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71.
Shabahang L 《Pakistan journal of biological sciences: PJBS》2010,13(22):1106-1109
Erythema Multiforme (EM) is a type of allergic reaction that occurs in response to medications, infections, or different illnesses. In many cases, a definite underlying cause may not be identified. This study aimed to evaluate adult EM outpatients with regard to patients' characteristics, the disease and the underlying contributors. In this cross-sectional study, 61 adult EA outpatients referred to the Dermatology Clinic of Tabriz Sina Hospital were recruited during a 12-month period (January 2009-January 2010). The diagnosis was made based on clinical and morphologic grounds. Age, sex, types of EA, location and type of the lesions and the underlying causes were documents. An infectious etiology was suspected when a preceding illness was noticed without drug ingestion within 1 week prior to the onset of the rash. A drug related to the condition was defined as every drug that has been taken during 21 days prior to the onset of any symptoms. There were 34 males and 27 females with a mean age of 26.8 +/- 15.3 (18-57) years enrolled. The EM was minor in 62.3% and major in 37.7% of patients. The upper limb was involved in all patients. The lesions were maculo-papular, vesiculobullous and bullous in 83.6, 13.1 and 3.3% cases, respectively. Drugs and herpes simplex were the main causes in 49.2 and 16.4% of patients, respectively. The disease was idiopathic in 34.4%. The underlying drugs were sulfonamides in 12 cases (19.7%), penicillin in 5 cases (8.2%), salicylic acid, aspirin, cimetidine and amoxicillin each one in 3 cases (4.9%) and barbiturate in 1 case (1.6%). Five cases (8.2%) were recurrent EM including 4 males and 1 female, 3 idiopathic and 2 cases due to sulfonamides. 相似文献
72.
Seyed Hassan Eftekhar-Vaghefi Leila Zahmatkesh Parvin Salehinejad Shahin Totonchi Ali Shams-Ara 《Iranian Biomedical Journal》2015,19(2):82-90
Background:
Retinoic acid as one of the most important regulators for cell differentiation was examined in this study for differentiation of human umbilical mesenchymal cells (hUCM).Methods:
After isolation, hUCM were evaluated for mesenchymal stem cell properties by flow cytometry and alkaline phosphatase assay. Also, doubling time of the cells and their differentiation potential into adipogenic and osteogenic cells were tested. hUCM were then cultured with different concentrations of retinoic acid, and on days 1, 7, and 12, the percentage of differentiated cells was determined by immunostaining for nestin, anti-microtubule associated protein 2 (MAP2), glutamic acid decarboxylase (GAD), and gamma-aminobutyric acid (GABA) markers.Results:
The isolated cells were negative for the hematopoietic markers and positive for the mesenchymal markers. They showed the population doubling time 60 ± 3 hours and differentiated into osteogenic and adipogenic cells. A descending trend in nestin and an ascending trend in MAP2, GAD, and GABA expression were observed from the first day until the last day between different concentrations of retinoic acid.Conclusion:
hUCM cells may have the potential to differentiate into neural cells in the presence of different incubation period and concentration of retinoic acid.Key Words: Cell differentiation, Neural stem cells, Retinoic acid 相似文献73.
74.
Slimane Lahsaini Anas Aguelmous Loubna El Fels Leila Idrissi Salah Souabi Mohamed Zamama 《Compost science & utilization》2017,25(2):130-140
The evolution of organic matter of sludge from vegetable oil refining (50%) mixed with turf (40%) and straw (10%) during 6 months of composting was evaluated by physicochemical and spectroscopy analysis. The intense microbial activity is characterized by a significant increase in temperature (over 67°C) during the thermophilic phase (7 days). The final product is characterized by a decomposition rate of 50, C/N ratio about 12, NH4+/NO3? ratio less than 1, and a neutral pH. The lipid analysis showed that total lipids decreased by 83% as a result of biodegradation of lipid compounds of the composted substrate. The degree of polymerization during composting is of about 16%, which provides information on the success of the process. The spectroscopic analysis showed a decrease of the ratios E4/E6 and E2/E6, which clearly shows the humification of organic matter. The physicochemical and spectroscopy parameters of the mixture show the stability and maturity of the final compost, which is confirmed by the germination index (60% for lettuce and turnips, and 90% for cress and lucerna). The results of the evolution of sludge from vegetable oil refining mixed with green wastes produced a mature product that can be applied in agriculture. 相似文献
75.
Mohsen Hamidpour Leila Akbari Hossein Shirani 《Communications in Soil Science and Plant Analysis》2017,48(3):262-273
In this study, we investigated, with pot experiments, whether combined application of zeolites and vermicompost is more effective than single application on plant growth and heavy metals’ uptake in a heavy metal contaminated soil. The results showed that co-application of these amendments decreased zinc (Zn) and cadmium (Cd) availability by their redistribution from plant available forms to organic matter and metal oxide associated fractions. While, the addition of vermicompost and zeolites increased the lead (Pb) concentration significantly in the soluble/exchangeable form as compared with the control. Applying vermicompost individually or in combination with zeolites markedly increased plant biomass. Single zeolites and vermicompost reduced Zn and Pb contents of corn roots and shoots compared to un-treated soil, but less compared to the combined zeolite and vermicompost treatments. The results obtained suggest that co-application of zeolites and vermicompost could be an option for immobilizing Cd, Pb, and Zn in heavy metal contaminated soils. 相似文献
76.
Sayed Zia Mohammadi Tahereh Rohani Leila Bahadori 《Communications in Soil Science and Plant Analysis》2017,48(11):1359-1368
In the present work, magnetic iron oxide nanoparticles (MIONPs) coated with sodium dodecyl sulfate (SDS) and modified with 1-(2-pyridylazo)-2-naphthol (PAN) as a new nanoparticle were prepared and used as an adsorbent for the extraction and preconcentration of copper ions. After adsorption, copper ions were desorbed with nitric acid (HNO3), followed by determination with flame atomic absorption spectrometry (FAAS). The extraction conditions0. were investigated systematically. The linear range 3.0–500.0 ng mL?1 and the detection limit of 0.6 ng mL?1 were obtained. The relative standard deviation (RSD) of the method for seven replicate determinations of 0.1 µg mL?1 of Cu(II) was 2.2%. The method was applied for the determination of Cu(II) in different water samples with good trueness. The accuracy was also evaluated through analyses of a certified reference material (CRM TMDW-500). 相似文献
77.
Leila Shekari Maryam Mozafariyan Mirza Hasanuzzaman Farshad Sadeghi 《Journal of plant nutrition》2017,40(6):761-772
Selenium (Se) is an essential element for humans but is not considered as essential for plants. However, its beneficial role in improving plant growth and stress tolerances is well established. In order to study the role of Se in cadmium (Cd) toxicity in pepper (Capsicum frutescens cv. Suryankhi Cluster), this experiment was carried out in greenhouse conditions. Treatments comprised Cd [0, 0.25, and 0.5 mM cadmium chloride (CdCl2)] and Se [0, 3, and 7 µM sodium selenite (Na2SeO3)] with three replications. The result showed that Cd decreased chlorophyll a, chlorophyll b, and carotenoids, whereas Se supplementation diminished Cd toxicity on photosynthetic pigment. Selenium at 7 µM significantly increased the leaf area in the plants grown at 0.25 mM Cd. The application of Se at 3 µM with 0.25 mM Cd and Se at 3 µM and Se at 7 µM with 0.5 mM Cd increased the activity of catalase (CAT). Selenium at 7 µM decreased the proline content of pepper leaves exposed to Cd at 0.5 mM (30%). Selenium significantly enhanced the antioxidant activity of leaves, which was diminished by Cd toxicity. In general, Se has a beneficial effect on plant growth and is an antioxidant enzyme of pepper cv. Suryankhi Cluster under Cd stress and non-stress conditions. 相似文献
78.
Marziyeh Aghazadeh Mohammad Samiei Vahideh Raeisdasteh Hokmabad Effat Alizadeh Neda Jabbari Alexander Seifalian Roya Salehi 《Fibers and Polymers》2018,19(11):2245-2253
Presently, tissue engineering is employed in the restoration and repair of tissue defects. Degradable scaffolds, stem cells and stimulating factors are employed in this method. In this study, the effect of melanocyte-stimulating hormone (MSH) and/or hydroxyapatite (HA) on proliferation, osteoblast differentiation, and mineralization of human dental pulp stem cells (hDPSCs) seeded on PLLA-PCL nanofibrous scaffolds was evaluated. For this aim, PLLA-PCL-HA nanofibrous scaffolds were fabricated using electrospinning method. FE-SEM images exhibited that all nanofibers had bead-free morphologies with average diameters ranging from 150–205 nm. Human DPSCs seeded into PLLA-PCL nanofibers were treated with MSH. Cell viability, proliferation, morphology, osteogenic potential, and the expression of tissue-specific genes were assessed by means of MTT assay, FE-SEM, alizarin red S staining, and RT-PCR analysis. hDPSCs exhibited improved adhesion and proliferation capacity on the PLLA-PCL-HA nanofibers treated with MSH compared to other groups (p<0.05). Additionally, PLLA-PCL-HA nanofibers treated with MSH exhibited significantly higher mineralization and alkaline phosphatase activity than other groups. RT-PCR results confirmed that PLLA-PCL-HA nanofibers enriched with MSH could significantly unregulated the gene expression of BMP2, osteocalcin, RUNX2 and DSPP that correlated to osteogenic differentiation (p<0.05). Based on results, incorporation of HA nanoparticles in PLLA-PCL nanofibers and addition of MSH in media exhibited synergistic effects on the adhesion, proliferation, and osteogenesis differentiation of hDPSCs, and therefore assumed to be a favorable scaffold for bone tissue engineering applications. 相似文献
79.
Leila Bandian Hosein Nemati Mohammad Moghaddam 《Communications in Soil Science and Plant Analysis》2019,50(1):1-9
Under excessive application of nitrogen fertilizer, vegetables can accumulate high levels of nitrate in their vegetative body and, when consumed by living organisms, pose serious health-related risks for humans. Regarding such problems, it is necessary to minimize the accumulation of nitrate in leafy vegetables. Therefore, a pot experiment was conducted to evaluate bentonite levels (0, 20, 40, 60, 80 g/kg soil) application and urea fertilization times (25, 50, 75 days after sowing; at the rate of 0.2 g per pot) on the growth, development and nitrate accumulation of spinach. Results showed that urea fertilization on 25 days after sowing date had the highest effect on the quality, while application of 60 gr bentonite had the highest effect on the improvement of growth parameters of spinach. The lowest nitrate and nitrite accumulation rate was observed at urea fertilization on 50 days after planting and lack of bentonite application, whereas the lowest oxalic acid content was obtained at urea fertilization on 25 days after planting in a soil without bentonite application. The results showed that implementing an appropriate rate of bentonite and urea fertilization times may bring about favorable results for spinach production. 相似文献
80.
Lauren E. Page Melissa A. Kubai Rachel A. Allbaugh Leila Bedos Mackenzie M. Roy Jonathan P. Mochel Lionel Sebbag 《Veterinary ophthalmology》2023,26(4):331-338