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1.
选用12C6+ 离子束对阿维链霉菌诱变选育高产菌株与原始菌株进行辐照诱变, 研究其累进辐照效应。实验结果表明,在辐照剂量为10 Gy时, 原始菌株比诱变高产菌株存活率高, 抗辐射能力强;辐照剂量高于30 Gy时,诱变高产菌株比原始菌株存活率高, 抗辐射能力强。原始菌株正突变率最高的辐照剂量为50 Gy, 致死率99.43%,正突变率最高, 达34.2%;对诱变高产菌株辐照剂量为30 Gy,致死率94.97%,正突变率最高, 达23.5% 。累进辐照效应降低了最佳辐照剂量。 Mutagenic effect on the mutant high producing strain ZJAV Y1 203 and the original strain ZJAV A1 irradiated by ion beam of 12C6+ have been investigated. The experimental results indicated that the original strain has higher survival rate and stronger resistance to radiation than mutant high producing Strain at dose of 10 Gy. The mutant high producing strain has higher survival rate and stronger resistance to radiation than the original strain at the dose higher than 30 Gy. The lethality was 97% and the highest rate of orthomutation was 34.2%, when ZJAV A1 was irradiated by 50 Gy 12C6+ beam. The lethality was 94.97% and the highest rate of orthomutation was 23.5% when ZJAV Y1 203 was irradiated by 30 Gy 12C6+ beam. The best radiation dose is decreased by progressivity irradiation.  相似文献   

2.
应用大剂量重离子束12C6+ 对菌株H3001 进行二次辐照选育,对初选获得的高产柠檬酸菌株进行摇瓶发酵试验及10~ 100 L 中试发酵罐试验,采用酸碱中和法测定发酵液中柠檬酸的含量。结果表明:当二次重离子12C6+剂量为857.8 Gy 时,致死率和正突变率达到最大值,分别为94.5% 和8%。通过摇瓶发酵试验,最终获得一株高产柠檬酸菌株hw317,控制该菌株发酵周期为60 h,柠檬酸酸度能达到19.2±0.2%。Heavy 12C6+ ion beams in various high doses were employed to irradiate H3001 strain for screening Aspergillus niger strain for hyper citric acid production. Three high-yield strains were obtained after shaker fermentation test. Among the three strains, the strain hw317 was implemented shaker fermentation for stability test and 10~100 L pilot fermentation tank for citric acid productive maximization. Acid-base neutralization method was applied to determinate the content of citric acid in fermented liquid. The results showed that: when the secondary heavy ion 12C6+ dose was 857.8 Gy, both of the fatality rate (94.5%) and the positive mutation rate (8%) were highest. Through the shaker fermentation tests and 10 ~ 100 L pilot fermentation test, one strain hw317 was screened and obtained for hyper citric acid production. Consequently, the final citric acid acidity can reach up to 19.2±0.2% with controlling fermentation cycle for 60 h.  相似文献   

3.
The effects of 12C+6 ion irradiation on colony morphology and mycelia morphology, as well as on mutation rate have been studied in the B1a high-product strains (ZJAV-Y1-203) mutated by heavy ion irradiation and compared with that in the original strain (ZJAV-A-1). After irradiating the rate of a straw hat colony type having a high ability of producing B1a in ZJAV-Y1-203 strains was higher than that found in ZJAV-A-1 strains. When strains were cultured in a liquid medium for 24 hours, the mycelium becoming thinner could be observed in all of the irradiated ZJAV- Y1-203 groups, but only in the ZJAV-A-1 groups irradiated at the dose of 50 Gy or more. The early growth of mycelium was inhibited in the ZJAV- Y1-203 group irradiated with a high dose. The highest positive mutation rate (23.5%) of ZJAV - Y1 - 203 was reached at the lower dose of 30 Gy while the highest positive mutation rate of 34.2% in ZJAV-A-1 appeared at 50 Gy.  相似文献   

4.
探讨了重离子束辐照后荷颊囊癌金黄地鼠血清中微量元素含量的变化趋势。采用0, 4, 6, 8和12 Gy剂量的12C6+ 离子束对荷颊囊癌金黄地鼠辐照治疗后28 d取血, 应用原子吸收光谱仪火焰法测定血清中Fe, Cu, Zn, Mg和Ca 5种微量元素的含量。金黄地鼠成瘤后, 血清中微量Cu, Zn, Ca和Mg元素含量下降, 均明显低于正常组(P<0.05); 不同剂量的重离子束辐照后28 d, 血清中5种微量元素在低剂量时均呈现继续下降趋势, 在6或8 Gy时恢复到正常组水平, 到12 Gy再呈降低的趋势, 存在一定的剂量-反应关系。重离子束辐照影响荷颊囊癌金地鼠血清微量元素的含量, 具有一定的临床意义。 To study the trend of the changes of trace elements in serum of golden hamster with cheek pouch carcinoma after irradiation by heavy ion beam, the cheek pouch carcinoma of golden hamster was exposed to different doses of heavy ion beam, after 4 weeks, the contents of Cu, Zn, Fe, Mg and Ca in serum were detected by flame method of Atomic Absorption Spectrometer. The contents of Cu, Zn, Ca and Mg in experimental groups with cheek pouch carcinoma were significantly lower than that of the normal group (P<0.05). After irradiated by 0, 4, 6, 8, 12 Gy heavy ion beam, the 4 Gy group showed a tendency downward, when the irradiation dose reached 6 Gy, the contents of Fe, Zn were increased, and decreased at 12 Gy. While Cu, Ca and Mg content of 8 Gy group rose to the highest, and decreased at 12 Gy. All of the results showed a dose reaction relationship (P<0.05). The irradiation of heavy ion beam maybe significantly affect the content of trace elements in serum of golden hamster with cheek pouch carcinoma.  相似文献   

5.
利用兰州重离子研究装置(HIRFL) 提供的12C6+ 离子束辐照菘蓝干种子(辐照剂量为10,35,60,90 和140 Gy,剂量率20 Gy/min),探讨了重离子束辐照对菘蓝M1代的生物学效应。研究发现,不同剂量的12C6+ 离子束辐照后,菘蓝种子的发芽率、成苗率、株高、根长和根冠比等生物学性状以及对菘蓝中靛玉红和4(3H) 喹唑酮含量均发生了变化,其中株高和根长随辐照剂量的增加而降低;菘蓝叶和根中的4(3H) 喹唑酮和靛玉红的含量随辐照剂量增加呈马鞍形增加关系。这表明:12C6+ 重离子束辐照菘蓝种子具有明显的当代损伤效应, 并可显著提高菘蓝中靛玉红和4(3H) 喹唑酮的含量,其辐照适宜诱变剂量为35 Gy。To investigate the M1 biological effects of heavy ions on Isatis indigotica Fort, its dry seeds were irradiated by 12C6+ beam with the dose of 0, 10, 35, 60, 90 and 140 Gy respectively,at the rate of 20 Gy/min delivered by the Heavy Ion Research Facility in Lanzhou (HIRFL). The results showed that biological characters such as germinating rate, germinating potential, survival rate, plant height, root height and root-shoot ratio were changed after irradiation. Moreover, the plant height and root height decreased in a dos dependent manner. The indirubin and 4(3H) quinazolinone content of Isatis indigotica Fort was improved and exhibited obviously “saddle” trends with irradiation dose increasing.Data suggest that exposure with low-dose 12C6+ to seeds of Isatis indigotica Fort has obvious injury effects at the first generation, and the active ingredient content of Isatis indigotica Fort may be improved by carbon ion beamirradiation. It is concluded that the suitable irradiation dose of mutation breeding is 35 Gy for the seeds of Isatis indigotica Fort.  相似文献   

6.
探讨了正常皮肤对重离子辐照急性损伤反应的耐受性, 为重离子治癌临床应用提供安全性检测的实验依据。实验前10 min, 实验猪肌肉注射复方氯胺酮1.2 mg/kg进行麻醉, 然后在兰州重离子研究装置(HIRFL)辐照终端利用12C6+束照射, 辐照剂量分别为0, 12, 21和27 Gy, 辐照分3次完成, 剂量率约为1.2 Gy/min, Bragg峰区照射, 辐照后每隔7 d对照射野拍照并活检取样, 做HE组织病理学观察。不同剂量12C6+离子束辐照实验猪皮肤后, 皮肤外观反应随辐照剂量增大而加快, 表现为肿胀和色素沉积等; 皮肤组织结构的变化明显, 上皮细胞排列紊乱、 萎缩、 空泡变性; 基本恢复正常所需时间也越长, 且都存在明显的剂量效应关系。结果表明, 辐照剂量范围为0—27 Gy时, 重离子对正常皮肤的辐照是安全的。The tolerance of the normal skin to the acute radiation injury reaction induced by heavy ion beams has been studied experimentally. The experimental pigs were injected with 1.2 mg/kg ketamine in 10 min before irradiation and were irradiated with 0, 12 , 21 and 27 Gy 12C6+ ion at a dose rate of 1.2 Gy/min at the Heavy Ion Research Facility in Lanzhou(HIRFL). The total radiation dose was finished by 3 times at Bragg Peak Region of Heavy Ion Beams.The radiation fields of skin were taken photo and performed biopsy. The contaneous tissues of radiation fields were stained by HE and examined histopatholo gical changes every seven days after irradiation. The results indicated that the cutaneous appearance reaction became more faster with radiation dosage rising and presented with swollen, melanin forming and so on after irradiated by the carbon ions at different dosage. The Pathological examination showed noticeable changes in histological and structural of experimental pigs skin, such as atrophy, vacuolation, denaturation and arranged irregularly in epithelial cells. Furthermore, the time for return to normality became longer with the increasing of radiation dosage. All indexes demonstrated correlation between the does and effects. It is concluded that the irradiation of heavy ion beams to normal skin is security when the radiation dose range is about 0—27 Gy.  相似文献   

7.
离子束辐照拟南芥生物学效应及其分子机理研究进展   总被引:2,自引:1,他引:1  
综述了离子束辐照拟南芥种子生物学效应、 生长发育变化、 向重力性等研究的最新进展。 阐释了离子束辐照拟南芥染色体DNA碱基变化、 DNA断裂或损伤、 染色体重组、 突变遗传性等分子机理。 探讨了离子束介导外源基因转化拟南芥的有效性和机理。 同时展望了辐照拟南芥分子机理研究中的辐射原初效应传递、 信号转导等其他机理研究及重离子辐射生物学效应的应用前景。 Newly research progresses were summarized in effect of ion beams on seed surface, biological effect, growth, development, gravitropism and so on. Furthermore, mutation molecular mechanism of Arabidopsis thaliana was discussed, for example, alteration of DNA bases, DNA damage, chromosomal recombination, characteristics of mutant transmissibility, etc. Meanwhile, the achievements of transferring extraneous gene to Arabidopsis thaliana by ion beams were reviewed in the paper. At last, the future prospective are also discussed here in mutation molecular mechanism and the potential application of biological effect of heavy ion beams.  相似文献   

8.
重离子束在微生物诱变育种及生物能源开发中的应用   总被引:4,自引:0,他引:4  
作为一种新型的辐射诱变源, 重离子束在辐射诱变育种中的优越性已经显现。 在此基础上综述了重离子束用于微生物诱变育种的基本原理、 独特优点、 所取得的成果及研究进展, 并对其在新型生物能源开发中的潜力进行了展望。As a new radiation source, heavy ion beams have demonstrated the outstanding advantage in mutation breeding. Based on this background, the basic principal and unique peculiarity of heavy ion beams, the achievement and the progress in the research of microbial mutation breeding are reviewed in the paper. The potential application of heavy ion beams to new biological energy is also prospected.  相似文献   

9.
以能量为80 MeV/u的12C6+离子为诱变源辐照油菜、 胡麻、 大葱和兵豆的干种子后, 研究了不同剂量处理对4种农作物M1和M2代种子出苗率及幼苗生长的影响。 实验结果表明: 重离子所导致的M1代生物学效应因不同的物种而表现出一定的差异, 适当剂量C离子辐照促进了油菜和胡麻M1代出苗率和幼苗的生长; 而不同剂量的C离子辐照抑制了大葱的出苗率和幼苗的生长; 兵豆3个剂量下的出苗率和对照相差很小, 但90 Gy辐照有利于其生长。 到了M2代, 4种作物辐照组的发芽率都低于各自的对照组; 30 Gy剂量下的油菜、 胡麻和兵豆长势最好; 大葱依然是对照的长势最好。 Crops of Brassica napus L., Linum usitatissmum L., Allium fistulosum L. and Lens culinaris Medic. were irradiated by 80 MeV/u 12C6+ ion beams with doses of 30, 90 and 180 Gy. The germination rates and heights of seedlings of M1 and M2 generation of these four plants were studied. The results indicated that germination rates and average heights of the B. napus and L. usitatissmum were improved by appropriate dose treatment, while great suppression was found in the irradiated groups of the A. fistulosum. As far as the L. Culinaris was concerned, little differences was observed on M1 germination rate, but the 90 Gy irradiation was favorable to growth of plant. The treatments with 30, 90 and 180 Gy were inferior to contrast one on M2 germination rate of the four species. Seedlings of M2 generation of the B. napus, L. sitatissmum and L. culinaris under 30 Gy grew better than the other groups, while the best performance of the A. fistulosum was shown by the control group.  相似文献   

10.
重离子束辐照育种研究进展及发展趋势   总被引:7,自引:1,他引:6  
相对于低能离子束生物学, 中能重离子束对植物的诱变效应介绍较少。 从机理上综述了中能重离子束辐照诱变技术的优点, 简要介绍了粮食作物、 经济作物及模式植物的重离子束辐照育种的现状, 最后从转基因、 分子辅助标记及航天育种等方面对重离子束辐照育种的发展趋势进行了展望。 In recent years, the intermediate energy heavy ion biology has been concerned rarely comparing to that of the low energy ions. In this paper, we summarized the advantage of a new mutation breeding method mediated by intermediate energy heavy ion irradiations. Meanwhile, the present state of this mutation technique in applications of the breeding in grain crops, cash crops and model plants were introduced. And the preview of the heavy ion irradiations in gene transfer, molecular marker assisted selection and spaceflight mutation breeding operations were also presented.  相似文献   

11.
马铃薯重离子辐射育种研究   总被引:3,自引:0,他引:3  
在2000—2005年将杂交技术和重离子辐射相结合, 采用55 MeV/u的 40Ar17+离子对马铃薯杂交种子和微型薯进行了不同剂量的贯穿辐射或离子注入处理。 结果表明, 对马铃薯微型薯进行重离子辐射能显著提高块茎的产量。 而杂交技术和重离子辐射相结合是一种更高效的育种方式, 不仅能提高块茎的增产幅度, 还能改善其加工品质。 微型薯重离子辐射的最佳剂量为60 Gy, 杂交种子辐射的适宜剂量范围在60—120 Gy之间。 通过对辐射后代的多年选育, 获得了几个产量显著高于对照、 品质优良的马铃薯新品系。 The effect of 55 MeV/u 40Ar17+ irradiation with different doses on hybrid seeds and micro tubers of potatoes were studied from year 2000 to 2005. The results showed that the yields of potatoes irradiated by heavy ions grew significantly. This new mutation method combining cross breeding technique with heavy ion irradiation is more effective, which could not only increase the yield of potatoes, but also improve their quality. The optimal mutagenic dose was 60 Gy to micro tubers of potatoes, 60—120 Gy to hybrid seeds, respectively. Finally, several new lines which have higher yield and better qualities were obtained through multi generation screening from the offspring of irradiated potatoes.  相似文献   

12.
本研究以拟南芥(Columbia野生型)干种子为材料,利用兰州重离子研究装置(HIRFL)产生的碳离子束对材料进行辐射处理,统计其存活率、根长、下胚轴长及每果荚种子数,以探讨不同传能线密度(Linear Energy Transfer,LET)的碳离子束辐照对拟南芥当代损伤效应的影响。结果表明,在相同LET辐射条件下,随着辐射剂量的增大,拟南芥的存活率、根长、下胚轴长度、每果荚种子数都呈现下降趋势。在相同剂量不同LET辐射处理情况下,随着LET的增大,存活率、根长、下胚轴长、每果荚种子数都显著下降,可见高LET辐射严重抑制了拟南芥的生长和发育。研究表明,当LET为50 keV/μm时,碳离子束辐射拟南芥干种子对应的最佳诱变剂量为200 Gy,为后续开展碳离子束辐射的诱变效率研究奠定了前期基础。Aimed to study the biological effects of carbon ion beams with different linear energy transfer (LET) values provided by Heavy Ion Research Facility in Lanzhou (HIRFL), dry seeds of Arabidopsis thaliana (Columbia-WT) were irradiated and a series of biological effects of postembryonic development, such as survival rate, primary root length, hypocotyls length and number of seeds per silique, were investigated. The results showed that, under the radiation condition of the same LET value, the survival rate, root length, hypocotyls length and number of seeds per silique were decreased with the increasing dose. In addition, under the radiation conditions with different LET values, but same dose, the extent of the decline of the survival rate, root length, hypocotyls length and number of seeds per silique were reinforced with the increasing LET. It was also found that high LET radiations inhibited the subsequent growth and development of Arabidopsis thaliana severely. In brief, it was suggested that the optimum dose of carbon ion beam with 50 keV/μm value on Arabidopsis thaliana dry seeds was 200 Gy. This research complemented the preliminary theoretical foundation for the comparative study of the highest mutation efficiency of carbon ion beam irradiations at IMP, CAS(Institute of Modern Physics, Chinese Academy of Sciences).  相似文献   

13.
~(12)C~(6+)离子束辐照紫苏干种子当代效应   总被引:2,自引:0,他引:2  
利用兰州重离子研究装置(HIRFL)提供的12C6+离子束辐照紫苏干种子(辐照剂量为40,80和120Gy,剂量率4Gy/min),探讨了重离子束辐照对紫苏M1代的生物学效应。结果发现,经不同剂量的12C6+离子束辐照后,紫苏种子的发芽率、发芽势、存活率、株高、分枝数、单株产量和千粒重等生物学性状均发生了变化,其中发芽势、单株产量和千粒重随辐照剂量的提高而降低,且有明显的剂量效应关系,但发芽率、大田成活率、株高和分枝数却随辐照剂量的增大,呈现出明显的"抛物线"趋势;紫苏幼苗根尖细胞的微核率和染色体畸变率随辐照剂量增加呈线性增加关系。这表明:12C6+重离子束辐照紫苏种子,具有明显的当代损伤效应,在本试验剂量范围内,低剂量辐照对发芽率和成活率有促进作用。  相似文献   

14.
重离子辐射具有独特的深度剂量分布和较高的相对生物学效应,被认为是理想的放疗手段。重离子的生物学效应在径迹形成过程中由多个物理参量共同决定,而这些物理参量和离子入射深度紧密相关,因此明确离子不同入射深度的生物学效应对重离子肿瘤放疗方案的设计和优化有着重要的理论和应用价值。使用兰州重离子研究装置HIRFL-CSRe 终端的碳离子束作为辐射源,以活体模式动物线虫作为实验对象,以线虫生殖细胞的凋亡水平作为生物学检测终点,研究了10 和20 Gy 碳离子辐射在辐射的入口、坪区和峰区的当代生物学效应和对后代个体基因组不稳定性的影响。结果表明:10 和20 Gy 碳离子辐射在三个不同的辐照区域内均显著增加了辐射当代的线虫生殖腺细胞的凋亡水平,并表现出一定的辐射区域和辐射剂量依赖性。同时,辐射诱导的后代个体基因组不稳定性也表现出一定的辐射区域和辐射剂量相关性。Heavy ion irradiation is a perfect means in radio-therapy due to its special depth dose distribution and high relative biological effects. The biological effects of heavy ion irradiation are determined by some major physical parameters, and vary along the tracks of heavy ions. Therefore, it is very significant for the tumor radio-therapy to investigate the biological effects along whole range of heavy ion radiation. In the present study, Caenorhabditis elegans, a model in vivo, was irradiated by carbon ion beams from HCRFL-CSRe, The level of germ cell apoptosis of worms was used as a checking endpoint for DNA damage, the effects of carbon irradiation located in the entrance, plateau and peak regions on the genomic instability of the irradiated worm and their progeny were detected. The results showed that the 10 and 20 Gy of carbon ion radiations led to the increased germ cell apoptosis in irradiated worms and these effects depend on the worm location along the range of carbon ions and the irradiation dosage. The results also suggested that heavy ion irradiation induced the up-regulated genomic instability in their progeny, and might be related to both the irradiation dose and the irradiated location.  相似文献   

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