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排序方式: 共有357条查询结果,搜索用时 15 毫秒
31.
Gholipour Akram Shakerian Farshad Zahedmehr Ali Oveisee Maziar Maleki Majid Mowla Seyed Javad Malakootian Mahshid 《Molecular biology reports》2022,49(10):9267-9273
Molecular Biology Reports - Coronary artery disease (CAD), is the leading cause of mortality and morbidity worldwide. Tenascin-C (TNC) with high expression levels in inflammatory and cardiovascular... 相似文献
32.
Kafeel Ahmad Asma Ashfaq Muhammad Ashraf Nudrat Aisha Akram Sumaira Yasmin 《人类与生态风险评估》2015,21(4):1109-1122
Dietary exposure to heavy metals (viz., Ni, As, Fe, Cr, Mn, Co, Mo, Cu, Zn, Se, Cd, and Pb) has been recognized as a potential hazard to human health. This study investigates the level of contamination at two different sites in Pakistan, one irrigated with canal water (Site-I) and the other with urban wastewater (Site-II). At Site-II, irrigation with wastewater resulted in a significant increase in heavy metals and metalloids in soil and a subsequent build-up in two vegetables selected for study (Solanum tuberosum [potato] and Pisum sativum [pea]). Results showed that mean concentrations of heavy metals and metalloids in soil at Site-I were lower than those of Site-II. Mean concentrations of As and Cd in soil at both sites and for both vegetables were found above maximum permissible levels, while for both vegetables As at both sites and Cd, Mo, and Pb exceeded the suggested maximum levels for vegetables. High levels of some metals in the soils and vegetables could be due to unnecessary use of fertilizers and disposable water for irrigating the soils and the environmental cues prevalent in the areas, such as presence of ions that may bind the metals, often play an important role in uptake. 相似文献
33.
Reza Heidari Hossein Niknahad Akram Jamshidzadeh Negar Azarpira Mandana Bazyari Asma Najibi 《Journal of biochemical and molecular toxicology》2015,29(4):173-181
Liver injury is a deleterious adverse effect associated with methimazole administration, and reactive intermediates are suspected to be involved in this complication. Glyoxal is an expected reactive intermediate produced during methimazole metabolism. Current investigation was undertaken to evaluate the role of carnosine, metformin, and N‐acetyl cysteine as putative glyoxal (carbonyl) traps, against methimazole‐induced hepatotoxicity. Methimazole (100 mg/kg, intraperitoneally) was administered to intact and/or glutathione (GSH)?depleted mice and the role of glyoxal trapping agents was investigated. Methimazole caused liver injury as revealed by an increase in serum alanine aminotransferase and aspartate aminotransferase. Moreover, lipid peroxidation and protein carbonylation occurred significantly in methimazole?treated animals’ liver. Hepatic GSH reservoirs were decreased, and inflammatory cells infiltration was observed in liver histopathology. Methimazole?induced hepatotoxicity was severe in GSH‐depleted mice and accompanied with interstitial hemorrhage and necrosis of the liver. Glyoxal trapping agents effectively diminished methimazole‐induced liver injury both in intact and/or GSH?depleted animals. 相似文献
34.
Gasmelseed A 《Computer methods in biomechanics and biomedical engineering》2011,14(7):665-671
In electromagnetic dosimetry, anatomical human models are commonly obtained by segmentation of magnetic resonance imaging or computed tomography scans. In this paper, a human head model extracted from thermal infrared images is examined in terms of its applicability to specific absorption rate (SAR) calculations. Since thermal scans are two-dimensional (2D) representation of surface temperature, this allows researchers to overcome the extensive computational demand associated with 3D simulation. The numerical calculations are performed using the finite-difference time-domain method with mesh sizes of 2 mm at 900 MHz plane wave irradiation. The power density of the incident plane wave is assumed to be 10 W/m(2). Computations were compared with a realistic anatomical head model. The results show that although there were marked differences in the local SAR distribution in the various tissues in the two models, the 1 g peak SAR values are approximately similar in the two models. 相似文献
35.
Gasmelseed A 《Electromagnetic biology and medicine》2011,30(3):136-145
This article describes the analysis of electromagnetic energy absorption properties of models of the human eye with common visual disorders. The investigation addresses two types of visual disorders, namely hyperopia (or farsightedness) and myopia (or nearsightedness). Calculations were carried out using plane multilayered method with common wireless communication frequencies of 900, 1800, and 2450?MHz. The effect of wireless radiation on the eye is studied by calculation of the specific absorption rate (SAR) in three different eye models. The results of the simulations confirmed the anticipated and more complex relationship between absorption and structural variations of the eye at these frequencies. 相似文献
36.
37.
Akram Nudrat Aisha Shafiq Fahad Ashraf Muhammad Iqbal Muhammad Ahmad Parvaiz 《Journal of Plant Growth Regulation》2021,40(3):891-905
Journal of Plant Growth Regulation - Plant biofibers are of great economic and commercial importance. Among various fiber producing crops, cotton (Gossypium hirsutum L.), hemp (Cannabis sativa L.),... 相似文献
38.
Akram Alian 《Journal of molecular biology》2009,388(4):785-291
Escherichia coli pseudouridine synthase RluF is dedicated to modifying U2604 in a stem-loop of 23S RNA, while a homologue, RluB, modifies the adjacent base, U2605. Both uridines are in the same RNA stem, separated by ∼ 4 Å. The 3.0 Å X-ray crystal structure of RluF bound to the isolated stem-loop, in which U2604 is substituted by 5-fluorouridine to prevent catalytic turnover, shows RluF distinguishes closely spaced bases in similar environments by a selectivity mechanism based on a frameshift in base pairing. The RNA stem-loop is bound to a conserved binding groove in the catalytic domain. A base from a bulge in the stem, A2602, has folded into the stem, forcing one strand of the RNA stem to translate by one position and thus positioning U2604 to flip into the active site. RluF does not modify U2604 in mutant stem-loops that lack the A2602 bulge and shows dramatically higher activity for a stem-loop with a mutation designed to facilitate A2602 refolding into the stem with concomitant RNA strand translation. Residues whose side chains contact rearranged bases in the bound stem-loop, while conserved among RluFs, are not conserved between RluFs and RluBs, suggesting that RluB does not bind to the rearranged stem loop. 相似文献
39.
Puxeddu I Alian A Piliponsky AM Ribatti D Panet A Levi-Schaffer F 《The international journal of biochemistry & cell biology》2005,37(3):628-636
Eosinophils play a crucial role in allergic reactions and asthma. They are also involved in responses against parasites, in autoimmune and neoplastic diseases, and in fibroses. There is increasing evidence that angiogenesis plays an important role in these processes. Since eosinophils are known to produce angiogenic mediators, we have hypothesized a direct contribution of these cells to angiogenesis. The effect of human peripheral blood eosinophil sonicates on rat aortic endothelial cell proliferation (in vitro), rat aorta sprouting (ex vivo) and angiogenesis in the chick embryo chorioallantoic membrane (in vivo) have been investigated. To determine whether eosinophil-derived vascular endothelial growth factor influences the eosinophil pro-angiogenic activity, eosinophil sonicates were incubated with anti-vascular endothelial growth factor antibodies and then added to the chorioallantoic membrane. Vascular endothelial growth factor mRNA expression and vascular endothelial growth factor receptor density on the endothelial cells were also evaluated. Eosinophils were found to enhance endothelial cell proliferation and to induce a strong angiogenic response both in the aorta rings and in the chorioallantoic membrane assays. Pre-incubation of eosinophil sonicates with anti-vascular endothelial growth factor antibodies partially reduced the angiogenic response of these cells in the chorioallantoic membrane. Eosinophils also increased vascular endothelial growth factor mRNA production on endothelial cells. Eosinophils are able to induce angiogenesis and this effect is partially mediated by their pre-formed vascular endothelial growth factor. This strongly suggests an important role of eosinophils in angiogenesis-associated diseases such as asthma. 相似文献
40.
Lev EI Kornowski R Teplisky I Hasdai D Rechavia E Shor N Battler A Assali AR 《International journal of cardiovascular interventions》2005,7(1):41-45
The role of small molecules anti-glycoprotein (GP) IIb/IIIa pharmacotherapy during acute myocardial infarction (AMI) has not been established. The purpose of our study was to evaluate the clinical outcomes of patients sustaining AMI who underwent emergent percutaneous coronary intervention (PCI) and who were distinguished by the use of the anti-GP IIb/IIIa agent eptifibatide. We studied a consecutive group of 216 patients who underwent PCI for acute ST-elevation myocardial infarction and compared the outcomes of patients who received eptifibatide just prior and following the procedure (n=167) to those who were not on anti GP IIb/IIIa inhibitors (n=49). On average, patients treated using eptifibatide were younger and were more likely to be men, hypertensive, and smokers. The eptifibatide treated patients were less likely to have diabetes and renal failure and had worse angiographic characteristics. There were no significant differences between the groups in any of the clinical outcomes, including the composite endpoint (e.g. death, MI, repeat revascularization) and the rate of sub-acute stent thrombosis. Nonetheless, there was a non-significant trend towards lower 30 day mortality in the eptifibatide group (4.8% versus 12%, P=0.09). We concluded that in our comparative study of periprocedural administration of eptifibatide during emergent AMI angioplasty, there was a non-significant trend towards better short-term survival among eptifibatide treated patients although the composite endpoint did not differ between patients distinguished by the use of anti GP IIb/IIIa small molecule pharmacotherapy. 相似文献