125I-RC-160的标记及与NCI-H446细胞体外受体结合特性的研究

为探索高比活度12 5I -生长抑素类似物 (RC - 160 )的制备及与小细胞肺癌 (SCLC)细胞株-NCI-H4 46体外受体结合特性。12 5I -RC - 160采用氯胺T法标记 ,C18反向色谱柱纯化 ,硅胶纸层析检测。12 5I-RC - 160与NCI -H4 46细胞进行体外结合实验、饱和结合实验和竞争结合实验。12 5I -RC - 160标记率为 5 4.34 % ,比活度 1.85TBq/ (mmol·L- 1) ,放射化学纯度 (RCP)为 92 % ;Scatchard作图提示 ,Kd 为 1.71× 10 - 10 mol/L ,Bmax为 1.0 6× 10 5个 /细胞。制备的12 5I -RC - 160达到体外受体配体结合分析的标准 ;12 5I-RC - 160与NCI -H4 46的结合具有温度时间依赖性、可饱和性、可逆性及特异 ;12 5I -RC - 160与NCI -H4 46细胞生长抑素受体的结合符合单位点系统。     

消脂素的间接碘标记法与直接碘标记法的对比研究

间接碘标记法是先以氯胺T（ch-T）法标记对羟基苯丙酸琥珀酰亚胺脂（Bolton-hunter试剂,BH试剂）,制备125I-BH,然后于冰浴中与LEP联结,得到125I-LEP;直接碘标记法是以ch-T法按常规对LEP直接进行标记。结果显示,间接碘标记法标记的125I-LEP放射性比活度为1．43MBq／μg,125I的总标记率为37．8％,所建立的RIA的灵敏度为0．25μg/L,在45天内标准曲线（0．5-30μg／L）稳定,B：Bo位于92．7％-17．5％到94．6％-22．8％之间。直接法制备的125I-LEP,放射性比活度为1．79MBq／μg,125I的总标记率为41．4％,方法灵敏度为0．37μg/L。在44天内标准曲线（0．5～30μg／L）亦较稳定,B：B0位于87．7％～23．7％到91．4％-35．2％之间。表明两方法的标准曲线稳定性在45天内差异不大,均能满足临床工作的需求。     

Iodogen法~(125)I标记单克隆抗体10D9

采用Iodogen法,选择最佳标记条件进行12525I标记单克隆抗体10D9.标记产物用Sephadex G-50分离纯化,三氯醋酸(TCA)法测定标记率和放化纯,并对标记物的免疫活性及稳定性进行分析.结果显示,125I标记10D9的最佳条件为Iodogen用量10μg、10D9用量20μg、加入Na125I22.2MBq、室温反应8min,125I-10D9的标记率为(84.10±3.18)%,放化纯为(98.49±1.14)%,比活度为933.51 MBq/mg;125I-10D9与Daudi细胞的特异性结合率为(23.21±1.14)%;标记物加到含1%BSA的PBS中放置3W后放化纯度仍>90%.结果表明:Iodogen法125I标记10D9标记率和放化纯高,方法简便,标记物的稳定性好且能较好地保持其免疫活性.     

~(125)I-SOD氯胺T法和Iodogen法标记条件的研究

选用正交设计L_(16)(4~5)表对影响~(125)I-SOD氯胺T标记法的5个影响因素(即标记温度、氯胺T加入量、标记反应时间、PB缓冲溶液的浓度和体积),每个因素分4个水平进行了研究。标记产物~(125)I-SOD用Sephadex G25色层柱进行分离,并测定了标记率和相对活性,仅做16组试验就得出了最佳标记条件。在此基础上又用正交设计L_9(3~4)表对~(125)I-SOD Iodogen固相标记法进行了研究。取Iodogen加入量、标记温度和反应时间3个因素,每个因素3个水平,仅做9组试验,就确定了最佳标记条件:对20μg SOD而言,Iodogen为50μg,标记温度为15℃,反应时间为15min时,~(125)I的标记率可达79.0％,~(125)I-SOD的放化纯度达95.7％,相对活性达98.2％,比活度达2.92×10~5Bq/μg,明显优于氯胺T法。     

~(125)I-SOD氯胺T法和Iodogen法标记条件的研究

选用正交设计L_(16)(4~5)表对影响~(125)I-SOD氯胺T标记法的5个影响因素(即标记温度、氯胺T加入量、标记反应时间、PB缓冲溶液的浓度和体积),每个因素分4个水平进行了研究。标记产物~(125)I-SOD用Sephadex G25色层柱进行分离,并测定了标记率和相对活性,仅做16组试验就得出了最佳标记条件。在此基础上又用正交设计L_9(3~4)表对~(125)I-SOD Iodogen因相标记法进行了研究。取Idosen加入量、标记温度和反应时间3个因素,每个因素3个水平,仅做9组试验,就确定了最佳标记条件:对20μg SOD而言,Iodogen为50μg,标记温度为15℃,反应时间为15min时,~(125)I的标记率可达79.0％,~(125)I-SOD的放化纯度达95.7％,相对活性达98.2％,比活度达2.92×10~5Bq/μg,明显优于氯胺T法。     

抗CEA单克隆抗体碘标记方法研究

本文报道用几种碘标记方法(Iodosen、ChT、NBS、Bolton-Hunter试剂等)制备了~(125)I(~(131)I)-抗CEA单克隆抗体。产品通过Sephacex G-50(或-75)柱凝胶过滤纯化后,经纸层析和高压液相层析法鉴定,其放化纯度达到使用要求;用免疫放射双抗体夹心法测定,标记抗体能保持良好的免疫活性。同时我们对上述几种碘标方法进行比较研究,结果NBS法标记率最高,达98％,Iodogen法免疫活性保持最好,与CEA的净结合数达9960cpm(3ng CEA/250μl)。     

体内标记~(99m)Tc-红细胞

我们为了试制供~(99m)Tc标记红细胞使用的药盒,在兔子体内进行了标记条件的研究。 当使用亚锡-焦磷酸盐,其pH为4.5、用量为0.1—0.2mg/kg体重,静脉注射兔子体内,半小时后再注入高锝酸钠,其比活度可达2.96×10~7-42.18×10~7Bq/ml(0.8—11.4mCi/ml);     

大体积水中钚的浓集和测定

以活性Al2 O3为吸附剂 ,采用吸附型大体积水样采集装置浓集水中钚 ,用HNO3 NaF溶液浸出钚 ,最后分离纯化。在 10 0L自来水中加入 5 0× 10 - 3 Bq/L2 39Pu时 ,全程放化回收率为 :(4 7 6± 8 5 ) % ,10 0L水中2 39Pu的探测下限为 3 0× 10 - 6Bq/L     

EM>N-/EM>琥珀酰亚胺-3-碘［S

研究能有效降低抗体的体内脱碘的标记方法。碘标记N-琥珀酰亚胺-3-(三正丁基锡)苯甲酸酯(ATE)前体,得到N-琥珀酰亚胺-3-碘[125I]苯甲酸酯(S125IB),分别与人IgG和抗人肝癌单抗(Hepama-1)进行偶联,探索最佳标记条件,并测定标记物的稳定性和生物活性,研究直接标记和间接标记的Hepama-1在正常小鼠体内的生物学分布。结果表明,用N-氯代琥珀酰亚胺(NCS)法125I标记ATE前体,在ATE用量为25～100μg、NCS用量为10～20μg、磷酸盐缓冲溶液(PBS)用量为10～20μL、反应时间为5 min时,标记率大于95%;S125IB和人IgG的偶联率最高可达75%,偶联产物稳定性、生物活性良好;与Hepama-1偶联率可达75%以上。生物分布的对比实验证明,1,3,4,6-四氯-3α,6α-二苯甘脲(Iodogen)直接标记的Hepama-1在甲状腺的放射性摄取率(脱碘显示)最高是S125IB间接标记的Hepama-1的87.9倍。这说明以ATE为前体的放射性碘间接标记蛋白质方法与传统的碘直接标记方法相比较,在解决体内严重脱碘问题上具有明显的优越性。     

血管抑素的131I标记及其对裸鼠A549肺肿瘤的作用

采用一步法从人血浆中分离血管抑素(Angiostatin,AS),并用L-Lysine Sepharose 4B作亲和层析纯化;将提纯的AS用Iodogen固相法进行131I标记,分析131I-AS的标记率、比活度,并评价其体外稳定性;32只荷A549肺肿瘤的裸鼠随机分为4组,腹腔注射131I-AS(含11.1 MBq131I,AS为12.5 mg/kg)1、31I 11.1MBq、AS 12.5 mg/kg和生理盐水0.3 mL,1次/周,治疗4周,观察28 d内肿瘤体积的变化。结果显示,131I-AS标记率为77.8%~86.7%,比活度为1.28~3.96 TBq/g,放化纯度为98.6±0.26%。标记产物-20℃存放7 d,放化纯度降至72%;治疗28 d后,131I-AS组1、31I组、AS组和生理盐水组小鼠肿瘤的体积分别是(1 956±98)(、5 284±123)(、3 948±115)(、7 350±153)mm3。以上结果提示,131I-AS能较强地抑制小鼠体内移植肿瘤的生长,其抑制作用优于单纯应用等浓度的AS及131I,131I-AS在治疗肿瘤中有潜在的应用前景。     

Identification of radiation treatment of wheat （Triticum aestivum. L）and rice （Oryza sativa. L） samples using thermoluminescence of contaminating minerals

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.     

Preparation of Zn/TiO2 powder and its photocatalytic performance for oxidation of P-nitrophenol

Zn-doped TiO2 catalysts were prepared using a sol-gel method and characterized by XPS,UV-Vis, BET, XRD in this study. Under the irradiation of simulant sunlight, the photocatalytic activity for the degradation of p-nitrophenol was studied too. After irradiation for 2.5 h, the degradation percentage of p-nitrophenol could rise to more than 80 %. The results showed that the spectrum absorption band edge of Zn/TiO2 powder does not broaden obviously comparing with pure TiO2 powder. Zinc exists as Zn （11）. When calcined at 973 K, there is a new phase as ZnTiO3 in Zn/TiO2 catalyst. The order of photocatalytic activity of Zn/TiO2 catalysts calcined at different temperatures for p-nitrophenol is 773 K 〉 673 K 〉 873 K 〉 573 K 〉 973 K and the photocatalytic activity of Zn/TiO2 catalyst calcined at 773 K is better than TiO2 catalysts heated at the same temperature, and outclasses that of commercial TiO2 catalyst. It also showed that the photocatalytic degradation of p-nitrophenol follows first-order kinetics under the irradiation of simulant sunlight.     

Current status of radiation therapy for prostate cancer

Radiotherapy for the treatment of prostate cancer has been extensively explored in the past. Along with the comprehensive understanding of the biology of prostate cancer and rapid advances in terms of technology, the out- come of treatment for the patients with prostate cancer has improved. The authors review radiotherapy as the primary treatment for the disease, with particular emphasis on the technological advances from both the radiobiological and radiophysics aspects. Nonconventional fractionated irradiation like hyper- or hypo-fractionation has been imple- mented in the clinic, the final results still need to be confirmed in the future. Technological advances like IMRT, IGRT, in the last two decades have significantly improved the delivery of external radiotherapy to the prostate. This has re- sulted in an overall increase in the total dose that can be safely delivered to the prostate, which has led to modest im- provements in the biochemical outcome. However, establishing the standard therapy for prostate cancer remains con- troversial. It is hoped that the next decades will bring continued advances in the development of biologicals that will further improve current clinical outcomes.     

The control system for SSRF injection and extraction

This paper introduces the injection and extraction control system design for SSRF,which is a distributed control system aimed at stability and reliability of the pulse power supplies,PPS(Personnel Protection System)and MPS(Machine Protection System).The hardware environment is mainly based on PLC(Programmable Logic Con- troller),and ARM(Advanced RISC Machine)is also applied for studying stability of the power supplies.WinCC and EPICS(Experimental Physics and Industrial Control System)have been selected as the platforms of SCADA(Super- visory Control and Data Acquisition).For unifying the interfacing to the control computer,all front-end equipments are connected via Industrial Ethemet.     

水平管内含空气蒸汽强制对流冷凝换热模型研究

为研究含空气蒸汽在水平管内强制对流冷凝换热特性,基于对传热传质过程的分析,建立了管内为环状流与波状流条件下的流动冷凝换热模型。从潜热、显热和液膜3个环节对整个换热过程进行建模,最终得到计算局部冷凝换热系数的理论关系式。模型预测结果与实验数据的对比表明,二者相对偏差在±20%以内,验证了该换热模型的准确性与适用性。通过进一步的研究发现：从换热管入口至出口,随着冷凝的进行,管内换热主要热阻由液膜热阻向气液界面的凝结热阻转变;主流气体对流换热过程基本可忽略。     

Web Services interface of SSRF archive data analysis system

Accelerator database stores various static parameters and real-time data of accelerator. SSRF (Shanghai Synchrotron Radiation Facility) adopts relational database to save the data. We developed a data retrieval system based on XML Web Services for accessing the archive data. It includes a bottom layer interface and an interface applicable for accelerator physics. Client samples exemplifying how to consume the interface are given. The users can browse, retrieve and plot data by the client samples. Also, we give a method to test its stability. The test result and performance are described.     

Investigations on landmine detection by BF3 detector

Experiments were carried out to investigate the possible use of neutron backscattering for the detection of polyethylene (PE) sample buried in the soil. In detection of landmine by neutrons, the neutron detector and its shield play an important role. In this paper, the effects of graphite, heavy water, polyethylene and boric acid moderators on the flux of back scattered neutrons were investigated. We have also experimentally verified the effect of BF3 detector shield and obtained good agreement with theory.     

Preparation and properties of 117m Sn(IV)-TTHMP in in-vitro and in small animals

In this work,TTHMP was synthesized and labelled with 117m Sn.The preparation conditions,stability and lipophilicity of 117m Sn(IV)-TTHMP were investigated.Biodistribution of the complex in rabbits and mice was studied.It was found that the quantity of TTHMP and pH value of the prepararion solution had vital effects on the labeling yield of 117m Sn(IV)-TTHMP.It was also found that 117m Sn(IV)-TTHMP was hydrophilic and stable at room temperature and 37℃ in open air 117m Sn(IV)-TTHMP showed unexpectedly high bone uptake and bone-to-blood ratio in the animals.This made it potentially useful as an reagent for skeletal scintigraphy and radiotherapy of bone tumors.     

Assessment of radioactivity levels in some oil samples from the western desert, Egypt

Distributions of natural gamma-emitting radionuclides were determined in 93 oil samples collected from some petroleum fields in the western desert of Egypt. The radioisotope activities in the area under investigation lay in the range of (21 ± 4) to (38 ± 13) Bq?L-1 for 226Ra, (9 ± 2) to (15 ± 5) Bq?L-1 for 232Th, and (154 ± 28) to (303 ± 54) Bq?L-1 for 40K. The mean values were 27, 12, and 201 Bq?L-1, respectively. Among oils, variations in radionuclide ac- tivities could be on account of differences in TDS, HCO3, and Ba, with high or low pH. In this environment, oil prop- erties differently affected the mobilization of natural radionuclides. The range of 226Ra variation had been compared with available data from other countries. The calculated absorbed dose rate ranged from 22.33 to 32.66 nGy?h-1 in lo- cation (B) and (E) respectively, which was less than the accepted value.     

Gamma radiation levels in the ambient environment of the QNPP Base

Monitoring results of gamma dose rate level in 1992～2004 in the ambient environment of the Qinshan Nuclear Power Plants(QNPP)Base,the northeast of Zhejiang Province,are reported in this paper.It is shown that the gamma dose rate of five monitoring sites of 2.5 km to QNPP Base is 84～113 nGy/h,with an average of 96 nGy/h in the 13 years.The average value is close to the background level of 93 nGy/h prior to operation of the QNPP Base,and is lower than the monitoring result of 101 nGy/h at the reference site in Hangzhou City.Within 50 km from the QNPP Base,the cumulative dose rate of the thermoluminescent dosimeter(TLD)is 90 nGy/h,which is lower than the back- ground level of 111 nGy/h.