胶体金免疫试纸法快速测定雌三醇

雌三醇(E3)在临床诊断、日用化工和畜牧业等领域具有广泛应用,同时它也是一种环境污染物,对E3的检测具有科学和应用意义.本研究采用竞争性免疫层析技术,以E3单克隆抗体-纳米胶体金复合物作为金标抗体,以E3偶联抗原为检测线(T线)、以羊抗鼠抗抗体为控制线(C线),通过条件的优化,制备出检测E3的胶体金试纸条.当试纸条C线和T线同时显色时,结果为阴性;当试纸条仅C线显色时,结果为阳性.所得检测试纸条测加标水样的最低检测限为100μg/L,测加标奶样的最低检测限为100μg/L,反应时间为10min,与雌酮、雌二醇、己烷雌酚等环境雌激素无交叉反应,具有良好的选择性.     

基于适配体的胶体金色谱层析试纸条快速检测肌酸激酶同工酶

研究基于适配体的胶体金色谱层析试纸条快速检测肌酸激酶同工酶,用于揭示长期飞行下航天员潜在的心肌和肌肉损伤.利用SELEX方法筛选得到的肌酸激酶同工酶适配体,并优选出与肌酸激酶同工酶有较强亲和能力的核酸适配体应用于胶体金免疫层析试纸条,通过优化胶体金颗粒大小、缓冲液浓度等条件,成功建立了一种基于适配体的胶体金试纸法用于CK-MB的快速检测.实验结果表明,通过基于磁珠的核酸适配体筛选方法筛选出的与肌酸激酶同工酶有亲和力的核酸适配体,能够用于构建适配体-适配体夹心胶体金免疫层析试纸条并成功应用于82 nM以上的肌酸激酶同工酶的快速、可视化检测,同时,该免疫层析试纸条具有良好的特异性和稳定性,可用于未来空间医学即时检测.     

适配体-纳米金比色传感法检测磺胺二甲氧嘧啶

以未修饰的纳米金(AuNPs)作为比色指示剂,具有特异性识别功能的适配体为传感探针,NaCl溶液作为聚集诱导剂,通过改变AuNPs聚集程度,建立了一种快速检测磺胺二甲氧嘧啶(SDM)的可视化比色传感方法.采用紫外可见分光光度计、透射电子显微镜和电位分析仪对AuNPs形貌及聚集程度进行了表征;考察了NaCl浓度、适配体浓度、适配体和AuNPs反应时间对AuNPs聚集程度的影响.结果表明:适配体-纳米金比色传感法检测SDM的最优反应条件为66.7 mmol/L NaCl,20.0 nmol/L适配体,反应时间5 min;AuNPs溶液在670 nm和520 nm处的吸光度比值(A_(670)/A_(520))与SDM在0.033～3.333μmol/L内呈良好的线性关系,相关系数为0.994 3;利用该比色传感法成功检测了尿样中的SDM,回收率为99.3%～105.1%时.因此,该适配体-纳米金比色传感法具有操作简单、耗时短、裸眼可视等优点,在SDM的现场快速分析检测中具有重要意义.     

牛奶中三聚氰胺残留胶体金免疫层析快速检测方法研究

为建立牛奶中三聚氰胺免疫层析快速检测方法,采用胶体金偶联特异性三聚氰胺抗体,优化试纸条T线抗原包被量、金标抗体用量、二抗稀释倍数等条件,构建三聚氰胺免疫层析试纸条.结果表明,T线抗原包被量为0. 25μg/mL,金标抗体用量为9. 0μL/条,二抗稀释倍数为1:100时效果最佳;最优条件下该试纸条的最低检出限为0. 25μg/mL,结果可在5 min内进行判读,且牛奶样品不需任何处理可直接进行测定.本研究建立的免疫检测方法适用于牛奶中三聚氰胺的检测.     

甘草酸18位差向异构体不同配比和浓度对Caco-2细胞P-gp功能的影响

研究甘草酸18位差向异构体18α-甘草酸(18α-Gly)与18β-甘草酸(18β-Gly)不同配比和浓度对结肠癌(Caco-2)细胞P-糖蛋白(P-gp)功能的影响,选择最佳浓度比例.建立细胞模型,选择甘草酸总浓度为1∶10∶30∶60∶120∶240 μmol/L,18α-Gly与18β-Gly物质的量比分别为10∶0、8∶2、6∶4、5∶5、4∶6、2∶8、0∶10,根据细胞存活率,选择合适浓度比例,利用流式细胞仪测定细胞内荧光强度,寻找荧光强度最大的浓度比,即对P-gp抑制作用最强,P-gp功能最弱.研究结果表明甘草酸总浓度为1 μmol/L时,随着18α-Gly比例的减少,荧光强度逐渐减弱,P-gp诱导作用逐渐增加.甘草酸总浓度为10 μmol/L和60 μmol/L时,随着两者物质的量比的变化,荧光强度变化明显;当总浓度为10 μmol/L,n(18α-Gly)∶n(18β-Gly)=4∶6时,荧光强度较强,抑制作用明显;当总浓度为60 μmol/L,两者物质的量比为5∶5时荧光强度最强,抑制作用最强.     

时间分辨荧光微球免疫层析法定量检测克伦特罗

建立了一种定量检测克伦特罗的时间分辨荧光微球免疫层析法。对抗体标记量、微孔中克伦特罗抗体-时间分辨荧光微球探针的体积以及检测线上抗原浓度进行了优化。通过时间分辨荧光微球试纸条检测仪读取试纸条上检测线和质控线的信号强度,以克伦特罗标准品的浓度为横坐标,以检测线和质控线信号强度的比值为纵坐标建立标准曲线。结果表明:该方法定量检测范围为0.01~0.81μg/L,检测限为0.004μg/L,半抑制率为0.06μg/L。本检测方法具有简便、灵敏度高、快速和可定量等特点,适合于大批量样品的现场筛查。     

双酚A电化学适配体传感器的研究

制备了一种检测双酚A的电化学适配体传感器。将末端带巯基的双酚A适配体DNA链通过自组装作用固定在金电极表面,以铁氰化钾-亚铁氰化钾平衡电对为电化学信号探针,利用循环伏安法、交流阻抗法和差分脉冲伏安法对适配体传感器进行表征和定量测定。结果表明,适配体传感器检测双酚A的线性范围为1.0×10~(-15)~1.0×10~(-12)mol/L,检出限为6×10~(-16)mol/L(S/N=3)。该传感器制作过程简单,灵敏度高,可用于自来水中双酚A的测定。     

脊髓灰质炎病毒Ⅰ型抗体胶体金检测试纸条的研制

目的:为研制快速检测脊髓灰质炎病毒Ⅰ型抗体的胶体金试纸条.方法:以辛酸-硫酸铵沉淀法纯化脊髓灰质炎病毒Ⅰ型单克隆抗体,用柠檬酸三钠还原法制备胶体金溶液,胶体金标记单抗,再结合脊灰病毒抗原形成复合物,固定于金标垫上,将鼠抗人IgG和羊抗鼠IgG分别包被于试纸条的T (检测线)处和C (质控线)处,应用该试纸条进行性能检测.结果:以已知的脊灰病毒Ⅰ型阳性血清作为检测样品,试纸条检测的灵敏度为1:80;特异性试验证明该试纸条与甲型肝炎病毒、乙型肝炎病毒、麻疹病毒抗体阳性血清没有交叉反应;检测结果与脊灰病毒Ⅰ型疫苗抗体检测试剂盒(ELISA)试验的符合率为86.7%.结论:该试纸条检测脊灰病毒Ⅰ型的抗体水平具有较好的特异性与灵敏性,适用于大规模临床血清抗体水平检测,具有良好的应用前景.     

双电位比率型量子点ECL适配体传感器的构建及其应用

比率型电致化学发光适配体传感器检测目标时可显示两种不同的ECL信号,以往对比率型ECL传感的研究大多基于鲁米诺-过氧化氢(Luminol-H_2O_2)体系。研究设计了一种基于硒化镉量子点(CdSe QDs)和钌联吡啶修饰的钌硅纳米粒子(RuSi@Ru(bpy)_3~(2+)NPs)的双电位比率型ECL适配体传感器,用于卡那霉素超灵敏高选择性检测。分别选取CdSe QDs和RuSi@Ru(bpy)_3~(2+)NPs作为阴极和阳极ECL发光体。通过卡那霉素两条互补的适配体链作为连接CdSe QDs与RuSi@Ru(bpy)_3~(2+)NPs的媒介,通过酰胺偶联反应在玻碳电极表面构建检测卡那霉素传感器。卡那霉素检测浓度范围为1.0 fmol/L～10 pmol/L。线性拟合方程为△I=0.132 lg c+2.133,相关系数为0.999 (c代表卡那霉素浓度,mol/L)。信噪比S/N=3时,检测限(LOD)为0.4 fmol/L。研究结果为两个ECL发光体构建比率型ECL传感器提供了新思路。     

辣椒、花椒中罗丹明B免疫层析分析

为建立以胶体金标记抗体为基础的罗丹明B(RB)快速检测技术,利用戊二醛法将RB的衍生物罗丹明123(R123)与牛血清白蛋白(BSA)、卵清白蛋白(OVA)分别合成完全抗原(R123-BSA)和包被抗原(R123-OVA),对雌性大耳白兔皮下注射R123-BSA获得多克隆抗体.胶体金作为示踪标记物标记到硝酸纤维素膜(NC膜)上,涂覆R123-OVA作为检测线,用羊抗兔IgG作为质控线,通过优化实验条件,开发了渗滤式胶体金免疫快速检测试纸条,研制出RB标准品浓度比色卡.以比色卡作为判定依据,以辣椒、花椒为研究对象,消除基质影响,进行试纸条检测.结果表明:RB线性为0.01~20 ng/mL,其最低检出限为0.5 ng/mL,试纸条显色结果明显.该试纸条实验成功,无需特殊设备即可实现现场快速检测,适用于快速定性检测香料中RB.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the