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141.
WANG An-bao~ * Joseph F. Foss YUAN Chun-su Joachim Osinski . Department of Anesthesia Critical Care The University of Chicago Chicago IL USA . Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai P. R. China 《高等学校化学研究》2005,21(3):268-273
Introduction Opioidmedicationsarewidelyusedclinically forrelievingpainandasantidiarrhealsandantitus- sives.Opioidantagonistsconsistofagroupofnat- ural,semisynthetic,orsyntheticcompoundsacting onaseriesofreceptors.Concomitantwiththeabil- itytorelievepain,thesedrugshaveadverseef- fects.Side-effectsofopioidtreatmentincludenau- sea,constipation,urinaryretention,pruritus,fa- tigue,psychomimeticdisturbance,difficultmic- turition,vomitinganddependence.Thesesideef- fectsareoftensevereenoughtolimitthe… 相似文献
142.
The interaction of bromothymol blue(BB) with human serum albumin(HSA) was studied by electrochemical techniques and a sensitive method for proteins assay was developed. When BB interacted with HSA, the voltammetric peak current value of BB decreased linearly with the concentration of HSA in a range of 1.0--40.0 mg/L, and the peak potential shifted negatively. Based on the results, a sensitive assay method for proteins, such as HSA, bovine serum albumin(BSA), and egg albumin etc. was established. This method was further applied to determining the HSA in healthy human blood samples, and the results are not significantly different from those obtained by the classic Coomassie Brilliant Blue G-250 spectrophotometic method. The detecting conditions of this method were optimized and the interaction mechanism was discussed. The results show that the electrochemical parameters(formal potential E^0, standard rate constant of the electrode reaction ks, parameter of kinetic nα) of BB have no obvious changes before and after the interaction, which indicate that BB can interact with HSA, forming an electrochemical non-active complex. The equilibrium constant(βs) and the binding ratio(m) for this complex were calculated. The m is 4 and βs is 1.41 × 10^19. This method is fast, simple, highly sensitive, and has good selectivity, which can be used in clinical measurements. 相似文献
143.
Unique block co-polymer P(MAn-St-NIPAm) has been successfully synthesized by reversible addition fragmentation chain transfer radical polymerization protocol. Based on the tunable hydrophobic/hydrophilic properties of the block co-polymer, a new open tubular capillary electrochromatography (OT-CEC) system has been constructed with the prepared block co-polymer as the coating and applied in analysis of β-lactam antibiotics in serum samples. 相似文献
144.
ICP-AES法测定人血清中的硒 总被引:6,自引:0,他引:6
采用消化法预处理血清样品 ,并用ICP AES法测定样品中的Se ,同时 ,探索Fe的存在对测定的干扰情况以及干扰的消除方法。结果表明 ,Se的检测限为 0 0 0 76μg·mL- 1 ,加标回收率为 91 6 % ,1 0次测定的RSD(n =1 0 )为 2 1 4 7% ;在样品中加入KOH ,可以大大降低Fe对Se测定的干扰。 相似文献
145.
选取包头市区正常产妇68名及其所生新生儿作为研究对象。分娩后抽取产妇肘静脉血及新生儿脐动脉血,分析其血清中铁、锌、铜、硒的含量.研究结果揭示:新生儿脐带血清中铁、铜、硒的含量均高于产妇血清中的含量,铁与铜有显著性差异(P<0.05),硒的差异不显著(P>0.05);而锌则相反,新生儿脐带血清中的含量低于产妇血清中的含量,二者有高度显著性差异(P<0.01)。产妇血清中Fe/Zn、Cu/Zn、Se/Zn比值分别为3.83、2.78、0.08;而新生儿脐带血清中Fe/Zn、Cu/Zn、Se/Zn比值则各为9.56、6.80、0.19,进一步说明新生儿脐带血清中的锌含量降低,其它元素含量增加。 相似文献
146.
合成了一种新型的甘油三酯吸附剂-磺化羟乙基化交联壳聚糖,用其对血浆中甘油三酯进行吸附.实验结果表明,该吸附剂最高可使血清中的甘油三酯降低76.9%(每克树脂吸附量为6.25mg),而对血清中总蛋白(TP)的吸附较少. 相似文献
147.
建立了血清中假尿苷含量的高效液相色谱测定法。结果表明,假尿苷在0375~12μmol/L范围内线性关系良好。最低检测量为0015μmol/L,回收率为927%,日内和日间相对标准偏差(RSD)分别为42%和47%。用该法测定正常人及肝癌、肺癌、食管癌患者血清中假尿苷含量发现,3种肿瘤患者血清中假尿苷含量明显高于正常人(P<005),说明血清假尿苷可作为诊断恶性肿瘤的一种标志物。 相似文献
148.
《中国化学快报》2019,30(9):1627-1630
With d-proline as the reducing and capping agent, fluorescent gold nanoclusters were rapidly prepared (d-Pro@AuNCs) within 10 min at 100 °C. In the present of gold nanoparticles, the fluorescence of d-Pro@AuNCs was remarkably quenched. Interestingly, based on the electrostatic interaction between anticancer drug Raltitrexed and gold nanoparticles induced fluorescence “turn-on” principle, a high selective assay for detection of Raltitrexed was established with the probe associating the fluorescence emission at 435 nm. The fluorescence intensity of d-Pro@AuNCs linearly correlated with the concentration of Raltitrexed in the range from 5.0 μmol/L to 40.0 μmol/L (R2 = 0.999) and the limit of detection was 1.9 μmol/L. Further, after Raltitrexed was abdominal injected in rats, a metabolic approach was constructed with the prepared fluorescent probe. It showed great potential of AuNCs-based sensing probes for application in analysis of serum anticancer drugs. 相似文献
149.
A new competitive enzyme-linked immunosorbent assay (ELISA) for determination of estrogenic bisphenols 总被引:8,自引:0,他引:8
Bisphenol A and other hydroxylated diphenylalkanes (generally known as bisphenols) have been identified as potential estrogenic substances. In this paper, a specific polyclonal antibody was produced against these compounds by immunization of rabbits with a conjugate of 4,4-bis (4-hydroxyphenyl) valeric acid and bovine serum albumin (BHPVA-BSA). The polyclonal antibody showed specific recognition of the bisphenol structure, while the cross reactions of other common phenolic compounds such as phenol, hydroquinol and p-hydroxybenzoic acid were all lower than 1%. The linear range of bisphenol A calibration curve was 1–10 000 ng ml−1. Real water samples and mouse serum samples were spiked with known amount of bisphenol A and measured by the competitive ELISA. Recoveries were between 92 and 105%. The detection limits were found to be 0.1 ng ml−1 for real water samples and 2 ng ml−1 for serum samples. The method is very useful for monitoring bisphenol compounds in environmental and biological samples. 相似文献
150.
C. A. M. Meijers J. A. R. J. Hulsman und J. F. K. Huber 《Fresenius' Journal of Analytical Chemistry》1972,261(4-5):347-353
Zusammenfassung Die Prinzipien für die Optimierung einer chromatographischen Trennung in bezug auf Auflösung und Verdünnung werden auf die Trennung von Corticosteroid und Cortisol angewandt. Unter den bei der Optimierung gefundenen Bedingungen erfolgt die Trennung in weniger als 4 min. Mit einem rauscharmen spektrophotometrischen Detektor können 8,5 ng Cortisol mit einer Präzision von 20% und 100 ng mit einer Präzision von 3,3% bestimmt werden. Bei der Bestimmung in Serum wird Cortisol zuerst mit Dichlormethan extrahiert. Die Vollständigkeit der Extraktion wurde chromatographisch bestätigt.
Determination of cortisol in serum by the use of column liquid chromatography
The principles for the optimization of chromatographic separations with respect to resolution and dilution are applied to the separation of corticosteroid and cortisol. Under the conditions found at the optimization the separation is performed in less than 4 min. With a low-noise spectrophotometric detector 8.5 ng of cortisol can be determined with a precision of 20% and 100 ng with a precision of 3.3%. For the determination in serum cortisol is extracted first by the use of dichloromethane. The complete extraction was confirmed chromatographically.相似文献