SPECT在缺血性脑血管疾病中的临床应用

应用＾９９Ｔｃ－ＥＣＤ对３２９例缺血性脑血管病患者进行ＳＰＥＣＴ检查（其中脑梗塞１６０例，脑动脉硬化１２０例，椎基底动脉供血不足３０例，短暂性脑缺血发作（ＴＩＡ）１９例），并将部分病例的ＳＰＥＣＴ结果与Ｘ组ＣＴ作比较，脑梗塞、脑动脉硬化、椎基底动脉供血不足、ＴＩＡ ＳＰＥＣＴ阳性率分别为９０．６％、８９．２％、８６．７％及８４．２％。３２９例中ＳＰＥＣＴ阳性者２９４例，总阳性率为８９．４％，而Ｘ线     

SPECT显像对小儿脑梗塞的研究

为了探讨ＳＰＥＣＴ对小儿脑梗塞（ＣＣＩ）的诊断价值，对２６例患儿采用ＳＰＥＣＴ局部脑血流灌注（ｒＣＰ）显像与ＣＴ对比研究，结果表明，脑梗塞灶及远隔区域的ｒＣＰ减少，ＳＰＥＣＴ和ＣＴ的阳性率分别为９２．３％（２４／２６）和８４．５％（２２／２６），两者无显著性差异（Ｐ〉０．０５），而发病２天以内９例的ＳＰＥＣＴ阳性率１００％（９／９）显著高于ＣＴ５５．６％（５／９）（Ｐ〈０．０５），提示ＳＰＥＣＴ显     

脑SPECT在癫痫儿童中的应用

对１５例儿童癫痫进行发作间期ＳＰＥＣＴ脑局部血流显像，部分患者同时进行了ＥＥＧ、ＣＴ、ＭＲＩ检查。结果显示ＳＰＥＣＴ阳性率最高，ＥＥＧ次之，ＣＴ、ＭＲＩ检出率的低于前二者，表明ＳＰＥＣＴ脑血流显像是诊断儿童癫痫灶的有效方法，且对癫痫儿童的预后，局部脑血流变化与临床表现的演变之间关系等研究有帮助。     

SPECT脑血流灌注显像应用于脑血管疾病

７０例脑血管疾病患者（脑梗塞、ＴＩＡ、ＶＢＩ）行＾９９ｍＴｃ－ＥＣＤ ＳＰＥＣＴ脑血流灌注显像，并与ＣＴ、ＭＲＩ对照，结果ＳＥＰＣＴ诊断脑血管病的阳性率为９０％。ＣＴ为８８．２％（４５／５１），ＭＲＩ为９０％（２７／３１）。脑梗塞５５例中５１例ｒＣＢＦ图像上出现血流灌注减低区，４例发现交叉性小脑神经机能失联络证。诊断ＴＩＡ、ＶＢＩ的阳性率为７５％。ＳＰＥＣＴｒＣＢＦ显像发现病灶较ＣＴ、ＭＲＩ多；可     

轫致辐射显像的初步探讨

应用Ｓｏｐｈｙ ＤＳＸ ＳＰＥＣＴ系统，以＾９０Ｙ、＾３２Ｐ纯β类核素作为辐射源，通过模型实验选用不同准直器、不同能量窗宽等进行轫致辐射显像，以探讨最佳显像条件。结果发现：轫致辐射光谱是连续的，最大光子分布约在７０ｋｅＶ，以高能准直器，取８０ｋｅＶ６０％的能量范围及窗宽或经验性窗宽、且准直器与放射源之间距离较短时图像最为满意，２例病人的显像效果良好。结果表明ＳＰＥＣＴ可以用作轫致辐射显像。     

B超CT和核素显像对甲状腺结节诊断的实验性研究

通过甲状腺结节模型模拟实验研究评价Ｂ超，ＣＴ，核素显像对甲状腺结节诊断的价值，结果显示，Ｂ超，ＣＴ和核素显像的结节点检出率分别为９０％，９１．４％，８４．８％，准确率分别为９２％，１００％，１００％，但Ｂ超有７．６％的误检率，核素显像中，针孔准直器无论是平面还是断层显像均优于平行孔准直器，尤其是对小结节（≤５ｍｍ）的诊断针孔断层提高小结节的检出率。     

SPECT显像在神经疾患中应用的意义和评价

对１５８例（急性脑血管病８４例，癫痫５０例，脑肿瘤１２例，偏头痛７例，震颤麻痹５例）常见脑部疾患进行了ＳＰＥＣＴ脑血流显像，其结果与ＣＴ比较，表明ＳＰＥＣＴ对脑梗塞和ＴＩＡ的早期诊断优于ＣＴ，但ＣＴ对急性脑血管病的定位和定性诊断优于ＳＰＥＣＴ。ＳＰＥＣＴ对癫痫的诊断具有独特的价值，但对脑肿瘤和震颤麻痹的诊断无肯定的价值。     

食品和环境中^90Sr的快速分析

对于￣（９０）Ｓｒ￣（９０）Ｙ处于平衡的样品，用１００％ＴＢＰ萃取￣（９０）Ｙ，Ｃ＿２Ｈ＿５ＯＨ－ＮＨ＿４ＯＨ沉淀反萃，再以Ｙ＿２（Ｃ＿２Ｏ＿４）＿３沉淀制源，在低本底β计数器上测量，以此快速分析食品和环境样品中￣（９０）Ｓｒ的含量。方法对￣（１３７）Ｃｓ、￣（６０）Ｃｏ、￣（１４４）Ｃｅ和￣（１４７）Ｐｍ的去污系数均大于１０￣３。全流程回收率大于７０％。干草和奶粉以及土壤的最小探测限分别为０．２和２Ｂｑ·ｋｇ￣（－１）。分析４个样品在８ｈ内完成。ＩＡＥＡ标准物质的分析结果均处在其标准值范围之内。     

SPECT质量保证现状分析

ＳＰＥＣＴ质量控制和质量保证是保证ＳＰＥＣＴ图像质量的重要内容，通过对广东省ＳＰＥＣＴ质控网断层分辨率模型测试情况及结果分析，讨论ＳＰＥＣＴ质量保证现状及各种采集和重建条件的选择。     

SPECT评价体外反搏治疗缺血性脑血管病

２２例经临床及实验室检查诊断为缺血性脑血客病患者在体外反搏治疗前后用＾９９ｍＴｃ－双胱乙酯行ＳＰＥＣＴ局部脑血流断层显像。治疗前显示ｒＣＢＦ缺血改变５４处，治疗后明显改善的２０处，占３７．０％．部分改善１９处，占３５．２％，无效１５处，占２７．８％，总有效率为７２．２％。结果表明，ＳＰＥＣＴ可用于缺血性脑血管病的早期诊断，还可用以评价缺血性脑血管病的疗效。     

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.