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1.
采用噬菌体表面展示十二肽库对心肌型脂肪酸结合蛋白(H FABP)特异性亲和配体进行筛选, 经3轮筛选及序列比对后得到一个酶联免疫测定分析 (ELISA)检测阳性特征序列: W P N H H M L H K R W P. 对此序列进行肽合成, 并标记上荧光标记物芘, 经高效液相纯化、 冻干及质谱确定其分子量后制成荧光肽探针检测急性心肌梗塞病人血样, 结果均呈阳性. 结果表明, 所获得的肽探针具有较好的临床应用效果.心肌型脂肪酸结合蛋白; 噬菌体表面展示十二肽库; 亲和配体; 酶联免疫测定分析  相似文献   

2.
环境可降解地膜降解后形成大量低相对分子质量残体,这些低相对分子质量残留物累积在土壤耕作层,对土壤微环境及作物生长发育构成潜在危害.这些残留物可在土壤中进一步降解,但其降解进程尚不清楚.研究这类低相对分子质量残留物碎化降解和无机矿化进程,对进一步优化可降解地膜配方、生产工艺及提高可降解地膜的环境安全性具有重要的实践意义.选用相对分子质量分别为2 000(M1)、5 000(M2)和100 000以上(M3)的聚乙烯(L-PE),以不同累积量(1、10、50和100 a量)添加到不同质地(壤土、砂土、黏土)的土壤中,经盆栽种植一季小麦后,采用十氢萘高温融化法从土壤中提取L-PE,用凝胶渗透色谱法(GPC)检测L-PE相对分子质量及其分布的变化.结果显示,十氢萘高温融化法未改变L-PE的结构特征;L-PE相对分子质量大于5 000时,其提取率达74.47%~97.48%,提取率随相对分子质量增加而提高;经盆栽种植一季小麦后,添加到土壤中的3种相对分子质量的L-PE(M1、M2、M3)均发生了不同程度的降解,降解效果为M3M1M2.  相似文献   

3.
目的:研究急性心肌梗死(AMI)患者血清心型脂肪酸结合蛋白(H-FABP)与早期心功能的相关性.方法:收集AMI患者209例及对照组98例;入院后6h内测定血清H-FABP,按照心功能Killip(Ⅰ-Ⅳ)分级、左室射血分数(LVEF)、左室舒张末期内径(LVEDd)及E/A比值进行分组,对比各组间血清H-FABP的差异;分析血清H-FABP与心功能参数的相关性.结果:AMI患者血清H-FABP随心功能Killip分级增加而显著升高(P0.05);随LVEF水平降低,血清H-FABP水平均逐渐升高(P0.05);随着LVEDd的增加,血清H-FABP逐渐升高(P0.05);E/A比值≤1组血清H-FABP水平高于E/A比值1组(P0.05);血清H-FABP水平与LVEF、E/A比值呈负相关(r分别为-0.563,-0.497,P0.05);与LVEDd呈正相关(r=0.519,P0.05).结论:AMI患者血清H-FABP水平随Killip(Ⅰ-Ⅳ)分级增加逐渐升高;血清H-FABP与AMI早期LVEDd呈正相关,与LVEF、E/A比值呈负相关,血清H-FABP水平与AMI早期心功能参数具有相关性,对于AMI早期心功能评估具有重要价值.  相似文献   

4.
Δ~(12)-脂肪酸脱氢酶是多不饱和脂肪酸合成的关键酶.参考已知的Δ~(12)-脂肪酸脱氢酶基因序列设计特异性引物,通过PCR扩增从红冬孢酵母YM25235中获得了全长为1 341 bp的一个cDNA序列.序列分析表明,该序列具有一个编码446个氨基酸、相对分子质量为50.6 ku的完整开放阅读框,所编码的氨基酸序列与Δ~(12)-脂肪酸脱氢酶相似性最高但并不相同,而且也具有Δ~(12)-脂肪酸脱氢酶特异性的3个组氨酸保守区,表明该序列为一个新的编码Δ~(12)-脂肪酸脱氢酶的基因.为了验证功能,将该基因序列克隆到表达载体pYES3/CT中,构建重组质粒pY3RKD12,并转化到酿酒酵母的缺陷型菌株INVSCI中进行异源表达.通过脂肪酸气相色谱(GC)分析表明,在pY3RKD12转化的酵母细胞总脂肪酸中出现一个保留时间和亚油酸甲酯标准品相同的新峰,其含量占酵母总脂肪酸的3.76%,但在pYES3/CT转化的酵母细胞总脂肪酸中没有检测到.这些结果证明所克隆的序列是一个新的Δ~(12)-脂肪酸脱氢酶基因,其表达的蛋白质可催化油酸合成亚油酸.  相似文献   

5.
IPDI为硬段,PEG、PPG为软段,DMPA、DEG为扩链剂,TEA为中和剂合成了聚氨酯预聚体.以PEG的相对分子质量、-NCO/-OH(n/n)、PEG/(PEG+PPG)(n/n)和SF/(SF+PU)(m/m)为4个影响因素设计了四因素四水平正交实验并制备了一系列丝素蛋白/聚氨酯复合水凝胶.采用非限制性压缩试验对水凝胶进行抗压缩性能测试,并通过方差分析法对实验结果进行分析.结果表明PEG的相对分子质量对水凝胶的抗压性能影响最明显.PEG的相对分子质量为600、1 000、2 000、4 000时所制备的丝素蛋白/聚氨酯复合水凝胶的抗压模量均在0.35~1.20 MPa之间.  相似文献   

6.
人心肌肌钙蛋白Ⅰ(hcTnI)是临床检测心肌损伤及预后提供诊断的生物学指标,由于来源有限,采用基因重组技术,以期获得高表达量的人心肌肌钙蛋白Ⅰ.人工合成hcTnI基因,将其插入pET-11a载体中,通过酶切鉴定正确后转入表达宿主菌BL21(DE3)中,诱导表达目的蛋白.采用蛋白免疫印迹反应(Western Blot,WB)鉴定表达目的蛋白的免疫特异性.经SDS-PAGE证实重组蛋白的相对分子质量约为2.6×104,凝胶密度扫描软件检测到目的蛋白占总蛋白比例为30.1%,WB实验验证诱导后目的蛋白特异性良好.成功构建了重组hcTnI基因在大肠杆菌表达的工程菌株,并获得表达,为制备高特异性的抗体及临床检测应用和测定标准化奠定了基础.  相似文献   

7.
以聚酯二元醇、甲苯二异氰酸酯(TDI)、二羟甲基丙酸(DMPA)、1,4-丁二醇(BDO)和三羟甲基丙烷(TMP)等为原料合成了双组分水性聚氨酯(WPU)的多元醇组分.考虑到溶解性、反应活性、工业成本等因素,本研究从小分子二元醇(如乙二醇、丙二醇、丁二醇、一缩乙二醇等),小分子三元醇(甘油),小分子四元醇(季戊四醇),聚乙二醇(相对分子质量200~2 000),聚丙二醇(相对分子质量300~2 000)等数十种醇类化合物中,反复试验,再三筛选,最后确定以聚乙二醇-800和六亚甲基二异氰酸酯(HDI)三聚体为原料合成了亲水性多异氰酸酯固化剂组分.将多元醇组分和固化剂组分混合配制,得到了双组分WPU胶黏剂.通过红外光谱(FT-IR)、核磁共振(NMR)、黏度、吸水率、黏接强度、离心稳定性等性能测试,分别对多元醇组分和固化剂组分合成的关键步骤及影响产物性能的各种因素进行了探讨.结果表明,当DMPA、BDO、TMP的质量分数分别为6%、4%、3%时,多元醇组分的外观、稳定性、黏接强度等性能较好;选择聚乙二醇作为亲水组分对HDI三聚体进行改性,且当其添加的质量分数为11%及以上时,制备出的多异氰酸酯固化剂组分具有较好的水分散性.  相似文献   

8.
上世纪80年代,免疫组织化学(Immunohistochemistry,IHC)技术得到发展,法医病理学家开始将这一技术应用于法医学领域,主要用于寻找心脏性猝死早期心肌缺血的病理形态学依据、青壮年猝死综合症的发病机理的研究、不典型心肌炎的死因诊断等。近年来应用于法医病理学研究的诊断标志物主要有心肌肌动蛋白(Actin)、肌钙蛋白Ⅰ(cTnⅠ)、纤维连接蛋白(Fn)、纤维蛋白原(Fg)、碱性成纤维细胞生长因子(bFGF)、早期生长反应因子(Zif/268)、血管内皮生长因子(VEGF)、心脏脂肪酸结合蛋白(H-FABP)、CD68、肌红蛋白(Mb)、Cx43、内皮素(Endothelin,ET)、补体C5、细胞调亡相关蛋白Bcl-2和Bax等。  相似文献   

9.
嗜热厌氧乙醇菌JW200中乙醛脱氢酶的纯化   总被引:3,自引:0,他引:3  
研究了嗜热厌氧乙醇菌(Thermoanaerobacter ethanolicus)JW200中乙醇代谢途径的关键酶之一乙酰CoA依赖型的乙醛脱氢酶(acetaldehyde dehydrogenase, ALDH, EC 1.2.1.10)的纯化.结果表明,经DEAE Sepharose Fast Flow阴离子交换层析、两次为30%与80%硫酸铵盐析和相应盐浓度的Butyl-HIC疏水层析、TOYOPEARL HW-55F分子筛层析等提纯步骤,可得到电泳纯的ALDH,其提纯倍数为910倍,得率为7%.由SDS-PAGE和梯度PAGE测得全酶由4个亚基组成,全酶相对分子质量为360 000,亚基相对分子质量为100 000.  相似文献   

10.
以蛋白水解度和酶解液中海参肽相对分子质量的分布作为指标,考察不同蛋白酶的酶解效果,筛选水解海参内脏的最适合蛋白酶,并通过单因素实验和正交实验优化酶解工艺.实验结果表明:胰蛋白酶的水解效果最佳,可用于水解海参内脏制备海参肽;在底物质量分数为1.0%,加酶量为0.375 1mkat·g~(-1),pH值为8.0,酶解温度为37℃,水解时间为5h的最优酶解条件下,海参内脏的水解度可达到48.90%,酶解液中的多肽(2 000~5 000u)质量分数为52.68%,寡肽(含氨基酸)(≤2 000u)质量分数为47.25%.  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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