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741.
742.
Farhad Ullah Abida Raza Ismail Khan Fahim Ullah Khan Muhammad Hassan 《液相色谱法及相关技术杂志》2017,40(20):1020-1030
Methotrexate (MTX) is an anticancer drug while metoclopramide (MCP) is an antiemetic agent. Both the drugs are commonly coprescribed to avoid the emesis caused by anticancer drug. In this study, a novel, rapid, sensitive, and cost-effective reverse-phase high-performance liquid chromatography method was developed and validated for simultaneous determination of the methotrexate and metoclopramide in biological and pharmaceutical samples using sparfloxacin as internal standard. The analytes were separated on a Kromasil 100-5C18 RP (250?×?4.6?mm, 5?µm) column, methanol, and 0.05% trifloroacetic acid (36:64?v/v) as mobile phase with a flow rate of 1?mL/min, detection wavelength of 290?nm, and column oven temperature at 40°C. Both the analytes were extracted from physiological fluids (bovine aqueous humor, vitreous humor, and human plasma) using mixture of methanol and 10% perchloric acid (50:50 v/v). The method was linear over the concentration range of 0.025–1.0?µg/mL for methotrexate and 0.030–1.0?µg/mL for metoclopramide. The % recovery from human plasma was 98.57 and 96.74% for MTX and MCP, respectively, while from aqueous humor and vitreous humor was 95.84 and 98.51% for MTX.The developed method was applied for in vitro release of MTX from polymeric nanoparticles and can be applied for analysis of pharmaceutical and biological samples containing both the drugs. 相似文献
743.
Abdul Qadir Nausheen Khan Muhammad Arif Musarrat Husain Warsi Shehla Nasar Mir Najib Ullah Mohammad Yusuf 《印度化学会志》2022,99(6):100503
Trigonella foenumgraecum L. (TF) is a medicinal herb, belonging to the family Legumes. It has shown positive results in remedying hypo-cholesterolemic, anti-inflammatory, antibacterial, antioxidant, anti-lipidemia, antilithigenic, hepatoprotective, antiulcer, anticarcinogenic, antifungal and other miscellaneous pharmacological effects of fenugreek. The n-hexane extract of Trigonella foenumgraecum L. Seeds (TF) was analysed by gas chromatography-mass spectroscopy for identification and characterization of its therapeutic claim by traditional system. DPPH method was used to determine the antioxidant activity of Trigonella foenumgraecum L-seeds extract using UV spectrophotometer at a wavelength of 518 nm as it is one of the most sorted methods for antioxidant activity. The major compounds discovered in Trigonella foenumgraecum L. seeds extract are Linoleic acid (48.01%); 9,12-Octadecadienoic acid (Z,Z)-, 2,3-dihydroxypropyl ester (24.65%); 2-[4-Methyl-6-(2,6,6-trimethylcyclohex-1-enyl)hexa-1,3,5-trienyl]cyclohex-1-en-carboxaldehyde(1.88%); Nonane dioic acid, bis (2-ethylhexyl) ester (1.09%); Bis (2-ethylhexyl) ester of azelaic acid (11.97%); Elemicin (0.51%); cis-Linoleic acid methyl ester (0.76%); Linoleic acid chloride(0.57%); Ethyl oleate(0.18%); Isopropyl linoleate (0.38%); Dihydrovallesiachotamine (0.06%); 4-(2,2-Dimethyl-6-methylenecyclohexyl) butanal(0.12%); Citronellyl myristate (0.09%); Rhaphidecursinol B(0.25%); 5-Methoxygalbelgin (0.07%); Vitamin E (0.31%); 1,1,1,5,5,5-hexafluoro-4-{[3-(trifluoromethyl) phenyl]imino}-2-pentanone (0.76%); γ-Sitosterol (0.66%); 1-(1,5-Dimethylhexyl)-3a,12a-dimethyltetradecahydro-1H-cyclopenta[a]cyclopropa[e]phenanthren-7-ol (0.16%) and (9Z)-9-Octadecenyl (9Z)-9-hexadecenoate (1.57%). The results showed potential antioxidant activity of n-hexane extract of Trigonella foenumgraecum L. seeds by showing significant reduction in free radical against DPPH. The hexane extract of Trigonella foenumgraecum L. seeds comprises various non-water-soluble (nonpolar) constituents. These compounds were established qualitatively via GC-MS evaluation. The free radical scavenging activity of the plant extract was established owning to the presence of compounds such as terpenes, vitamin E, and unsaturated fatty acids. 相似文献
744.
Hala A. Hejazi M. Ijaz Khan Ali Raza Kamel Smida Sami Ullah Khan Iskander Tlili 《印度化学会志》2022,99(7):100564
The interest of researchers towards the nanofluids is noticed in recent years due to leading applications in thermal systems and industrial framework. Referring to such motivations, current study explores the role of velocity slip effects for the mixed convection flow of nanofluid endorsed due to inclined surface. The Casson base fluid model for which the thermal impact needs to be improved. The analysis is observed when the role of velocity slip is important. The modeling of unsteady free convective flow problem yields partial differential system. The Atangana-Baleanu (AB) and Caputo-Fabrizio (CF) fractional operators are implemented in order to simulates the computation of problem. The graphical presentations are prepared in order to check the physical dynamic of parameters. 相似文献
745.
Durre Shahwar Naeem Ahmad Asma Yasmeen Muhammad Akmal Khan Sami Ullah Rahman Atta-ur 《Natural product research》2015,29(3):274-276
Whole plant extracts of Croton sparsiflorus in methanol have shown significant enzyme inhibition and antioxidant activities. Bioassay-guided isolation of chloroform fraction at pH 3 resulted in the identification of crotsparinine (1) and crotsparine (2), while sparsiflorine (3) was purified from the chloroform fraction at pH 9. The structures of the compounds were confirmed through spectral analyses (EI-MS, 1H and 13C NMR). The isolated compounds 1–3 exhibited remarkable enzyme inhibition activity with IC50 values 27.01 ± 1.1, 22.26 ± 1.0 and 18.02 ± 1.3 μM in xanthine oxidase and 48.42 ± 1.5, 48.05 ± 1.4 and 7.42 ± 1.0 μM in acetylcholine esterase assays, respectively. These compounds also showed potent radical scavenging and reducing properties in DPPH and FRAP assays, respectively. The present results suggest the validity of the traditional uses of C. sparsiflorus in rheumatism and gout. Furthermore, the isolated noraporphine alkaloids can be useful in the treatment of neurodegenerative diseases. 相似文献
746.
Ehsan Mehdad Jack P C Kleijnen 《The Journal of the Operational Research Society》2015,66(11):1804-1814
Kriging is a popular method for estimating the global optimum of a simulated system. Kriging approximates the input/output function of the simulation model. Kriging also estimates the variances of the predictions of outputs for input combinations not yet simulated. These predictions and their variances are used by ‘efficient global optimization’ (EGO), to balance local and global search. This article focuses on two related questions: (1) How to select the next combination to be simulated when searching for the global optimum? (2) How to derive confidence intervals for outputs of input combinations not yet simulated? Classic Kriging simply plugs the estimated Kriging parameters into the formula for the predictor variance, so theoretically this variance is biased. This article concludes that practitioners may ignore this bias, because classic Kriging gives acceptable confidence intervals and estimates of the optimal input combination. This conclusion is based on bootstrapping and conditional simulation. 相似文献
747.
In addition to inequality constraints, many mathematical models require equality constraints to represent the practical problems appropriately. The existence of equality constraints reduces the size of the feasible space significantly, which makes it difficult to locate feasible and optimal solutions. This paper presents a new equality constraint handling technique which enhances the performance of an agent-based evolutionary algorithm in solving constrained optimization problems with equality constraints. The technique is basically used as an agent learning process in the agent-based evolutionary algorithm. The performance of the proposed algorithm is tested on a set of well-known benchmark problems including seven new problems. The experimental results confirm the improved performance of the proposed technique. 相似文献
748.
Inspired by the insightful article [4], we revisit the Nualart–Peccati criterion [13] (now known as the Fourth Moment Theorem) from the point of view of spectral theory of general Markov diffusion generators. We are not only able to drastically simplify all of its previous proofs, but also to provide new settings of diffusive generators (Laguerre, Jacobi) where such a criterion holds. Convergence towards Gamma and Beta distributions under moment conditions is also discussed. 相似文献
749.
Ehsan Zolfonoun Abolfazl Semnani 《International journal of environmental analytical chemistry》2013,93(5):327-336
A simple and fast method for preconcentration and determination of ultra trace amounts of lead(II), mercury(II) and cadmium(II) in water samples is presented. Lead, mercury and cadmium adsorbed quantitatively during passage of water samples (pH?=?7, flow rate?=?20 mL min?1) through octadecyl silica membrane disks modified with 5,5′-dithiobis(2-nitrobenzoic acid). The retained lead, mercury and cadmium are then stripped from the disk with a minimal amount of 1 M hydrochloric acid solution as eluent, and determined by atomic absorption spectrometry. The influence of flow rates of the eluent and sample solution, the amount of ligand, type and least amount of eluent, pH of sample, effect of other ions and breakthrough volume are determined. The breakthrough volume of the method is greater than 2000 mL for lead and greater than 1500 mL for mercury and cadmium, which results in an enrichment factor of 200 for lead and an enrichment factor of 150 for both mercury and cadmium. The limit of detection of the proposed method is 177, 2 and 13 ng l?1 for lead, mercury and cadmium, respectively. 相似文献
750.
Ehsan Zolfonoun Maryam Salahinejad 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(3):1801-1807
A new simple and rapid vortex-assisted liquid–liquid microextraction method was applied for the determination of thorium in water samples. In this method, chloroform used as extraction solvent was directly injected into the water sample solution. The extraction solvent was dispersed into the aqueous phase under vigorously shaking with the vortex. After centrifuging, the fine droplets of extractant phase were settled to the bottom of the conical-bottom centrifuge tube. The effect of different experimental parameters on the performance of the method were studied and discussed. Under the optimum conditions, the detection limit for Th(IV) was 7.5 ng mL?1. The precision of the method, evaluated as the relative standard deviation obtained by analyzing of 10 replicates, was 2.8 %. The practical applicability of the developed method was examined using natural water and monazite sand samples. 相似文献