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81.
Traditional teaching methods used in medical education couldn't meet the need for keeping pace with up to date information. Present study has conducted in order to compare the effect of lecture and e-learning methods on nursing students' learning outcomes in the context of Iran. A cross-over design was applied. Study sample was consisted of 32 students which were in third semester of nursing bachelor program and were passing Maternal Child nursing course. The first part of the course was taught using lecture method during first four weeks; an e-learning method was the technique used to educate the remained part of the course during the second four weeks. Students' learning outcomes in each method, opinion toward and participation with both educational methods was assessed. No significant difference was found between students exam scores in both methods. Considering students' opinion toward educational methods, no significant difference was found between two methods in general but students reported better "capability" and "independency" in e-learning method while lecture was obtained higher scores in "effectiveness on learning" and "motivation" characteristics. E-learning can be used in teaching some nursing courses. It is recommended to use e-learning method with appropriate interactive strategies and attractive virtual environments to motivate students.  相似文献   
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Hydrogel nanoparticles in drug delivery   总被引:5,自引:0,他引:5  
Hydrogel nanoparticles have gained considerable attention in recent years as one of the most promising nanoparticulate drug delivery systems owing to their unique potentials via combining the characteristics of a hydrogel system (e.g., hydrophilicity and extremely high water content) with a nanoparticle (e.g., very small size). Several polymeric hydrogel nanoparticulate systems have been prepared and characterized in recent years, based on both natural and synthetic polymers, each with its own advantages and drawbacks. Among the natural polymers, chitosan and alginate have been studied extensively for preparation of hydrogel nanoparticles and from synthetic group, hydrogel nanoparticles based on poly (vinyl alcohol), poly (ethylene oxide), poly (ethyleneimine), poly (vinyl pyrrolidone), and poly-N-isopropylacrylamide have been reported with different characteristics and features with respect to drug delivery. Regardless of the type of polymer used, the release mechanism of the loaded agent from hydrogel nanoparticles is complex, while resulting from three main vectors, i.e., drug diffusion, hydrogel matrix swelling, and chemical reactivity of the drug/matrix. Several crosslinking methods have been used in the way to form the hydrogel matix structures, which can be classified in two major groups of chemically- and physically-induced crosslinking.  相似文献   
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Objective Statins are potent inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase and widely used to treat hyperlipidaemia. Apart from their direct lipid-lowering effects, statins may also influence lipid metabolism through modulation of low-density lipoprotein (LDL) receptors. Basophils and mast cells have been reported to express LDL receptors and have been implicated in atherogenesis. The aim of this study was to investigate the effects of statins on the interactions of 125I-LDL with purified primary human blood basophils, a human basophil cell line, KU812, and a human mast cell line, HMC-1.Methods Direct binding experiments were carried out with the primary basophils and KU812 as well as HMC-1 cells before and after pretreatment of the cells with atorvastatin, simvastatin, or cerivastatin. The effects of these three statins on the LDL-uptake and degradation as well as on thymidine incorporation in the cells were also studied.Results Primary basophils, HMC-1 and KU812 cells expressed two classes of LDL binding sites. Exposure to atorvastatin, simvastatin or cerivastatin increased significantly (P<0.05) the number of 125I-LDL binding sites on primary basophils and HMC-1 as well as KU812 cells. The effects of the statins were dose dependent. The statins also enhanced the uptake and degradation of LDL in primary basophils, HMC-1 and KU812 cells. The increase in the number of LDL binding sites induced by statins was abolished by mevalonic acid (200 mol/l). Statins had no effect on the thymidine incorporation into the cells in an unstimulated condition.Conclusion Our results provide evidence for the upregulation of LDL binding sites on human basophils and mast cells by statins. We hypothesise that effects of statins on the lipid metabolism might also involve basophils and mast cells.  相似文献   
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Background  

The potential problems associated with the use of formalin in histology, such as health hazards, degradation of RNA and cross-linking of proteins are well recognized. We describe the utilization of a formalin-free fixation and processing system for tissue detection of two important biopredictors in breast cancer – estrogen receptor and HER2 – at the RNA and protein levels.  相似文献   
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Clinical and Experimental Medicine - The SARS-CoV-2 virus has spread to all corners of the world. Thrombosis is the cause of organ failure and subsequent death in COVID-19. The pathophysiology of...  相似文献   
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Kernicterus is a neurological syndrome associated with indirect bilirubin accumulation and damages to the basal ganglia, cerebellum and brain stem nuclei particularly the cochlear nucleus. To mimic haemolysis in a rat model such that it was similar to what is observed in a preterm human, we injected phenylhydrazine in 7-day-old rats to induce haemolysis and then infused sulfisoxazole into the same rats at day 9 to block bilirubin binding sites in the albumin. We have investigated the effectiveness of human adiposity-derived stem cells as a therapeutic paradigm for perinatal neuronal repair in a kernicterus animal model. The level of total bilirubin, indirect bilirubin, brain bilirubin and brain iron was significantly increased in the modelling group. There was a significant decreased in all severity levels of the auditory brainstem response test in the two modelling group. Akinesia, bradykinesia and slip were significantly declined in the experience group. Apoptosis in basal ganglia and cerebellum were significantly decreased in the stem cell-treated group in comparison to the vehicle group. All severity levels of the auditory brainstem response tests were significantly decreased in 2-month-old rats. Transplantation results in the substantial alleviation of walking impairment, apoptosis and auditory dysfunction. This study provides important information for the development of therapeutic strategies using human adiposity-derived stem cells in prenatal brain damage to reduce potential sensori motor deficit.  相似文献   
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