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1.
A fast, sensitive and reliable ultra performance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS) method has been developed and validated for simultaneous quantitation and pharmacokinetic study of five tanshinones (tanshinone I, tanshinone IIA, tanshinone IIB, dihydrotanshinone I, cryptotanshinone), the bio‐active ingredients of Huo Luo Xiao Ling Dan (HLXLD) in rat plasma. After liquid–liquid extraction, chromatographic separation was accomplished on a Shim‐pack XR‐ODS column (75 × 3.0 mm, 2.2 µm particles) and eluted with a mobile phase consisting of acetonitrile–0.05% formic acid aqueous solution (80:20, v/v) at a flow rate of 0.4 mL/min, and the total run time was 7.0 min. The detection was performed on a triple quadrupole tandem mass spectrometry equipped with an electrospray ionization source in positive ionization and multiple reaction monitoring mode. The lower limits of quantification were 0.050–0.400 ng/mL for all the analytes. Linearity, precision and accuracy, the mean extraction recoveries and matrix effects all satisfied criteria for acceptance. This validated method was successfully applied to a comparative pharmacokinetic study of five bio‐active components in rat plasma after oral administration of HLXLD or Salvia miltiorrhiza extract in normal and arthritic rats. The results showed that there were different pharmacokinetic characteristics among different groups. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
2.
利用矿渣制备微晶玻璃是提高矿产资源利用率的主要形式之一。本文以白云鄂博尾矿为原料,采用微波一步法制备了CaO-MgO-Al2O3-SiO2(CMAS)系辉石相矿渣微晶玻璃。选择835 ℃作为晶化温度,研究了微波加热对微晶玻璃析晶行为和微观组织的影响。以La2O3作为研究变量探讨了La2O3添加对矿渣微晶玻璃析晶行为的作用。与传统的热处理制度相比,微波加热可以在较短的时间内达到较高的析晶效果。同时La2O3的添加促进了晶粒细化。由拉曼光谱分析,La离子添加会导致玻璃网络中桥氧的增多,促进了辉石相析晶。在La的添加量为4%(质量分数)时硬度最高,达到了829.22 MPa。  相似文献   
3.
建立了定量肽段串联体蛋白质(concatamers of Q peptides, QconCATs)结合18O同位素标记-多反应监测质谱的蛋白质绝对定量新方法。首先对QconCAT重组蛋白质进行了纯度表征,十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)表征结果表明重组蛋白质的纯度在99%以上,相对分子质量约为63.4 kDa。对QconCAT重组蛋白质酶切后的肽段混合物进行质谱分析,并经pFind和pLabel软件处理,验证了目标肽段。还考察了QconCAT重组蛋白质的酶切效率和18O标记效率,并对QconCAT蛋白质结合18O标记-同位素稀释-多反应监测质谱方法进行了评价。实验结果表明,采用该方法对腾冲嗜热厌氧菌(Thermoanaerobacter tengcongensis, TTE)中选定蛋白质的肽段进行绝对含量测定时,相对标准偏差小于20%,准确度较高,说明该方法可用于复杂生物样本中蛋白质的绝对定量。更重要的是所建方法不仅解决了细胞培养氨基酸稳定同位素标记(SILAC)技术的重标试剂价格昂贵的问题,也为定量蛋白质组学提供了一种新的方法。  相似文献   
4.
The novel aminoporphyrin‐end‐functionalized poly(N‐isopropylacrylamide) (PNIPAM) polymer H2N‐TPP‐PNIPAM (TPP=5,10,15,20‐tetraphenyl‐21H,23H‐porphyrin) behaves as a multifunctional platform that displays a photodynamic effect, thermosensitivity, and fluorescence properties. The polymer was designed by using an asymmetrical aminoporphyrin (i.e., H2N‐TPP‐Cl) as the initiator for the atom‐transfer radical polymerization of N‐isopropylacrylamide (NIPAM). The polydispersity index (PDI) obtained by gel‐permeation chromatography indicated that the molecular‐weight distribution was narrow (1.09<PDI<1.27). The lower critical solution temperatures of H2N‐TPP‐PNIPAM showed a decreasing trend as the molecular weight was increased as a result of the incorporation of the porphyrin group at the end of the chain. The fluorescence spectra revealed the luminescent properties of the materials. The results of confocal laser scanning microscopy showed that the polymer could enter the cytoplasm through endocytosis. In addition, the multifunctional platform exhibited low toxicity against normal cells (L929) and cancer cells (Hela) and enhanced photodynamic activity towards HeLa cells, without significant necrocytosis towards L929 cells; as a result this material may be useful in the future for practical photodynamic therapy.  相似文献   
5.
Hydrogen sulfide (H2S) is recognized as an endogenous gaseous signaling agent in many biological activities. Lysosomes are the main metabolic site and play a pivotal role in cells. Herein, we designed and synthesized two new fluorescent probes BDP-DNBS and BDP-DNP with a BODIPY core to distinguish H2S. The sensing mechanism is based on the inhibition-recovery of the photo-induced electron transfer (PET) process. Through comparing the responsive behaviors of the two probes toward H2S, BDP-DNBS showed a fast response time (60 s), low limit of detection (LOD, 51 nM), high sensitivity and selectivity. Moreover, the reaction mechanism was demonstrated by mass spectrometry and fluorescence off-on mechanism was proved by density functional theory (DFT). Significantly, confocal fluorescence imaging indicated that BDP-DNBS was successfully used to visualize H2S in lysosomes in living HeLa cells.  相似文献   
6.
针对35kV高温超导可控电抗器,设计开发了一套专门用于监控电抗器工作状态的数据采集系统。根据其工作环境,选择了检测所用探头的种类以及对应的配套设备;根据数据采集本身精准度的要求,完成了数据采集仪器的选型;对探头数量、排布进行了优化选择,针对其发热问题较为严重的部位进行重点监控;利用Lab VIEW设计了一套完整的数据采集人机交互系统。  相似文献   
7.
8.
Cross‐coupling reactions between propargylic alcohols and isocyanides, by means of silver catalysis, have been described. This new reaction is both atom and step efficient and is applicable to a broad scope of substrates, allowing the synthesis of a range of synthetically valuable 2,3‐allenamides in moderate to excellent yields.  相似文献   
9.
建立了金属标记结合高效液相色谱-选择性离子监测质谱(SIM)的蛋白质绝对定量新方法。实验考察了金属标记效率、金属标记的稳定性、标记后肽段的色谱保留和质谱行为、新定量方法的线性范围和准确度。实验结果表明金属标记具有标记效率高,稳定性好,色谱保留行为一致等优点。另外,金属标记-选择离子监测质谱绝对定量方法灵敏度高,其定量限低至1 fmol,线性范围为1~500 fmol,线性范围内R2值大于0.99,具有良好的线性关系;经过测量,标准肽段的回收率为117.01%,说明该方法具有较高的准确度。将该方法应用于腾冲嗜热菌中烯醇酶蛋白的定量分析,相对标准偏差为5.47%,表明该方法的精密度高。以上结果表明该方法可以用于生物样本中的蛋白质的绝对定量分析,为比较简单的生物样本中蛋白质的绝对定量方法提供了一种新的选择。  相似文献   
10.
In order to develop the conversion of heavy oil with a high yield of propylene in the catalytic cracking process, ZSM-5 zeolite was modified by tungsten and phosphorus, which was proved to be an effective method. Characterization results show that the improvement of catalytic performance could be correlated to the interaction of phosphorus and tungsten species on ZSM-5. P inhibited the aggregation of tungsten species on ZSM-5 and was conductive to convert the tungsten species with octahedral coordination into tetrahedral coordination. And this ultimately led to that more acid sites were reserved after hydrothermal treatment in the tungsten and phosphorus co-modified ZSM-5 catalyst. Phosphorus species played an important role to restrain the dehydrogenation activity of tungsten. In addition, a model reflecting the interaction between tungsten species and ZSM-5 framework was proposed.  相似文献   
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