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The Interactive Whiteboard (IWB) is now a common technological artefact in Swedish preschools and schools. This study examines preschool teachers’ thinking behind the embedding of IWB in the early years’ mathematics classroom and how preschool teachers structure their mathematical activities when using IWB. Two complementary empirical studies, that is, interviews and video observations, were conducted with four preschool teachers. The findings demonstrate that (just) having a positive attitude to technological artefacts like IWB is less likely to enrich the learning environment and lead to pedagogical change. This suggests that teachers’ IWB use is mostly informed by their pedagogical knowledge.  相似文献   
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IntroductionEndothelin-1 (ET-1) is the most potent among all vasoconstrictors, and its association with cardiovascular diseases has been reported before. Our aim was to investigate the association of ET-1 plasma level and its gene polymorphisms (rs5370 and rs10478694) with hypertension and coronary atherosclerosis (CA).Material and methodsThis study was carried out on 128 women and 132 men, who were divided into 4 groups: hypertensive without atherosclerosis (H+A–); hypertensive with atherosclerosis (H+A+); non-hypertensive with atherosclerosis (H–A+); and non-hypertensive without atherosclerosis (control group). Endothelin-1 plasma levels were measured by ELISA, and gene polymorphisms were detected by polymerase chain reaction – restriction fragment length polymorphism (PCR-RFLP) methods. Coronary artery diseases (CAD) were then defined based on angiography data.ResultsThe ET-1 plasma level was significantly higher in the H+A+ group in comparison with the other groups, especially H+A–. Comparing people with CA and those without it, the highest frequency level of the T allele of rs5370 was found in people with CA. Significantly higher frequencies of the 3A allele were detected in hypertensive patients in comparison with non-hypertensive individuals, when analyzing rs10478694.ConclusionsEndothelin-1 plasma level shows a direct association with the risk of CA development. The T allele of rs5370 can be regarded as a risk factor for CA development. The 3A allele of rs10478694 can be associated with the risk of hypertension; therefore, it can be concluded that ET-1 and its gene polymorphisms play an important role in CA development and hypertension observed in the south-eastern populations of Iran.  相似文献   
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The present article describes the resin infiltration technique to address white spots lesions presented on anterior and premolar teeth of a young patient after orthodontic treatment and the digital workflow for planning a diastema closure on the maxillary anterior teeth using facial photographs, an intraoral scanner, a facially driven diagnostic waxing using a dental computer‐aided design (CAD) software, and 3‐piece additive manufactured (AM) clear silicone indices. The virtual design of the silicone indices was completed using an open‐source CAD software and included a flexible clear buccal piece, flexible clear lingual piece, and rigid clear custom tray. The unique 3‐piece index design allows a horizontal path of insertion, controlled uniform thickness of the indices, flexible and rigid material properties combination, accurate translation of the diagnostic waxing into the patient´s mouth, and digital storage of the designs.  相似文献   
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Fumonisin B1 is a common secondary metabolite produced by Fusarium moniliforme that occurs in corn and corn-based foods. This mycotoxin is toxic to many species of laboratory and domestic animals and is known to induce a variety of diseases such as hepatic cancer and renal and hepatic dysfunction. The structure of fumonisin B1 (FB1) resembles sphingolipids so it can inhibit synthesis of ceramide, an enzyme in the sphingolipid biosynthetic pathway. This inhibition leads to the disruption of sphingolipid metabolism and increased levels of sphinganine and sphingosine (sphingoid bases) in the serum of treated animals. It is believed that the toxicity effect of fumonisin B1 is the result of these sphingoid bases. In the present research, mice were treated with FB1 to determine its pathological effects on gastric gland and gastric mucosa in the treated mice. For this purpose, the mice were randomly assigned into two groups, namely, control (n?=?14) and treatment (n?=?15). The treatment group was fed with prepared food containing FB1 (150 mg/kg) for a period of 4 months. One day after the last treatment, all animals in both groups were euthanized and their stomach were sampled and prepared for microscopic analysis. Histopathological analysis revealed a significant decrease in parietal cell number and a significant increase in the number of inflammatory cells in gastric mucosa. Also, atrophy of gastric glands was observed. The study confirmed that FB1 poisoning can have toxicopathological effects such as gastric gland atrophy and gastritis on mice gastric tissue.  相似文献   
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IntroductionAdministration of the adjuvant influenza vaccine has been suspected to increase the risk of allograft rejection; however, not much is known about the effect of adjuvant H1N1 vaccination on allograft kidney function. The aim of this study was to evaluate the effect of adjuvant H1N1 vaccine on allograft kidney function.MethodsA total of 78 stable kidney transplant recipients were enrolled in the study. These patients were vaccinated with a pandemic adjuvant H1N1 inactivated intramuscular influenza vaccine. Local and systemic adverse reactions occurring for 2 weeks after vaccination were recorded. Serum creatinine, creatinine clearance, and 24-hour urine proteinuria were measured before and 1 and 3 months and 2.5 years after vaccination.ResultsMean patient age was 45 ± 14 years (range, 21–78 years). Serum creatinine, creatinine clearance, and 24-hour urine proteinuria levels were not significantly different between before and 1 month after vaccination (1.3 ± 0.35 vs 1.3 ± 0.5 mg/dL, 83 ± 28 vs 78 ± 31 mL/min, and 356 ± 437 vs 293 ± 307 mg, respectively). Serum creatinine level did not differ significantly between before and 2.5 years after vaccination (1.3 ± 0.35 vs 1.4 ± 0.39 mg/dL; P > .05). No rejection episodes occurred during 2.5 years of follow-up. Reported adverse reaction frequencies included pain (20%), muscle aches (4%), fever (2.6%), and headache (1.3%).ConclusionsThe use of pandemic adjuvant H1N1 influenza vaccination is safe in patients after kidney transplantation. However, larger cohort studies with longer follow-up periods are needed to confirm this issue.  相似文献   
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Aim: Urinary stone disease affects people of all ages. With its satisfactory efficacy ranges in all age groups and lack of side‐effects, extracorporeal shock wave lithotripsy (ESWL) has become the preferred treatment modality for uncomplicated renal and proximal calculi ≤20 mm. In the present study, we aimed to assess the safety and efficacy of the ESWL treatment in elderly patients. Methods: A retrospective study was carried out on patients aged over 65 years who underwent shock wave lithotripsy at our Department from 2009 to 2011, with a Siemens Lithostar electromagnetic shockwave lithotripter. A total of 231 patients (157 males, 74 females) out of 1694 (13.6%) were studied. The patients were divided into two groups (group 1 = 65–70; group 2 >70). The effect of age and other possible predicting factors (sex, stone localization and stone size) were investigated. Concomitant diseases and related complications were also evaluated. Results: An overall stone‐free rate (SFR) of 82.2% was found. The influence of sex on SFR was non‐significant. There was no significant difference when comparing SFR between the age groups. When patients were divided into those with renal and ureteral stones, the SFR were 94.4% and 67.6% (P < 0.01), respectively. The SFR of the stone size groups, ≤10 mm and >10 mm were 80% and 84.4%, respectively. Comorbidity was present in 148 patients. Complications were noted in 56 of 231 patients. Of 56 patients, 43 had minor complications and 13 major complications. Conclusion: ESWL seems to be an effective first‐line treatment choice for urinary stones in elderly patients with careful patient selection and personalized preparation. Geriatr Gerontol Int 2012; 12: 413–417.  相似文献   
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Tissue engineered heart valves (TEHVs) that can grow and remodel have the potential to serve as permanent replacements of the current non-viable prosthetic valves particularly for pediatric patients. A major challenge in designing functional TEHVs is to mimic both structural and anisotropic mechanical characteristics of the native valve leaflets. To establish a more biomimetic model of TEHV, we fabricated tri-layered scaffolds by combining electrospinning and microfabrication techniques. These constructs were fabricated by assembling microfabricated poly(glycerol sebacate) (PGS) and fibrous PGS/poly(caprolactone) (PCL) electrospun sheets to develop elastic scaffolds with tunable anisotropic mechanical properties similar to the mechanical characteristics of the native heart valves. The engineered scaffolds supported the growth of valvular interstitial cells (VICs) and mesenchymal stem cells (MSCs) within the 3D structure and promoted the deposition of heart valve extracellular matrix (ECM). MSCs were also organized and aligned along the anisotropic axes of the engineered tri-layered scaffolds. In addition, the fabricated constructs opened and closed properly in an ex vivo model of porcine heart valve leaflet tissue replacement. The engineered tri-layered scaffolds have the potential for successful translation towards TEHV replacements.  相似文献   
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