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1.
张现忠  温海涛  王学斌 《同位素》2003,16(3):147-150
以99TcmO4-淋洗液为起始物,在低压条件下制备了中间体[99Tcm(CO)3(H2O)3]+,并通过配体交换反应得到放化纯度大于90%的[99Tcm(CO)3(CHI)3]+配合物.该配合物在室温下放置6 h以上放化纯度无明显变化.在正常昆明小鼠体内的生物分布实验结果表明,[99Tcm(CO)3(CHI)3]+具有一定的心肌摄取,且滞留也相当好;在注射后5 min和60 min时的心肌摄取值分别为(13.59±2.12)%ID/g和(13.87±1.54)%ID/g.尽管该配合物的肝和肺本底摄取较高,但是与99TcmN-CHI和99Tcm-CHI相比,羰基锝中心核的引入还是大大改善了配合物用于心肌显像的性能,为发展新的心肌显像剂提供了一种新思路.  相似文献   

2.
《同位素》2014,(4)
为研制新型的PET心肌灌注显像剂,设计合成了18 F标记的鏻正阳离子:3-氟-18 F-甲基苄基-三-(2,6-二甲氧基苯基)鏻盐(18F-2),并进行了小鼠生物分布研究。18F-2采用一锅法制备得到,总的标记时间小于60min,校正后的产率为(31±3)%,放化纯度95%;小鼠生物分布结果表明,18 F-2在小鼠心肌中有很高的初始摄取和良好的滞留,给药后2min和60min的心肌摄取分别为(53.88±7.45)%ID/g和(23.93±3.28)%ID/g;其在肝、肺、血等非靶组织中的摄取低,且清除快,给药后60min心与肝、心与肺、心与血放射性摄取比分别为3.99、3.80和9.17。值得进一步深入研究。  相似文献   

3.
研究了153Sm标记盐酸平阳霉素的条件以及标记物在荷S - 180肉瘤小鼠体内的分布情况。结果表明 :当pH为 5— 6,盐酸平阳霉素的量为 1mg时 ,加入适量放射源153SmCl3 溶液 ,室温反应30min可得到标记率 >98%的153Sm -盐酸平阳霉素溶液。室温下放置 72h后 ,放化纯度仍高达 97.2 %。向荷S - 180肉瘤小鼠的静脉中注入该标记物 ,分别在 3、6、12、2 4h处死 ,器官的放射性分布数据显示一定的肿瘤摄取和较高的骨摄取 ,最高分别可达 ( 1.615± 0 .2 19) %ID g和 ( 16.142± 3.50 1) %ID g ,瘤 血和骨 血最高可达 4 8和 90 8。  相似文献   

4.
为探讨131I标记毒死蜱(Chlorpyrifos, CPF)在小鼠体内的分布特点,采用Iodogen法对CPF进行131I标记,KM小鼠尾静脉注射131I-CPF(185 kBq/只,n=5),分别于注射后5、10、30、60、120、240、1440 min取各脏器,计算每克组织摄取注射剂量的百分率(%ID/g)。结果显示,131I-CPF标记率达93.5%,放化纯度为96.9%,131I-CPF在小鼠体内广泛分布,主要经肺、胃、小肠、大肠、肌肉和颌下腺吸收,其放射性摄取率在注药后 10 min 时达高峰,分别为37.12%ID/g、6.18%ID/g、8.12%ID/g、8.15%ID/g、7.04%ID/g和7.02%ID/g;经肝和肾进行代谢,其放射性摄取率在5 min时分别为4.34%ID/g和8.50%ID/g, 4 h为0.22%ID/g和 0.69%ID/g。血液中放射性清除较快,放射性摄取率在注入后5 min时为37.27%ID/g,4 h为1.35%ID/g。碘标记CPF体外稳定,体内主要经肺和消化道吸收,肝、肾代谢,可用于进一步的微量示踪研究。  相似文献   

5.
通过131I标记锰卟啉(MnTBAP)探讨锰卟啉在小鼠体内的分布代谢。采用Iodogen法对锰卟啉进行131I标记;以聚酰胺薄膜为支持介质、生理盐水为展开剂,测定标记物的标记率和放化纯度;KM小鼠尾静脉注射131I-MnTBAP(每只185kBq,n=6),分别于注射后5、10、30、60、120、240、1 440min取各脏器,称重、测定计数率,计算每克组织摄取注射剂量的百分率(%ID/g)。结果表明,131I-MnTBAP标记率达96.3%,其放化纯在标记后2、24、48h分别为96%、95%、94.5%;动物实验显示131I-MnTBAP在小鼠体内广泛分布,主要经肝和肾脏进行代谢,肝、肾的放射性摄取在注入后5min时分别为8.34%ID/g、12.23%ID/g,4h时则分别下降为0.34%ID/g、0.73%ID/g,血液中放射性清除较快,注入后5min时血液中放射性摄取为5.55%ID/g,4h为0.86%ID/g。因此,碘标记锰卟啉的标记物体外稳定,体内主要经肝、肾代谢,可用于进一步的微量示踪研究。  相似文献   

6.
以SnCl2 ·2H2 O为还原剂 ,N 甲基二硫代肼甲酸甲酯 (DTCZ)为N3- 离子提供体制备[99TcmN]int2 + 中间体 ,然后与配体二水·N 环庚基 二硫代氨基甲酸钠 (CHPDTC)发生配体交换反应 ,得到放化纯大于 90 %的99TcmN CHPDTC配合物。99TcmN CHPDTC在制备后放置 7h放化纯不变 ,分配比lgD =1 5 0。小鼠体内生物分布结果表明 ,99TcmN CHPDTC有较高心肌摄取和较好的心肌滞留。在注射后 5 ,30 ,60min时 ,心肌摄取量 (ID/ (%·g- 1) )分别为 17 17,16 82 ,19 18。在注射后 60min时 ,R(心 /血 ) ,R(心 /肺 ) ,R(心 /肝 )比值分别为 7 10 ,1 4 3,0 4 1。有望成为新型心肌灌注类显像剂  相似文献   

7.
以氯化亚锡为还原剂制备了99Tcm-CQDO及其甲基硼酸加成物99Tcm-CQDO-MeB,经萃取纯化,其放化纯度均>90%.小鼠体内分布表明,两者均能被小鼠心肌迅速摄取;99Tcm-CQDO的心肌清除快,10min时已清除至(5.88±1.66)%ID/g;而99Tcm-CQDO-MeB在心肌内却有较长的滞留时间,60min时心肌摄取仍有(7.42±0.17)%ID/g.两者在血中清除均符合双指数二室模型,T1/2α分别为1.38min和1.51min.pH为7.40时,99Tcm-CQDO和99Tcm-CQDO-MeB的分配系数分别为25和12.  相似文献   

8.
余媛 《同位素》2006,19(2):92-96
采用国产盐酸环丙沙星原料药,研究确定了99Tcm-环丙沙星(ciprofloxacin ,CPF)的最佳标记条件,在此基础上制备环丙沙星冻干品药盒,并初步研究了99Tcm-CPF在炎症模型小鼠体内的分布。结果显示最佳标记条件为:盐酸环丙沙星的用量大于4 mg;SnCl2•2H2O的用量大于100μg;体系pH为3.0~3.5;反应时间约10 min。最佳标记条件下制备的99Tcm-CPF放化纯度>95%,室温放置6 h,其放化纯度无明显变化;药盒分别在0~8 ℃冷藏及-18 ℃冷冻保存3个月后再标记,标记物的放化纯度仍>95%;小鼠炎症模型实验结果显示,注射后4 h脓肿与肌肉放射性摄取比为4.30±0.31。  相似文献   

9.
以SnCl2 · 2H2 O为还原剂 ,丁二酰二酰肼 (SDH )为N3- 离子提供体 ,在室温下制备[99TcmN]2 +int 中间体 ,然后与二水·N 环己基 二硫代氨基甲酸钠 (CHDTC)发生配位体交换反应得到放化纯大于 90 %的99TcmN CHDTC配合物。小鼠体内的生物分布实验表明 ,99TcmN CHDTC有较高的脑摄取和较好的脑滞留。注射后 5,30 ,6 0min时 ,脑摄取量 (% /g)分别为 2 91,5 88,5 91,R(脑 /血 )比值分别为 0 14,1 4 6 ,2 10。99TcmN CHDTC在心肌中也有较高的摄取 ,但R(心 /肝 )比值低。采用甲脒亚磺酸 (FSA)作还原剂对配位体CHDTC进行99Tcm 直接标记 ,其在小鼠体内的生物分布结果表明 ,99Tcm CHDTC主要蓄积在肝脏 ,脑、心肌摄取很少。这表明放射性药物分子中引入 [99TcmN]2 +核会引起生物分布性质的明显改变  相似文献   

10.
通过氨基甲基化的方法用碳-11甲基标记了N-甲基苯乙胺、N-甲基间羟基苯乙胺和N-甲基酪胺三种化合物,评价了放射性核素标记的三种化合物在昆明小鼠体内的生物分布特征。合成结果显示,[11 C]-N-甲基苯乙胺合成包括HPLC分离总耗时约30min,放化产率为25%、放化纯度98%,[11 C]-N-甲基间羟基苯乙胺合成包括HPLC分离总耗时约25min,放化产率为13%、放化纯度97%,[11 C]-N-甲基酪胺合成包括HPLC分离总耗时约25min,放化产率为28%、放化纯度98%;小鼠体内生物分布结果显示:三个标记物在各测定时间点小鼠靶器官心肌的摄取均比肺、肝、脾、肾等非靶器官的摄取低,心肌摄取与肌肉摄取相近。注射后10min时[11 C]-N-甲基苯乙胺的心与肺放射性摄取比为1/2.08、心与肝为1/2.94,[11 C]-N-甲基间羟基苯乙胺的心与肺放射性摄取比为1/2.56、心与肝为1/2.76,[11 C]-N-甲基酪胺的心与肺放射性摄取比为1/1.85、心与肝为1/5。以上结果提示,碳-11甲基标记N-甲基苯乙胺、N-甲基间羟基苯乙胺和N-甲基酪胺的合成方法虽然简单,但是心肌靶向性差,不适用于核素心肌显像。  相似文献   

11.
Food irradiation is gaining popularity worldwide and this technology is important to improve quality and reduce the post harvest losses of food. Because of the rapid commercialization of irradiated foods throughout the world, compliance of different regulations relating to use of technology in different countries and demand of consumers for clear labelling of irradiated foods, there is need for the development of analytical methods to detect radiation treatment of food. Among several methods studied so far, thermoluminescence (TL) is an important method that can be used to find out the irradiation history of food that contain even a very minute amount of dust particles. In this study, the irradiated and unirradiated wheat and rice samples were analyzed using the TL method. The samples were purchased from the local market of Peshawar and irradiated to radiation doses of 0.5 and 1.0 kGy using Co-60 gamma irradiator at the Nuclear Institute for Food and Agriculture (NIFA), Peshawar. The mineral contaminants were isolated by jet water, ultrasonic treatment, and density gradient. TL glow curves of the isolated minerals from irradiated and unirradiated samples were recorded between the temperature ranges of 50-500℃ using a TL reader. Generally, the glow curves for irradiated samples showed much higher TL intensities (TL1) than the unirradiated samples. The results were normalized by rerradiation of mineral samples to gamma-ray dose of 1.0 kGy followed by determination of the second glow curves (TL2). The ratio of the area of first glow curve to that of second glow curve (TL1/TL2) was calculated for selected temperature intervals and compared with the recommended values for unirradiated and irradiated samples. Finally, the shapes of the glow curves for irradiated and unirradiated samples were also analyzed. On the basis of these results (comparison of TL-intensities, TL1/TL2 ratios and shapes of the glow curves), all the irradiated and unirradiated samples of wheat and rice were unequivocally identified.  相似文献   

12.
The paper is to study pharmacologic characteristics of 18F-FP-β-CIT (18F-N-(3-fluoropropyl)-2β- carbomethoxy-3β- (4-iodophenyl)nortropane) as an imaging agent for dopamine transporter. The radiochemical purity of 18F-FP-β-CIT in aqueous solution was over 95% after standing at room temperature for 4h. Biodistribution displayed rapid uptake in rat brain (1.375 %ID/organ at 5min and 0.100 %ID/organ at 180 min) and the striatal uptake was 1.444,0.731, 0.397, 0.230 and 0.146 %ID/g at 5, 30, 60, 120 and 180 min, respectively. The values of striatum/cerebellum,striatum/frontal cortex and striatum / hippocampus in rat's brain at 30 min were 3.38, 2.17 and 2.40 respectively. The uptake in striatum can be blocked by β-CFT, suggesting that 18F-FP-β-CIT binds to DAT peculiarly. The compound was rapidly cleared from monkey's blood. The striatal uptake was bilaterally decreased in the left-sided lesioned PD rats, compared with normal control. Brain PET imaging studies in normal monkey showed that 18F-FP-β-CIT was concentrated in striatum. The test of undue toxicity showed that the dose received by mice was 1250 times as by human, which indicates that 18F-FP-β-CIT is very safe. So 18F-FP-β-CIT is a promising PET imaging agent for DAT with safety and validity.  相似文献   

13.
14.
Soil samples in and around salt field area have been analyzed for natural radioactivity concentration using gamma ray spectrometer.The activity concentration for ~(232)Th,~(238)U and ~(40)K are ranged from 27.88 to 45.27 Bq/kg, from BDL to 13.30 Bq/kg,and from 135.54 to 381.28 Bq/kg,respectively.The measured activity concentrations for these radionuclides were compared with world average activity of soil.The average activity concentration of ~(232)Th in the present study is 1.19 times higher than world median value while the activity of ~(238)U and ~(40)K is found to be lower. The absorbed dose rates due to these radionuclides were calculated.The average absorbed gamma dose rate due to the presence of ~(232)Th,~(238)U and ~(40)K in soil samples is 36.99 nGy·h~(-1).These results indicate no radiological anomaly. The data presented in this study will serve as a base line survey for primordial radionuclides concentration in the study area.  相似文献   

15.
Due to relatively high uptake of glucose in the brain cortex, the use of FDG PET imaging is greatly limited in brain tumor imaging, especially for low-grade gliomas and some metastatic tumours. More and more tracers with higher specificity were developed lately for brain tumor imaging. There are 3 main types of non-FDG PET tracers: amino acid tracers, choline tracers and nucleic acid tracers. These tracers are now widely applied in many aspects of brain tumor imaging. This article summarized the general use of non-FDG PET in different aspects of brain tumor imaging.  相似文献   

16.
在军控核查中,核部件的质量、丰度、年龄属性需采用无损方法进行核查,NPL-NMC系统是一套利用中子多重性测量核部件质量属性的装置,为建立完善的属性测量系统,还需在NPL-NMC系统的基础上建立γ测量子系统。本文通过设计γ测量子系统在NPL-NMC系统上的布局及对中子屏蔽的优化,使系统能对铀部件的丰度、年龄属性进行测量。模拟计算结果表明,该γ测量子系统能很好地满足军控核查对铀部件丰度、年龄属性测量的要求。  相似文献   

17.
Carbon fiber-reinforced advance composites have been used for structural applications,mainly on account of their mechanical properties.The main factor for a good mechanical performance of carbon fiber-reinforced com- posite is the interfacial interaction between its components,which are carbon fiber and polymeric matrix.The aim of this study is to improve the surface properties of the carbon fiber using ionizing radiation from an electron beam to obtain better adhesion properties in the resultant composite.EB radiation was applied on the carbon fiber itself before preparing test specimens for the mechanical tests.Experimental results showed that EB irradiation improved the ten- sile strength of carbon fiber samples.The maximum value in tensile strength was reached using doses of about 250 kGy.After breakage,the morphology aspect of the tensile specimens prepared with irradiated and non-irradiated car- bon fibers were evaluated.SEM micrographs showed modifications on the carbon fiber surface.  相似文献   

18.
This paper describes the magnetic field measurement system for pulsed magnets in SSRF.The system consists of magnetic probes,analog active integrator,oscilloscope,stepper motor and a controller.An application pro- gram based on LabVIEW has been developed as main control unit.After the magnetic field mapping of a septum magnet prototype,it is verified that the test results accord with the results of theoretical calculation and computer simulation.  相似文献   

19.
闭式布雷顿循环是第4代高温堆核能系统的关键技术之一,其典型的动态过程是旁路阀调节。为分析这一过程,建立了循环中关键部件的动态模型,其中压气机在径向平衡模型基础上耦合了对附面层发展的预测,兼顾了计算效率与准确性;换热部件模型基于双曲型守恒律方程,对工质的热物性和参数的快速变化有较好的适应性。在此基础上根据回路的质量守恒和压力平衡原则将各部件的模型耦合,建立了系统的动态模型。由于旁路阀调节是氦气透平发电系统主要的功率快速调节手段,瞬态效应较为显著,以模块式高温气冷堆(HTR-10GT)旁路阀开启后的过渡过程作为算例,分析了主要循环参数的响应特性,并通过分析,给出了降低输出功率的机制。计算结果表明:系统的容积惯性对旁路阀调节的响应速度影响较大,而阀门的开度则决定了系统在末态的输出功率;回热器的温度冲击现象可能发生在调节过程中,但可通过两旁路阀联动的方式缓解;反应堆出口温度变化幅度很小,因此反应堆模型的准确程度对结果基本无影响。  相似文献   

20.
中国实验快堆(CEFR)首次100%额定功率发电运行中,实际电功率较设计值相差较多。为判断影响机组实际发电能力的主要原因,以现场采集的运行数据和汽轮机厂商提供的设计资料为基础,进行了相应的计算分析。对汽轮机内效率进行修正,绘制汽轮机近似热力过程曲线,并通过实测的各段抽汽压力,在热力过程曲线上获得抽汽焓值;利用换热器的能量守恒和流量守恒的基本方程进行除氧器和各加热器的热平衡计算,获得各段抽汽的流量;利用汽轮机的功率计算方程,得到汽轮机发电功率的计算值。通过计算值与实际值的比较分析,得出主蒸汽参数不达标是影响CEFR汽轮机发电能力的主要因素。  相似文献   

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