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111.
Hongjun Xia Xiaodan WangLi Li Shengjia WangChangchuan Guo Yao LiuLushan Yu Huidi JiangSu Zeng 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(28):2701-2706
A highly sensitive HPLC–ESI-MS method has been developed and validated for the quantification of ginkgolic acid (15:1) in a small quantity of rat plasma (50 μL) using its homologous compound ginkgolic acid (17:1) as an internal standard. GA (15:1) and GA (17:1) were extracted from biological matrix by direct protein precipitation with 5-fold volume of methanol and separated on an Elite hypersil BDS C18 column (2.1 × 100 mm, 3 μm), eluted with acetonitrile:water (92:8, v/v, containing 0.3% glacial acetic acid). Linear range was 8–1000 ng/mL with the square regression coefficient (r2) of 0.996. The lowest concentration (8 ng/mL) in the calibration curve was estimated as LLOQ with both deviation of accuracy and RSD of precision <20% (n = 6). The intra- and inter-day precision ranged from 3.6% to 9.9%, and the intra- and inter-day accuracy was between 89.9% and 101.3%. This method was successfully applied to study pharmacokinetics of GA (15:1) in rats after oral administration at a dose of 10 mg/kg. GA (15:1) pharmacokinetic parameters Cmax, Tmax, t1/2, AUC0–12h are 1552.9 ± 241.0 ng/mL, 0.9 ± 0.7 h, 5.5 ± 2.6 h, 3356.0 ± 795.3 ng h/mL, respectively. 相似文献
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Jing Zhang Yang Zhou Youjun Wu Lin Ma Yingying Fan Xuan Kang Hongjun Shi Jun Zhang 《Biological trace element research》2012,150(1-3):258-263
Noncoding RNAs have drawn significant attention in carcinogenesis. In this study, we identified a novel gene named nickel-related gene1 (NRG1) associated with nickel-induced cancer. By using rapid amplification of cDNA end PCR, we obtained the full length of the cDNA. The sequence was analyzed by using related bioinformatics software and comparative genomics methods. The results showed that NRG1 was located on chromosome 2q12, within intron2 of ADAMTS6, a disintegrin and metalloproteinase with thrombospondin motifs. And, NRG1 had a high level of homology (76?%) to rat LINE1 sequence RL1.3 (long interspersed middle repetitive DNA). What's more, there was no continuous open reading frame present in NRG1 sequence. Taken together, these data demonstrate that NRG1 is a novel noncoding RNA, and we predicted it may be a transposon-like gene. The identification of NRG1 emphasized the potential role of noncoding RNA in nickel carcinogenesis. 相似文献
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Siddiqui S Dai Z Stavis CJ Zeng H Moldovan N Hamers RJ Carlisle JA Arumugam PU 《Biosensors & bioelectronics》2012,35(1):284-290
It is well recognized that label-free biosensors are the only class of sensors that can rapidly detect antigens in real-time and provide remote environmental monitoring and point-of-care diagnosis that is low-cost, specific, and sensitive. Electrical impedance spectroscopy (EIS) based label-free biosensors have been used to detect a wide variety of antigens including bacteria, viruses, DNA, and proteins due to the simplicity of their detection technique. However, their commercial development has been hindered due to difficulty in interpreting the change in impedance upon antigen binding and poor signal reproducibility as a result of surface fouling and non-specific binding. In this study, we develop a circuit model to adequately describe the physical changes at bio functionalized surface and provide an understanding of the detection mechanism based on electron exchange between electrolyte and surface through pores surrounding antibody-antigen. The model was successfully applied to extract quantitative information about the bio surface at different stages of surface functionalization. Further, we demonstrate boron-doped ultrananocrystalline diamond (UNCD) microelectrode array (3 × 3 format, 200 μm diameter) improves signal reproducibility significantly and increases sensitivity by four orders of magnitude. This study marks the first demonstration of UNCD array based biosensor that can reliably detect a model Escherichia coli K12 bacterium using EIS, positioning this technology for rapid adoption in point-of-use applications. 相似文献
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对南海西沙海槽111PC孔沉积物中的硅藻化石研究表明,硅藻以热带、亚热带浮游性种类和近岸性种类为主,可划分出6个硅藻组合带,大体对应于浮游有孔虫氧同位素6个期次。结合有地层对比意义的属种及组合,建立了里斯冰期以来本孔的硅藻生物地层框架。硅藻丰度、属种组合变化指示海区气候经历了冰期-间冰期气候旋回及不稳定性波动。晚玉木冰期硅藻丰度高,冰后期、中玉木冰期次之,里斯冰期至早玉木冰期丰度较低,这与南海西南部不同,与南海东北相似但也不尽相同。里斯冰期至里斯玉木间冰期转换阶段,硅藻属种对气候变暖的反应较快。硅藻属种特征显示中玉木冰期气候为弱暖期,且有早晚两个暖湿阶段。硅藻属种的不连续分布也表明沉积环境在部分时段极不稳定。 相似文献
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