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21.
S.?BabootaEmail author S.?P.?Agarwal 《Journal of inclusion phenomena and macrocyclic chemistry》2005,51(3-4):219-224
Meloxicam is a non steroidal anti inflammatory drug, used in the treatment of rheumatoid and osteoarthiritis. It is practically insoluble in water and its prolonged use is associated with the incidence of side effects like gastro intestinal perforations, ulcerations and bleeding. Therefore, an attempt has been made to improve the aqueous solubility of the drug by making an inclusion complex using hydroxy propyl β cyclodextrin(HPβ-CD). The complexes were prepared by physical mixture and freeze drying method. The different methods employed for evaluation such as DSC, XRD, SEM and FT-IR studies indicated complete formation of the complex by freeze drying method in a molar ratio of 1:2. The prepared complexes showed improved in-vitro dissolution profile as compared to the pure drug. 相似文献
22.
Use of a novel coupling reagent, N,N-bis[2-oxo-3-oxazolidinyl]phosphorodiamidic chloride (BOPDC) in the synthesis of oligodeoxyribonucleotides is described. This reagent allows the synthesis of phosphotriesters in high yields (70–80%) without detectable side reactions. Synthesis of a hexanucleotide, d(A-A-C-C-C-G) is presented as an example. 相似文献
23.
The use of fenugreek mucilage, a natural polysaccharide and a direct food additive, as a flocculating agent for removal of suspended and dissolved solids from sewage effluent has been reported. A flocculation study has been done by the standard jar test method. The percent removal of suspended solid (SS) and dissolved solid (TDS) was determined by varying the polymer dose, pH and contact time. X-ray diffraction patterns of the solid waste material of mucilage and flocs (so obtained after treatment) were used to suggest the incorporation of the crystalline waste material in the mucilage. The optimal mucilage concentration was found to be 0.16 mg/l. The suitable pH range for maximum solid removal (SS and TDS) was alkaline and the time required for treatment was 1-3 h. 相似文献
24.
Vapor phase catalytic oxidation of toluene over perovskites viz., LaCoO3, LaCrO3 and LaFeO3 has been studied. The maximum activity was observed at 450°C. The oxidation is first order. The order of catalytic reactivity is LaCoO3>LaFeO3>LaCrO3. The activation energy (Ea) values for LaCoO3, LaFeO3 and LaCrO3 are 13.4, 23.93 and 25.31 kJ/mol, respectively. 相似文献
25.
Summary A study of the Cd(CN)2 +x X– [Cd(CN)2X
x
]
x–
equilibrium (where X = Cl, Br or CNS) has been carried out at 18° and 38° by measuring the solubility of cadmium cyanide in potassium chloride, bromide and thiocyanate at various concentrations, and at a high ionic strength (6 M) maintained with sodium perchlorate to minimise the effect of activity coefficients. Equilibrium constants forx = 1 and 2 have been calculated and clearly favour the situation wherex = 1. H values for the dissociation of [Cd(CN)2X]– have also been calculated. 相似文献
26.
Study of EPR, optical properties and electrical conductivity of vanadyl doped Bi2O3.PbO.B2O3 glasses
Gahlot PS Agarwal A Seth VP Sanghi S Gupta SK Arora M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(6):1189-1194
Heavy metal based oxide glasses having composition xBi(2)O(3).(0.30 - x)PbO.0.70B(2)O(3) have been prepared (0.00 < or = x < or = 0.15, mol%) containing 2.0mol% of V(2)O(5) by normal melt-quenching technique. Electron paramagnetic resonance (EPR), optical spectra and dc conductivity of these glasses have been studied. Spin Hamiltonian parameters (SHP) of VO(2+) ions, dipolar hyperfine parameter, P and Fermi contact interaction parameter, K, molecular orbital coefficients (alpha(2) and gamma(2)) and optical band gap have been calculated. It is observed that in these glasses, the tetragonal nature of V(4+)O(6) complex increases with Bi(2)O(3) content. Increase in Bi(2)O(3):PbO ratio results in the contraction of 3d(xy) orbit of the unpaired electron in the vanadium ion, and the SHP are dependent on the theoretical optical basicity, Lambda(th). In present glasses, the conductivity (activation energy) first decreases (increases) with increase in mol% of Bi(2)O(3) content upto x = 0.08 and then shows a maxima (minima) at x = 0.10 and then starts decreasing (increasing) upto x < or = 0.15 with mol% of Bi(2)O(3) content. 相似文献
27.
A new series of complexes of 5,6-benzoquinoline (Benzqn) with lanthanide perchlorates with the general composition Ln(ClO4)3·7Benzqn (Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy or Ho) were synthesised and characterised by elemental analysis, conductance, molecular weight and infrared spectra. The thermal behaviour of these complexes have also been studied. 相似文献
28.
29.
Ravinder Agarwal V. R. Singh M. M. Pradhan Ved Singh 《International Journal of Infrared and Millimeter Waves》1991,12(2):115-123
The occurance of the urinary stones varies according to the geographical regions. The presence of stones in the urinary system causes pain and discomfort. These generate colics and hence are sometimes life threatening. In the present study, infrared measurements have been made on several stone samples. It has been found that calcium oxalate, calcium phosphate, magnesiunm ammonium phosphate, calcium carbonate, uric acid, -cystine and xanthin are present, as expected. Also, silicon dioxide is found to be present in some of the stones but in small quantity, in addition to the above constituents. This constituent is responsible to exhibit piezoelectricity in the urinary calculi. 相似文献
30.
Paul Grocki Mark Woollam Luqi Wang Shengzhi Liu Maitri Kalra Amanda P. Siegel Bai-Yan Li Hiroki Yokota Mangilal Agarwal 《Molecules (Basel, Switzerland)》2022,27(13)
Volatile organic compounds (VOCs) in urine are potential biomarkers of breast cancer. Previously, our group has investigated breast cancer through analysis of VOCs in mouse urine and identified a panel of VOCs with the ability to monitor tumor progression. However, an unanswered question is whether VOCs can be exploited similarly to monitor the efficacy of antitumor treatments over time. Herein, subsets of tumor-bearing mice were treated with pitavastatin at high (8 mg/kg) and low (4 mg/kg) concentrations, and urine was analyzed through solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Previous investigations using X-ray and micro-CT analysis indicated pitavastatin administered at 8 mg/kg had a protective effect against mammary tumors, whereas 4 mg/kg treatments did not inhibit tumor-induced damage. VOCs from mice treated with pitavastatin were compared to the previously analyzed healthy controls and tumor-bearing mice using chemometric analyses, which revealed that mice treated with pitavastatin at high concentrations were significantly different than tumor-bearing untreated mice in the direction of healthy controls. Mice treated with low concentrations demonstrated significant differences relative to healthy controls and were reflective of tumor-bearing untreated mice. These results show that urinary VOCs can accurately and noninvasively predict the efficacy of pitavastatin treatments over time. 相似文献