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1.
鱿鱼鱼精蛋白抗菌活性的研究   总被引:1,自引:0,他引:1  
测定了鱿鱼鱼精蛋白对食品污染菌的抑制效果和最低抑菌浓度(MIC),并通过试验证明了鱿鱼鱼精蛋白通过与甘氨酸、醋酸钠的复配,对革兰氏阴性菌的抗菌活性有所提高。  相似文献   

2.
 功能化铁氧磁性纳米粒在生物医学中应用广泛,可用于肿瘤磁感应热疗、磁共振成像(Magnetic Resonance Imaging,MRI)、药物输送及磁转染等方面。为了探讨鱼精蛋白功能化修饰的铁氧磁性纳米粒的制备及其作为基因载体在体外磁转染中的可行性,采用共沉淀法制备Fe3O4磁性纳米粒,经表面氨基化修饰后在其表面偶联鱼精蛋白。利用透射电镜、傅里叶红外光谱仪、zeta电位与粒度分析仪等,对磁性纳米粒进行形态、粒径及zeta电位分析等表征检测。共聚焦显微镜观察磁转染方法转染报告基因绿色荧光蛋白质粒pEGFP-N1进入HepG2细胞的表达,以真核转染试剂vigofect为对照。结果显示,实验中制备的磁性纳米粒粒径10nm左右,在交变磁场下具有良好的升温性能。鱼精蛋白功能化修饰磁性纳米粒后,其zeta电位进一步增大,更利于与DNA有效结合,在HepG2细胞系,其转染pEGFP-N1质粒的效率高于vigofect。研究表明,鱼精蛋白功能化修饰的铁氧磁性纳米粒可作为磁转染的有效载体,由于其同时具备在交变磁场下升温的性能,在基因治疗联合热疗的研究领域具有一定的应用价值。  相似文献   

3.
为避免鱿鱼腐败变质,延长其货架期,以鱿鱼腐败菌为指示菌,测定花椒、大料、胡椒、壳聚糖以及鱼精蛋白的抑菌性能,选取抑菌性较好的保鲜剂进行响应面优化,筛选鱿鱼复合生物保鲜剂最佳配方,并进行平板验证.结果表明大料、壳聚糖和鱼精蛋白对鱿鱼腐败菌具有较好的抑菌效果,花椒和胡椒对鱿鱼腐败菌基本无抑制作用.壳聚糖和鱼精蛋白对鱿鱼腐败菌的最小抑菌浓度(MIC)分别为4.8 mg/mL和2.4 mg/mL.3种抑菌性能较好的保鲜剂对鱿鱼腐败菌抑制效果影响的主次顺序为鱼精蛋白壳聚糖大料,鱼精蛋白和壳聚糖添加量对复合保鲜剂的抑菌性能有极显著影响(P0.01),大料添加量对复合保鲜剂的抑菌性能影响不显著(P0.05).复合保鲜剂最佳配方为:鱼精蛋白2.39 mg/mL,壳聚糖4.8 mg/mL,大料100 mg/mL.平板验证结果显示,等量复合保鲜剂抑菌圈直径达到模型预测值的96.75%,说明获得的模型能够很好的预测复合生物保鲜剂对鱿鱼腐败菌的抑制作用.  相似文献   

4.
不同剂量鱼精蛋白对肝移植新肝期凝血功能的影响   总被引:1,自引:0,他引:1  
目的探讨不同剂量鱼精蛋白对肝移植术患者新肝期凝血功能的影响.方法拟行原位肝移植术的肝病患者30例,随机分为4组,在新肝期下腔静脉开放后分别不用鱼精蛋白(Ⅰ组,n=7)或应用鱼精蛋白0.4 mg/kg(Ⅱ组,n=8)、0.6 mg/kg(Ⅲ组,n=7)、0.8 mg/kg(Ⅳ组,n=8).于入室后、下腔静脉开放后、新肝期应用鱼精蛋白后10 min,1,2,3 h,分别抽取中心静脉血,测定全血激活凝血时间(ACT)和肝素活性;记录围术期失血量、液体出入量、促凝血物质的用量和输血量.结果在肝移植期间4组患者的ACT和血浆肝素活性之间有统计学意义(P<0.05),其中Ⅰ组和Ⅱ组之间无统计学意义(P>0.05),Ⅲ组和Ⅳ组之间无统计学意义(P>0.05),而Ⅱ组与Ⅲ组之间有统计学意义(P<0.05).4组患者在肝移植期间的出血量无统计学意义(P>0.05),胶体液、晶体液、血小板、白蛋白、凝血酶原复合物和纤维蛋白原用量以及输血量无统计学意义(P>0.05),液体总入量无统计学意义(P>0.05).结论在新肝期下腔静脉开放后给成人患者应用0.6 mg/kg的鱼精蛋白即可消除新肝期肝素对凝血功能的影响,但对总出血量、总输血量和促凝血物质无明显影响,应用鱼精蛋白只能改善凝血功能.  相似文献   

5.
鱼精蛋白的研究与开发   总被引:3,自引:0,他引:3  
鱼精蛋白是一种重要的天然食品防腐剂.本文对它的基本特性、制备、抗菌性以及应用进行了综述.  相似文献   

6.
利用阳离子脂质体作为载体,用其搭载鱼精蛋白与STAT3 siRNA复合物,通过一系列实验证实该复合体系可显著抑制STAT3基因在黑色素瘤细胞B16中的表达,促进肿瘤细胞的凋亡。首先对载体材料进行了一系列表征测定,检测了不同复合比例下载体和siRNA复合物的粒径和电位。利用载体和siRNA的复合物对B16细胞进行转染并测定转染效率,随后对复合材料的毒性进行了检测。此外还进行了细胞凋亡、平板克隆、荧光定量PCR以及Western Blot等一系列实验来进一步确定载体复合物的有效性。实验结果表明,阳离子脂质体搭载复合了鱼精蛋白的STAT3siRNA表现出了良好的靶向治疗性及优秀的递送效率,且复合体系稳定性良好,毒性低。  相似文献   

7.
棕色固氮菌无细胞提取液,用热处理和鱼精蛋白分级沉淀法除去杂蛋白及核酸。随后,在DEAE——纤维素柱上用MgCl_2梯度洗脱,获得了分离较好的钼铁蛋白和铁蛋白两个组分,它们单独没有活力,合起来具有较高的活力。并对两个蛋白的配比、吸收光谱等做了初步的研究和探讨。  相似文献   

8.
鲢鱼(Aristichthys nobilis)鱼精蛋白的纯化和鉴定   总被引:5,自引:0,他引:5  
采用Sephadex G-50凝胶层析、GM-Sepharose CL 6B离子交换层析及反相高压液相色谱等步骤从鲢鱼鱼精蛋白的粗品中分离得到一种具有抗菌活性的蛋白质。经SDS-PAGE及生物质谱鉴定,该蛋白质为单一组份,分子量为13331.9.Da。该蛋白分子中碱性氨基酸总量为33.4%,N-末端序列为NH2-Pro-Gln-Arg-His-Lys。  相似文献   

9.
尿激酶能激活纤维蛋白溶酶原,成纤维蛋白溶酶,后者能使含有大量精氨酸的鱼精蛋白充分水解,水解产物和2、4、6——三硝基苯磺酸反应生成在420nm 具光吸收的中间物。当尿激酶浓度低于每毫升40国际单位时,光吸收和尿激酶浓度成直线关系。本方法在灵敏度和重复性上都比较满意,也可用于纤维蛋白溶酶原的定量测定。  相似文献   

10.
研究了影响蛋白和SDS结合比例的各种因素.该比例与离子强度无关,但与巯基乙醇和SDS的质量分数相关.建立了测定蛋白-SDS胶束中蛋白与SDS结合比率的方法.当总SDS质量分数为蛋白质量分数的3倍左右,离子强度小于0.2,测出牛血清白蛋白、鱼精蛋白、溶菌酶、胰蛋白酶和胃蛋白酶的蛋白/SDS比例分别为1∶1.42、1∶1.62、1∶1.36、1∶1.53和1∶1.41.而乙醇酸氧化酶的蛋白/SDS比例则仅为1∶0.23.  相似文献   

11.
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   

12.
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   

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

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
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   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
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   

20.
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   

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