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131.
敬钊毒素-I(JZTX-I)是一种能够抑制心肌钠通道失活的新型蜘蛛神经毒素,该文结合高效液相色谱与色氨酸荧光测定技术研究了JZTX-I的磷脂膜结合活性。脂质体共沉淀实验表明,JZTX-I具有不依赖于带负电荷磷脂组成的生物膜结合活性。当加入由酸性或中性磷脂构成的脂质体后,JZTX-I能够分别产生6.4和4.7nm的蓝移以及7.4和8.0nm的红移激发漂移,显示JZTX-I能够插入磷脂膜,同时该分子疏水表面的色氨酸残基处于一个运动受限的界面区域。荧光淬灭实验进一步证实,与脂质体结合能够减少该毒素分子表面色氨酸残基的溶剂暴露。该研究结果为阐明JZTX-I的离子通道门控调节机制提供了新的信息。 相似文献
132.
133.
Summary Four most frequently used presentation forms of the ECD response are described. Equations describing the dependence of the
sensitivity, linearity and minimum detectable concentration of the ECD working under constant frequency mode of operation
on the pulse period are derived from Wenthworth’s kinetic model for all four forms mentioned above. The forms presented are
compared on the basis of equations derived. Results of the calculations are given and some predictions are experimentally
tested for sulphur hexafluoride. Good agreement was found between the predicted and observed relationships.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献
134.
高效液相钴离子催化化学发光抑制法测定茶叶中的茶氨酸 总被引:5,自引:0,他引:5
研究了用高效液相分离、抑制化学发光测定茶叶中茶氨酸的分析方法。该法采用YWG C18(10μm,250mm×5 0mmi d )柱,以0 01mol·L-1醋酸钠 醋酸缓冲液(pH5 5)为流动相,流速为0 8mL·min-1。对茶氨酸抑制Co2+催化鲁米诺(luminol)与过氧化氢(H2O2)化学发光反应的条件进行了优化:Co2+的质量浓度为2μg·L-1,鲁米诺浓度为0 25mmol·L-1,H2O2浓度为0 5mmol·L-1。在茶氨酸的质量浓度为0 2g·L-1~5 0g·L-1时,茶氨酸抑制化学发光产生负峰的相对峰面积Y(将实际峰面积缩小至万分之一)与其质量浓度X(kg·L-1)的线性回归方程为Y=33862X+1 0605(r=0 9983)。 相似文献
135.
消毒剂产品中三氯新的测定及其稳定性研究 总被引:9,自引:0,他引:9
采用反相高效液相法测定消毒剂产品中的三氯新。在KromasilC18柱 (2 0 0mm× 4 6mmi d )上 ,以甲醇 乙腈 水 (含 0 0 2mol/LKH2 PO4,pH 2 7) (体积比为 4 0∶4 0∶2 0 )溶液为流动相 ,2 80nm波长下检测 ,样品用流动相超声溶解。三氯新的回收率为 94 2 %~ 10 2 2 % ,相对标准偏差 (RSD)为 2 2 %~ 3 0 %。方法操作简便 ,精密度和准确度高 ,适合三氯新的快速分析。在 5 4℃时保存 14d和 37℃时保存 90d后 ,标准品和样品的含量没有明显变化 ,证明三氯新具有良好的稳定性。 相似文献
136.
万古霉素和替考拉宁都属于糖肽类的大环抗生素,具有立体的环状结构和多个手性中心,是两种常见的手性识别材料,广泛应用于对映体的色谱手性分离分析。该文以万古霉素和替考拉宁为手性选择剂,哌嗪为单体,4,4'-二苯基甲烷二异氰酸酯(MDI)、1,6-己二异氰酸酯(HDI)和2,4-甲苯二异氰酸酯(TDI)为交联剂,通过界面聚合反应形成网状层包裹硅胶载体的方法制得6种高效液相色谱手性固定相,用于分离外消旋化合物,并与MDI直接交联万古霉素和替考拉宁在硅胶表面所得固定相进行了比较。结果表明,利用"网包法"和直接交联法制备的手性柱与商品万古霉素和替考拉宁柱之间具有互补性,均对不同的外消旋体有不同程度的拆分。 相似文献
137.
反相高效液相色谱检测丹参药材中4种丹参酮的含量 总被引:6,自引:0,他引:6
建立了测定丹参药材中4种丹参酮含量的反相高效液相色谱法,色谱条件:流动相为水(含0.5%三乙胺)-甲醇-四氢呋喃(45/55/5,V/V/V),流速为1mL/min;PDA检测波长254m;4种成分丹参酮Ⅰ、丹参酮ⅡA、隐丹参酮和二氢丹参酮的加样回收率在95.1%-101.2%之间,线性范围为0.08-2μg。该方法准确,稳定,重现性好。根据该色谱条件,测定了不同产地的丹参药材,结果表明:该色谱方法准确检测了生药中4种丹参酮的含量,适合于丹参药材的质量控制。 相似文献
138.
Determination of triclosan in foodstuffs 总被引:1,自引:0,他引:1
Sanches-Silva A Sendón-García R López-Hernández J Paseiro-Losada P 《Journal of separation science》2005,28(1):65-72
A reverse-phase high-performance liquid chromatographic (RP-HPLC) method coupled with an ultraviolet detector was developed to determine triclosan which had migrated into foodstuffs from packaging materials. The method includes extraction with hexane, followed by evaporation to dryness and residue re-dissolution in ACN 90%. Chromatographic separation was performed with a Kromasil 100 C18 column (15 cm x 0.4 cm ID, 5 microm particle size) at 30 degrees C and using ACN and water as mobile phases. Regarding recoveries, good results (higher than 83% and lower than 112%) were obtained for the three representative food matrixes selected (orange juice, chicken breast meat, and Gouda cheese). 相似文献
139.
140.
D. Joe Boone 《Accreditation and quality assurance》2004,10(1-2):5-9
A recent US Institute of Medicine report indicated that up to 98,000 deaths and more than 1 million injuries occur each year in the United States due to medical errors. These include diagnostic errors, such as an error or delay in diagnosis, failure to employ indicated tests and the use of outmoded tests. Laboratory tests provide up to 80% of the information used by physicians to make important medical decisions, therefore it is important to determine how often laboratory testing mistakes occur, whether they cause patient harm, where they are most likely to occur in the testing process, and how to prevent them from occurring. A review of the literature and a US Quality Institute Conference in 2003 indicates that errors in laboratory medicine occur most often in the pre-analytical and post-analytical steps in the testing process, but most of the quality improvement efforts focus on improving the analytical process. Measures must be developed and employed to reduce the potential for mistakes in laboratory medicine, including better indicators for the quality of laboratory service. Users of laboratory services must be linked with the laboratorys information system to assist them with decisions about test ordering, patient preparation, and test interpretation. Quality assessment efforts need to be expanded beyond external quality assessment programs to encompass the detection of non-analytical mistakes and improving communication between the users of and providers of laboratory services. The actual number of mistakes in laboratory testing is not fully recognized, because no widespread process is in place to either determine how often mistakes occur or to systematically eliminate sources of error. We also tend to focus on mistakes that result in adverse events, not the near misses that cause no observable harm. The users of laboratory services must become aware of where testing mistakes can occur and actively participate in designing processes to prevent mistakes. Most importantly, healthcare institutions need to adopt a culture of safety, which is implemented at all levels of the organization. This includes establishing closer links between providers of laboratory services and others in the healthcare delivery system. This was the theme of a 2003 Quality Institute Conference aimed at making the laboratory a key partner in patient safety. Plans to create a permanent public–private partnership, called the Institute for Quality in Laboratory Medicine, whose mission is to promote improvements in the use of laboratory tests and laboratory services are underway.Presented at the 9th Conference on Quality in the Spotlight, 18–19 March 2004, Antwerp, Belgium. 相似文献