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61.
62.
Pavan Kumar Prathipati Subhra Mandal Christopher J. Destache 《Biomedical chromatography : BMC》2019,33(2)
A sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed and validated for quantification of bictegravir in human plasma. A small volume of only 50 μL aliquot of plasma was precipitated with acetonitrile containing an internal standard (IS). Chromatographic separation was performed on a Kinetex EVO C18 column, 50 × 3.0 mm, 5 μm using an isocratic mobile phase containing 80:20 acetonitrile–water with 0.1% formic acid. A mass spectrometer was operated in ESI positive multiple reaction monitoring mode using the m/z 450.1/289.1 for bictegravir and 420.1/277.1 for IS. The dynamic range of the method was 1–10,000 ng/mL with a correlation coefficient of ≥0.9991. The precision results of calibration standards were in the range of 0.05–4.57% and accuracies were 95.07–104.70%. The mean extraction recovery was 98.64% with a precision of 2.91%. The method was validated as per US Food and Drug Administration guidelines and was found to be accurate and precise. The method was successfully applied to in vitro cellular uptake study. 相似文献
63.
Gisele Luiza Pavan Igor Tadeu Lazzarotto Bresolin Aline Ferreira Velho Muzio Daniele Celestino Cunha Sonia Maria Alves Bueno 《Biomedical chromatography : BMC》2019,33(1)
The behavior of human immunoglobulin G (IgG) and antigen‐binding fragment (Fab fragment) adsorption onto phospho‐l ‐tyrosine immobilized on agarose (P‐Tyr‐agarose) was evaluated by pseudoaffinity chromatography. The effects of buffer systems MES, MOPS, Bis–Tris, Tris–HCl and sodium phosphate (NaP) and pH on IgG adsorption were studied and high purity values were obtained (96%, based on ELISA analysis of albumin, transferrin and immunoglobulins A, G and M) when IgG was purified from human plasma diluted in 10 mmol L?1 NaP buffer at pH 6.0. The capture of IgG by the P‐Tyr‐agarose was also promising, since 91% of the IgG was adsorbed when plasma was diluted in 25 mmol L?1 MES buffer at pH 5.5, recommending its use for IgG depletion from human plasma under this condition. The experimental data on IgG adsorption kinetics were in agreement with the pseudo‐second‐order model. The adsorption isotherm data were well described by the Langmuir–Freundlich model with the value of parameter n being <1 (0.72), indicating negative cooperativity. Selectivity was achieved on P‐Tyr‐agarose from digested human IgG in HEPES 25 mmol L?1 buffer at pH 7.0 where Fab fragments were obtained in eluted fractions without Fc fragments (but with uncleaved IgG) with 86.2% recovery. 相似文献
64.
Let G be a unipotent algebraic subgroup of some defined over . We describe an algorithm for finding a finite set of generators of the subgroup . This is based on a new proof of the result (in more general form due to Borel and Harish-Chandra) that such a finite generating set exists. 相似文献
65.
66.
Non-static plane symmetric cosmological solutions are studied with zero mass scalar fields in the context of cosmic strings
in general relativity. Some physical and geometrical features of these models are discussed. 相似文献
67.
Antonyraj Arockiasamy Randall M. German Paul Wang Mark F. Horstemeyer Pavan Suri S. J. Park 《Journal of Thermal Analysis and Calorimetry》2010,100(1):361-366
Differential scanning calorimetry (DSC) is a powerful technique that measures the heat evolution from a sample under a controlled
condition and studies the phase transformation, precipitation, and dissolution activities. In this work, we investigated the
influence of admixed silicon and silicon carbide and the effect of different atmospheres on the heat flow properties and microstructure
of atomized Al6061 powder using DSC and scanning electron microscopy. The DSC analysis revealed the addition of silicon considerably
decreased the temperature of first endothermic peaks. With an increase in silicon content the enthalpy for the first endothermic
peak increased, whereas the second endothermic peak decreased. An endothermic peak, indicating the formation of AlN, was observed
for powders without the silicon addition, but was noticeably absent in the case of alloys with Si addition. The SiC addition
has no influence on changing the enthalpy of the systems we investigated. The reason for this behavior is analyzed and presented
in this article. 相似文献
68.
F. Brandolini M. De Poli P. Pavan R.V. Ribas D. Bazzacco C.R. Rossi-Alvarez 《The European Physical Journal A - Hadrons and Nuclei》1999,6(2):149-155
The g-factors of some members of the ground state band and of the 2+ state in the %-vibrational band have been measured in 160,162,164Dy using the Coulomb Excitation Transient Field technique, induced by 58Ni projectiles at 230, 210 and 217 MeV, respectively. The g-factors in the ground state band are consistent with a constant value, while that of the 2+% states is about 20% larger in average than those in the ground state band. Results are discussed in the frame of the systematics in this nuclear region. 相似文献
69.
70.
Magnetic properties of glucose coated cuprous oxide nanoparticles of different sizes have been studied. Unlike bulk Cu2O, which shows diamagnetic behavior, the nanoparticles show superparamagnetic behavior. A superparamagnetic blocking temperature of 21 K is observed for 5 nm particles. A magnetic hysteresis loop with a coercivity of 406 Oe is observed for these particles at 5 K. The magnetization and the coercivity increase with decreasing particle size. The superparamagnetic behavior, along with the increase in magnetization and coercivity with decreasing particle size, is due to the enhanced surface contributions to the magnetism. 相似文献