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SO_2衍生物对大蒜根尖细胞遗传损伤作用的研究 被引量:21
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作者 仪慧兰 孟紫强 《环境科学学报》 CAS CSCD 北大核心 2001年第4期486-490,共5页
:研究SO2 体内衍生物———亚硫酸钠和亚硫酸氢钠混合液 (3:1,mol.L-1 mol.L-1)对大蒜幼根细胞的遗传损伤效应 .结果表明 :SO2 衍生物处理可导致根尖细胞分裂异常 ,中期染色体粘连、间期细胞微核和双核频率明显增高 ;此外还可引起根尖... :研究SO2 体内衍生物———亚硫酸钠和亚硫酸氢钠混合液 (3:1,mol.L-1 mol.L-1)对大蒜幼根细胞的遗传损伤效应 .结果表明 :SO2 衍生物处理可导致根尖细胞分裂异常 ,中期染色体粘连、间期细胞微核和双核频率明显增高 ;此外还可引起根尖部分细胞核碎解及核固缩 .SO2 体内衍生物的上述效应具有明显的时间 效应和剂量 展开更多
关键词 衍生物 大蒜 微核 双核 核碎解 核固缩 二氧化硫 根尖细胞 作物监测 遗传损伤作用
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离子与生物分子相互作用的微观动力学理论 被引量:7
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作者 张丰收 《原子核物理评论》 CAS CSCD 北大核心 2006年第1期23-34,共12页
对X射线、γ射线、电子、中子、质子和重离子等对生物体系的辐照研究现状进行了评论。重离子辐照中特有的倒转深度剂量分布,即Bragg峰,成为放射治疗的理想工具。通过对重离子辐照生物组织物理过程的分析,提出了重离子与生物分子相互作... 对X射线、γ射线、电子、中子、质子和重离子等对生物体系的辐照研究现状进行了评论。重离子辐照中特有的倒转深度剂量分布,即Bragg峰,成为放射治疗的理想工具。通过对重离子辐照生物组织物理过程的分析,提出了重离子与生物分子相互作用的三步物理过程,即核相互作用导致的核碎裂、库仑相互作用的电子激发和生物分子在周围环境相互作用下的弛豫,最终导致生物分子新结构的形成。由于物理过程是后期辐照化学过程、生物过程的基础,因此建立描述离子与生物分子相互作用物理过程的微观动力学理论是十分迫切的。 展开更多
关键词 重离子 生物分子 核碎裂 电子激发 弛豫
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Nuclear Track Detectors for Relativistic Nuclear Fragmentation Studies: Comparison with Other Competitive Techniques
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作者 Mukhtar Ahmed Rana Gul Sher +2 位作者 Shahid Manzoor Fariha Malik Kanwal Naz 《Modern Instrumentation》 2013年第3期49-59,共11页
The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using ... The potential of the high resolution nuclear track detector (NTD) CR-39 is examined carefully for the measurement of relativistic nuclear projectile fragmentation cross sections and studies of related processes using the experience of many years of such measurements. The charge resolution and the charge resolving power of CR-39 detectors for the measurements of 158 A GeV 207Pb projectiles and their fragments are presented. Exposures of target-detector stacks, the chemical etching procedure and the nuclear track measurements are described in detail discussing precautions and possible errors. The procedures discussed are also valid for other NTDs. A comparison with electronic active detectors is also made considering important detection and measurement aspects. An experimental design proposing the co-use of NTDs with in-use active detectors is described. 展开更多
关键词 nuclear Track Detection Methodology (NTDM) CR-39 Detectors nuclear fragmentation Charge Resolution fragmentation Cross SECTIONS
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500A MeV^(40)Ar与铜靶作用弹核碎裂电荷变化总截面及碎片产生分截面研究
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作者 李蓉 张东海 《山西师范大学学报(自然科学版)》 2023年第2期28-36,共9页
本文对最高能量为500 A MeV的^(40)Ar与铜靶作用弹核碎裂电荷变化总截面及碎片产生分截面进行了实验研究,并与相近能区^(40)Ar诱发铜靶核碎裂的实验结果及理论模型计算结果进行了比较.结果表明:电荷变化总截面与相近能区实验结果一致,也... 本文对最高能量为500 A MeV的^(40)Ar与铜靶作用弹核碎裂电荷变化总截面及碎片产生分截面进行了实验研究,并与相近能区^(40)Ar诱发铜靶核碎裂的实验结果及理论模型计算结果进行了比较.结果表明:电荷变化总截面与相近能区实验结果一致,也与Bradt-Peters及Nilsen半经验公式预言一致;NUCFRG2和PHITS模型预言低于实验结果.弹核碎片产生分截面在所研究的能区范围与束流能量没有明显依赖关系,EPAX3及FRACS半经验参数化公式可以较好地再现实验结果. 展开更多
关键词 核碎裂 电荷变化反应总截面 弹核碎片产生分截面
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Characterization of novel microsatellite markers of the Emei Shan Liocichla using restriction site-associated DNA sequencing 被引量:2
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作者 Ailin Yang De Chen +2 位作者 Pengcheng Wang Yiqiang Fu Zhengwang Zhang 《Avian Research》 CSCD 2017年第2期115-122,共8页
Background:The Emei Shan Liocichla(Liocichla omeiensis) is an endemic bird species to southwestern China with a small geographic range. However, little was known about the genetic status of this threatened species.Met... Background:The Emei Shan Liocichla(Liocichla omeiensis) is an endemic bird species to southwestern China with a small geographic range. However, little was known about the genetic status of this threatened species.Methods:We applied restriction-site-associated DNA sequencing(RAD-Seq) for rapid mass identification of microsatellite markers of the Emei Shan Liocichla.Results:A total of 11,564 microsatellite sequences were obtained, 600 random loci were designed for screening and 24 polymorphic microsatellite loci were selected for further validation. The average allele number, average observed heterozygosity and average expected heterozygosity were relatively low in our samples, which were 6.08, 0.6618 and 0.7048, respectively, indicating that the Emei Shan Liocichla might have lost some genetic diversity. Further analyses suggested that the populations distributed on two mountains(Daxiangling and Xiaoliangshan) showed a modest degree of genetic differentiation.Conclusions:These novel microsatellite markers provided valuable preliminary knowledge regarding the genetic status of the Emei Shan Liocichla and can be useful in further studies, as well as in the management and conservation of this species. 展开更多
关键词 Liocichla omeiensis fragmentation nuclear markers Genetic diversity Gene flow
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Projectile fragment emission in the fragmentation of 56Fe on Al,C,and CH2 targets
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作者 Luo-Huan Wang Liang-Di Huo +7 位作者 Jia-Huan Zhu Hai-Rui Duan Jing-Ya Wu Hui-Ling Li Jun-Sheng Li S.Kodaira N.Yasuda Dong-Hai Zhang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第12期119-129,共11页
The emission angle distribution of projectile fragments(PFs)and the temperature of PF emission sources for fragmentation of 56Fe on polyethylene,carbon,and aluminum targets at the highest energy of 497 A MeV are inves... The emission angle distribution of projectile fragments(PFs)and the temperature of PF emission sources for fragmentation of 56Fe on polyethylene,carbon,and aluminum targets at the highest energy of 497 A MeV are investigated on the basis of corrected data,using a CR-39 plastic nuclear track detector.It is found that the average emission angle of PFs increases with the decrease in PF charge for the same target,and no obvious dependence of angular distribution on the mass of the target nucleus is found for the same PF.The cumulative squared transverse momentum distribution of PFs can be well represented by a single Rayleigh distribution.The temperature of PF emission sources is extracted from the distribution,and it is about 1.0-8.0 MeV and does not depend on the mass of the target for PFs with charges of 9≤Z≤25. 展开更多
关键词 HEAVY-ION collision PROJECTILE fragmentation nuclear temperature CR-39 plastic nuclear track detector
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Forward–backward emission of target evaporated fragments in high energy nucleus–nucleus collisions 被引量:1
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作者 张智 马田丽 张东海 《Chinese Physics C》 SCIE CAS CSCD 2015年第10期29-34,共6页
The multiplicity distribution, multiplicity moment, scaled variance, entropy and reduced entropy of target evaporated fragments emitted in forward and backward hemispheres in 12 A GeV ^4He, 3.7 A GeV ^16O, 60 A GeV ^1... The multiplicity distribution, multiplicity moment, scaled variance, entropy and reduced entropy of target evaporated fragments emitted in forward and backward hemispheres in 12 A GeV ^4He, 3.7 A GeV ^16O, 60 A GeV ^16O, 1.7 A GeV ^84Kr and 10.7 A GeV ^197Au -induced emulsion heavy target (AgBr) interactions are investigated. It is found that the multiplicity distribution of target evaporated fragments emitted in both forward and backward hemispheres can be fitted by a Gaussian distribution. The multiplicity moments of target evaporated particles emitted in the forward and backward hemispheres increase with the order of the moment q, and the secondorder multiplicity moment is energy independent over the entire energy range for all the interactions in the forward and backward hemisphere. The scaled variance, a direct measure of multiplicity fluctuations, is close to one for all the interactions, which indicate a correlation among the produced particles. The entropy of target evaporated fragments emitted in both forward and backward hemispheres are the same within experimental errors. 展开更多
关键词 relativistic heavy-ion collisions target fragmentation MULTIPLICITY nuclear emulsion
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Fragmentation in ^16 O-emulsion interactions at 3.7 A GeV 被引量:1
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作者 张东海 李振宇 +1 位作者 刘惠玲 李俊生 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第12期2451-2457,共7页
The topology of ^16 O fragmentation at 3.7 A GeV in reactions with emulsion nuclei is presented. The multiplicity distributions of projectile fragments, charged secondaries and their dependences on the projectile resi... The topology of ^16 O fragmentation at 3.7 A GeV in reactions with emulsion nuclei is presented. The multiplicity distributions of projectile fragments, charged secondaries and their dependences on the projectile residues are discussed. 展开更多
关键词 relativistic heavy-ion collision projectile fragmentation nuclear emulsion
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Effects of Diabetes Mellitus upon Sperm Quality Insight into Molecular Level
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作者 Anna Papadopoulou Petros Karkalousos Maria Trapali 《Journal of Diabetes Mellitus》 2022年第2期75-86,共12页
Diabetes Mellitus is a chronic disease that affects important body organs in a very serious manner. The consequences of this disease turn out to be a significant problem for the patient, who tries to cope with the new... Diabetes Mellitus is a chronic disease that affects important body organs in a very serious manner. The consequences of this disease turn out to be a significant problem for the patient, who tries to cope with the new condition his organism has been placed in. The most common effect of the disease, hyperglycaemia, leads over time to serious damage to various body systems, such as nerves and blood vessels. What is not widely known among the population is that diabetes may have harmful effects on the reproductive system of the men suffering from diabetes type 1 and 2 and that such a parameter could lead to or might be the reason for infertility problems for couples, for example, miscarriage or embryonic failure. AGEs is a number of products which are believed to play an important role, because their presence has been detected in increased level in diabetic men. This implies that those glycation products might play a key role in diabetic complications. Their receptor, RAGE, member of the immunoglobulin superfamily has been detected in the reproductive tract of diabetic men. Reactive oxygen species (ROS), a possible product of AGEs appear in high levels in seminal plasma and are believed to be the cause of DNA fragmentation. The objective of this review was to gather all the available material i.e. studies on diabetes mellitus in one article, to study the research which has already been conducted and the conclusions that have been drawn, in order to offer, if possible, new pathways and perspectives to the scientists, who focus on fertility problems, sometimes intractable. 展开更多
关键词 DIABETES nuclear fragmentation Sperm Quality ROS Sperm Motility Sertoli Cells RAGE Sperm Structure Gene Expression
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北京放射性核束设施及核物理基础研究展望 被引量:1
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作者 郭冰 柳卫平 《科学通报》 EI CAS CSCD 北大核心 2015年第19期1820-1827,共8页
放射性核束物理与核天体物理是物理学基础研究的前沿方向,其需求是建造大型放射性核束设施的主要推动力.本文简要介绍了放射性核束物理与核天体物理,比较了产生放射性核束的在线同位素分离(ISOL)方法与炮弹碎裂(PF)方法,综述了国内外已... 放射性核束物理与核天体物理是物理学基础研究的前沿方向,其需求是建造大型放射性核束设施的主要推动力.本文简要介绍了放射性核束物理与核天体物理,比较了产生放射性核束的在线同位素分离(ISOL)方法与炮弹碎裂(PF)方法,综述了国内外已有的ISOL型装置情况,并具体介绍了北京放射性核束设施,对其未来核物理基础研究给予展望. 展开更多
关键词 放射性核束物理 核天体物理 在线同位素分离 炮弹碎裂 北京放射性核束设施
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Universal Behavior of Nuclear Fragmentation
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作者 Zheng, Yuming Richert, Jean Wagner, Pierre 《Chinese journal of nuclear physics》 EI 1995年第3期215-220,共6页
We use the bond percolation model to study the multifragrnentation of<sup>197</sup>Au projectiles interact-ing with Cu target at a bombarding energy of 600 MeV/u.The charge observables and some of their di... We use the bond percolation model to study the multifragrnentation of<sup>197</sup>Au projectiles interact-ing with Cu target at a bombarding energy of 600 MeV/u.The charge observables and some of their dif-ferential distributions are analyzed.The theoretical results agree well with the experimental data ofALADIN collaboration.This indicates that the percolation model can describe reasonably the universal be-havior of nuclear fragmentation in nucleus-nucleus collisions. 展开更多
关键词 nuclear fragmentation UNIVERSAL BEHAVIOR BOND PERCOLATION model Heavy ion COLLISION
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Helium production from ^84Kr- and ^197Au-emulsion interactions at high energies
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作者 张东海 程锦霞 +6 位作者 成宾 王芳 王琦 张海青 许蓉 贾会明 李雪琴 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第2期531-536,共6页
The properties of the relativistic helium fragments produced in interactions of ^84Kr at 1.8 A GeV and ^197Au at 10.7 A GeV in emulsion are investigated. The experimental results are compared with those obtained from ... The properties of the relativistic helium fragments produced in interactions of ^84Kr at 1.8 A GeV and ^197Au at 10.7 A GeV in emulsion are investigated. The experimental results are compared with those obtained from various projectiles with emulsion collisions at different energies. It is found that the multiplicity distribution of helium projectile fragments (HPFs) is well described by the Koba-Nielsen Olesen (KNO) scaling presentation. The second Mueller moment f2 of the HPF multiplicity distribution is independent of the projectile energy for the same projectile, but it is dependent on the projectile mass number. The value of f2 increases with the increase of projectile mass number Ap. The negative value of f2, when Ap 〈 69, means that the emission of HPFs is anticorrelated, but positive value of f2, when Ap 〉 69, refers to that the emission of HPFs is correlated. The non-zero f2 moment in this experiment implies the strong correlation existing between the HPFs. 展开更多
关键词 relativistic heavy-ion collisions projectile fragmentation nuclear emulsion
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Forward-backward multiplicity correlations of target fragments in nucleus-emulsion collisions at a few hundred MeV/u
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作者 张东海 陈艳玲 +7 位作者 王国蓉 李王东 王青 姚继杰 周建国 李蓉 李俊生 李惠玲 《Chinese Physics C》 SCIE CAS CSCD 2015年第1期19-30,共12页
The forward-backward multiplicity and correlations of a target evaporated fragment (black track particle) and target recoiled proton (grey track particle) emitted from 150 A MeV 4He, 290 A MeV ^12C, 400 A MeV ^12C... The forward-backward multiplicity and correlations of a target evaporated fragment (black track particle) and target recoiled proton (grey track particle) emitted from 150 A MeV 4He, 290 A MeV ^12C, 400 A MeV ^12C, 400 A MeV ^20Ne and 500 A MeV ^56Fe induced different types of nuclear emulsion target interactions are investigated. It is found that the forward and backward averaged multiplicity of a grey, black and heavily ionized track particle increases with the increase of the target size. The averaged multiplicity of a forward black track particle, backward black track particle, and backward grey track particle do not depend on the projectile size and energy, but the averaged multiplicity of a forward grey track particle increases with an increase of projectile size and energy. The backward grey track particle multiplicity distribution follows an exponential decay law and the decay constant decreases with an increase of target size. The backward-forward multiplicity correlations follow linear law which is independent of the projectile size and energy, and the saturation effect is observed in some heavy target data sets. 展开更多
关键词 heavy-ion collisions target fragmentation MULTIPLICITY correlation nuclear emulsion
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Multiplicity fluctuation analysis of target residues in nucleusemulsion collisions at a few hundred MeV/nucleon
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作者 张东海 陈艳玲 +8 位作者 王国蓉 李王东 王青 姚继杰 周建国 郑素华 胥利玲 苗惠锋 王鹏 《Chinese Physics C》 SCIE CAS CSCD 2014年第7期14-17,共4页
Multiplicity fluctuation of the target evaporated fragments emitted in 290 MeV/u 12C-AgBr, 400 MeV/u 12C-AgBr, 400 MeV/u 20Ne-AgBr and 500 MeV/u 56Fe-AgBr interactions is investigated using the scaled factorial moment... Multiplicity fluctuation of the target evaporated fragments emitted in 290 MeV/u 12C-AgBr, 400 MeV/u 12C-AgBr, 400 MeV/u 20Ne-AgBr and 500 MeV/u 56Fe-AgBr interactions is investigated using the scaled factorial moment method in two-dimensional normal phase space and cumulative variable space, respectively. It is found that in normal phase space the scaled factorial moment (ln(Fq)) increases linearly with the increase of the divided number of phase space (lnM) for lower q-value and increases linearly with the increase of lnM, and then becomes saturated or decreased for a higher q-value. In cumulative variable space ln(Fq) decreases linearly with increase of lnM. This indicates that no evidence of non-statistical multiplicity fluctuation is observed in our data sets. So, any fluctuation indicated in the results of normal variable space analysis is totally caused by the non-uniformity of the single-particle density distribution. 展开更多
关键词 heavy-ion collisions target fragmentation non-statistical fluctuation nuclear emulsion
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Single source emission of proton projectile fragments in nucleus-emulsion interactions
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作者 张东海 李俊生 李惠玲 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期102-107,共6页
The projected angular distribution and transverse momentum distribution of proton projectile fragments produced in 3.7A GeV 160, 500A MeV 56Fe, and 1.7A GeV S4Kr induced by different kinds of emulsion target (H, CNO,... The projected angular distribution and transverse momentum distribution of proton projectile fragments produced in 3.7A GeV 160, 500A MeV 56Fe, and 1.7A GeV S4Kr induced by different kinds of emulsion target (H, CNO, and AgBr) interactions are investigated. It is found that the projected angular distribution and transverse momentum distribution can be well represented by a single Gaussian distribution. Comparison of transverse momentum distribution with the Maxwell-Boltzmann distribution reveals that proton projectile fragments are emitted from a single-temperature emission source. The temperature is different for different colliding systems, and linearly depends on the target size. 展开更多
关键词 nucleus nucleus collision proton projectile fragments projectile fragmentation nuclear emulsion
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核碎裂在离子与生物分子相互作用中的效应 被引量:1
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作者 张丰收 《原子核物理评论》 CAS CSCD 北大核心 2005年第4期373-375,共3页
讨论了重离子辐照生物中核碎裂效应,给出与此相关的核碎裂研究现状和进展。
关键词 重离子 生物分子 核碎裂
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290MeV/u9C离子束在液态水靶中输运的蒙特卡洛模拟
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作者 奉光华 左国平 +1 位作者 龚学余 康玺 《核技术》 CAS CSCD 北大核心 2012年第1期65-68,共4页
9C离子束是双重辐射源于在治疗肿瘤有明显优势。我们用蒙特卡洛程序FULKA模拟了290 MeV/u 9C离子束在水靶中的输运,研究其能量沉积、核碎片分布以及核碎片注量的深度分布,可为9C离子束肿瘤治疗剂量学提供参考。
关键词 9C离子束 核碎片 布拉格峰 能量沉积
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细胞凋亡过程中核碎裂形成的方式及其意义 被引量:1
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作者 邓丽英 张云汉 +1 位作者 许平 张红新 《临床与实验病理学杂志》 CAS CSCD 1999年第3期233-234,I036,共3页
目的:观察抗癌药物诱导的肿瘤细胞凋亡中核碎裂的形式并探讨其意义。方法:用光镜和电镜观察人食管癌Eca109细胞经顺铂(DDP)和5氟尿嘧啶(5Fu)处理后的形态学改变。结果:肿瘤细胞的死亡特征符合凋亡,这两种抗... 目的:观察抗癌药物诱导的肿瘤细胞凋亡中核碎裂的形式并探讨其意义。方法:用光镜和电镜观察人食管癌Eca109细胞经顺铂(DDP)和5氟尿嘧啶(5Fu)处理后的形态学改变。结果:肿瘤细胞的死亡特征符合凋亡,这两种抗癌药物引起的细胞后期的改变(如核碎裂、细胞出芽、凋亡小体形成以及凋亡小体被吞噬)相同,然而细胞核的早期改变有所不同。DDP处理后核染色质呈粗网状、出芽,而5Fu处理后核染色质呈粗块状聚集于核膜下、核膜崩解。结论:细胞凋亡过程中核碎裂可通过多种途径发生,这对于机体可能具有重要的生理学意义。 展开更多
关键词 食管肿瘤 细胞核碎裂 细胞凋亡
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60A GeV氧原子核在核乳胶中四分裂事例的遍举测量 被引量:1
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作者 张东海 孙君芬 郑蒲英 《原子能科学技术》 EI CAS CSCD 北大核心 1990年第3期49-51,共3页
一、引言裂变是原子核的一种重要运动形态,对裂变现象及其机制的研究是原子核物理学的一个重要方面。对于静止靶核的裂变已经进行过大量的研究,但对相对论性原子核的裂变现象的研究还刚刚开始。EMU-01国际合作组用西欧核子中心SPS加速器... 一、引言裂变是原子核的一种重要运动形态,对裂变现象及其机制的研究是原子核物理学的一个重要方面。对于静止靶核的裂变已经进行过大量的研究,但对相对论性原子核的裂变现象的研究还刚刚开始。EMU-01国际合作组用西欧核子中心SPS加速器把^(16)O加速到15,60和200A GeV,为核物理和粒子物理的研究开辟了一个新的领域。 展开更多
关键词 核乳胶 原子核 碎裂
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两种抗癌药诱导细胞凋亡的形态学比较 被引量:1
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作者 邓丽英 杨建斌 +2 位作者 原学斌 贾翠玲 张云汉 《长治医学院学报》 1998年第2期95-96,共2页
用光镜、电镜观察了顺铂和5—氟尿嘧啶两种抗癌药作用于人食管癌Eca-109细胞后细胞凋亡的形态学变化并进行了比较。结果表明这两种抗癌药均可诱导Eca-109细胞凋亡,细胞最终发生核碎裂及凋亡小体形成,然而两者引起的细... 用光镜、电镜观察了顺铂和5—氟尿嘧啶两种抗癌药作用于人食管癌Eca-109细胞后细胞凋亡的形态学变化并进行了比较。结果表明这两种抗癌药均可诱导Eca-109细胞凋亡,细胞最终发生核碎裂及凋亡小体形成,然而两者引起的细胞凋亡早期的变化有所不同。结果提示,细胞凋亡可通过多种途径发生。 展开更多
关键词 抗癌药 细胞凋亡 核染色质 核碎裂
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