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排序方式: 共有285条查询结果,搜索用时 203 毫秒
201.
Dalia M. Rasheed Ayat M. Emad Sherifa F. Ali Sameh S. Ali Mohamed A. Farag Meselhy R. Meselhy Essam A. Sattar 《Journal of Food Biochemistry》2021,45(6):e13741
Hydroxyl radical (•OH) scavenging capacity of aqueous dill (Anethum graveolens L.) shoot (ADSh) extract was assessed using electron paramagnetic resonance (EPR) spectroscopy. ADSh extract (at concentrations of 0.5 and 10 mg/ml) exerted high (OH) radical scavenging power. ADSh extract was further fractionated on Diaion HP-20 column to yield five fractions. EPR spin-trapping assay revealed fraction 4 (eluted with 75% aq. MeOH) to possess (•OH) radical scavenging capacity over a concentration range (0.01–10 mg/ml), whereas fraction 2 (eluted with 25% aq. MeOH) appeared to be pro-oxidant at concentration 0.01 mg/ml. UPLC-PDA-ESI-MS metabolite profiling of ADSh extract revealed 87 metabolites, of which 64 compounds were identified in fraction 4, the most active fraction. Furthermore, ADSh extract demonstrated a hepatoprotective effect against acetaminophen (APAP)-induced hepatotoxicity in rats. Pretreatment of rats with ADSh extract (200 mg/kg b.wt) markedly attenuated the increased in the serum hepatic enzyme levels. It also increased free glutathione level and total antioxidant capacity in the serum of treated rats. [Correction added on May 3, 2021, after first online publication: "rates" has been changed to "rats" in the previous sentence.] Additionally, levels of (TNF-α and IL-1β) were back to almost normal levels compared to the control group. The above findings suggest that ADSh extract has a protective effect against APAP-induced liver damage. 相似文献
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Ghulam Gilanie Usama Ijaz Bajwa Mustansar Mahmood Waraich Zulfiqar Habib 《International journal of imaging systems and technology》2019,29(4):531-538
Reliable brain tumor radiology is one of the serious mortality issues of medical hospitals and on priority of healthcare departments. In this research, the presence of brain tumor and its type (if exists) is automatically diagnosed from magnetic resonance imaging (MRI). The first step is most important where suitable parameters from Gabor texture analysis are extracted and then classified with a support vector machine. The drive of this research activity is to verify robustness of the proposed model on cross datasets, so that it could deal with variability and multiformity present in MRI data. Further to this, the developed approach is able to deploy as a real application in the local environment. Therefore, once a model has been trained and tested on an openly available benchmarked dataset, it is retested on a different dataset acquired from a local source. Standard evaluation measures, that is, accuracy, specificity, sensitivity, precision, and AUC-values have been used to evaluate the robustness of the proposed method. It has been established that the proposed method has the ability to deal with multiformity, variability, and local medical traits present in brain MRI data. 相似文献
204.
WA Scott D Brambilla E Siwak C Beatty J Bremer RW Coombs H Farzadegan SA Fiscus SM Hammer FB Hollinger N Khan S Rasheed PS Reichelderfer 《Canadian Metallurgical Quarterly》1996,34(9):2312-2315
Quantitative microculture assays of cryopreserved human immunodeficiency virus type 1-infected cell suspensions and culture supernatants were compared among seven assays sites. There was no significant change in titer during 1 year of storage. The overall standard deviation for infected cell suspensions was approximately 0.8 log10 virus titer. A method for detecting deviant assay results was developed and was used to identify two donor cell preparations (n = 54) that gave consistently low titers. 相似文献
205.
RS DiPaola RE Weiss KB Cummings FM Kong RL Jirtle M Anscher J Gallo S Goodin S Thompson Z Rasheed J Aisner MB Todd 《Canadian Metallurgical Quarterly》1997,3(11):1999-2004
The objective of this study was to test the hypothesis that 13-cis-retinoic acid (CRA) and alpha-interferon (IFN-alpha) have antitumor activity in patients with early recurrence of prostate cancer measured by rising prostate-specific antigen (PSA) after local therapy, and that this activity is associated with the increase of plasma transforming growth factor beta1 (TGF-beta1). Thirty patients with a PSA > 7 ng/ml that increased >0.4 ng/ml/month after initial radiation therapy or a PSA > 2.0 ng/ml after prostatectomy were treated with 1 mg/kg/day of CRA and 3 million units of IFN-alpha administered three times per week. Patients were followed clinically with serum measurements of PSA and assessment of toxicity. Biological activity of CRA and IFN-alpha was assessed by the measurement of plasma TGF-beta1. Twenty-six percent of patients had a partial (50% decrease maintained for 1 month) or minimal (<50% decrease maintained for 1 month) biochemical response of PSA, with a median decrease of 23% (11-55%) at 3 months. Plasma TGF-beta1 levels increased with CRA and IFN-alpha therapy and correlated with a decrease in PSA; patients with a decrease in PSA had a 151% increase in TGF-beta1 compared to 27% in patients without a decrease in PSA (P = 0.04). CRA and IFN-alpha can produce transient reduction or stabilization of PSA. The measurement of plasma TGF-beta1 at 1 month of therapy correlates with changes in PSA and may represent a useful marker for the biological effect of these agents; further analysis in larger numbers of patients and methods to optimize these effects should be explored. 相似文献
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207.
Multiobjective GA optimization using reduced models 总被引:1,自引:0,他引:1
D. Chafekar Liang Shi K. Rasheed Jiang Xuan 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2005,35(2):261-265
In this paper, we propose a novel method for solving multiobjective optimization problems using reduced models. Our method, called objective exchange genetic algorithm for design optimization (OEGADO), is intended for solving real-world application problems. For such problems, the number of objective evaluations performed is a critical factor as a single objective evaluation can be quite expensive. The aim of our research is to reduce the number of objective evaluations needed to find a well-distributed sampling of the Pareto-optimal region by applying reduced models to steady-state multiobjective GAs. OEGADO runs several GAs concurrently with each GA optimizing one objective and forming a reduced model of its objective. At regular intervals, each GA exchanges its reduced model with the others. The GAs use these reduced models to bias their search toward compromise solutions. Empirical results in several engineering and benchmark domains comparing OEGADO with two state-of-the-art multiobjective evolutionary algorithms show that OEGADO outperformed them for difficult problems. 相似文献
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Mohamed Seddik Mahmoud Bougi Syrine Baklouti Mohamed Abdul Rasheed Rao PLS Syed Zaheer Hasan Mohamed Ksibi 《Petroleum Science and Technology》2013,31(23):2029-2036
AbstractIn this work we attempt to identify the geomicrobial fingerprints alongside with trace metals anomalies, and to explore whether the geomicrobial signatures are correlated with trace metals in El Hajeb oilfield in Tunisia. 51 soil samples are collected in grid pattern of 1?×?1?km interval. After incubating soil samples with propane in mineral salt medium, we count the propane oxidizing bacteria abundance ranged from nil to 2.44?×?105 cfu/g of soil sample. It was found that the concentrations of trace elements are enormously increased when they are compared with the natural background concentrations of metals in soils. 相似文献