studied. The results showed its toxicity was low. Its ID50 in cells under hypoxic and aerobic condition were 23.5 and 35.7 mmol/L respectively. These indicated that SGDD showed more toxicity under hypoxic than that aerobic condition (p<0.01). SGDD did not produce any radiosensitizing effect under air condition, however, irradiation under hypoxic SGDD showed radiosensitization and its SER increased as a function of drug concentration below 1.38 mmol/L. Its C1.6 was 0.48 mmol/L. Its maxium SER was 2.3 at 1.38 mmol/L. Comparison of radiosensitizing effect of SGDD versus MISO and its mother compound (metronidazole) under the same experimental condition, SER for SGDD, MISO and metronidazole were 1.75, 1.53 and 1.07 at 0.3 mmol/L respectively. SGDD showed more radiosensitizing efficiency than MISO and much greater than metronidazole. This study further confirms our previous results i.e. SGDD is a hypoxic radiosensi tizer with low toxic, high efficiency and selectively enhances the radiosensitivity of hypoxic cells for tumor radiotherapy.关键词：Sodium glycididazole;V79 cells;ID50;OER;SER
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发布时间：2023-04-23 - 摘要：Ataxia-telangiectasia (AT) is a rare human autosomal recessive disease characterized by hypersensitivity to ionizing radiation, neurological disorders, immunodeficiency, chromosomal instability and a high incidence of cancers. It was thought that the cause for hypersensitivity was due to the putative DNA repair gene deficiency. Recently, studies on genetic linkage analysis of families with AT carriers had suggested that a genetic defect in a region of chromosome 11 q 22~23 was responsible for the AT disorder. The SV 40-transformed AT5BIVA cells (group D), from skin fibroblast of AT patients, was hypersensitive to Gamma-ray. The karyotype analysis had previously shown there were abnormalities of chromosome 11, 13,14,15 and 22 in AT5BIVA cells. In order to study the molecular mechanism of hyper-radiosensitivity in AT cells and to map DNA repair gene, a new strategy to introduce intact chromosomes into AT 5 BIVA cells by the technique of microcell-mediated chromosome transfer (MMCT) was used.Two human×mouse hybrid cells (FD 3 and FD 8) and a mouse cell line (LM/TK-) were used. FD 3 cells contain human chromosome 11 while FD 8 does not, The microcells of these three cell lines were prepared and fused with AT 5 BIVA cells. After twice selection by 3 Gy γ- irradiation, the clones which were resistant to γ-irradiation were isolated. AT/FD 3-1 cells, the AT 5 BIVA×FD 3 mircocell fused hybrid, showed enhancement of radioresistance. Karyotype analysis had also shown AT/FD 3-1 cells contained an additional copy of chromosome 11. The results indicated the genes responsible for cell resistance to ionizing irradiation existed in human chromosome 11.关键词：Ionizing radiation;AT cells;Human chromosome 11;Microcell mediated chromosome transfer
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发布时间：2023-04-23 - 摘要：By using the techniques of culture of mice thymus stromal cells in vitro, the characteristics of thymus stromal cells, their dynamic changes in various times in normal and after irradiation, their radiosensitivity was studied. The values of D0 and n of thymus stromal cells were 2.3 Gy and 1.4 respectively. Decreases in number of stromal cells after irradiation with doses of 0.75 Gy and 1.5 Gy was not significant compared with group of non-irradiation. Significant decreases in number of stromal cells occured by irradiation with doses of 4.0 Gy and 8.0 Gy.关键词：Thymus stromal cells;Radiosensitivity;Macroenvironment;Organ culture
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发布时间：2023-04-23 - 摘要：Synaptonemal complexes revealed mutagen-induced effects in germ cell meiotic chromosomes. Male mice were irradiated by 4 Gy X-rays and spermatocytes were harvested at different time after exposure. Various form of synaptonemal complex aberrations were observed, such as breaks, rings, rearrangement which were consistent with those aberrations observed in metaphase I chromosome by conventional cytogenetic analysis. Some novel forms of synaptonemal complex aberrations were observed. The relationship between synaptonemal complex aberration and chromosome aberration was discussed.关键词：Ionizing radiation;Synaptonemal complex;Chromosome;Aberration
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发布时间：2023-04-23 - 摘要：Our previous investigtion revealed a restorative effect of exogenous nucleic acids on the intestinal crypt in mice after abdominal γ-irradiation. In this article, the factors influencing the restorative effect of exogenous RNA on the intestinal crypt in mice post-irradiation were studied. The results showed that: (a)RNAs from different sources all showed the crypt survival enhancement capability.(b) Bell-shaped curves correlating the crypt survival fraction and RNA doses were obtained, with the optimal doses for different routes of administration estimated.(c) Comparing the different routes of RNA administration, the intravenous injection seemed to be the most effective. (d) An exponential relationship between the crypt survival fraction and the post-irradiation time of RNA administration was found. The earlier the administration, the more effective it was. (e) Administration of RNA merely once within 6 h after irradiation, the increases of crypt survival fraction was statistically significant when compared with that of the irradiated control.关键词：Exogenous RNA;Ionizing radiation;Intestinal crypt survival;Radiation injury
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发布时间：2023-04-23 - 摘要：Adault male mice were irradiated with γ-rays 6 Gy once or 3 Gy three times in 7 days and intraperitoneally injected with colony-stimulating factor(CSF) in high doses or low doses. Mice of the control group were injected with normal saline only. Within 30 days after irradiation, the survival rate of mice irradiated with 6 Gy γ-rays once and treated with high dose CSF was 9/25, while that in the control group was 2/25. The survival rate of mice irradiated with 3 Gy three times and treated with high dose CSF was 10/13, while that in the control group was 4/13. Moreover, the survival times of both irradiated groups treated with high dose CSF were much longer than the control groups (p<0.01). This experiment also showed that CSF could reduce the lowering of peripheral blood white blood cell counts and promote their recovery. The number of CFU-S in mice treated with CSF was much higher (23.8±4.82) than in the control group (9.4± 4.39) (p<0.01). Therefore, CSF could recover and reconstruct the hematopoietic function of bone marrow, and prolong the survival of irradiated mice.关键词：Colony-stimulating factor;CFU-S;Radiation
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发布时间：2023-04-23 - 摘要：Human skin fibroblasts were irradiated with 60Co γ-ray 10 Gy~40 Gy. After one hour, the concentration of
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发布时间：2023-04-23 - 摘要：The effects of PGS injection before total body X-irradiation on free radicals changes in spleen of mice were studied by means of ESR technique. The results showed that the contents of free radicals in spleen of mice injected with PSG before irradiation were lower than those of irradiation control group at 3Gy. Different concentration of PSG(125~500 mg/kg•d) could markedly decrease the contents of free radicals in irradiation group with 3Gy. While, free radicals in group with PSG 6 h, after irradiation were significantly lower than those irradiation control group. The results indicated that PSG could decrease free radicals in 3Gy X-rays irradiated mice especially for 3 hours after irradiation.关键词：X-radiation;Polysaccharides of Ginseng;Free radicals
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发布时间：2023-04-23 - 摘要：ABCTRACT The electron spin resonance (E. S. R) spectra of γ-irradiated DNA, chinonin and their mixture (the nucleotide and chinonin in mol ratio of 1:1) were investigated at normal temparature. Based on g value, the shape and width and signal amplitude of ESR spectra, We may concluded that the electron spin may transfer from DNA to chinonin with a transfer ratio of 5.63.关键词：Chinonin;DNA;Electron spin transfer;ESR
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发布时间：2023-04-23
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