最新刊期
期 5 ， 2008
- 摘要：It has been proved that the antimalarial agent, Artemisinin and its derivates (such as artemether, arteether, artesunate, dihydroartemisinine, etc) boast powerful antitumor effects. Recently, researches have found that Artemisinin and its derivates can also enhance the radio-sensitivity of tumors through regulating cell cycle, creating cytotoxic effects induced by ROS, suppressing GSH activity and inhibiting the reparation of DNA damage etc. Moreover, they can reduce cell survival in a dose-dependent manner. This paper is paying more attention on the radio-sensitizing effects, characteristics and mechanisms of artemisinin and its derivates.关键词：Artemisinin and its derivates;Antitumor;Radio-sensitization;Radio-sensitizing mechanisms
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发布时间：2023-03-30 - 摘要：The study on bio-electromagnetics can be traced back to as early as 1789, The understanding of its nature and application has been increasing with technological development studies at home and abroad. It has been suggested that electromagnetic radiation can induce different injury to human organs including central nervous system, incretion, cardiovascular system, procreation, hematopoietic system, immunity, vision and so on. However, the studied results obtained by scientists with different method and bio-model show very complex and some show inconsistent. This paper is to summarize the studies of effects on various organs by microwave.关键词：Electromagnetic radiation;Organism;Radiation effects
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发布时间：2023-03-30 - 摘要：Sweet sorghum (Sorghum bicolor (L) Moench) seeds were implantated by carbon ion for different dose (0Gy, 10Gy, 30Gy, 50Gy, 80Gy) respectively, then plant height, biomass, contents of chlorophyll, malondialdehyde (MDA) and soluble sugar of M2 seedlings were measured in order to investigate the response of M2 seedlings to heat stress. The results show that plant height and chlorophyll content are changed unobviously among all treatments. Biomasses of M2 seedlings are higher after low dose (10Gy, 30Gy) of carbon ion implantation than that of high dose (50Gy, 80Gy) treatment, while the treatment of carbon ion implantation for 30Gy enhances the heat tolerance of M2 seedlings by decreasing the content of MDA and soluble sugar.关键词：Carbon ion;Sugar sorghum;Heat stress
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发布时间：2023-03-30 - 摘要：In this paper, the simulations of dose distribution of reactor for technology of flue gas desulfurization and denitrification by irradiation of electron beam are carried out using EGSnrcMP Monte-Carlo program. The simulated results are carefully analyzed by utilizing MATLAB. It is shown that a good agreement is reached by comparing the calculated results with experiment data from the literatures. Thus EGSnrcMP program will be a powerful simulation tools to the design and appraisement for dealing with the similar problem.关键词：Electron beam;Monte Carlo method;EGSnrcMP system;Dose distribution;Flue gas desulphurization and denitrification
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发布时间：2023-03-30 - 摘要：Radiation effect of γ-rays on lignin was studied. The lignin irradiated by γ-rays was characterized by GPC, IR and 13C-NMR respectively. It has been shown that cross-link reaction is the key reaction under this experimental condition, while the molecular weight and molecular weight distribution of lignin is increased. IR spectra of irradiated lignin are similar to that of former lignin. The functional groups of irradiated lignin almost have not change compared with former lignin. Hydroxyl groups in irradiated lignin are not only increased but also more stable. It has been found that the main functional groups in the molecular structure of alkali lignin are not destroyed after γ-rays irradiation according to the analysis with13C-NMR.关键词：γ-rays;Lignin;Radiation effect
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发布时间：2023-03-30 - 摘要：Four kinds of amines co-initiator with different structure were synthesized in Michael-Addition reaction with aliphatic amine and trimethylolprpane triacrylate (TMPTA). The photo-polymerization of tripropylene glycol diacrylate (TPGDA) / benzophenone (BP) / amine co-initiator was investigated by real-time infrared spectroscopy (RTIR). The yellowing of BP/amine co-initiator during UV curing was characterized by ultraviolet spectrophotometer. The results show that the increment of the content of hydroxyl group leads to the decrement of the photopolymerization rate. And the photo-polymerization rate decreases with the increment of molecular weight for the equal hydroxyl content. But there is no change with the double bond conversion. It has been demonstrated that the amines co-initiator with tertiary amine structure can cause higher yellowness index (YI) and faster yellowness index growth during UV irradiation than that with secondary amine structure. And the YI also increases with the increment of the content of hydroxyl group in the amines co-initiator. Lower yellowness index amines co-initiator could be synthesized based on the results obtained in this paper.关键词：Amine co-initiator;Real-time infrared spectroscopy (RTIR);Yellowness index;Ultraviolet spectro- photometer
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发布时间：2023-03-30 - 摘要：In this paper the mutation of lycopene producing strain, B.trispora(−) by use of low energy N+ ion implantation,was studied. Experimental results show that higher mutation rate and wider mutation spectrum have been obtained after B.trispora (−) being implanted and four lycopene high yielding strains B.trispora (−) BH3-701 et al have been screened out. It has been found that the average production of lycopene increases by 50% compared with that of original strain after five passages in shaking flasks. The highest yield strain BH3-701 can accumulate lycopene in the later stage and increase production efficiency greatly.关键词：N+ implantation;Mutation;Lycopene;Blakeslea trispora
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发布时间：2023-03-30 - 摘要：As polyester polyethylene composite membrane/ polyethylene is a new type of biological material suitable for clinical uses, the products were conducted dosage setting for radiation sterilization in accordance with ISO111737 in order to certificate if they are safe after radiation sterilization by use of platelet adhesion performance test, Ames test and the micronucleus test referred to ISO10993. It has been confirmed that after radiation sterilization the material have no genetic toxicity (not cause chromosomal aberrations) and can not increase the incidence of the micronucleus of the bone marrow polychromatocytes cells though there is no carcinogenic effects. Radiation sterilization does not affect the stability of the polyester polyethylene composite membrane/polyethylene (coronary artery stents). It means that as a good method radiation sterilization is worth to promote.关键词：Hemocompatibility;Radiation sterilization;Eratogenicity toxicity
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发布时间：2023-03-30 - 摘要：In order to investigate the protective effects of glucosinolate on the mice induced by 12C6+ ion beams the mice were fed orally with crude extracts of glucosinolate in various doses for two weeks, and then were whole-body irradiated with 2Gy 12C6+ ions. At 8h after irradiation the cell cycle status of the cells obtained from mice brain, lung and liver were measured by flow cytometry. The frequencies of cells with tail moment and the tail lengths were determined by the single cell gel electrophoresis. Compared with irradiation only group the percentages of cells in G0/G1 phase decreased statistically significantly, whereas the percentages in G2/M and S phases increased (p<0.05) in groups irradiated and treated with glucosinolate in lower doses. Similarly, the frequencies of cells with tail moment and the tail lengths induced by 12C6+ ion irradiation also decreased in brain, lung and liver cells (p<0.05). Nevertheless, no significant differences were observed in medium and higher doses groups irradiated and treated with glucosinolate by contrast with irradiation only group. The results show that the glucosinolate of lower doses can reduce the irradiation damages of mice induced by 12C6+ ion beams, and related protecting mechanism needs further exploration.关键词：Glucosinolate;12C6+ ions;Mice;Cell cycle;Single cell gel electrophoresis
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发布时间：2023-03-30 - 摘要：In order to suppress HSF1 gene expression using RNA interference technique and explore the changes of the radiation sensitivity of cervical carcinoma cells, HSF1-pSilencer2.1-U6neo for siRNA expression was transfected into cervical carcinoma cells by lipofectamine. HSF1mRNA expression was detected by real time polymerase chain reaction and flow cytometry was employed to evaluate HSF1protein expression. In addiction, the radiation sensitivity of cervical carcinoma cells was assessed by clone forming assay. The results show that HSF1mRNA expression of the cells transfected HSF1A-pSilencer2.1-U6neo descends obviously compared with control. Meanwhile the radiation sensitivity of Hela cells increases with the descension of HSF1 gene expression. Experiment has been confirmed that siRNA plasmid expression vector HSF1A-pSilencer2.1-U6neo successfully suppresses HSF1gene expression. Plasmid expression vector of HSF1 gene siRNA can be use to enhance the radio-sensitivity of cervical carcinoma cells and may be used as a powerfully adjunct method for conventional radiotherapy.关键词：Heat shock transcription factor1 (HSF1);RNA interference;Heat shock proteins;Radio-sensitivity
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发布时间：2023-03-30 - 摘要：In order to study the effects of microwave (MW) exposure on the mitochondrial transcription factor A(Tfam) expression in neurons and explore the relationship between Tfam and the energy metabolism disturbance the experiment model with exposing primary cultured cortical neurons to the microwave for 15min has been established in our group. The concentration of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) at 0h, 6h, 12h, 24h and 48h after exposure has been measured by high performance liquid chromatography (HPLC). And the real-time polymerase chain reaction (PCR) and fluorescence western-blot has been applied to detect the changes of the Tfam messenger ribonucleic acid (mRNA) and protein levels respectively. The results show that the concentration of ATP decreases in a time-dependent manner after exposure and both of the mRNA and protein expression of Tfam are up-regulated. It demonstrates that microwave exposure dramatically disturbs energy metabolism of neurons. However, newly-increased Tfam can’t up-regulate the ATP concentration as expected. It suggests microwave may have an adverse effect on the biological activity of Tfam in regulating the energy metabolism through inhibiting the import of Tfam from cytoplasm into mitochondria.关键词：Microwave;Neurons;Energy metabolism disturbance;Tfam
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发布时间：2023-03-30 - 摘要：This study is try to investigate the changes of PIG3 and GADD45 gene mRNA expression after irradiation and the probability of them as bio-dosimeters. In the dose-effect study, lymphoblastoid cells were irradiated by 60Co γ-rays with the doses of 0~10Gy and cultivated for 8 hours. Lymphoblastoid cells were cultivated for 0~72h after 5Gy irradiation for the time-effect study. The mRNA was extracted and real-time PCR method was used to detect the changes of PIG3 and GADD45 gene mRNA expression level in lymphoblastoid cells. The results show that PIG3 and GADD45 gene expression level in lymphocytes increases in a dose-dependent manner and has good dose-effect relationship. The time-effect curve indicates that the peak expression of PIG3 and GADD45 is at 8h after 5Gy irradiation and then begins to decrease gradually. PIG3 and GADD45 gene are sensitive to irradiation and both of them have dose-effect and time-effect relationships.关键词：Radiation injury;Lymphoblastoid cell line;PIG3;Gadd45;Gene expression
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发布时间：2023-03-30 - 摘要：The influence of irradiation doses on node number of sweet sorghum irradiated with 12C+6ions beam was studied and the length, weight and sugar brix of different internodes were measured. The results show that the difference of internodes number is not significant for different irradiation doses. Compared with control group, the averages of internodes length, node weight and node sugar brix of KFJT-1 increase with 0.6cm, 18.9g and 0.79% respectively.关键词：Sweet sorghum;12C+6ion beam;Node parameter
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发布时间：2023-03-30 - 摘要：Streptomyces roseosporus C20, the bacteria used in production of daptomycin, were implanted with (15~200)×1013/cm2 of 20keV N+ions. Survival rate of the bacteria at different absorbed doses was investigated, and mutagenic effects of the microbe were studied. After breeding under the selection pressure of resistance to streptomycin (the lethal concentration is 1.2μg/mL), several mutant strains with higher yields of daptomycin have been obtained. One of mutant strains, N3-36, can increase up to 126% compared to the original strain. It also shows that the mutant strains have high genetic stability.关键词：Dapotomycin;Ion implantation;Screening of streptomycin-resistance
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发布时间：2023-03-30
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