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81.
82.
G. K. Poon P. Mistry F. I. Raynaud K. R. Harrap B. A. Murrer C. F. J. Barnard 《Journal of pharmaceutical and biomedical analysis》1995,13(12):1493-1498
The present study describes the application of on-line liquid chromatography-electrospray ionisation in conjunction with a high resolution magnetic sector mass spectrometer to identify metabolites of a platinum(IV) anticancer drug JM216 bis(acetato)amminedichloro(cyclohexylamine)platinum(IV)] in human plasma. Four metabolites were identified following incubation of JM216 in human plasma: JM118 [amminedichlorocyclohexylamineplatinum(II)], a platinum(II) complex; JM383 [bis(acetato)amminedihydroxo(cyclohexylamine)platinum(IV)]; JM518 [bis(acetato)amminechloro(cyclohexylamine)hydroxoplatinum(IV)] and its isomer JM559. The platinum complexes mass spectra were dominated by the natriated [M + Na]+ ion. Elemental compositions of these natriated ions were confirmed by accurate mass measurement on a magnetic sector mass spectrometer in the course of LC/MS analysis. This study demonstrates the capability of direct LC-ESI/MS with accurate mass measurement for analysis of platinum complexes in biological samples. Our results suggest that LC-ESI/MS is a powerful technique for structure elucidation of novel metabolites, and could make valuable contributions to drug metabolism research. 相似文献
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85.
Alpha-glucosidase activity and sperm motility 总被引:2,自引:0,他引:2
We correlated the activity of alpha-glucosidase in seminal plasma with the motility and differential motility of sperm. Significant positive correlations were found between the alpha-glucosidase activity and both motility and the percentage sperm with good forward progression. This supports the use of alpha-glucosidase in semen as a marker of epididymal function and specifically of the development of motility. 相似文献
86.
Jin Hui-ming 《华中科技大学学报(医学英德文版)》1990,10(4):193-200
Summary The content of plasma fibronectin and tissue extractable fibronectin in normal rats was measured with rocket immunoelectrophoresis
and ELISA in the present study. The difference in tissue fibronectin distribution in various organs and the correlation between
distribution and content of fibronectin have been studied. We suggest that tissue fibronectin may be a complex component.
The change in plasma fibronectin reflects a dynamic balance existing between the tissue fibronectin pool and plasma fibronectin
pool in normal rats. Plasma fibronectin and tissue fibronectin concentrations are not static, and they can only be maintained
in a relatively stable state in normal rats. 相似文献
87.
高效液相色谱法测定微量耳血中头孢他定的浓度 总被引:2,自引:0,他引:2
本文介绍采取微量耳血以高效液相色谱法测定头孢他定(Ceftazidime)的血药浓度。血样经6%高氯酸沉淀蛋白,流动相为含25%甲醇的0.05mol/L醋酸铵溶液,以冰醋酸调节pH值至4~5,检测波长为254nm,内标物为头孢唑啉(Cefazolin)。经对家兔采取微量耳血测定其血药浓度,可知头孢他定为二室模型,T_1/2α为0.18±0.05h,T_1/2β为1.75±0.07h。并对3名住院病人静脉注射1g头孢他定后定时分别取微量耳血进行分析,所得结果与文献基本一致。本文方法简便、快速,结果令人满意。 相似文献
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89.
J. W. P. GOVERS-RIEMSLAG M. SMID J. A. COOPER† K. A. BAUER‡ R. D. ROSENBERG‡ C. E. HACK§ K. HAMULYAK¶ H. M. H. SPRONK G. J. MILLER† H. TEN CATE 《Journal of thrombosis and haemostasis》2007,5(9):1896-1903
BACKGROUND: The plasma kallikrein-kinin system (PKKS) has been implicated in cardiovascular disease, but activation of the PKKS has not been directly probed in individuals at risk of coronary heart disease (CHD) or stroke. OBJECTIVE: To determine the involvement of the PKKS, including factor XI, in cardiovascular disease occurring in a nested case-control study from the Second Northwick Park Heart Study (NPHS-II). METHODS AND RESULTS: After a median follow-up of 10.7 years, 287 cases of CHD and stroke had been recorded and 542 age-matched controls were selected. When FXIIa-C1 esterase inhibitor (C1-inhibitor) concentrations were divided into tertiles (lowest tertile as reference), the odds ratios (ORs) at 95% CIs for CHD were 0.52 (0.34-0.80) in the middle tertile and 0.73 (0.49-1.09) in the highest tertile (P = 0.01 for the overall difference; P = 0.01 for CHD and stroke combined). For kallikrein-C1-inhibitor complexes, the ORs for stroke were 0.29 (0.12-0.72) and 0.67 (0.30-1.52) in the middle and high tertiles, respectively (P = 0.02). FXIIa-C1-inhibitor and kallikrein-C1-inhibitor complexes were negatively related to smoking and fibrinogen (P < 0.005). FXIa-inhibitor complexes correlated strongly with FXIIa-inhibitor complexes. CONCLUSIONS: Lower levels of inhibitory complexes of the PKKS enzymes and particularly of FXIIa contribute to the risk of CHD and stroke in middle-aged men. This observation supports the involvement of the PKKS in atherothrombosis. 相似文献
90.
目的为了初步了解男性精浆中的蛋白电泳谱以及蛋白谱与男性生育能力的相关关系。方法通过应用SPIFE3000全自动电泳分析仪对20例对照组(生育组)与140例观察组(不育组)的精浆进行蛋白分离(琼脂糖区带电泳法),建立其精浆蛋白质的特征电泳图谱,并进行对比分析。结果精浆蛋白经酸蓝染色后,区带清晰,从阳极到阴极分为A、B、C、D、E 5条带,电泳各区带百分比含量结果经方差分析,发现不育组与生育组A、C、D、E百分比含量变化有统计学意义(P<0.01),且无精子症患者精浆的蛋白谱有特异的"双峰"特点。结论精浆蛋白区带电泳分析可作为不育症的辅助诊断指标,且将是对男性不育诊断手段的有力补充。 相似文献