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排序方式: 共有838条查询结果,搜索用时 15 毫秒
71.
Didem Turgut Coşan Faruk Saydam Cansu Özbayer Fulya Doğaner Ahu Soyocak Hasan Veysi Güneş İrfan Değirmenci Hülyam Kurt Mehmet Cengiz Üstüner Cengiz Bal 《Cytotechnology》2015,67(1):97-105
Hypertension is a major health problem with increasing prevalence around the world. Tannic acid is water-soluble polyphenol that is present in tea, green tea, coffee, red wine, nuts, fruits and many plant foods. It has been reported to serve as an antioxidant or a pro-oxidant depending on the type of cells and its concentration. The purpose of our study was to evaluate the effect of tannic acid on systolic blood pressure, oxidative stress and some urinary parameters in the rat model of essential hypertension. Blood pressures of all rats were measured using the tail-cuff method. The nitric oxide synthase inhibitor N (omega)-nitro-L-arginine was administered orally at a dose of 0.5 g/l/day for 15 days to rats in order to create an animal model of hypertension. Tannic acid was intraperitoneally injected at a dose of 50 mg/kg for 15 days. Superoxide dismutase, catalase activity and the concentration of malondialdehyde (MDA) were determined in blood plasma and homogenates of heart, liver and kidney. In order to evaluate renal functions, urine pH, urine volume, urine creatine, uric acid, and urea nitrogen values were measured. Compared with the hypertension group, a decrease in MDA concentrations of heart tissue (p < 0.01), urea nitrogen values (p < 0.01) and urine volumes (p < 0.001) were established in hypertension + tannic acid group. There was also a decrease in blood pressure values (20th and 30th days) of this group, but there was no a statistical difference according to hypertension group. The findings of our research show the effect of tannic acid in lowering blood pressure in hypertensive rats. 相似文献
72.
A combination of gene expression ranking and co‐expression network analysis increases discovery rate in large‐scale mutant screens for novel Arabidopsis thaliana abiotic stress genes
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73.
Sam S Kucukasik F Yenigun O Nicolaus B Oner ET Yukselen MA 《Bioresource technology》2011,102(2):1788-1794
This study reports the first systematic investigation of the flocculation dynamics of exopolysaccharides (EPSs) produced by a halophilic bacterial strain grown on pretreated molasses as fermentation substrate. The potential use of these EPSs as an easily biodegradable, natural alternative for synthetic polyelectrolytes which are widely used and contain toxic and carcinogenic monomers was investigated. Flocculating activities of the EPS samples in synthetic water, synthetic sea water and natural sea water media which were used as model raw waters were monitored via the Photometric Dispersion Analyser (PDA 2000) instrument and removals were determined by measuring residual turbidities. One of the six EPS specimens, which formed the largest flocs thus performed highest turbidity removal, exhibited flocculation performance and particle removal efficiency comparable with commercial cationic, nonionic and anionic synthetic polyelectrolytes. 相似文献
74.
Chiral Schiff-bases 3a-f based on ferrocene were designed and synthesized using solvent-free methods by mixing ferrocene carbaldehyde 1 with amino alcohols and amines 2a-f under microwave irradiation and classical method for the enantioselective nitroaldol (Henry) reaction. The Schiff-bases were obtained in shorter reaction times and improved yield under microwave irradiation method over classical method. The highest enantioselectivity was observed in ligand 3e (95% ee) when CH(2)Cl(2) was used as solvent. 相似文献
75.
In this study, effects of different starches (tapioca (TS), wheat (WS), corn (CS), potato (PS), modified corn (MCS) and modified
potato (MPS)) and gums (xanthan gum (XG), guar gum (GG), alginate (A), salep (S), locust bean gum (LBG) and carrageen (C))
on the rheological properties of model hot chocolate beverage were studied. Swelling power (SP) of the starches and water
absorption capacity (WAC) of the gums were determined. Hot chocolate beverages showed pseudoplastic behaviour. Ostwald de
Waele model accurately described flow behaviour of each beverage sample. K, n, R
2 values for Ostwald model were in the range of 4.8–160.3 mPa.sn, 0.5117–0.9745, 0.9972–0.9998, respectively. The highest synergic effect in the model was observed between the interaction
of MCS and XG. The XG-PS, XG-TS, XG-CS combinations showed the highest K and viscosity values, respectively. 相似文献
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Douglas H. Smith Peggy Winters-Digiacinto Misrach Mitiku Sara O'Rourke Faruk Sinangil Terri Wrin David C. Montefiori Phillip W. Berman 《PloS one》2010,5(8)