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91.
92.
Jung Eui-Gil Han Kook-Il Kwon Hyun-Jung Patnaik Bharat Bhusan Kim Wan-Jong Hur Gang Min Nam Kung-Woo Han Man-Deuk 《Archives of pharmacal research》2015,38(6):973-983
Archives of Pharmacal Research - Sappanchalcone, a bioactive flavonoid isolated from the heartwood of Caesalpinia sappan L. possesses anti-inflammatory effects. We studied the efficacy of... 相似文献
93.
94.
Tuong A. To Chau B. Tran Ngoc T. H. Nguyen Hai H. T. Nguyen Anh T. Nguyen Anh N. Q. Phan Nam T. S. Phan 《RSC advances》2018,8(31):17477
A copper-based framework Cu2(OBA)2(BPY) was synthesized and used as a recyclable heterogeneous catalyst for the synthesis of β-sulfonylvinylamines from sodium sulfinates and oxime acetates via direct C–S coupling reaction. The transformation was remarkably affected by the solvent, and chlorobenzene emerged as the best option. This Cu-MOF displayed higher activity than numerous conventional homogeneous and MOF-based catalysts. The catalyst was reutilized many times in the synthesis of β-sulfonylvinylamines without considerably deteriorating in catalytic efficiency. These β-sulfonylvinylamines were readily converted to the corresponding β-ketosulfones via a hydrolysis step with aqueous HCl solution. To the best of our knowledge, this direct C–S coupling reaction to achieve β-sulfonylvinylamines was not previously conducted with a heterogeneous catalyst.Cu2(OBA)2(BPY) was used as catalyst for the synthesis of β-sulfonylvinylamines from sodium sulfinates and oxime acetates. These β-sulfonylvinylamines were readily converted to corresponding β-ketosulfones via a hydrolysis step. 相似文献
95.
YongSung Kwon Shivshankar Chaudhari ChaEun Kim DaHae Son JiHwan Park MyungJun Moon MinYoung Shon YouIn Park SeungEun Nam 《RSC advances》2018,8(37):20669
Ag-exchanged NaY zeolite (Ag-NaZ) particles were prepared by ion exchange and introduced to a polyvinyl alcohol (PVA) membrane cross-linked with polyacrylic acid (PAA) for the pervaporation dehydration of an isopropanol (IPA) aqueous mixture. The Ag-exchanged NaY zeolite particles were characterized by FE-SEM, EDS, BET, and XRD studies. The prepared Ag-NaZ-loaded PVA/PAA composite membrane was characterized by FE-SEM, XRD, a swelling study, and contact angle measurements. Pervaporation characteristics were investigated in terms of Ag-NaZ concentrations within PVA/PAA membranes using diverse feed solution conditions. The preferential sorption of IPA/water mixtures for Ag-NaZ-introduced membranes were also determined by calculating the apparent activation energies of IPA and water permeation, respectively. As a result, flux and selectivity increased with the Ag-NaZ concentration to 5 wt% in the membrane. Optimum pervaporation performance was observed in a 5 wt% Ag-NaZ-incorporated membrane with a flux equal to 0.084 kg m−2 h−1 and a separation factor of 2717.9 at 40 °C from an 80 wt% IPA aqueous feed solution.Ag-exchanged NaY zeolite (Ag-NaZ) particles were prepared by ion exchange and introduced to a polyvinyl alcohol (PVA) membrane cross-linked with polyacrylic acid (PAA) for the pervaporation dehydration of an isopropanol (IPA) aqueous mixture. 相似文献
96.
Dung T. Nguyen Lan T. Pham Ha T. T. Le Minh X. Vu Hanh T.
M. Le Huong T. M. Le Nam H. Pham Le T. Lu 《RSC advances》2018,8(35):19707
Magnetic nanoparticles have received much interest for their application in wastewater treatment because of their easy retrieval and reuse. However, the methods used to synthesise high saturation magnetization magnetic nanoparticles require expensive and pure precursors. In the current study, we explore the potential for using spent pickling liquor, a wastewater solution from steel factories, as the iron precursor for preparing iron oxide nanoparticles. Here, magnetic Fe3O4 nanoparticles were synthesized via the oxidation–precipitation of spent pickling liquors using a saturated solution of calcium hydroxide at room temperature. The Fe3O4 nanoparticles were then modified with antibacterial polyguanidine to form a nanocomposite. It was found that monodisperse magnetic Fe3O4 nanoparticles with a size in the range 20–30 nm and a high saturation magnetization value of 73.9 emu g−1 were synthesised. The Fe3O4 nanoparticles were successfully encapsulated with polyguanidine to form an Fe3O4/polyguanidine nanocomposite. FT-IR and TGA analysis results indicated the presence of the polymer on the Fe3O4 surface and the polymer content in the nanocomposite was about 15% (w/w). The Fe3O4/polyguanidine nanocomposite exhibited strong antibacterial activity against Escherichia coli (E. coli), demonstrating its potential for use in disinfecting wastewater.An Fe3O4/polyguanidine nanocomposite with strong antibacterial activity was prepared from Fe3O4 nanoparticles, using spent pickling liquors as the iron source, which were then encapsulated with polyguanidine. 相似文献
97.
Nam Kwangwoo Kim Nayoung Song Hyun Joo Baik Gwang Ho Choi Suck Chei Kim Hyun Jin Lee Ju Yup Park Kyung Sik Park Sun-Young Park Seun Ja 《Journal of gastroenterology》2021,56(6):537-546
Journal of Gastroenterology - The overlap between functional dyspepsia (FD) and irritable bowel syndrome (IBS) is associated with more severe gastrointestinal (GI) symptoms and lower quality of... 相似文献
98.
Jeong YH Choi KJ Song JM Hwang ES Park KM Nam GB Kim JJ Kim YH 《Clinical cardiology》2008,31(4):172-178
BACKGROUND: Due to the absence of differential guidelines for heart failure with tachyarrhythmia, it is difficult to diagnose tachycardia-induced cardiomyopathy (TIC) at the initial visit. Furthermore, clinical outcomes of rate versus rhythm control in TIC are unclear. HYPOTHESIS: Because the etiology of TIC is different from dynamic cardiomyoplasty (DCMP), differential parameters may be present. METHODS: We assessed 21 patients with TIC (15 men; mean age, 50+/-14 years) and 21 control patients with idiopathic DCMP. We assessed clinical courses, echocardiographic parameters, as well as outcomes by treatment. RESULTS: In the TIC group, the related tachyarrhythmias were atrial fibrillation (n=12), atrial flutter (n=5), atrial tachycardia (n=3) and paroxysmal supraventricular tachycardia (n=1). After treatment, all patients became asymptomatic and the ejection fraction (EF) improvement (DeltaEF>or=15%) was observed in all patients (left ventricular ejection fraction [LVEF], 30+/-11%initial versus 58+/-6%last). In the idiopathic DCMP group, no patient showed EF improvement (EF increase相似文献
99.
N.J. Yoo J.W. Lee E.G. Jeong Y.H. Soung S.W. Nam J.Y. Lee S.H. Lee 《Digestive and liver disease》2006,38(9):683-687
BACKGROUND: It has become clear that, together with proliferation, deregulation of apoptosis plays a pivotal role in tumourigenesis. BAD is a pro-apoptotic Bcl-2 family protein and regulates the intrinsic apoptosis pathway. Phosphorylation of BAD inhibits the apoptosis function of BAD. AIMS: To investigate whether alteration of the phospho-BAD protein and somatic mutation of BAD gene are characteristics of human hepatocellular carcinoma. PATIENTS AND METHODS: We analysed the expression of phospho-BAD in 20 hepatocellular carcinomas by immunohistochemistry. Also, we analysed the BAD gene for the detection of somatic mutations by a single-strand conformation polymorphism assay in 69 hepatocellular carcinomas. RESULTS: Phospho-BAD expression in the non-tumour hepatocytes was seen in all of the hepatocellular carcinomas, while the expression in the cancer cells was observed in 15% (3 of the 20) of the hepatocellular carcinomas. There was no somatic mutation of BAD Bcl-2 homology 3 (BH3) domain in the 69 hepatocellular carcinomas. CONCLUSIONS: The data showed that loss of phospho-BAD expression, but not BAD gene mutation, is a feature of hepatocellular carcinomas. The decreased expression of phospho-BAD in the hepatocellular carcinoma cells compared to the non-tumour hepatocytes suggests that loss of phospho-BAD expression may play a role in hepatocellular tumourigenesis. 相似文献
100.