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Suaeda fruticosa Forssk. Ex J.F.Gmel is traditionally used for inflammatory and digestive disorders, as a carminative, and for diarrhea. This plant is widely distributed in Asia, Africa, and the Mediterranean region. Aqueous methanolic extract of S. fruticosa (Sf.Cr) was prepared and screened for phytoconstituents through qualitative and GC-MS analysis. Quantification of total phenolic and flavonoid contents was performed, while antioxidant capacity was determined by DPPH, CUPRAC, FRAP, and ABTS assays. The gastroprotective activity was assessed in an ethanol-induced ulcer model. Gastric secretory parameters and macroscopic ulcerated lesions were analyzed and scored for ulcer severity. After scoring, histopathology was performed, and gastric mucus contents were determined. Oral pre-treatment of Sf.Cr demonstrated significant gastroprotection. The gastric ulcer severity score and ulcer index were reduced while the %-inhibition of ulcer was increased dose-dependently. The Sf.Cr significantly elevated the pH of gastric juice, while a decrease in total acidity and gastric juice volume was observed. Histopathology demonstrated less oedema and neutrophil infiltration in gastric mucosa of rats pre-treated with the Sf.Cr in comparison to ethanol-intoxicated animals. Furthermore, the gastric mucus contents were increased as determined by alcian blue binding. Sf.Cr showed marked gastroprotective activity, which can be attributed to antioxidant, antisecretory, and cytoprotective effects.  相似文献   
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Enzymes that degrade pectin are called pectinases. Pectinases of microbial origin are used in juice clarification as the process is cost-effective. This study screened a pectinase-producing bacterium isolated from soil and identified as Bacillus subtilis 15A B-92 based on the 16S rRNA molecular technique. The purified pectinase from the isolate showed 99.6 U/mg specific activity and 11.6-fold purity. The molecular weight of the purified bacterial pectinase was 14.41 ± 1 kD. Optimum pectinase activity was found at pH 4.5 and 50 °C, and the enzyme was 100% stable for 3.5 h in these conditions. No enzymatic inhibition or activation effect was seen with Fe2+, Ca2+, or Mg2+. However, a slight inhibition was seen with Cu2+, Mn2+, and Zn2+. Tween 20 and 80 slightly inhibited the pectinase, whereas iodoacetic acid (IAA), ethylenediaminetetraacetate (EDTA), urea, and sodium dodecyl sulfate (SDS) showed potent inhibition. The bacterial pectinase degraded citrus pectin (100%); however, it was inactive in the presence of galactose. With citrus pectin as the substrate, the Km and Vmax were calculated as 1.72 mg/mL and 1609 U/g, respectively. The high affinity of pectinase for its substrate makes the process cost-effective when utilized in food industries. The obtained pectinase was able to clarify orange and apple juices, justifying its application in the food industry.  相似文献   
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In this paper, some nonlocal in time differential inequalities of Sobolev type are considered. Using the nonlinear capacity method, sufficient conditions for the nonexistence of nontrivial global classical solutions are provided.  相似文献   
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Abstract

In continuing our efforts to develop new potent anticancer candidates, a new series of 9-ethylcarbazoles carrying at position 3 various heterocyclic substituents such as 2-imino-2H-chromenes 5a–e, 2-oxo-2H-chromenes 6a–e, 3-imino-3H-benzo[f]chromene 8, 3-oxo-3H-benzo[f]chromene 9, 2-pyridones 11, 14, pyrazole 19, pyrimidine 23, pyrido[1,2-a]pyrimidine 27, 2H-pyran-2-one 30, and pyrano[2,3-d]pyrimidinetrione 34 were efficiently synthesized, characterized and evaluated for their in vitro antitumor activity. The mechanism for the synthesis of compounds was also discussed. Most of the synthesized compounds were displayed the considerable anticancer activities against three human tumor cells lines, in particular, colon carcinoma (HCT-116), hepatocellular carcinoma (HepG-2) and breast cancer (MCF-7). Compound 6d proves as most active molecule in this study with special effectiveness against the human HCT-116 and HepG-2 as its IC50 values are 1.50, 0.90?μM, respectively, when doxorubicin is compared. Compound 34 was also found to have high activity against HepG-2, HCT-116 and moderate activity against MCF-7.  相似文献   
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Journal of Thermal Analysis and Calorimetry - The influence of four different quantities of niobium (Nb) on some physical and chemical properties of Ni-Ti alloy was examined in this study....  相似文献   
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In this work, β-CD-based polyurethane copolymers (β-CDPU) have been prepared by reacting β-CD with hexamethylene diisocyanate as cross-linked agent in dry DMF. This polymer showed high selectivity for preconcentration of Pb(II) at trace level prior to its flame atomic absorption spectrometric determination. The effect of several parameters such as pH, flow rate of sample, eluent kind and volume was investigated. The adsorption behaviors and mechanisms of Pb(II) on the samples were also studied. The maximum adsorption amount of Pb(II) was 8 mg g?1 with the preconcentration factor of 250 for Pb(II). The Langmuir isotherm was proved to describe the adsorption data better than the Freundlich isotherm and a pseudo-first-order kinetic model fits the adsorption kinetic processes well. The calibration curve was linear in the range of (3–200 ng mL?1) with a correlation coefficient of 0.9996. The limit of detection based on three times the standard deviation of the blank was 1.15 ng mL?1. The relative standard deviations for the determination of 10 and 100 ng mL?1 of Pb(II) were 3.60 and 0.43 % (n = 10), respectively. The method was successfully applied to the determination of lead in some environmental samples such as Tehran and Bushehr drinking water, river water and dust samples.  相似文献   
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In this paper, a variable-order fractional derivative nonlinear cable equation is considered. It is commonly accepted that fractional differential equations play an important role in the explanation of many physical phenomena. For this reason we need a reliable and efficient technique for the solution of fractional differential equations. This paper deals with the numerical solution of class of fractional partial differential equation with variable coefficient of fractional differential equation in various continues functions of spatial and time orders. Our main aim is to generalize the Chebyshev cardinal operational matrix to the fractional calculus. Finally, illustrative examples are included to demonstrate the validity and applicability of the presented technique.  相似文献   
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