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麦棉套作系统生理学特性研究 被引量:6
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作者 王志芬 陈学留 +4 位作者 余美炎 张凤云 王同燕 陈跃 张贡献 《山东农业科学》 1998年第2期7-12,共6页
在大田条件下利用同位素示踪技术对麦棉套作系统的生理学特性进行了研究。结果表明,麦棉套作系统的生长发育表现出两头强(小麦抽穗前长势强,棉花吐絮期贪青晚熟),中间弱(共生期内小麦早衰、棉苗长势弱)的特点;小麦生育后期(抽... 在大田条件下利用同位素示踪技术对麦棉套作系统的生理学特性进行了研究。结果表明,麦棉套作系统的生长发育表现出两头强(小麦抽穗前长势强,棉花吐絮期贪青晚熟),中间弱(共生期内小麦早衰、棉苗长势弱)的特点;小麦生育后期(抽穗后)特别是在灌浆后期群体根系活力明显降低,穗内32P矿质分配比率减少,茎叶的代谢活力下降;套作棉花在蕾铃期群体根系活力降低,且根系活力高值期出现的时间后延15~25天,高值持续期明显缩短。生殖器官内32P矿质分配比率,从蕾期一直到吐絮期也不同程度的相对降低。但麦棉套作经济效益比单作棉花增加178%以上,本文根据研究结果提出了栽培技术建议。 展开更多
关键词 麦棉套作 群体根系活性 生理学特性
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Positron-emission tomography for hepatocellular carcinoma:Current status and future prospects 被引量:6
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作者 Ren-Cai Lu Bo She +4 位作者 Wen-Tao Gao Yun-Hai Ji Dong-Dong Xu Quan-Shi Wang Shao-Bo Wang 《World Journal of Gastroenterology》 SCIE CAS 2019年第32期4682-4695,共14页
Hepatocellular carcinoma(HCC)is one of the leading causes of cancer mortality worldwide.Various imaging modalities provide important information about HCC for its clinical management.Since positron-emission tomography... Hepatocellular carcinoma(HCC)is one of the leading causes of cancer mortality worldwide.Various imaging modalities provide important information about HCC for its clinical management.Since positron-emission tomography(PET)or PET-computed tomography was introduced to the oncologic setting,it has played crucial roles in detecting,distinguishing,accurately staging,and evaluating local,residual,and recurrent HCC.PET imaging visualizes tissue metabolic information that is closely associated with treatment.Dynamic PET imaging and dual-tracer have emerged as complementary techniques that aid in various aspects of HCC diagnosis.The advent of new radiotracers and the development of immuno-PET and PET-magnetic resonance imaging have improved the ability to detect lesions and have made great progress in treatment surveillance.The current PET diagnostic capabilities for HCC and the supplementary techniques are reviewed herein. 展开更多
关键词 HEPATOCELLULAR CARCINOMA Positron-emission TOMOGRAPHY radiotracer Immuno-positron EMISSION TOMOGRAPHY
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用~75Se对土壤-小麦系统中硒转移规律研究 被引量:7
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作者 李书鼎 曾建华 《生态学报》 CAS CSCD 北大核心 1990年第3期220-225,共6页
本文采用~75Se_2O作示踪剂,通过盆栽试验,对暗棕色森林土-小麦系统中,硒从土壤向小麦籽实的运转问题进行了初步探讨。硒转移规律的研究为合理使用微量元素硒肥,提高小麦中硒含量,从而提高人对硒的摄入量,防治某些地方病提供了理论依据。
关键词 土壤小麦系统 硒转移
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前哨淋巴结示踪剂^(99)Tc^m-IT-Rituximab的制备及初步动物实验研究 被引量:5
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作者 王雪鹃 王荣福 +4 位作者 杨志 林保和 徐冰 张岩 张梅颖 《中国医学影像技术》 CSCD 北大核心 2006年第1期139-143,共5页
目的研究新型特异性前哨淋巴结(SLN)示踪剂^(99)Tc^m-IT-Rituximab的定位效应。方法采用2-亚氨基噻吩(2-IT)修饰法制备^(99)Tc^m-IT-Rituximab,并评价其定位SLN的生物性能,监测注射显像剂的化学剂量及注射体积对SLN摄取的影响。结果^(99... 目的研究新型特异性前哨淋巴结(SLN)示踪剂^(99)Tc^m-IT-Rituximab的定位效应。方法采用2-亚氨基噻吩(2-IT)修饰法制备^(99)Tc^m-IT-Rituximab,并评价其定位SLN的生物性能,监测注射显像剂的化学剂量及注射体积对SLN摄取的影响。结果^(99)Tc^m-IT-Rituximab标记率大于90%,分子保持完整。^(99)Tc^m-IT-Rituximab可清晰定位小鼠SLN,注射后30min到24h SLN均可显影,未见次级淋巴结显影。注药后24h SLNID%值为4.49%,次级及第三级淋巴结ID%摄取率比值相当于本底,24h注射点滞留率为22.14%。示踪剂的化学量及注射体积均影响SLN显像。随着二者的增加,SLN%ID值逐渐减少,次级及第三级淋巴结%ID值均逐渐上升。结论^(99)Tc^m-IT-Rituximab的标记方法简单,研究结果表明其具有潜在的临床应用价值。 展开更多
关键词 前哨淋巴结 示踪剂 99^Tc^m-IT-Rituximab 淋巴显像
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中枢多巴胺系统正电子发射计算机断层扫描显像剂的研究进展
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作者 张格 杨文江 刘宇 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期54-70,共17页
中枢多巴胺系统与多种神经行为障碍的病理生理学有关。一直以来,多巴胺系统正电子发射计算机断层扫描(PET)成像在研究活体大脑中多巴胺生物化学过程上有着重要价值。PET成像的基础是^(11)C、^(18)F等发射正电子的放射性核素标记的显像剂... 中枢多巴胺系统与多种神经行为障碍的病理生理学有关。一直以来,多巴胺系统正电子发射计算机断层扫描(PET)成像在研究活体大脑中多巴胺生物化学过程上有着重要价值。PET成像的基础是^(11)C、^(18)F等发射正电子的放射性核素标记的显像剂,这些显像剂通过与多巴胺神经系统不同的靶点特异性结合从而反映多巴胺合成、囊泡储存、突触释放和受体结合以及再摄取过程,推动神经病学、精神病学、药物滥用和成瘾以及药物开发的研究进展。本文综述了以氨基酸脱羧酶、多巴胺转运体、多巴胺受体以及囊泡单胺转运体为靶点的^(11)C、^(18)F标记的PET显像剂的研究进展。 展开更多
关键词 正电子发射计算机断层扫描 放射性显像剂 多巴胺系统 多巴胺受体 转运体
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承压含水层中放射性示踪剂的非常规径向弥散机理
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作者 吴曾 陈刚 +1 位作者 曹孟雄 胡成 《安全与环境工程》 CAS CSCD 北大核心 2024年第3期247-253,共7页
采用放射性示踪剂评价承压含水层对污染的敏感性和再现污染物补给历史时,示踪剂在承压含水层中的迁移机理尤为重要。采用两区模型建立考虑混合效应的径向弥散数学模型来研究放射性示踪剂在承压含水层中的非常规径向弥散机理,采用拉普拉... 采用放射性示踪剂评价承压含水层对污染的敏感性和再现污染物补给历史时,示踪剂在承压含水层中的迁移机理尤为重要。采用两区模型建立考虑混合效应的径向弥散数学模型来研究放射性示踪剂在承压含水层中的非常规径向弥散机理,采用拉普拉斯变换法推导模型的解析解,采用Stehfest法实现拉普拉斯数值逆变换;为了检验模型中假定条件的精度,利用COMSOL软件建立有限元数值模型进行模拟验证。结果表明:①混合效应越明显时,放射性示踪剂在井筒中的浓度越低;②放射性示踪剂的衰变常数越大,其在承压含水层中的迁移越缓慢;③当质量传输速率小于0.001 a^(-1)时,可以忽略非常规径向弥散对放射性示踪剂的影响,反之,质量传输速率越大,放射性示踪剂在承压含水层中的浓度越低。 展开更多
关键词 放射性示踪剂 非常规径向弥散 解析解 数值模拟
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放射性同位素碳-14标记氯虫苯甲酰胺的合成与分析 被引量:6
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作者 杨征敏 宋明钰 +5 位作者 陈沪飞 余志扬 周迪 夏燕婷 郑东敏 薛晓娅 《农药学学报》 CAS CSCD 北大核心 2020年第1期19-26,共8页
以[14C]碳酸钡为放射性同位素原料,通过格氏反应、亲核取代、胺化和缩合等8步放化反应制备了2种放射性同位素碳-14标记的氯虫苯甲酰胺粗品,经反相高效液相色谱(RPHPLC)纯化获得标记物纯品14C-氯虫苯甲酰胺[3-溴-N-[4-氯-2-甲基-6-(甲氨... 以[14C]碳酸钡为放射性同位素原料,通过格氏反应、亲核取代、胺化和缩合等8步放化反应制备了2种放射性同位素碳-14标记的氯虫苯甲酰胺粗品,经反相高效液相色谱(RPHPLC)纯化获得标记物纯品14C-氯虫苯甲酰胺[3-溴-N-[4-氯-2-甲基-6-(甲氨基[羰基-14C]甲酰基)苯基]-1-(3-氯-2-吡啶基)-1H-吡唑-5-甲酰胺(2,55.6 mCi)和3-溴-N-[4-氯-2-甲基-6-(甲氨基甲酰基)苯基]-1-(3-氯-2-吡啶基)-1H-吡唑-5-[羰基-14C]甲酰胺(3,58.6 mCi)]。以[14C]碳酸钡计,两种标记物的总放化收率分别为32%和52%。其结构经核磁共振氢谱、质谱和在线放射性高效液相色谱(HPLC-FSA)分析确认。放射性薄层成像分析(TLC-IIA)、离线放射性高效液相色谱分析(HPLC-LSC)、在线放射性高效液相色谱-二极管阵列检测器/质谱联用(HPLCFSA/PDA/MS)和LSC分析表明,两种14C-氯虫苯甲酰胺的放化纯度分别为99.8%和99.6%,化学纯度分别为99.1%和98.4%,比活度分别为52.45 mCi/mmol和52.30 mCi/mmol。这2种标记物可作为放射性示踪剂,可满足氯虫苯甲酰胺在中国的登记代谢试验研究的需要。 展开更多
关键词 杀虫剂 同位素标记合成 碳-14 氯虫苯甲酰胺 放射性示踪剂
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Development of ^(18)F-labeled radiotracers for neuroreceptor imaging with positron emission tomography 被引量:3
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作者 Peter Brust Jrg van den Hoff Jrg Steinbach 《Neuroscience Bulletin》 SCIE CAS CSCD 2014年第5期777-811,共35页
Positron emission tomography (PET) is an in vivo molecular imaging tool which is widely used in nuclear medicine for early diagnosis and treatment follow-up of many brain diseases. PET uses biomolecules as probes wh... Positron emission tomography (PET) is an in vivo molecular imaging tool which is widely used in nuclear medicine for early diagnosis and treatment follow-up of many brain diseases. PET uses biomolecules as probes which are labeled with radionuclides of short half-lives, synthesized prior to the imaging studies. These probes are called radiotracers. Fluorine-18 is a radionuclide routinely used in the radiolabeling of neuroreceptor ligands for PET because of its favorable half-life of 109.8 min. The delivery of such radiotracers into the brain provides images of transport, metabolic, and neurotransmission processes on the molecular level. After a short introduction into the principles of PET, this review mainly focuses on the strategy of radiotracer development bridging from basic science to biomedical application. Successful radiotracer design as described here provides molecular probes which not only are useful for imaging of human brain diseases, but also allow molecular neuroreceptor imaging studies in various small-animal models of disease, including genetically- engineered animals. Furthermore, they provide a powerful tool for in vivo pharmacology during the process of pre-clinical drug development to identify new drug targets, to investigate pathophysiology, to discover potential drug candidates, and to evaluate the pharmacokinetics and pharmacodynamics of drugs in vivo. 展开更多
关键词 Alzheimer's disease AUTORADIOGRAPHY blood-brain barrier brain tumor cholinergic system kinetic modeling metabolism molecular imaging NEURODEGENERATION positron emission tomography PRECURSOR psychiatric disorder radiotracer sigma receptor
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多核素PET显像在脑胶质瘤术前分级中的应用进展 被引量:5
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作者 胡裕效 朱虹 卢光明 《医学研究生学报》 CAS 北大核心 2013年第2期190-194,共5页
脑胶质瘤是颅内最常见的恶性肿瘤。对恶性程度不同的脑胶质瘤须采用不同的治疗方法。病理学检查是区分不同级别脑胶质瘤的金标准,但只能以术后标本作为检查材料。18氟-脱氧葡萄糖(18F-fluorodexoxyglucose,18F-FDG PET)显像现已广泛应... 脑胶质瘤是颅内最常见的恶性肿瘤。对恶性程度不同的脑胶质瘤须采用不同的治疗方法。病理学检查是区分不同级别脑胶质瘤的金标准,但只能以术后标本作为检查材料。18氟-脱氧葡萄糖(18F-fluorodexoxyglucose,18F-FDG PET)显像现已广泛应用于恶性肿瘤的诊断,现在认为是术前对脑胶质瘤进行分级诊断的有效方法之一。由于18F-FDG PET/CT显像只能反映肿瘤的葡萄糖代谢情况,该法存在一定的局限性。目前,若干新型的正电子示踪剂可以反映肿瘤的胆碱、氨基酸、脂类物质代谢及肿瘤细胞的增殖状况,对脑胶质瘤的分级诊断有较大帮助。文中介绍近年来18F-FDG等多核素PET显像在脑胶质瘤术前分级诊断中的应用进展。 展开更多
关键词 胶质瘤 分级 放射性示踪剂 正电子发射断层显像
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高比活度碳-14标记毒氟磷的合成与分析 被引量:5
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作者 许亚军 张贵华 +4 位作者 杨征敏 周兵 徐鹏飞 陈沪飞 叶庆富 《农药学学报》 CAS CSCD 北大核心 2017年第6期672-678,共7页
以[^(14)C]碳酸钡为放射性同位素原料,通过格氏反应、Curtius重排、亲核加成、硫代及关环等7步反应,制备了同位素碳-14标记的毒氟磷粗品,经反相高效液相色谱(RP-HPLC)纯化获得标记物纯品^(14)C-毒氟磷(N-[2-(4-甲基苯并[2-^(14)C]噻唑基... 以[^(14)C]碳酸钡为放射性同位素原料,通过格氏反应、Curtius重排、亲核加成、硫代及关环等7步反应,制备了同位素碳-14标记的毒氟磷粗品,经反相高效液相色谱(RP-HPLC)纯化获得标记物纯品^(14)C-毒氟磷(N-[2-(4-甲基苯并[2-^(14)C]噻唑基)]-2-氨基-2-氟代苯基-O,O-二乙基甲基膦酸酯,38.3 m Ci)。7步反应的化学收率/放化收率为10%。其结构经核磁共振氢谱、质谱和放射性高效液相色谱(HPLC-FSA)分析确认。放射性薄层成像分析(TLC-IIA)、高效液相色谱-液体闪烁测量联用分析(HPLC-LSC)、高效液相色谱-流动液体闪烁测量/二极管阵列检测器/质谱联用分析(HPLC-FSA/PDA/MS)和LSC分析表明,^(14)C-毒氟磷的放化纯度和化学纯度均大于98%,比活度为58.0 m Ci/mmol,可作为放射性示踪剂,用于毒氟磷的代谢和环境行为等研究。 展开更多
关键词 同位素标记合成 毒氟磷 碳-14 放射性示踪剂 植物抗病毒剂
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Applications of radiotracer techniques for the pharmacology and toxicology studies of nanomaterials 被引量:4
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作者 ZHANG ZhiYong ZHAO YuLiang CHAI ZhiFang 《Chinese Science Bulletin》 SCIE EI CAS 2009年第2期173-182,共10页
With the rapid development of nanosciences and nanotechnology, a wide variety of manufactured nanomaterials are now used in commodities, pharmaceutics, cosmetics, biomedical products, and industries. While nanomateria... With the rapid development of nanosciences and nanotechnology, a wide variety of manufactured nanomaterials are now used in commodities, pharmaceutics, cosmetics, biomedical products, and industries. While nanomaterials possess more novel and unique physicochemical properties than bulk materials, they also have an unpredictable impact on human health. In the pharmacology and toxicology studies of nanomaterials, it is essential to know the basic behavior in vivo, i.e. absorption, distribution, metabolism, and excretion (ADME) of these newly designed materials. Radiotracer techniques are especially well suited to such studies and have got the chance to demonstrate their enchantment. In this paper, radiolabeling methods for carbon nanomaterials, metallic and metal oxide nanoparticles, etc. are summarized and the applications of the radiolabeled nanomaterials in pharmacology and toxicology studies are outlined. 展开更多
关键词 放射性示踪剂 毒物学 药理学 数量分析
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放射性同位素示踪在泥沙研究中的应用 被引量:4
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作者 陈月红 刘孝盈 汪岗 《水利水电技术》 CSCD 北大核心 2003年第5期4-6,共3页
介绍了放射性同位素作为示踪物应用在泥沙运动研究中的情况,特别是国外广泛使用的同位素,如113In铟,198Au金,51Cr铬,192Ir铱,46Sc钪,110Ag银等及其示踪的物理形式,和在悬移质、推移质研究对同位素颗粒大小的选择,描述了如何准备放射性... 介绍了放射性同位素作为示踪物应用在泥沙运动研究中的情况,特别是国外广泛使用的同位素,如113In铟,198Au金,51Cr铬,192Ir铱,46Sc钪,110Ag银等及其示踪的物理形式,和在悬移质、推移质研究对同位素颗粒大小的选择,描述了如何准备放射性同位素物质以及注入、示踪和数据收集等等.另外还介绍了在印度Madras港开展放射性同位素示踪疏浚泥沙运动研究的实例.最后,分析评述了国内利用放射性同位素示踪研究的进展情况. 展开更多
关键词 放射性同位素 泥沙运动 悬移质 推移质 疏浚
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两种放射性同位素碳-14标记毒氟磷的合成与分析 被引量:4
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作者 杨征敏 见才广 +10 位作者 周兵 许亚军 张贵华 徐凌峰 李霄 唐胜华 徐鹏飞 陈沪飞 夏燕婷 李少博 叶庆富 《有机化学》 SCIE CAS CSCD 北大核心 2018年第5期1177-1184,共8页
以[^(14)C]碳酸钡为放射性同位素原料,通过乙炔环三聚、苯羧基化和甲基化、胺化、环化、亲核取代、格氏、还原、氧化等反应和反相高效液相色谱(HPLC)纯化获得了2种放射性同位素碳-14标记毒氟磷[N-[2-(4-甲基[苯基-U-^(14)C_6]苯并噻唑基... 以[^(14)C]碳酸钡为放射性同位素原料,通过乙炔环三聚、苯羧基化和甲基化、胺化、环化、亲核取代、格氏、还原、氧化等反应和反相高效液相色谱(HPLC)纯化获得了2种放射性同位素碳-14标记毒氟磷[N-[2-(4-甲基[苯基-U-^(14)C_6]苯并噻唑基)]-2-氨基-2-氟苯基-O,O-二乙基甲基膦酸酯(2,20.6 m Ci)和N-[2-(4-甲基苯并噻唑基)]-2-氨基-2-氟苯基-O,O-二乙基[^(14)C]甲基膦酸酯(3,32.4 m Ci)],其结构经核磁共振氢谱(~1H NMR)和在线放射性高效液相色谱-二极管阵列检测器/质谱联用(HPLC-FSA/PDA/MS)分析确认,反应总放化收率/化学收率分别为31%和67%.放射性薄层层析-同位素成像分析(TLC-IIA)、离线放射性高效液相色谱(HPLC-LSC),HPLC-FSA/PDA/MS和液体闪烁测量(LSC)分析表明,两种标记物的放化纯度和化学纯度均大于98%,比活度分别为25.5,55.5 m Ci/mmol.该标记物可作为放射性示踪剂,用于毒氟磷的代谢、残留和环境行为等研究. 展开更多
关键词 同位素标记合成 毒氟磷 碳-14 放射性示踪剂 植物抗病毒剂
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Difluorocarbene-derived rapid late-stage trifluoromethylation of 5-iodotriazoles for the synthesis of^(18)F-labeled radiotracers
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作者 Fang Yuan Hongbao Sun +8 位作者 Cheng Yang Haojie Yang Lili Pan Xiaoyang Zhang Rong Tian Lingjun Li Wei Chen Xiaoai Wu Haoxing Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第6期336-340,共5页
Difluorocarbene has emerged as a valuable intermediate to synthesize fluorides.However,difluorocarbene-derived synthesis of^(19)F/^(18)F-trifluoromethyl triazoles has not been explored.Herein,we reported the Cu(I)-pro... Difluorocarbene has emerged as a valuable intermediate to synthesize fluorides.However,difluorocarbene-derived synthesis of^(19)F/^(18)F-trifluoromethyl triazoles has not been explored.Herein,we reported the Cu(I)-promoted difluorocarbene-derived^(19)F/^(18)F-trifluoromethylation of iodotriazoles using KF/K^(18)F as the fluorine source.This approach rapidly generated a wide range of 5-trifluoromethyl-1,2,3-triazoles in good yields showing high functional group compatibility.The reaction was effective for late-stage functionalization of bioactive molecules and^(18)F-trifluoromethylation of iodotriazoles.This work provides a practical synthetic methodology for the development of triazole drugs and^(18)F-radiotracers for positron emission tomography. 展开更多
关键词 DIFLUOROCARBENE TRIFLUOROMETHYLATION TRIAZOLE Late-stage functionalization ^(18)F-Labeled radiotracer
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Tumor targeting of HPMA copolymer conjugates containing sulfadiazine groups 被引量:1
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作者 Jian Chao Yuan Xiao Li Xie +2 位作者 Xian Wu Zeng Hong Yun Guo Cheng Ping Miao 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第7期875-878,共4页
To develop new tumor targeting macromolecular conjugates,poly(HPMA)-SD-APMA-DTPA(HPMA:N-(2-hydroxypropyl)- methacrylamide;APMA:N-(3-ammopropyl)methacrylamide;DTPA:diethylenetriaminepentaacetic acid;SD:sulfa... To develop new tumor targeting macromolecular conjugates,poly(HPMA)-SD-APMA-DTPA(HPMA:N-(2-hydroxypropyl)- methacrylamide;APMA:N-(3-ammopropyl)methacrylamide;DTPA:diethylenetriaminepentaacetic acid;SD:sulfadiazine) was synthesized and characterized.The poly(HPMA)-SD-DTPA conjugates were radiolabeled with the radionuclide ^(99m)Tc and tested for uptake by cultured H22 cells in vitro.DTPA-^(99m)Tc(radiotracer 1) and poly(HPMA)-DTPA-^(99m)Tc(radiotracer 2) were also synthesized and characterized for comparison.The uptake of poly(HPMA)-SD-DTPA-^(99m)Tc(radiotracer 3,34.76%) was significantly higher than that of poly(HPMA)-DTPA-^(99m)Tc(16.40%),indicating that uptake of the poly(HPMA)-SD-DTPA-^(99m)T was active binding.The uptake of poly(HPMA)-DTPA-^(99m)Tc was significantly higher than that of DTPA-^(99m)Tc(2.98%), suggesting that uptake of the poly(HPMA)-DTPA-^(99m)T was passive binding.The data suggest that the poly(HPMA)-SDAPMA -DTPA conjugates might be useful as tumor targeting macromolecular conjugates. 展开更多
关键词 Tumor targeting HepatoceUular carcinoma HPMA copolymer conjugates radiotracer
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阿尔茨海默病PET正电子药物应用与研究进展 被引量:3
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作者 段小艺 李淼 +3 位作者 王黎 李宏利 赵周社 郭佑民 《国际放射医学核医学杂志》 2014年第5期318-322,共5页
阿尔茨海默病(AD)严重危害人们的身心健康。伴随PET分子成像的发展,出现了一系列针对AD的正电子药物,其中匹兹堡化合物B(PIB)及其衍生物类PET正电子药物研究最为成熟,部分已获准应用于临床,在AD诊断与治疗方面显示出重要价值。... 阿尔茨海默病(AD)严重危害人们的身心健康。伴随PET分子成像的发展,出现了一系列针对AD的正电子药物,其中匹兹堡化合物B(PIB)及其衍生物类PET正电子药物研究最为成熟,部分已获准应用于临床,在AD诊断与治疗方面显示出重要价值。随着人们对AD发生机制研究的不断深入,近年又相继出现了包括蛋白类、受体类以及肽类在内的更多种类AD相关PET正电子药物。该文就此类正电子药物的应用与研究进展做一综述。 展开更多
关键词 阿尔茨海默病 正电子发射断层显像术 正电子药物
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放射性同位素碳-14标记毒死蜱的合成与分析 被引量:3
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作者 余凯翔 杨征敏 +4 位作者 周兵 徐凌锋 李书琰 陈沪飞 王伟 《同位素》 CAS 2020年第6期409-416,共8页
以[14C]碳酸钡为放射性同位素原料,通过格氏反应、亲核取代、分子内环化反应、脱水芳构化、亲电氯代等9步放化反应和反相高效液相色谱(RP-HPLC)制备获得14C-毒死蜱(1,O,O-二乙基-O-(3,5,6-三氯-2-[2,6-14C]吡啶基)硫代磷酸酯,30.2 mCi)... 以[14C]碳酸钡为放射性同位素原料,通过格氏反应、亲核取代、分子内环化反应、脱水芳构化、亲电氯代等9步放化反应和反相高效液相色谱(RP-HPLC)制备获得14C-毒死蜱(1,O,O-二乙基-O-(3,5,6-三氯-2-[2,6-14C]吡啶基)硫代磷酸酯,30.2 mCi)。以[14C]碳酸钡计,9步合成反应的总收率为11%。目标物14C-毒死蜱的化学结构经核磁共振氢谱、质谱和在线放射性高效液相色谱(HPLC-FSA)分析确认。放射性薄层成像分析(TLC-IIA)、离线放射性高效液相色谱(HPLC-LSC)、在线放射性高效液相色谱-二极管阵列检测器/质谱联用(HPLC-FSA/PDA/MS)和LSC分析表明,14C-毒死蜱的放化纯度和化学纯度均大于98%,比活度为55.2 mCi/mmol,可作为放射性示踪剂,用于毒死蜱的药代动力学、生态环境安全与污染消减机制等研究。 展开更多
关键词 同位素标记合成 毒死蜱 碳-14 放射性示踪剂 杀虫剂
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Synthesis and Preliminary Evaluation of 1-[^18F]Fluoro-1-deoxy-2,5-anhydro-D-mannitol as a PET Radiotracer for Breast Cancer Imaging
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作者 Ben Niu Xiaoan Wen +3 位作者 Zhijun Jia Xiaoming Wu Wanhua Guo Hongbin Sun 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2013年第9期1159-1163,共5页
1-[^18F]Fluoro-l-deoxy-2,5-anhydro-D-mannitol (3, ^18F-FDAM) has been synthesized in 6 steps starting from 2,5-anhydro-D-mannitol (2,5-AM) and evaluated as a new radiotracer for PET imaging of MCF-7 breast tumor. ... 1-[^18F]Fluoro-l-deoxy-2,5-anhydro-D-mannitol (3, ^18F-FDAM) has been synthesized in 6 steps starting from 2,5-anhydro-D-mannitol (2,5-AM) and evaluated as a new radiotracer for PET imaging of MCF-7 breast tumor. The result of PET imaging study showed that 3 displayed a slightly higher uptake by breast tumor in comparison with the normal breast tissue, implying the possibility of development of PET radiotraeers based on targeting fructose transporters. 展开更多
关键词 PET imaging radiotracer ^18F-FDAM fructose transporter breast cancer
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Radiotracer Investigation of the Effect of Impeller Type on Mixing in Industrial Process Simulator
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作者 Simon Yao Adzaklo Christian Priesley Kofi Dagadu +4 位作者 Ishmael Iddisah Mumuni Patience Adwoa Serwah Adu Hannah Asamoah Affum Godfred Kofi Appiah Alexander Coleman 《Journal of Applied Mathematics and Physics》 2018年第3期468-474,共7页
Radiotracer technology has been applied in industry for the investigation of process performance, online monitoring of conditions of process units, troubleshooting and diagnosing anomalies including mixing conditions ... Radiotracer technology has been applied in industry for the investigation of process performance, online monitoring of conditions of process units, troubleshooting and diagnosing anomalies including mixing conditions in continuous stirred tank reactors. In this study, radiotracer methodology was used to carry out investigation on a laboratory water flow rig which serves as simulator of industrial processes. The aims of the investigation were to assess: i) the effect of impeller type on mixing and ii) the fluid dynamics of the water in the vessels since both the vessels and the impellers were redesigned and reconstructed. Four similar vessels in series circuit with different impeller configurations were investigated. Tank 1 has 1 axial impeller, Tank 2 has 2 axial impellers, Tank 3 has 2 radial impellers and Tank 4 has no impeller. The data were collected by introducing 8 mCi liquid technetium-99 m at the inlet stream of the vessels and the gamma signal was detected with thallium activated NaI detector placed at the outlet of the vessels. Residence Time Distribution (RTD) curves for the outlet tracer concentration were generated from which the Mean Residence Time (MRT) and the variance were calculated by the method of moments. The extent of material mixing in the vessels was inferred from the variances and the fluid dynamics was obtained by modeling. The extent of mixing was highest in Tank 2 followed by Tank 3, and Tank 4 gave the poorest mixing. The outlet response curves were fitted with mathematical models using DTS pro and “RTD Software”. The best fit for Tanks 2, 3 and 4 was Perfect Mixers in Series with Exchange (PMSE) model while Perfect Mixers in Series with Recycle (PMSR) model best described the fluid dynamics of the material in Tank 1. 展开更多
关键词 AXIAL IMPELLERS MIXING RADIAL radiotracer
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Interventional Radionuclide Therapy of Hepatocellular Carcinoma: Assessment of Intratumoral Retention of HPMA Copolymers
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作者 YUAN Jian-chao MIAO Cheng-ping +4 位作者 ZENG Xian-wu GUO Hong-yun WANG Xiao-qi LIAO Shi-qi XIE Xiao-li 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2013年第1期183-188,共6页
To develop new radiopharmaceuticals for the interventional radionuclide therapy of recurrent hepatocellular carcinoma, poly(HPMA)-APMA-DTPA[HPMA=N-(2-hydroxypropyl) methacrylamide; APMA=N-(3-aminopropyl)methacry... To develop new radiopharmaceuticals for the interventional radionuclide therapy of recurrent hepatocellular carcinoma, poly(HPMA)-APMA-DTPA[HPMA=N-(2-hydroxypropyl) methacrylamide; APMA=N-(3-aminopropyl)methacrylamide; DTPA=diethylenetriaminepentaacetic acidl was synthesized by free radical precipitation polymerization in acetone/dimethylsulfoxide with N,N'-azobis(isobutyronitrile) as the initiator. The copolymers were characterized with nuclear magnetic resonance(NMR) spectroscopy and gel permeation chromatography(GPC, Mn=2.2xl04, Mw/Mn=l.38). Subsequently, poly(HPMA)-APMA-DTPA was conjugated with 99mTC radionuclide. Prolonged retention of poly(HPMA)-APMA-DTPA conjugate within the tumor tissues was demonstrated by single-photon emission computed tomography computed tomography(SPECT-CT) at 1, 2, 4 and 24 h following intra-tumoral injection of the conjugate to hepatocellular carcinoma xenografts in mice. DTPA-99mTc was also synthesized and characterized for comparison. The data suggest that the poly(HPMA)-APMA-DTPA conjugates might be useful for the interventional radionuclide therapy of recurrent hepatocellular carcinoma in humans. 展开更多
关键词 Hepatocellular carcinoma Interventional radionuclide therapy HPMA copolymer radiotracer
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