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排序方式: 共有4669条查询结果,搜索用时 302 毫秒
1.
Jia Yang Xingang Li Wenjun Li Xin Xi Qian Du Feng Pan Songqing Liu 《Biomedical chromatography : BMC》2020,34(8):e4857
Because of its unpredictable side effects and efficacy, the anticancer drug docetaxel (DTX) requires improved characterisation of its pharmacokinetic profiles through population pharmacokinetic studies. A sensitive and rugged LC–MS/MS method for the detection of DTX in human plasma was developed and optimised using paclitaxel as an internal standard (IS). The plasma samples underwent rapid extraction using hybrid solid-phase extraction-protein precipitation. The analyte and IS were separated with an isocratic system on a Zorbax Eclipse Plus C18 column using water containing 0.05% acetic acid along with 20 μM of sodium acetate and methanol (30/70, v/v) as the mobile phase. Quantification was performed using a triple quadrupole mass spectrometer through multiple reaction monitoring in positive mode, using the m/z 830.3 → 548.8 and m/z 876.3 → 307.7 transitions for DTX and paclitaxel, respectively. The range of the calibration curve was 1–500 ng/mL for DTX, and the linear correlation coefficient was >0.99. The accuracies ranged from −4.6 to 4.2%, and the precision was no higher than 7.0% for the analytes. No significant matrix effect was observed. Both DTX and the IS showed considerable recovery. This method was finally applied to the establishment of a population pharmacokinetic model to optimise the clinical use of DTX. 相似文献
2.
Prof. Dr. Frank Glorius 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8047-8051
A general and efficient methodology for the direct transition metal free trifluoromethylthiolation of a broad range of biologically relevant N‐heteroarenes is reported employing abundant sodium chloride as the catalyst. This method is operationally simple, exhibits high functional group tolerance, and does not require protecting groups. 相似文献
3.
The γcmc values of CTAB-SDS decrease from 63.67 mN/m at 10‡C to 36.38 mN/m at 90‡C, slightly lower than those of either CTAB or SDS.
Correspondingly, the CMC of CTAB-SDS decreases almost by half. The increase of surface activity of CTAB-SDS can be attributed
to the relatively weak electrostatic interaction at high temperature, which is supported by the increase of solubility of
CTAB-SDS with rise in temperature. Catalytic effect on oxidation of toluene derivatives with potassium permanganate follows
the order CTAB-SDS > SDS > CTAB. This is not caused by the dissociative effect of CTAB-SDS with low surface activity at low
temperature, as seen from the fact that almost all oxidative products can be retrieved for different toluene derivatives and
surfactants by mimicking the conditions of reaction. In the emulsifications of toluene derivatives at 90‡C, the time that
turbid water layers of surfactant solutions take to become clear is the same as that of the catalytic effect on oxidation
of toluene derivatives. Thus, it can be inferred that surfactants can improve the oxidation yields of toluene derivatives
by increasing the contact between two reacting phases. 相似文献
4.
5.
Phase Relations and Sodium Ion Conductivity within the Quasi-binary System Na2SiF6/Na2AIF6 . The phase diagram of the Na2SiF6/Na3AlF6 system has been determined by means of x-ray powder diffraction, thermal analysis and conductivity measurements in the sub-solidus region. Na3AlF6 accomodates up to 73 mol.-% Na2SiF6 maintaining the crystal structure type. The sodium ion conductivity increases by about five orders of magnitude upon doping Na3AlF6 with Na2SiF6. 相似文献
6.
双氯芬酸钠与牛血清白蛋白结合反应的特征 总被引:2,自引:0,他引:2
在模拟人体生理条件下,采用荧光光谱和紫外 可见吸收光谱法研究了双氯芬酸钠与牛血清白蛋白的结合反应.实验结果显示,双氯芬酸钠对牛血清白蛋白有较强的荧光猝灭作用,该猝灭过程主要为静态荧光猝灭过程;二者结合常数KLB=2.167×105mol·L-1;二者的结合位置距212位色氨酸2.13nm;同时,由结合反应的热力学参数得出二者作用力主要是氢键或VanderWall's力. 相似文献
7.
高的氢压和反应温度有利于片硼酸钠与镁和氢反应生成硼氢化钠,但温度接近镁的熔点时不利于硼氢化钠的生成。在反应物中添加铁、镍和钴将加速硼氢化钠的生成,而铜的加入却阻碍硼氢化钠的生成。 相似文献
8.
目的:观察隔山消水提物处理牙釉质龋后的表面形态.方法:利用扫描电镜观察隔山消水提物、五倍子水提物、氟化钠、去离子水处理人工釉质龋后脱矿釉质表面沉积物的再矿化效果.结果:经隔山消组处理后的釉质块表面有紧密均匀的结晶区,五倍予处理后的釉质块有明显的结晶颗粒,氟化钠有紧密均匀的矿物沉淀,去离子水处理的釉质表面成疏松状结构.结论:隔山消水提物有再矿化作用,五倍子的再矿化作用强于隔山消. 相似文献
9.
Jun‐Hwan Ahn Choon‐Hwa Lee Yeong‐Deuk Shin Jae‐Suk Lee 《Journal of polymer science. Part A, Polymer chemistry》2004,42(4):933-940
To study living anionic polymerization, 3‐(triethylsilyl)propyl isocyanate (TEtSPI) monomer was synthesized by hydrosilylation of allylamine with triethylsilane and treatment of the resulting amine with triphosgene. The polymerization of TEtSPI was performed with sodium naphthalenide (Na‐Naph) as an initiator and in the absence and presence of sodium tetraphenylborate (NaBPh4) as an additive in tetrahydrofuran (THF) at ?78 and at ?98 °C. A highly stabilized amidate anion for living polymerization of isocyanates was generated for the first time with the combined effect of the bulky substituent and the shielding action of the additive NaBPh4, extending the living character at least up to 120 min at ?98 °C. Even the anion could exist at ?78 °C for 10 min. A block copolymer, poly(n‐hexyl isocyanate)‐b‐poly[(3‐triethylsilyl)propyl isocyanate]‐b‐poly(n‐hexyl isocyanate), was synthesized with quantitative yields and controlled molecular weights via living anionic polymerization in THF at ?78 °C for TEtSPI and ?98 °C for n‐hexyl isocyanate, respectively, with Na‐Naph with three times of NaBPh4 as a common ion salt. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 933–940, 2004 相似文献
10.
Madhuchhanda Maiti Susmita Sadhu Anil K. Bhowmick 《Journal of Polymer Science.Polymer Physics》2004,42(24):4489-4502
In this work, preparation and properties of different nanoclays modified by organic amines (octadecyl amine, a primary amine, and hexadecyltrimethylammonium bromide, a tertiary amine) and brominated polyisobutylene‐co‐paramethylstyrene (BIMS)‐clay nanocomposites are reported. The clays and the rubber nanocomposites have been characterized with the help of Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X‐ray diffraction (XRD). The X‐ray diffraction peaks observed in the range of 3 °–10 ° for the modified clays disappear in the rubber nanocomposites. TEM photographs show predominantly exfoliation of the clays in the range of 12 ± 4 nm in the BIMS. In the FTIR spectra of the nanocomposites, there are common peaks of virgin rubber as well as those of the clays. Excellent improvement in mechanical properties like tensile strength, elongation at break, and modulus is observed on incorporation of the nanoclays in the BIMS. Structure‐property correlation in the above nanocomposites is attempted. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4489–4502, 2004 相似文献