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51.
Sharma K Kandaswamy M Mithra C Meena AK Giri S Rajagopal S Mullangi R 《Biomedical chromatography : BMC》2012,26(2):247-255
A highly sensitive and specific LC-MS/MS-ESI method was developed for simultaneous quantification of albenadazole (ABZ) and ricobendazole (RBZ) in rat plasma (50 μL) using phenacetin as an internal standard (IS). Simple protein precipitation was used to extract ABZ and RBZ from rat plasma. The chromatographic resolution of ABZ, RBZ and IS was achieved with a mobile phase consisting of 5 m m ammonium acetate (pH 6) and acetonitrile (20:80, v/v) at a flow rate of 1 mL/min on a Chromolith RP-18e column. The total chromatographic run time was 3.5 min and the elution of ABZ, RBZ and IS occurred at 1.66, 1.50 and 1.59 min, respectively. A linear response function was established for the ranges of concentrations 2.01-2007 and 6.02-6020 ng/mL for ABZ and RBZ, respectively. The intra- and inter-day precision values for ABZ and RBZ met the acceptance as per FDA guidelines. ABZ and RBZ were stable in battery of stability studies, viz. bench-top, auto-sampler and freeze-thaw cycles. The developed assay was applied to a pharmacokinetic study in rats. 相似文献
52.
This paper studies the asymptotic behavior of the minimum Hellinger distance estimator of the underlying parameter in a supercritical branching process whose offspring distribution is known to belong to a parametric family. This estimator is shown to be asymptotically normal, efficient at the true model and robust against gross errors. These extend the results of Beran (Ann. Statist. 5, 445–463 (1977)) from an i.i.d., continuous setup to a dependent, discrete setup. 相似文献
53.
K. C. Kumara Swamy Sudha Kumaraswamy 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(10):1147-1148
The six-membered phosphorinane ring in (1,4,7,10,13,16-hexaoxacyclooctadecane)potassium 2-O-benzoyl-1,3,5-O-methylidyne-myo-inositol 4,6-cyclophosphate trihydrate, [K(C12H24O6)](C14H12O9P)·3H2O, has a boat rather than a chair conformation. The K+ ion is eight-coordinate and is connected to one of the phosphate O atoms, one of the O atoms of the myo-inositol residue and the six O atoms of the crown ether. 相似文献
54.
Dr. Sinan Wang Dr. David E. Korenchan Paola M. Perez Dr. Céline Taglang Dr. Thomas R. Hayes Dr. Renuka Sriram Dr. Robert Bok Andrew S. Hong Yunkou Wu Henry Li Prof. Zhen Wang Prof. John Kurhanewicz Prof. David M. Wilson Prof. Robert R. Flavell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(51):11842-11846
Alterations in Zn2+ concentration are seen in normal tissues and in disease states, and for this reason imaging of Zn2+ is an area of active investigation. Herein, enriched [1-13C]cysteine and [1-13C2]iminodiacetic acid were developed as Zn2+-specific imaging probes using hyperpolarized 13C magnetic resonance spectroscopy. [1-13C]cysteine was used to accurately quantify Zn2+ in complex biological mixtures. These sensors can be employed to detect Zn2+ via imaging mechanisms including changes in 13C chemical shift, resonance linewidth, or T1. 相似文献
55.
A dual field grating has been introduced for use in Talbot interferometry. We report here results of an experimental investigation on setting sensitivity when using these gratings for testing. 相似文献
56.
Srinivas Nanduri Vijay Kumar Nyavanandi Mahendar Velisoju Sriram Rajagopal R Rajagopalan 《Tetrahedron letters》2004,45(25):4883-4886
Andrographolide 1, the major constituent of the Indian medicinal plant Andrographis paniculata (Acanthaceae) was converted into the key intermediate 4 by selective oxidative degradation of the C-12,13 olefin bond. The aldehyde functional group present in 4 has been utilized for synthesizing a number of structurally diverse labdane diterpenes. Synthesis and in vitro cytotoxic activity results of the compounds prepared are discussed. 相似文献
57.
Chakravarty PK Tyagarajan S Shih TL Salva S Snedden C Wyvratt MJ Fisher MH Meinke PT 《Organic letters》2002,4(8):1291-1294
An efficient synthesis of the truncated 3"-aldehyde (3) from nodulisporic acid A (1) under mild conditions is described. Further oxidation of 3 to 3"-carboxylic acid (4) and its subsequent oxidative degradation produced 1"-aldehyde (5). These new derivatives are versatile intermediates for the preparation of new, side chain modified derivatives of nodulisporic acid A. [reaction: see text] 相似文献
58.
59.
Saurabh Usgaonkar Subrajeet Deshmukh Bipul Biswas Neeta Karjule Prashant Yadav Jayaraj Nithyanandhan Guruswamy Kumaraswamy 《Angewandte Chemie (International ed. in English)》2019,58(9):2715-2719
It is of immense interest to exert spatial and temporal control of chemical reactions. It is now demonstrated that irradiation can trigger reactions specifically at the surface of a simple colloidal construct, obtained by adsorbing polyethyleneimine on fluorescent colloidal particles. Exciting the fluorescent dye in the colloid affords photoinduced electron transfer to spatially proximal amine groups on the adsorbed polymer to form free radical ions. It is demonstrated that these can be harnessed to polymerize acrylic acid monomer at the particle surface, or to break up colloidal assemblies by cleaving a cross‐linked polymer mesh. Formation of free radical ions is not a function of the size of the colloid, neither is it restricted to a specific fluorophore. Fluorophores with redox potentials that allow photoinduced electron transfer with amine groups show formation of free radical ions. 相似文献
60.
Numerical simulation of nonlinear waves to reproduce the laboratory measurements has been a topic of great interest in the recent past. The results reported in the literature are mainly focused on qualitative comparison or on the relative errors between the numerical simulation and measurements in laboratory and hence lack in revealing the existence of phase shift in nonlinear wave simulation. In this paper, the simulation of nonlinear waves in mixed Eulerian and Lagrangian framework using finite element method (FEM) is investigated by applying two different velocity calculation methods viz, cubic spline and least squares (LS). The simulated wave surface elevation has been compared with the experimental measurements. The coherence analysis has been carried out using the wavelet transformation, which gives a better understanding between the numerical and the experimental results with respect to the time–frequency space, compared with the conventional Fourier transformation. It is observed that the application of cubic spline approach leads to a higher phase difference for steeper waves. The present study has shown that the phase difference exists at the higher modes rather than at the primary period. For waves with steepness (wave height/wave length) higher than 0.04, LS approach is found to be effective in capturing the higher‐order frequency components in the event of nonlinearity. In addition, the comparison of numerical simulations with that from PIV measurements for the tests with solitary waves is also reported. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献