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41.
Hepatocellular carcinoma (HCC) is the most dominant primary liver cancer, which can be caused by chronic hepatitis virus infections and other environmental factors. Resection, liver transplantation, and local ablation are only a few of the highly effective and curative procedures presently accessible. However, other complementary treatments can reduce cancer treatment side effects. In this present work, we evaluated the activity of Moroccan scorpion venom Buthus occitanus and its fractions obtained by chromatography gel filtration against HCC cells using a 3D cell culture model. The venom was fractionated by gel filtration chromatography, each fraction and the crude venom was tested on normal hepatocytes (Fa2N-4 cells). Additionally, the fractions and the crude venom were tested on MCTSs (multicellular tumor spheroids), and this latter was generated by cultivate Huh7.5 cancer cell line with WI38 cells, LX2 cells, and human endothelial cells (HUVEC). Our results indicate that Buthus occitanus venom toxin has no cytotoxic effects on normal hepatocytes. Moreover, it is reported that F3 fraction could significantly inhibit the MCTS cells. Other Protein Separation Techniques (High-performance liquid chromatography) are needed in order to identify the most active molecule.  相似文献   
42.
A sensitive and specific luminescence method for the determination of Fexofenadine (FEX), in pharmaceutical formulations is reported. The method is based on the sensitization of terbium (Tb3+) by complex formation with FEX. The luminescence signal for Tb–FEX complex is greatly enhanced by the addition of triethylamine (ET3N) and zinc nitrate in methanol solution. Monitoring of the signal is accomplished when the instrument is in the phosphorescence mode with the excitation and emission wavelengths set at λex = 220 nm and λem = 550 nm respectively. Optimum conditions for the formation of the complex in methanol were 2.25 × 10?6 M of Tb3+, 5.00 × 10?6 M of Et3N and Zn2+ which allows for the determination of 10–800 ppb of FEX in the batch mode with a detection limit of 0.3 ppb. The proposed method was successfully applied for the determination of FEX in pharmaceutical formulations.  相似文献   
43.
New and emerging demand for polyurethane (PU) continues to rise over the years. The harmful isocyanate binding agents and their integrated PU products are at the height of environmental concerns, in particular PU (macro and micro) pollution and their degradation problems. Non-isocyanate poly(hydroxy urethane)s (NIPUs) are sustainable and green alternatives to conventional PUs. Since the introduction of NIPU in 1957, the market value of NIPU and its hybridized materials has increased exponentially in 2019 and is expected to continue to rise in the coming years. The secondary hydroxyl groups of these NIPU′s urethane moiety have revolutionized them by allowing for adequate pre/post functionalization. This minireview highlights different strategies and advances in pre/post-functionalization used in biobased NIPU. We have performed a comprehensive evaluation of the development of new ideas in this field to achieve more efficient synthetic biobased hybridized NIPU processes through selective and kinetic understanding.  相似文献   
44.
Journal of Thermal Analysis and Calorimetry - Phase relationships in the Al–Re binary system have been thermodynamically reassessed by using the CALPHAD technique to take into account the...  相似文献   
45.
Kinetics and Catalysis - Our work is around the heterogeneous catalysts based on phosphate. This is all the more important as Morocco has a significant wealth of world reserves of this mineral....  相似文献   
46.
In this work, we shall consider a new class (Σr) of local submartingales of the form Xt = Mt + At, where (Mt)t ? 0 is a càdlàg (right continuous with left limits) local martingale, (At)t ? 0 is a càdlàg increasing process, and the measure (dA) is carried by the set {t: Xt ? = 0}.

The aim of the present paper is to study the positive and negative parts of processes of this class and establish some martingale characterizations. The formula of relative martingales is derived in terms of last passage time. Finally, by using balayage formula, we calculate predictable compensator.  相似文献   
47.
In this article, a mathematical model is analyzed to investigate the effects of Hall current and heat transfer on the flow of a fourth grade fluid between two heated and rotating disks. The corresponding problem of velocity and temperature are solved analytically by homotopy analysis method. Comparison is given between the results of velocity in fourth grade, third grade, second grade, and viscous fluids. The variation of pertinent parameters are graphed and discussed. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010  相似文献   
48.
Several chemical reactions were carried out on 3‐(benzothiazol‐2‐yl‐hydrazono)‐1,3‐dihydro‐indol‐2‐one ( 2 ). 3‐(Benzothiazol‐2‐yl‐hydrazono)‐1‐alkyl‐1,3‐dihydro‐indol‐2‐one 3a , 3b , 3c have been achieved. Reaction of compound 2 with ethyl bromoacetate in the presence of K2CO3 resulted the uncyclized product 4 . Reaction of compound 2 with benzoyl chloride afforded dibenzoyl derivative 5 . Compound 2 was smoothly acetylated by acetic anhydride in pyridine to give diacetyl derivative 6b . Moreover, when compound 4 reacted with methyl hydrazine, it yielded dihydrazide derivative 7 , whereas the hydrazinolysis of this compound with hydrazine hydrate gave the monohydrazide derivative 8 . {N‐(Benzothiazol‐2‐yl‐N′‐(3‐oxo‐3,4‐dihydro‐2H‐1,2,4‐triaza‐fluoren‐9‐ylidene)hydrazino]‐acetic acid ethyl ester ( 9 ) was prepared by ring closure of compound 8 by the action of glacial acetic acid. In addition, the reaction of 2‐hydrazinobenzothiazole ( 1 ) with d ‐glucose and d ‐arabinose in the presence of acetic acid yielded the hydrazones 10a , 10b , respectively. Acetylation of compound 10b gave compound 11b . On the other hand, compound 13 was obtained by the reaction of compound 1 with gama‐d ‐galactolactone ( 12 ). Acetylation of compound 13 with acetic anhydride in pyridin gave the corresponding N1‐acetyl‐N2‐(benzothiazolyl)‐2‐yl)‐2,3,4,5,6‐penta‐O‐acetyl‐d ‐galacto‐hydrazide ( 14 ). Better yields and shorter reaction times were achieved using ultrasound irradiation. The structural investigation of the new compounds is based on chemical and spectroscopic evidence. Some selected derivatives were studied for their antimicrobial and antiviral activities.  相似文献   
49.
The reaction of 1‐trimethylsilyl‐indazole with boranes affords indazaboles accompanied by elimination of trimethysilane. Thus, the two isomers of parent indazabole are formed in a 1:1 ratio using borane in THF (BH3/THF), characterized by NMR spectroscopy in solution (1H, 11B and 13C NMR). In contrast, the analogous reaction with 1,2‐bis(tetramethylene)diborane(6) proceeds to give a single isomer of the B‐alkylated indazabole via symmetric ring cleavage of the diborane(6), as shown by NMR in solution and X‐ray structural analysis in the solid state. The molecular structure is fluxional in solution. In the solid state, the central B2N4 ring adopts a distorted boat conformation. Calculated gas phase geometries of the parent indazaboles and of the B‐alkylated indazabole were optimized by DFT methods at the B3LYP/6‐311 + G(d,p) level of theory. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
50.
In this paper, we introduce the classes of (B, ρ)-type I and generalized (B, ρ)-type I, and derive various sufficient optimality conditions and mixed type duality results for multiobjective control problems under (B, ρ)-type I and generalized (B, ρ)-type I assumptions.  相似文献   
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