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101.
Lignite fly ash was used as an additive in three different alkaline stabilisation processes and the effects on some chemical properties of wastewater sludge were investigated. The results of the study indicated that sludges added with fly ash only in a dose of 40% (on a dry weight basis) generally caused no significant differences in the sludge properties. However, ammonium-nitrate nitrogen, available phosphorus and soluble boron concentrations were slightly reduced in sludges which were added with 80% and 120% fly ash. On the other hand, alkaline stabilisation (10-15% quicklime+40-120% fly ash) and alkaline pasteurisation (10-15% quicklime+40-120% fly ash+heating at 70 degrees C for 30 min) processes caused a significant decrease in available forms of nitrogen and phosphorus and a significant increase in pH. Although a strong relationship between fly ash dosage and available nitrogen concentration was obtained in alkaline stabilisation process, no significant correlation was found between the two parameters in alkaline pasteurisation process. The results also suggested that using fly ash with doses of 40%, 80% and 120% in alkaline pasteurisation process caused no significant alteration in sludge properties. Heating and quicklime addition were expected to be the influential factors.  相似文献   
102.
Several autoantibodies found in RA are directed to epitopes in citrullinated proteins. One of them is anti modified citrullinated vimentin (Anti-MCV). We tested the value a newly developed ELISA for the detection of antibodies against a genetically modified citrullinated vimentin (anti-MCV) in comparison with an anti-CCP based ELISA system for the diagnosis of RA. Thirty-five patients with RA (mean age; 42.6 +/- 10.87 years, mean disease duration; 9.37 +/- 3.98 years) were enrolled in this study. Twenty -five ankylosing spondylitis (mean age; 35.88 +/- 6.64 years, mean disease duration; 10.25 +/- 4.61 years), and 19 healthy subjects (mean age; 40.26 +/- 5.11 years) served as controls. Anti-CCP antibodies and Anti-MCV antibodies were measured using ELISA. In all RA patients, mean anti- CCP level was 69.07 +/- 90.43 U/ml and anti-MCV level was 665.77 +/- 1040.19 U/ml. In patients with AS, the mean anti-CCP level was 10.7 +/- 5.22 U/ml and anti-MCV level was 40.54 +/- 20.15 U/ml. In healthy controls, the mean anti-CCP level was 11.11 +/- 7.65 U/ml, anti-MCV level was 23.12 +/- 12.04 U/ml. In patients with active RA, the mean serum anti-CCP level was 100.54 +/- 98.07 U/ml and anti-MCV level was 998.74 +/- 1154.93 U/ml. In patients with inactive RA, the mean serum anti-CCP level was 8.77 +/- 1.55 U/ml and anti-MCV level was 27.59 +/- 23.10 U/ml. According to these results; In patients with RA, the mean serum anti-MCV and anti-CCP levels were significantly high compared to patients with AS and healthy controls (p=0.002, p=0.001, p=0.002, p=0.001 respectively). The mean serum anti-MCV and anti- CCP levels were significantly higher in active patients with RA than in inactive patients with RA patients (p=0.001 and p=0.001 respectively). In inactive patients with RA, the mean serum anti-MCV and anti-CCP levels were similar in patients with AS and patients (p=0.484, p=0.308, p=0.09 and p=0.222 respectively). The mean serum anti-MCV levels were correlated with DAS 28 (r=0.531, p=0.001), VAS score (r=0.332, p=0.01), ESR (r=0.458, p=0.001), serum CRP levels (r=0.568, p=0.01), serum RF levels (r=0.529, p=0.001), swollen joints number (r=0.525, p=0.001) and tender joints number (r=0.638, p=0.001). As a result; measurement of serum anti-MCV levels is useful for diagnosis of RA and combined use of anti-MCV and RF may be more useful prognostic factor than either method alone, RF and anti-CCP.  相似文献   
103.
Probiotic cultures encounter oxidative conditions during manufacturing, yet protein abundance changes induced by such stress have not been characterized for some of the most common probiotics and starters. This comparative proteomics investigation focuses on the response by Lactobacillus acidophilus NCFM to H2O2, simulating an oxidative environment. Bacterial growth was monitored by BioScreen and batch cultures were harvested at exponential phase for protein profiling of stress responses by 2D gel based comparative proteomics. Proteins identified in 19 of 21 spots changing in abundance due to H2O2 were typically related to carbohydrate and energy metabolism, cysteine biosynthesis, and stress. In particular, increased cysteine synthase activity may accumulate a cysteine pool relevant for protein stability, enzyme catalysis, and the disulfide‐reducing pathway. The stress response further included elevated abundance of biomolecules reducing damage such as enzymes from DNA repair pathways and metabolic enzymes with active site cysteine residues. By contrast, a protein‐refolding chaperone showed reduced abundance, possibly reflecting severe oxidative protein destruction that was not overcome by refolding. The proteome analysis provides novel insight into resistance mechanisms in lactic acid bacteria against reactive oxygen species and constitutes a valuable starting point for improving industrial processes, food design, or strain engineering preserving microorganism viability.  相似文献   
104.
Xylanase production was performed by growing a Bacillus isolate on agricultural by-products, wheat straw, wheat bran, corn cobs and cotton bagasse. A maximum xylanase activity of 180 U/ml was obtained together with a cellulase activity of 0.03 U/ml on 4 (w/v) corn cobs. Electrophoretic analysis showed the presence of three endo--1, 4-xylanases having molecular weights of about 22, 23 and 40 kDa. Xylanolytic activity was stable up to 50 °C in the pH range of 4.5–10 and the highest activity was observed at 70 °C and pH 6.5.  相似文献   
105.
In this study, the effect of intramuscular injection of human vascular endothelial growth factor (hVEGF) on neovascularization following abdominoplasty was investigated. Twenty-four Sprague-Dawley rats were divided into four groups (n = 6). Two control groups and two experimental groups were established. Abdominoplasty was performed in all rats, with division of all the perforator vessels. In the control groups, normal saline was injected into the rectus abdominis muscle, and in the experimental groups, 100 microg of VEGF and normal saline were injected into the rectus muscle. A transverse rectus abdominis musculocutaneous (TRAM) flap was harvested on day 20 and day 40 in both the control and experimental groups. The range of viability of the TRAM flap was, respectively, 0 to 20 percent (mean, 6.7 percent) and 0 to 25 percent (mean, 14.2 percent) in both short-term and long-term control groups (no VEGF injected). The study (VEGF) group demonstrated a viability of 50 to 80 percent (mean, 70 percent) for the short-term group and 50 to 85 percent (mean, 72.5 percent) in the long-term group. No wound infection was documented, and there were no deaths during the study period. There was no statistically significant difference between the short-term and long-term divisions of the groups (p < 0.01); however, significant differences were observed between the control and experimental groups (p < 0.01). The authors concluded that VEGF injection after abdominoplasty improved the percentage of TRAM flap viability. This method of delay/revascularization could be used for the difficult problem of flap viability following abdominoplasty and for high-risk patients.  相似文献   
106.
The possibility of using xylan, as an agricultural by-product, for production of composite films in combinations with wheat gluten was investigated. Different levels of xylan (0-40% w/w) were incorporated into wheat gluten to form biodegradable composite films. Films were prepared at pH 4 and 11, and dried at either uncontrolled or controlled conditions. The mechanical properties, solubilities and water vapour transfer rate (WVTR) of the composite films were studied. Films were obtained with added xylan without decreasing film-forming quality. Xylan can be used as an additive, as much as 40% (w/w), in wheat gluten films. Changing pH, wheat gluten/xylan ratio, xylan type and drying conditions affected mechanical and solubility properties, however, WVTR was not affected by xylan additions. Wheat gluten/xylan composite films having different characteristics can be produced depending on xylan type, composition and process conditions.  相似文献   
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109.
This study investigated the effects of Onosma armeniacum K. (Boraginaceae) root extract (AR-1) on ethanol-induced stomach ulcers, and on some oxidant and antioxidant parameters, in stomach tissue in rats. The results obtained showed that AR-1 significantly inhibited ethanol-induced ulcers at 25, 50, 100 and 200 mg/kg doses. We found that 50, 100 and 200 mg/kg doses of AR-1 inhibited ulcers more effectively than did ranitidine. AR-1 at doses of 25, 50, 100 and 200 mg/kg significantly prevented the decrease in total glutathione (tGSH) level which occurs in damaged stomach tissues of rats given ethanol (control group). Only a 100 mg/kg dose of AR-1 significantly increased the glutathione S-transferase (GST) level in stomach tissue compared to the control. All doses of AR-1 except the 25 mg/kg dose eliminated the decrease in the superoxide dismutase (SOD) level in the stomach tissue of rats given ethanol. While all doses of AR-1 decreased malondialdehyde (MDA) levels significantly; all doses AR-1 except 25 mg/kg decreased myeloperoxidase (MPO) levels significantly compared to the control. The effect of AR-1 on catalase (CAT) activity was insignificant at all doses. AR-1 significantly increased nitric oxide (NO) levels at 50, 100 and 200 mg/kg doses compared to the control. Our results indicate that the protection of some antioxidant mechanisms and the inhibition of some oxidant mechanisms have a role in AR-1's antiulcer effect mechanism.  相似文献   
110.
Gundelia species are known as “Kenger-kereng dikeni” in Anatolia, and their aerial parts are consumed as food. Also, roots and seeds (disseminules) of the Gundelia species are used to prepare gum and coffee. The chemical contents of ethanol and hexane extracts of disseminules of 17 Gundelia species, 13 of them are endemic, were studied using LC/MS/MS and GC/MS. Additionally, their antioxidant potential and enzyme inhibitory capacity against acetyl- and butyryl-cholinesterase, urease, and tyrosinase were determined. The unsaturated fatty acid ratios of Gundelia species were higher than their saturated fatty acid ratio. The highest sum of oleic and linoleic acid was detected in G. tournefortii var. tenuisecta (70.42 %). β-Sitosterol, α-amyrin, 3-acetyllupeol were identified in 17 Gundelia species by GC/MS, while chlorogenic acid and luteolin by LC/MS/MS as major compounds. The ethanol and hexane extracts of G. siirtica, G. rosea, and G. mesopotamica indicated good cholinesterase inhibitory activity. Among all species, ethanol extract of G. colemerikensis exhibited the best activity in ABTS (IC50: 32.30±0.98 μg/mL), DPPH (IC50: 59.91±0.89 μg/mL), and CUPRAC (A0.5: 57.41±1.03 μg/mL) assays. Ethanol extract of G. colemerikensis also displayed the highest inhibitory activity against butyrylcholinesterase (51.14±0.25 % at 200 μg/mL), urease (51.71±1.75 % at 200 μg/mL), and tyrosinase (39.50±0.85 % at 200 μg/mL) enzymes. According to the chemometric analysis of fatty acids, four groups were observed. Therefore, it is suggested that G. colemerikensis can be used in the pharmaceutical, food, and cosmetic industries due to its antioxidant and enzyme inhibition properties.  相似文献   
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