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121.
The androgen receptor (AR) is a pivotal target for the treatment of prostate cancer (PC) even when the disease progresses toward androgen-independent or castration-resistant forms. In this study, a series of 15 bicalutamide analogues (sulfide, deshydroxy, sulfone, and O-acetylated) were prepared and their antiproliferative activity evaluated against four different human prostate cancer cell lines (22Rv1, DU-145, LNCaP, and VCap). Bicalutamide and enzalutamide were used as positive controls. Seven of these compounds displayed remarkable enhancement in anticancer activity across the four PC cell lines. The deshydroxy analogue (16) was the most active compound with IC50 = 6.59–10.86 µM. Molecular modeling offers a plausible explanation of the higher activity of the sulfide analogues compared to their sulfone counterparts.  相似文献   
122.
Journal of Fluorescence - Development of an efficient, portable and simple nanosensor-based systems with reliable analytical performance for on-site monitoring of vitamin B12 (VB12) are still major...  相似文献   
123.
The Ugi reaction goes fast with high yields in a recyclable and biodegradable low-melting mixture of choline chloride and urea (DES) as a novel and efficient reaction medium. The DES is applicable to a wide range of aldehydes, amines, isocyanides, and acids in good to excellent isolated yields (60–92%) and short reaction times (2–5 h) and can be reused four times without any loss of activity.  相似文献   
124.
Lactobacillus bulgaricus is a LAB strain which is capable of producing bacteriocin substances to inhibit Staphylococcus aureus. The aim of this study was to purify a bacteriocin-like inhibitory substance (BLIS) produced by L. bulgaricus FTDC 1211 using an aqueous impregnated resins system consisting of polyethylene-glycol (PEG) impregnated on Amberlite XAD4. Important parameters influencing on purification of BLIS, such as the molecular weight and concentration of PEG, the concentration and pH of sodium citrate and the concentration of sodium chloride, were optimized using a response surface methodology. Under optimum conditions of 11% (w/w) of PEG 4000 impregnated Amberlite XAD4 resins and 2% (w/w) of sodium citrate at pH 6, the maximum purification factor (3.26) and recovery yield (82.69% ± 0.06) were obtained. These results demonstrate that AIRS could be used as an alternate purification system in the primary recovery step.  相似文献   
125.

Since N-cadherin protein plays a remarkable role in cancer metastasis and tumor growth and progression, finding new effective inhibitors of this protein can be of high importance in cancer treatment. Nevertheless, few molecules have been introduced to inhibit N-cadherin protein to date. In this work, in order to find and present potent inhibitors, 3358 FDA-approved small molecules were docked against N-cadherin protein. All complexes with binding energy ??9 to ??8 kcal/mol were selected for protein-ligand interaction analysis. In the following, Tanimoto coefficient (Tc) was calculated for those molecules that established appropriate interactions with N-cadherin in order to compute the similarity score between them. Afterwards, molecular dynamics simulation and free energy calculations were done to estimate the stability and ability of the chosen ligands in complex with the target protein. Finally, seven small molecules among 3358 FDA-approved were suggested as potential inhibitors of N-cadherin protein.

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126.
The solubility data of acetaminophen in binary mixtures of 1-hexyl-4-methylpyridinium bromide and water were obtained over the temperature range from 293.15 to 313.15 K by using the gravimetric method under atmospheric pressure. Using the experimentally measured solubility values, the thermodynamic properties of dissolution, mixing and transfer processes were evaluated. The measured solubilities were correlated by the modified Wilson and the electrolyte non-random two liquid (E-NRTL) models.  相似文献   
127.
The simultaneous gravimetric and dilatometric techniques have been used to study the kinetics of aqueous free radical crosslinking copolymerization of acrylamide (AAm) and N,N'-methylenebisacrylamide (MBA) at different crosslinker ratios, and reaction temperatures. In this study, the gel properties were investigated using swelling measurements and microscopic techniques. Based on the data, it was proposed that the deviation point of the results of dilatometric technique from those of the gravimetric one can be a new criterion for gel point. The monomer conversion and the equilibrium swelling ratio of the hydrogels were measured as a function of the reaction time. Experimental data showed an inverse dependence of the critical gel point on crosslinker concentration. As the MBA/AAm ratio was decreased to 0.1?wt%, the product appearance changed. In addition, the effects of temperature on the reaction rate and critical gel point were studied. At higher temperatures, the equilibrium swelling ratio reached to its minimum value earlier. Besides, the hydrogel surface became smoother.  相似文献   
128.
Superabsorbent hydrogels based on the natural polymer chitosan and acrylic acid (CS/AAc) was prepared using 60Co gamma radiation as a source of initiation and crosslinking. The factors, which affect the preparation of CS/AAc hydrogels such as irradiation dose, CS/AAc ratios, and acrylic acid monomer concentrations, to get the best optimum conditions, were investigated. The kinetic studies of the swelling of CS/AAc hydrogel showed that it follows a Fickian type of water diffusion. The Fickian constant value ‘n’ was more than 0.5 with a high swelling capacity of 300 g/g as superabsorbent hydrogel. In addition, the suitability of CS/AAc hydrogel as carrier material for the drug Chlortetracycline-HCl has been investigated by adsorption isotherm studies. The performance of drug release from hydrogel systems, influenced by acrylic acid ratio and the effect of pH of the medium was studied.  相似文献   
129.
Journal of Analytical Chemistry - In the present study, a simple and efficient directly suspended-solidified floating organic droplet microextraction using deep eutectic solvent in combination with...  相似文献   
130.
Chlorine gas inhalation, similar to other toxic gas exposures, can impart a variety of effects to the entire airway ranging from mucous membrane irritation to acute respiratory distress syndrome. The extent and location of damage is determined by numerous situational factors such as the duration of exposure, quantity of gas released, environmental factors, and instituted chemical defense measures. Reactive airways dysfunction and nonspecific bronchial hyperresponsiveness are commonly reported as sequelae to chlorine exposure. This article constitutes the first case of a single antecedent chlorine exposure inducing progressive vocal cord dysfunction.  相似文献   
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