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排序方式: 共有321条查询结果,搜索用时 31 毫秒
71.
Dibyalochan Mohanty Ameeduzzafar Zafar Mohammed Jafar Atul Kumar Upadhyay Mohammad Akiful Haque Jeetendra Kumar Gupta Vasudha Bakshi Mohammed M. Ghoneim Sultan Alshehri Mohammed Asadullah Jahangir Mohammed Javed Ansari 《Molecules (Basel, Switzerland)》2022,27(9)
Objective: The present study aimed to develop and optimize esomeprazole loaded proniosomes (EZL-PNs) to improve bioavailability and therapeutic efficacy. Method: EZL-PNs formulation was developed by slurry method and optimized by 33 box-Bhekhen statistical design software. Span 60 (surfactant), cholesterol, EZL concentration were taken as independent variables and their effects were evaluated on vesicle size (nm), entrapment efficiency (%, EE) and drug release (%, DR). Furthermore, optimized EZL-PNs (EZL-PNs-opt) formulation was evaluated for ex vivo permeation, pharmacokinetic and ulcer protection activity. Result: The EZL-PNs-opt formulation showed 616 ± 13.21 nm of vesicle size, and 81.21 ± 2.35% of EE. EZL-PNs-opt exhibited negative zeta potential and spherical confirmed scanning electron microscopy. EZL-PNs-opt showed sustained release of EZL (95.07 ± 2.10% in 12 h) than pure EZL dispersion. The ex-vivo gut permeation result exhibited a significantly (p < 0.05) enhanced flux than pure EZL. The in vivo results revealed 4.02-fold enhancement in bioavailability and 61.65% protection in ulcer than pure EZL dispersion (43.82%). Conclusion: Our findings revealed that EZL-PNs formulation could be an alternative delivery system of EZL to enhance oral bioavailability and antiulcer activity. 相似文献
72.
Waqas M. Akram Nimra Asghar Z. Gulzar M. M. Javed M. A. 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2069-2074
Journal of Thermal Analysis and Calorimetry - Heat transportation analysis subjected to porous medium consideration has increased because of industrial and engineering utilization. Typical examples... 相似文献
73.
Dr. Farah Benyettou Dr. Anjana Ramdas Nair Yaereen Dho Dr. Thirumurugan Prakasam Dr. Renu Pasricha Jamie Whelan Prof. Hassan Traboulsi Javed Mazher Prof. Kirsten C. Sadler Prof. Ali Trabolsi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(23):5270-5279
Triphenylphosphine (TPP) surface-functionalized and F-108 Pluronic-stabilized gold nanoparticles (F-108@TPP-AuNPs) have been synthesized through a one-step approach, leading to well-defined (9.6±1.6 nm) and water-soluble nanoparticles by microwave heating an aqueous solution of TPP-AuICl in the presence of a Pluronic polymer under basic conditions. TPP release was negligible under physiological conditions, but enhanced significantly at an acidic pH (5.4) mimicking that of a cancer cell. Laser irradiation (532 nm) raised the temperature of an aqueous solution of F-108@TPP-AuNPs to 51.7 °C within 5 min, confirming efficient light-to-heat conversion capabilities without significant photodegradation. TEM confirmed intracellular localization of F-108@TPP-AuNPs in the cytosol, endosomes and lysosomes of HeLa cells. F-108@TPP-AuNPs were well tolerated by HeLa cells and zebrafish embryos at ambient temperatures and became toxic upon heat activation, suggesting synergistic interactions between heat and cytotoxic action by TPP. 相似文献
74.
N Selvakumar B.Yadi ReddyA.Malar Azhagan Manoj Kumar KheraJ.Moses Babu Javed Iqbal 《Tetrahedron letters》2003,44(37):7065-7069
A short and efficient route to 1-methoxyindoles via a novel rearrangement is disclosed. This route involves only three steps from commercially available nitro compounds. The methodology is also generalized with a variety of examples to afford a series of 2-substituted-1-methoxyindoles possessing an electron-withdrawing group at position 3. In addition, a 1-methoxyindole compound 10 was converted to the corresponding indole 11 under mild conditions thereby constituting a new synthesis of substituted indoles. 相似文献
75.
N. Selvakumar Manoj Kumar KheraB.Yadi Reddy D. SrinivasA.Malar Azhagan Javed Iqbal 《Tetrahedron letters》2003,44(37):7071-7074
A direct synthesis of naturally occurring 9-methoxycarbazole-3-carbaldehyde 1, based on our methodology for the synthesis of 1-methoxyindoles, is reported. A novel benzannulation strategy was employed using ring closing metathesis as the key step in this total synthesis. The synthesis of the natural product 1 has been achieved in seven steps in 14% overall yield from commercial materials and in only four steps from a methoxyindole compound obtained using the new methodology. 相似文献
76.
Muhammad Javed Iqbal Qaisar Mahmood Malik 《The Journal of chemical thermodynamics》2005,37(12):1347-1350
The apparent molar volume of paracetamol (4-acetamidophenol) in water, 0.1 M HCl and 0.154 M NaCl as solvents at (298.15, 303.15, 308.15 and 310.65) K temperatures and at a pressure of 101.325 kPa were determined from the density data obtained with the help of a vibrating-tube Anton Paar DMA-48 densimeter. The partial molar volume, Vm, of paracetamol in these solvents at different temperatures was evaluated by extrapolating the apparent molar volume versus molality plots to m = 0. In addition, the partial molar expansivity, E°, the isobaric coefficient of thermal expansion, αp, and the interaction coefficient, Sv, have also been computed. The expansivity data show dependence of E° values on the structure of the solute molecules. 相似文献
77.
[Reaction: see text]. Small peptides having a 3-bromobenzyl group at the C-termini and n-alkynoyl group at the N-termini undergo a smooth copper-free intramolecular Sonogashira coupling reaction to afford the corresponding cyclic peptides in moderate yields. Scope and limitations of this macrocyclization is demonstrated with di-, tri-, and tetrapeptides. 相似文献
78.
M. Afzal Javed Hanif Imtiaz Hanif Riaz Qadeer M. Saleem 《Journal of Radioanalytical and Nuclear Chemistry》1990,139(2):203-214
The samples were introduced into the XRF spectrometer in ordinary flat bottom polyethylene bottles for the estimation of Zr or Hf in presence of one another in solution. By using high voltage (50 kV) and high current (50 mA) least limits of detection obtained were an order of magnitude better than other conventional analytical techniques. Relations of intensity to concentration in various concentration ranges have been determined and the results are compared with those of other analytical techniques. 相似文献
79.
D. Srinivasa Reddy Trideep V. Rajale K. Shivakumar Javed Iqbal 《Tetrahedron letters》2005,46(6):979-982
A mild and efficient one-pot method for the synthesis of vinylogous carbamates is reported starting from alkyl azides under a hydrogen atmosphere using 10% Pd/C. The resulting products are useful intermediates for the synthesis of heterocyclic compounds, natural products, and in peptidomimetics. 相似文献
80.
A novel approach towards the synthesis of the C1-C10 fragment of the biologically active antimitotic agent rhizoxin D is described. The synthesis involves a stereoselective Michael addition reaction of lithium diallyl cuprate with an α,β-unsaturated six membered lactone. 相似文献