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61.
Rabail Ujan Pervaiz Ali Channar Aamer Saeed Qamar Abbas Hummera Rafique Saba Ashraf Mahboob Ali Rind Abbas Hassan Anwar Ul-Hamid Mubashar Hassan Hussain Raza Sung-Yum Seo 《Journal of heterocyclic chemistry》2021,58(10):1929-1935
The porcine pancreatic elastase inhibition and free-radical scavenging play a crucial role in age progression. All the series of 10 newly synthesized benzimidazole thioureas ( 4a-j ) were assessed for elastase inhibition and radical scavenging activity to identify the suitable anti-aging ingredient for cosmetics products. The compounds 4e , 4f , 4g , and 4h showed inhibition better than the standard, while compound 4f showed the most significant elastase inhibition with the IC50 value of 1.318 ± 0.025 μM compared with oleanic acid IC50 13.451 ± 0.014 used ±1.989 and 41.563 ± 0.824, respectively, as standard. Molecular docking studies were performed and the compound 4f showed binding energy of 7.2 kcal/mol. Kinetics studies revealed inhibition of the pancreatic elastase in a competitive manner. The relative binding energy and structure activity relationship (SAR) identified compound 4f as an effective inhibitor of porcine pancreatic elastase. Compounds 4e and 4i showed remarkable free-radical scavenging activity with SC50 values of 26.421. 相似文献
62.
Singh Mhaveer Kamal Yunus T.-K. Tamboli Ennus T. Parveen Rabea Ansari Shahid H. Ahmad Sayeed 《平面色谱法杂志一现代薄层色谱法》2013,26(3):267-273
JPC – Journal of Planar Chromatography – Modern TLC - A novel HPTLC method has been developed for the estimation of glabridin in Licorice rhizome and its Unani polyherbal formulation... 相似文献
63.
64.
Shahid Muhammad Kim Kwangsoo Kim Guinyun Naik Haladhara Zaman Muhammad Lee Young-Ouk Cho Young-Sik 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(3):1971-1981
Journal of Radioanalytical and Nuclear Chemistry - We measured excitation functions for the production of the 108m,108g,109g,110m,110g,111gIn, the 109g,111mCd, and the 105g,106m,110m,111gAg in... 相似文献
65.
S. Drozdov M. Rafique S. Skali-Lami 《Theoretical and Computational Fluid Dynamics》2004,18(2-4):137-150
An incompressible liquid flow in the gap between two coaxial cylinders, such that the inner rotating (wavy) cylinder has a periodically varying radius along the axial direction while the outer stationary cylinder has a constant radius, is studied experimentally and theoretically. Basic attention is focused on the symmetry-breaking phenomenon of the vortex flow arising from the rotation of the inner wavy cylinder. It is found that the symmetry-breaking phenomenon of the vortical flow structures in this geometry is accompanied by the occurrence of a self-induced axial pressure gradient. A theoretical formulation of the problem of periodic vortical flow prevailing in such a geometry having large axial length is presented. The comparison between the computed and the experimental results is presented and the underlying phenomena are discussed. 相似文献
66.
Castillo-Martínez E Bieringer M Shafi SP Cranswick LM Alario-Franco MÁ 《Journal of the American Chemical Society》2011,133(22):8552-8563
A novel ScVO(3) perovskite phase has been synthesized at 8 GPa and 1073 K from the cation-disordered bixbyite-type ScVO(3). The new perovskite has orthorhombic symmetry at room temperature, space group Pnma, and lattice parameters a = 5.4006(2) ?, b = 7.5011(2) ?, and c = 5.0706(1) ? with Sc(3+) and V(3+) ions fully ordered on the A and B sites of the perovskite cell. The vanadium oxygen octahedra [V-O(6)] display cooperative Jahn-Teller (JT) type distortions, with predominance of the tetragonal Q(3) over the orthorhombic Q(2) JT modes. The orthorhombic perovskite shows Arrhenius-type electrical conductivity and undergoes a transition to triclinic symmetry space group P-1 close to 90 K. Below 60 K, the magnetic moments of the 4 nonequivalent vanadium ions undergo magnetic long-range ordering, resulting in a magnetic superstructure of the perovskite cell with propagation vector (0.5, 0, 0.5). The magnetic moments are confined to the xz plane and establish a close to zigzag antiferromagnetic mode. 相似文献
67.
Shahid Hussain Arshad Muhammad Nawaz Naeem Nazra Sultana Zafar Iqbal Abdul Ghafar Shah 《Archive of Applied Mechanics (Ingenieur Archiv)》2011,81(8):999-1016
In the present work, vibration characteristics of thin functionally graded cylindrical shells are studied under the influence
of various boundary conditions. Fabrication of FGM cylindrical shell is carried out by using exponential volume fraction law.
Strain- and curvature-displacements relationships are taken from Love’s thin shell theory. The frequency equation in the form
of eigenvalue problem is obtained by adapting the Rayleigh-Ritz method. Characteristic beam functions are assumed to approximate
the axial modal dependence. Effects of exponential volume fraction law on the natural frequencies of the FGM cylindrical shells
for various boundary conditions are studied against circumferential wave number, length to radius ratio and thickness to radius
ratio for different values of power law exponents. Results evaluated show good agreement with those available in the literature. 相似文献
68.
Rafiq Shahid Abbas Zaheer Nawaz Muhammad Alharbi Sayer Obaid 《Journal of Thermal Analysis and Calorimetry》2021,145(6):3269-3279
Journal of Thermal Analysis and Calorimetry - A numerical model is developed to study the effects of temperature-dependent viscosity on heat transfer in magnetohydrodynamic flow of micropolar fluid... 相似文献
69.
Muhammad Zaman Muhammad Hammad Butt Waqar Siddique Muhammad Omer Iqbal Naveed Nisar Asma Mumtaz Hafiza Yusra Nazeer Abdulrahman Alshammari Muhammad Shahid Riaz 《Molecules (Basel, Switzerland)》2022,27(23)
Tenofovir alafenamide (TAF) is an antiretroviral (ARV) drug that is used for the management and prevention of human immunodeficiency virus (HIV). The clinical availability of ARV delivery systems that provide long-lasting protection against HIV transmission is lacking. There is a dire need to formulate nanocarrier systems that can help in revolutionizing the way to fight against HIV/AIDS. Here, we aimed to synthesize a polymer using chitosan and polyethylene glycol (PEG) by the PEGylation of chitosan at the hydroxyl group. After successful modification and confirmation by FTIR, XRD, and SEM, TAF-loaded PEGylated chitosan nanoparticles were prepared and analyzed for their particle size, zeta potential, morphology, crystallinity, chemical interactions, entrapment efficacy, drug loading, in vitro drug release, and release kinetic modeling. The fabricated nanoparticles were found to be in a nanosized range (219.6 nm), with ~90% entrapment efficacy, ~14% drug loading, and a spherical uniform distribution. The FTIR analysis confirmed the successful synthesis of PEGylated chitosan and nanoparticles. The in vitro analysis showed ~60% of the drug was released from the PEGylated polymeric reservoir system within 48 h at pH 7.4. The drug release kinetics were depicted by the Korsmeyer–Peppas release model with thermodynamically nonspontaneous drug release. Conclusively, PEGylated chitosan has the potential to deliver TAF from a nanocarrier system, and in the future, cytotoxicity and in vivo studies can be performed to further authenticate the synthesized polymer. 相似文献
70.
Shoaib Khan Shahid Iqbal Mazloom Shah Wajid Rehman Rafaqat Hussain Liaqat Rasheed Hamad Alrbyawi Ayed A. Dera Mohammed Issa Alahmdi Rami Adel Pashameah Eman Alzahrani Abd-ElAziem Farouk 《Molecules (Basel, Switzerland)》2022,27(20)
A unique series of sulphonamide derivatives was attempted to be synthesized in this study using a new and effective method. All of the synthesized compounds were verified using several spectroscopic methods, including FTIR, 1H-NMR, 13C-NMR, and HREI-MS, and their binding interactions were studied using molecular docking. The enzymes urease and α-glucosidase were evaluated against each derivative (1–15). When compared to their respective standard drug such as acarbose and thiourea, almost all compounds were shown to have excellent activity. Among the screened series, analogs 5 (IC50 = 3.20 ± 0.40 and 2.10 ± 0.10 µM) and 6 (IC50 = 2.50 ± 0.40 and 5.30 ± 0.20 µM), emerged as potent molecules when compared to the standard drugs acarbose (IC50 = 8.24 ± 0.08 µM) and urease (IC50 = 7.80 ± 0.30). Moreover, an anti-microbial study also demonstrated that analogs 5 and 6 were found with minimum inhibitory concentrations (MICs) in the presence of standard drugs streptomycin and terinafine. 相似文献