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1.
建立一种反向高效液相色谱法定量检测蛹虫草培养基中活性成分腺苷含量和虫草素含量的方法.色谱柱为Eclipse XDB-C18柱(4.6 mm×150 mm,5μm);流动相:0.02 mol/L KH2PO4∶甲醇(体积比85∶15)溶液;流速:1.0 mL/min;检测波长:260 nm.腺苷的线性测量范围为0.5~100μg/mL(R=0.999 9),平均回收率为105.3%,标准品RSD=0.76%(n=5),样品RSD=1.87%(n=5);虫草素的线性测量范围为0.5~100μg/mL(R=0.999 9),平均回收率为104.0%,标准品RSD=0.95%,样品RSD=1.23%.本测定方法线性范围宽、分离度好、具有良好精密度,可定量、准确分析不同蛹虫草培养基中活性成分腺苷和虫草素含量.  相似文献   

2.
采用香豆素类物质BDMC为衍生剂进行柱前衍生,以C8反相柱(4.6mm×150mm)为固定相,乙腈-甲醇-水(35∶10∶55)为流动相,流速为1.5mL/min,柱温为22℃,检测波长为Ex/Em=354nm/440nm,建立定量检测体外培养巨噬细胞液中PGF2α的HPLC方法.PGF2α峰呈尖峰,分离度良好;在25~500μg/L范围内成线性(R2=0.995 0);其精密度RSD为4.34%(n=5);重复性RSD为7.88%(n=6),稳定性RSD为4.43%(n=5);平均加样回收率为87.20%±7.63%(n=3).结论:该方法稳定、可靠、重复性好,可用于体外培养巨噬细胞液中PGF2α的定量检测.  相似文献   

3.
采用反相高效液相色谱法检测人体血浆中替勃龙的含量.以5倍样品体积的乙腈萃取2次,经氮气吹干,甲醇溶解后,上机分析.采用Promosil-C18色谱柱(4.6mm×250mm,5μm),流动相:甲醇-乙腈-水,流速:1.0mL/min,进样量:10μL,检测波长:204nm,柱温:25℃.在优化的色谱条件下,替勃龙在0.5~250.0μg/mL内线性关系良好(r=0.999 9),最低检测限为0.05μg/mL,平均回收率(n=3)为92.7%,RSDs小于1.6%.本方法简单,灵敏,准确,适合于体内替勃龙含量的检测与分析.  相似文献   

4.
火焰原子吸收光谱法测定雷公藤中的铅和镉   总被引:1,自引:0,他引:1  
用火焰原子吸收光谱法对雷公藤中的Pb和Cd进行了分析测定.结果显示,用HNO3和H2O2(5:2)混合作消解液处理样品,精密度与回收率较好.检出限分别为0.25μg·mL-1和0.036μg.mL-1,RSD为2.5%和3.7%(n=5),回收率为97%和101%对Pb和Cd.  相似文献   

5.
建立了高效液相色谱法检测鸡蛋中三聚氰胺的方法。样品用1%三氯乙酸和2.2%乙酸铅超声提取。色谱柱为HypersilODS100×4.6mm,5μm;流动相为乙腈:辛烷磺酸钠离子对试剂(pH=3)=15:85(V/V);流速为1mL/min;检测波长为210nm;柱温为40℃。三聚氰胺在0.2μg/mL~10μg/mL范围内,有良好的线性关系。在空白样品中添加0.2μg/mL、0.4μg/mL、1.0μg/mL三个质量浓度的标准工作液,回收率在82.0%~104.0%,相对标准偏差为6.81%(n=9)。  相似文献   

6.
雷公藤甲素与雷公藤红素是雷公藤的主要生物活性成分,具有多种潜在的药理作用与毒性。神经炎症是各种神经退行性疾病的共同特征,小胶质细胞的激活是中枢神经系统神经炎症的主要组成部分。本文用雷公藤甲素与雷公藤红素处理小胶质细胞(HMO6),探究其对小胶质细胞增殖、细胞膜完整性的影响,以及雷公藤甲素对小胶质细胞M1、M2极化的影响。结果表明:与对照组相比,雷公藤红素(10-4 mol/L)处理HMO6后,细胞增殖抑制率可高达(71.91±16.28)%(P<0.01,n=3),当浓度为10-5 mol/L时,乳酸脱氢酶(LDH)释放量明显增加(8.58±1.56)%(P<0.01,n=4);与对照组相比,雷公藤甲素处理HMO6后,对细胞膜完整性无显著影响,但当浓度为10-5 mol/L时,细胞增殖抑制率可高达(94.31±0.62)%(P<0.01,n=5),与脂多糖(LPS)组相比,雷公藤甲素浓度为10-7 mol/L时人肿瘤坏死因子-α(TNF-α)释放量显著减少至(264.83±64.25)pg/mL(P<0.01,n=3),人白细胞介素-10(IL-10)释放量减少至(63.48±16.79)pg/mL(P<0.05,n=3)。  相似文献   

7.
采用高效液相色谱法,测定人参叶中的主要黄酮类成分人参黄酮苷[山柰酚-3-O-β-D-半乳糖(2→1)-β-D-葡萄糖苷]的质量分数.色谱条件:Zorbax Extend C18柱(250mm×4.6mm,5μm),流动相为V(甲醇):V(乙腈):V(体积分数为0.1%的醋酸水溶液)=25:5:70,流速为1.2mL/min,检测波长268nm,色谱柱温度为25℃.结果表明:在进样量0.5~20.0μg范围内线性关系良好,相关系数r=0.9999(n=6);人参黄酮苷的平均回收率为98.5%;RSD=0.64%(n=6)。  相似文献   

8.
建立一种简单的反相离子对HPLC方法测定盐酸二甲双胍中的双氰胺和三聚氰胺的含量.使用Hypersil ODS C18反相色谱柱(5μm;250×4.6 mm),乙腈-离子对试剂水溶液(10 mmol/L戊烷磺酸钠+10 mmol/L柠檬酸,pH为3.0,体积比10∶90)为流动相,流速1.0 mL/min,检测波长217 nm,柱温25℃.结果表明:双氰胺在0.0220μg/mL浓度范围内线性关系良好,相关系数R=0.999 9,平均回收率为97.6%,RSD=0.29%;三聚氰胺在0.0220μg/mL浓度范围内线性关系良好,相关系数R=0.999 9,平均回收率为97.6%,RSD=0.29%;三聚氰胺在0.0250μg/mL浓度范围内线性关系良好,相关系数R=0.999 9,平均回收率96.5%,RSD=0.32%.双氰胺和三聚氰胺的检出限分别为4.0 ng/mL和6.0 ng/mL.该方法简单、快速、准确、灵敏,适于同时测定盐酸二甲双胍制剂中的双氰胺和三聚氰胺的含量.  相似文献   

9.
运用高效液相色谱法测定连钱草中迷迭香酸含量. 方法:运用Hypersil ODS(4.6×250mm, 5μm) Agilent分析柱进行测定,流动相:甲醇- 0.1%磷酸(40:60);流速:1mL/min;检测波长 :330nm;柱温为25℃. 结果:迷迭香酸与其它组分的分离效果好,且在0.15~3.06μg内呈良好的线性关系(r=0.99998),平均回收率为99.3%(RSD=1.1%,n=6).结论:该测定方法能有效地消除连钱草中其它成分的干扰,简便易行,重现性好,可作为连钱草质量控制的定量依据和含迷迭香酸植物资源调查的分析依据.  相似文献   

10.
反相高效液相色谱法测定太太美容口服液中阿魏酸的含量   总被引:4,自引:0,他引:4  
建立了太太美容口服液中阿魏酸含量的HPLC测定方法.色谱柱为Shim-PackVP-ODS柱(150mm×4·6mm,5μm);流动相为甲醇水冰醋酸(32∶66∶2);流速1mL/min;323nm处进行检测.阿魏酸的线性范围为0·252~5·04μg/mL,r=0·9993,平均回收率为99·9%(n=5),相对标准偏差为1·2%.实验证明该方法简便、快速、准确,适合于太太美容口服液中阿魏酸含量的测定.  相似文献   

11.
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.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
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   

14.
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。  相似文献   

15.
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.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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-  相似文献   

20.
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-  相似文献   

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