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41.
The aim of this study was to determine the serum concentrations of selenium, vitamin E, and total- and lipid-bound sialic acid (LBSA) in lambs with white muscle disease (WMD) before and after treatment with a commercial preparation containing selenite and vitamin E. Fifteen lambs with WMD and ten control animals were used as research materials. Blood samples were collected from both groups before- and 1 month after treatment for Se analysis by fluorimetry, whereas vitamin E and sialic acid were measured by HPLC and spectrophotometry, respectively. Compared to controls, in the diseased animals, there was a significant increase of serum total sialic acid (TSA) and LBSA, together with significant decreases of serum Se and vitamin E concentrations (p < 0.001). One month after treatment, a reversal of trend was observed with decreases of TSA and LBSA and increases of Se and vitamin E concentrations. The TSA and LBSA levels, however, remained significantly higher than those of the controls, p < 0.05 and 0.001, respectively. The Se and vitamin E concentrations of the treated animals were the same as those of controls. This is the first study on total and LBSA concentrations in lambs with WMD, showing that these markers can be used in the prognosis of the disease.  相似文献   
42.
The morphology and ligninolytic enzyme production of a recently isolated wood-degrading fungus Trichophyton rubrum LSK-27 was investigated. In submerged cultures, the organism appeared to be an efficient manganese peroxidase (MnP) producer. When grown in baffled and unbaffled shake flasks with three different working volume/total volume ratios (WV/TV 10, 25 and 50%), the organism displayed notable morphological differences, with variations in pellet shape and size. Cultivation in baffled flasks with 25% WV/TV resulted in higher MnP and also laccase production as well as an earlier appearance of these enzymes in culture broth. However, oxygen limitation conditions inhibited MnP and laccase production and resulted in considerable changes in the morphology of this fungus.  相似文献   
43.
In vitro and in vivo studies have proven strontium to be an osteoinductive trace element. The effect of strontium ranelate (SR) on H2O2-induced apoptosis of CRL-11372 cells and optimization of its anti-apoptotic dose were the aims of this study. After 1 h of pretreatment with SR 1 μM, 50 μM, 100 μM, 500 μM, and 1,000 μM concentrations, CRL-11372 osteoblasts were exposed to 100 μM H2O2 for periods of 6–12 h. The same experiments were repeated without H2O2. The apoptotic index and viability of cells were assessed quantitatively with a fluorescent dye and qualitatively with agarose gel electrophoresis. Concentrations of 1–100 μM of SR with a 6-h treatment and only 1 μM concentration with a 12-h treatment inhibited the apoptotic effect of H2O2 on cultured osteoblasts significantly (P < 0.05). SR was shown to inhibit H2O2-induced apoptosis of CRL-11372 cells in a dose-dependent manner.  相似文献   
44.
Extracellular proteases produced by Scytalidium thermophilum, grown on microcrystalline cellulose, were most active at pH 6.5–8 and 37–45 °C when incubated for 60 min. Highest protease activity was at day 3 where endoglucanase activity was low. Protease activity measurements with and without the protease inhibitors, p-chloromercuribenzoate, PMSF, antipain, E-64, EDTA and pepstatin A, suggest production of thiol-containing serine protease and serine proteases. Endoglucanase and Avicel-adsorbable endoglucanase activity in culture medium was not significantly affected by protease inhibitors.  相似文献   
45.
doi:10.1111/j.1741‐2358.2009.00321.x
Flexural properties of repaired heat‐polymerising acrylic resin after wetting with monomer and acetone Objectives: Repair strength can be improved by treating fractured surfaces of a denture. Background: This study investigated flexural properties of heat‐polymerised acrylic resin specimens repaired with auto‐polymerising and visible light curing (VLC) resins after the repair surfaces were wetted with monomers or acetone. Materials and Methods: Fifty‐four specimens (65 × 10 × 2.5 mm) were prepared and 48 of them were sectioned to simulate denture fracture. Butt‐joint designed repair surfaces were wetted with heat‐, auto‐polymerising monomers and acetone for 180 s and repaired with auto‐polymerising and VLC resins. After repairs, specimens were subjected to three‐point bending test and flexural strength, strain, fracture load, modulus of elasticity and deflection values were recorded. Data were analysed with Student t and LSD tests (p ≤ 0.05). Results: Overall flexural strength, strain, fracture load and deflection values of specimens repaired with VLC resin were significantly higher than the specimens repaired with auto‐polymerising resin for all types of wetting agent (p < 0.05). Within the wetting agents, heat‐ and auto‐polymerising monomers produced the best mechanical properties, while wetting with acetone did not provide superior effect over both monomers. Conclusion: In clinical use, wetting the repair surfaces may result in stronger repairs. The use of bonding agent in VLC resin repairs in combination with wetting agent results in improved flexural properties.  相似文献   
46.
47.
Glutathione S‐transferases (GSTs) are the superfamily of multifunctional detoxification isoenzymes and play an important role in cellular signaling. In the present study, potential inhibition effects of chalcones were tested against human GST. For this purpose, GST was purified from human erythrocytes with 5.381 EU?mg?1 specific activity and 51.95% yield using a GSH–agarose affinity chromatographic method. The effects of chalcones on in vitro GST activity were tested at various concentrations. Ki constants of chalcones were found in the range of 7.76–41.93 μM. According to the results, 4‐fluorochalcone showed a better inhibitory effect compared with the other compounds. The inhibition mechanisms of 2'‐hydroxy‐4‐methoxychalcone and 4‐methoxychalcone were noncompetitive, whereas the inhibition mechanisms of 4'‐ hydroxychalcone, 4‐ fluorochalcone, and 4,4'‐ diflurochalcone were competitive.  相似文献   
48.
Obstructive sleep apnea syndrome (OSAS) is a sleep disorder characterized with upper airway obstructions. Some studies showed cognitive and electrophysiological changes in patients with OSAS; however, contradictory results were also reported. The purpose of the present study was twofold: (1) to investigate cognitive changes in severe OSAS patients by using neuropsychological tests and electrophysiological methods together, (2) to investigate influence of hypoxemia levels on cognition. Fifty-four severe OSAS patients and 34 age-, gender- and education matched healthy subjects were participated. OSAS patients were further divided into two subgroups according to minimum oxygen saturation levels. All participants underwent a detailed neuropsychological test battery. A classical visual oddball task was used to elicit ERP P300 and mean P300 amplitudes were measured from Fz, Cz and Pz electrode sites. OSAS patients showed reduced mean P300 amplitudes up to 43–51% on all electrode sites compared to healthy controls. Subgroup analysis revealed significant differences in neuropsychological test scores between healthy controls and high hypoxemia OSAS group, as well as between low and high hypoxemia groups. Moreover, both low and high hypoxemia OSAS groups had lower P300 amplitudes compared with healthy controls. P300 amplitudes showed a gradual decline in parallel with increasing hypoxemia severity; however, the difference between high and low hypoxemia OSAS groups did not reach significance. Moderate correlations were found between sleep parameters, neuropsychological test scores and P300 amplitudes. These results suggest that electrophysiological measures could be better indicators of cognitive changes than neuropsychological tests in OSAS, particularly in mildly affected patients.  相似文献   
49.
Propolis is a multi-functional bee product rich in polyphenols. In this study, the inhibitory effect of Anatolian propolis against SARS-coronavirus-2 (SARS-CoV-2) was investigated in vitro and in silico. Raw and commercial propolis samples were used, and both samples were found to be rich in caffeic acid, p-coumaric acid, ferulic acid, t-cinnamic acid, hesperetin, chrysin, pinocembrin, and caffeic acid phenethyl ester (CAPE) at HPLC-UV analysis. Ethanolic propolis extracts (EPE) were used in the ELISA screening test against the spike S1 protein (SARS-CoV-2): ACE-2 interaction for in vitro study. The binding energy values of these polyphenols to the SARS-CoV-2 spike and ACE-2 protein were calculated separately with a molecular docking study using the AutoDock 4.2.6 program. In addition, the pharmacokinetics and drug-likeness properties of these eight polyphenols were calculated according to the SwissADME tool. The binding energy value of pinocembrin was highest in both receptors, followed by chrysin, CAPE, and hesperetin. Based on the in silico modeling and ADME (absorption, distribution, metabolism, and excretion) behaviors of the eight polyphenols, the compounds exhibited the potential ability to act effectively as novel drugs. The findings of both studies showed that propolis has a high inhibitory potential against the Covid-19 virus. However, further studies are now needed.  相似文献   
50.
Pomatoschistus anatoliae sp. n. is described from estuary of Göksu River on the Mediterranean coast of the Anatolia. It is distinguished from its congeners by the suborbital papilla pattern, meristic, and ecological features. DNA barcoding based on COI sequences revealed that there is a high nucleotide sequence divergence to the nearest neighbour. Kimura’s two parameter distances between P. anatoliae sp. n. and other species of Pomatoschistus and Knipowitchia have found to be at least 5.1%.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:4592CF50-07B5-4C25-892F-5D009057675B  相似文献   

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