应用鲁米诺化学发光法测定脂质过氢化

建立了一个测定脂质过氧化（Lipid peroxidation,LPO）的化学发光体系，测试某些抗氧化剂消除脂自由基的活性。取含有不饱和脂肪酸的脂质加入到测量管中，再加入鲁米诺及双重蒸馏水，放入预恒温箱中37℃预温育0.5h，取出并加入启动剂AAPH{2，2’-azobis(2-amjdinopropane)dihydrochloride}，立即放入预先温度设至38-39℃的生化发光测量仪中，用T-2程序测定每6s钟的脉冲数（CP6s），连续测定，观察化学发光（chemiluminescence,CL）的动力学变化和是否产生脂质过氧化，随后加入各类抗氧化剂，根据实际需要，选其某一次的CL强度作为评判指标。建立了一个应用鲁米诺化学发光法测定脂质过氧化的体系并对比了多种抗氧化剂的活性。结果发现，Vit.C、茶多酚（EGCG）、还原型谷胱甘肽（GSH）皆有抑CL，即抗脂质过氧化的作用。该方法是一种快速、灵敏、简便的测定脂质过氧化及筛选抗氧化剂的新方法。     

SIN-1产生ONOO-及其被抗氧化剂清除的化学发光研究

采用3-morpholino-sydnonimine(SIN-1)作为过氧亚硝基(ONOO-)的发生器,以鲁米诺作为光的扩增剂,建立一个检测ONOO-及筛选清除剂的发光体系.在探索pH、温度、SIN-1浓度对ONOO-发光强度影响的基础上,确定了ONOO--鲁米诺化学发光体系,测定了水溶性维生素E(Trolox)、茶多酚、槲皮素对ONOO-的清除作用.建成SIN-1为0.30mg/mL、鲁米诺为1×10-4mol@L-1、pH7.4、温度为30℃的发光体系,测得3种清除剂皆有清除ONOO-的作用,清除效果槲皮素＞茶多酚＞Trolox.SIN-1-鲁米诺化学发光体系测定ONOO-的产生和清除是一个快速、简便、灵敏且较稳定的新技术.     

二甲亚砜和维生素E对照剂小鼠脂质过氧化的影响

二甲亚砜（ＤＭＳＯ）和维生素Ｅ（Ｖｉｔ Ｅ）都是自由基清除剂，可抑制或阻断由自由基引发的脂质过氧化反应，减轻组织损伤和细胞的破坏。本研究应用荧光分光光度法，通过测定小鼠血清中脂质过氧化代谢产物丙二醛（ＭＤＡ）的含量来研究不同浓度的ＤＭＳＯ和维生素Ｅ对γ射线照射后小鼠的保护作用，以及两者联合应用的效果。结果表明：ＤＭＳＯ的保护作用优于Ｖｉｔ Ｅ，最大脂质过氧化抑制率（４．０Ｇｙ）分别为５５．１％和５     

几种制剂对辐射所致脂质过氧化作用的影响

本文报道了γ射线照射对小鼠肝、脾、肾中脂质过氧化物（ＬＰ０）含量的影响，以及照后服用知母宁、单宁酸和鲨烯等制剂的抗脂质过氧化作用。制剂均灌胃给药，ＬＰＯ用改良的ＴＢＡ分光光度法测定。结果表明，γ射线整体照射小鼠后７２ｈ，其组织中ＬＰＯ含量增高，在０－４Ｇｙ范围内辐射剂量与ＬＰＯ含量呈线性关系；三种制剂均有降低小鼠肝、脾、肾中ＬＰＯ的作用，其中知母宁（０．３５ｍｇ／ｄ）的抗脂质过氧化作用显著优于单宁酸（１５ｍｇ／ｄ）和鲨烯（０．６ｍｇ／ｇ）。     

二甲亚砜和维生素E对照射小鼠脂质过氧化的影响

二甲亚砜（ＤＭＳＯ）和维生素Ｅ（ＶｉｔＥ）都是自由基清除剂，可抑制或阻断由自由基引发的脂质过氧化反应，减轻组织损伤和细胞的破坏。本研究应用荧光分光光度法，通过测定小鼠血清中脂质过氧化代谢产物丙二醛（ＭＤＡ）的含量来研究不同浓度的ＤＭＳＯ和维生素Ｅ对γ射线照射后小鼠的保护作用，以及两者联合应用的效果。结果表明：ＤＭＳＯ的保护作用优于ＶｉｔＥ，最大脂质过氧化抑制率（４．０Ｇｙ）分别为５５．１％和５３．６％，两者的最佳用量分别为１０ｍｇ／ｇ体重和０．２５ｍｇ／ｇ体重，联合用药的作用效果（最大脂质过氧化抑制率为６０．１％）大于单独使用时的效果。     

一种新的产生和检测过氧亚硝基的化学发光体系

研究产生和消除过氧亚硝基（Peroxynitrite anion,ONOO^-）是自由基生物学和医学的一项紧迫任务。为此,建立了一种新的产生和检测ONOO^-的化学发光体系,并评估了检测的最佳条件。该方法为：10mmol／L羟胺与0．5mol,LNaOH、1mmol／L、乙二胺四乙酸二钠（Disodium ethylenediamine tetraacetate,EDTA）反应产生ONOO^-,随后用MnO2粉末过滤反应液以除去H2O2,然后在测量管内加入100μL抗氧化剂和860μL0．Imol／L的碳酸盐缓冲液（pH10）,再加入40μL过滤后的ONOO^-反应液、混匀、延迟10s,测10s化学发光强度。以抗氧化剂茶多酚、抗坏血酸、芦丁和黄芩苷作清除ONOO^-的实验。结果表明,本体系是一种灵敏价廉、可靠易行的筛选ONOO^-清除剂的新方法。     

大剂量X射线照射对雄性大鼠某些组织LPO水平及CuZn－SOD和Se－GSH－Px活性的影响

本研究观察大剂量Ｘ射线照射雄性大鼠７２ｈ后免疫和内分泌等组织脂质过氧化物（ＬＰＯ）水平及超氧化物歧化酶（ＣｕＺｎ－ＳＯＤ）和谷胱甘肽过氧化物酶（Ｓｅ－ＧＳＨ－Ｐｘ）活性的变化。结果发现，胸腺、脾脏、肾上腺和肝脏ＬＰＯ水平随照射剂量的增加而增高；脾脏和肝脏ＣｕＺｎ－ＳＯＤ活性在４Ｇｙ以上剂量照射后即升高，但在１０Ｇｙ照后增高明显；胸腺和脾脏Ｓｅ－ＧＳＨ－Ｐｘ活性在４Ｇｙ以上剂量照射后即明显高于对照组，睾丸Ｓｅ－ＧＳＨ－Ｐｘ活性也有增高趋势，其中１０Ｇｙ组增高明显；但是，４Ｇｙ以上剂量照射后胸腺ＣｕＺｎ－ＳＯＤ和肾上腺Ｓｅ－ＧＳＨ－Ｐｘ活性降低     

蜂花粉对受照大鼠抗辐射效应的研究

研究了口服蜂花粉对受照大鼠外周血白细胞（ＰＷＢＣ）数，血清超氧化物歧化酶总活力（Ｔ－ＳＯＤ），血清过氧化脂质（ＬＰＯ）终产物丙二醛（ＭＤＡ）和过氧化值（ＰＯＶ）的影响。结果表明“蜂花粉具有良好的抗辐射损伤的功能，即服食花粉组的ＰＷＢＣ数和Ｔ－ＳＯＤ明显高于对照的正常组和单放组。花粉线的ＭＤＡ和ＰＯＶ显著低于对照的正常组和单放组。提示蜂花粉的抗放射要理可能是由于蜂花粉能提高机体的造血重建力，提高体内     

富勒醇对贻贝棘尾虫的辐射防护机制

为进一步了解富勒醇对贻贝棘尾虫γ辐射防护的机制,在先前工作基础上测定了0．10mg mL^-1的富勒醇存在下,剂量为100-2000 Gy范围内贻贝棘尾虫辐照后第5d的存活率,并用光学和透射电子显微镜观察了辐照后贻贝棘尾虫形态和超微结构的变化,测定了与自由基相关的酶的活性（超氧化物歧化酶Superoxide dismutase,SOD和过氧化氢酶Catalase,CAT）和脂质过氧化产物（丙二醛Malondialdehyde,MDA和脂褐素Lipotusion,LIP）。结果表明,当剂量为100-1500 Gy时,富勒醇能明显提高贻贝棘尾虫γ辐照后的存活率,当剂量达到2000 Gy时,富勒醇对存活率无明显影响,表明富勒醇对贻贝棘尾虫γ辐射防护作用不仅和它浓度有关,而且与γ辐射剂量相关。显微镜观察结果在细胞和亚细胞层次揭示了贻贝棘尾虫辐射损伤的结构特征,并给出了富勒醇防护作用的附加证据。未加富勒醇辐照组中SOD和CAT的活性低于对照组（P〈0．01）,加富勒醇辐照组中SOD和CAT的活性明显高于未加富勒醇辐照组和对照组（P〈0．01,P〈0．01）,而加富勒醇辐照组中MDA和LIP的含量却显著低于对照组（P〈0．01,P〈0．05）和辐照组（P〈0．01）,由此推断富勒醇主要通过清除自由基,刺激SOD和CAT的活性,同时减少细胞膜上的脂质过氧化反应,达到对贻贝棘尾虫的辐射防护作用。     

前列腺抗原酶促化学发光免疫分析方法学的建立

应用鲁米诺-过氧化氢发光体系建立定量测定血清前列腺特异性抗原含量的酶促化学发光免疫分析方法。该方法测量范围为1.5～80μg/L,灵敏度为0.12μg/L,批内变异＜5%,批间变异＜15%。回收率为83.8%～118.7%,稀释实验测定值与稀释度呈线性相关,相关系数为0.999。本方法与免疫放射分析方法的相关方程y=1.07x+0.68,相关系数r=0.97。     

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。     

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.     

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.     

有效探测面积大于1000 cm2的正比计数器测量系统性能测试

为对自制的活性面积高达1 000 cm²的大面积源进行表面发射率定值,同时作为现有2πα、2πβ表面发射率标准装置能力的扩充,研制了一套内置式大面积2π多丝正比计数器测量系统,并利用活性区直径为8 mm的²⁴¹Am点源及活性区面积为10 cm×15 cm的大面积²⁴¹Am和⁹⁰Sr-⁹⁰Y源对其进行计量学性能测试。结果表明：计数器内计数响应均匀性优于±0.4%,有效探测面积达1 400 cm²;所得²⁴¹Am源高压坪曲线的坪长为1 400 V,坪斜为0.27%/100 V,坪区内计数变化为0.87%;⁹⁰Sr-⁹⁰Y源高压坪曲线的坪长为300 V,坪斜为0.75%/100 V,坪区内计数变化为0.80%;10次测量重复性好于0.4%,8 h内短期稳定性好于0.3%,1 a内长期稳定性好于0.8%。     

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.     

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.     

The role of AGFA high-energy CR in the calibration and quality control of multileaf collimators （MLC）

Linear accelerators equipped with multileaf collimators （MLC） are becoming more common and are widely used in the intensity-modulated radiotherapy （IMRT）. There is an imperative need to ensure the commissioning specification of the linear accelerators for the sake of quality assurance （QA） and quality control （QC）. This paper is aimed to investigate the role of AGFA high-energy CR （Computed Radiography） in calibrating dynamic multileaf collimators and evaluating the accuracy of the leaf position. The result shows that AGFA high-energy CR can easily and conveniently be used to calibrate MLC and verify its position. Hence, the application of AGFA high-energy CR is proved to be an accurate and time-saving method for routine MLC QC, especially when MLC calibration adjustments are required.