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1.
《The Knee》2021
BackgroundAs knee osteotomy surgery becomes increasingly accessible, more patients may turn to the Internet for information. This study examined the source, quality, content and readability of online information regarding osteotomy around the knee.MethodsThe first 70 websites returned by the top four search engines were identified using the key words: “knee osteotomy” and “high tibial osteotomy.” The websites were categorised by type and assessed using the DISCERN score, Journal of the American Medical Association (JAMA) benchmark criteria and a novel Knee Osteotomy-Specific Score (KOSS). The presence of the Health On the Net (HON) code accreditation seal was noted. Readability of each website was assessed using eight readability formulae. The mean reading grade level (RGL) was compared to the 6th and 8th grade reading levels. The mean RGL of each category was also compared.ResultsOf the 45 unique websites analysed, the majority were Physician (33%) and Journal websites (31%). The mean DISCERN score was 36.7 (±8.9) which is classified as ‘poor.’ The mean JAMA benchmark criteria score was 2.04 (±1.5) and Physician websites were most likely to be scored zero. The mean KOSS was 15.4 (±5.7). The highest scoring website was a Commercial site but, overall, Journal category sites provided the best quality information. Websites that bore the HONcode seal obtained higher DISCERN, JAMA benchmark criteria and Knee Osteotomy - Specific Scores.The cumulative mean RGL was 13.2 (±2.2) which exceeded the 6th grade level by an average of 7.2 grade levels and the 8th grade level by an average of 5.2 grade levels. No website (0%) was written at or below either the 6th or the 8th grade reading levels. The mean Flesch Reading Ease Score of all websites was 41.13 (±14.7) which is classified as ‘difficult.’ Journal websites had the highest RGL.ConclusionThe information available online regarding osteotomy around the knee varies tremendously in quality and completeness. Physician sites predominate, but these were among the lowest scoring of all websites. Even where high quality information is available, it is set at too high a level to be easily understood.Level of evidenceSurvey of materials – Internet. 相似文献
2.
静电纺丝技术在生物医用材料领域中的应用 总被引:2,自引:0,他引:2
电纺丝是一种使带电荷的聚合物溶液或熔体在静电场中射流来制备聚合物超细纤维的加工方法。由于电纺丝技术制得的纤维,其直径可达纳米级,因此电纺丝纤维应用广泛。对静电纺丝技术的一些重要特性和当前在生物医用材料领域中的应用进行综述。 相似文献
3.
目的:建立测定植物油料(油菜籽、花生、黄豆、玉米、芝麻)中胆固醇含量的超高液相-串联四极杆质谱(UPLC-MS/MS)方法。方法:样品经皂化后用石油醚-乙醚(1∶1)提取,以2,2,3,4,4,6-d6胆固醇为内标,Waters ACQUITYUPLCBEH C18(2.1 mm×50 mm,1.7μm)色谱柱为分析柱,含0.1%甲酸的甲醇溶液为流动相,大气压化学电离源(APCI)正离子模式,多反应检测方式测定。胆固醇和内标离子检测对m/z分别为369.2→146.9,369.2→160.9和375.2→166.5。结果:胆固醇在0.05μg.ml-1~10μg.ml-1范围内线性关系良好(r=0.999),最小检出量为0.1 ng,方法回收率为106%。结论:本方法具有良好的灵敏度、准确度及专属性,可用于植物油料中胆固醇含量测定。 相似文献
4.
加强高校化学实验物品管理的探讨 总被引:1,自引:0,他引:1
化学实验物品数量众多,品种繁杂,主要包括材料、低值品和易耗品等三大类。作为高校物资管理人员应增强信息观念、市场观念,不断加强理论和实践的学习,全面提高自身素质,搞好物资管理工作。同时,高校物资管理部门应完善物资管理制度,加强科学管理,为教学、科研工作提供有力保障和优质服务,为高校的发展做出应有的贡献。 相似文献
5.
Effect of Paraffin and Silica Matrix Phase Change Materials on Properties of Portland Cement Mortars
Vicente Zetola Luis J. Claros-Marfil Alfonso García Santos Fco. Javier Neila Gonzlez 《Materials》2021,14(4)
In the search for methods to incorporate Phase Change Materials (PCM) into Portland cement mortar mixtures, PCM based on paraffins adhered to a silica-based matrix appear as a suitable option. However, paraffin particles have been observed to escape from the silica matrix when water is added. There are only limited data on how the use of such PCM affects the behaviour of mortars. To evaluate the effect of this PCM addition, Portland mortar mixtures were elaborated with 5%, 10% and 15% of PCM content, and using CEM 42.5 I R and CEM I 52.5 R cement types. Physical properties such as density, open porosity, air content and water absorption were analysed for fresh and dry samples. The results obtained show that the PCM-added mixtures require greater water and cement amounts than the standard mortar mixtures to achieve similar compressive strengths. Compared to non-PCM mixtures the PCM-added mortars present a density lowering of 37% for fresh mixtures and near 45% for dry state forms. A maximum compressive strength of 15.9 MPa was reached for 15% PCM mixtures, while values beyond 40 MPa were achieved for 5% PCM mixtures. Thus, the proposed study contributes to broad the available knowledge of PCM cement mortar mixtures behaviour and their mix design. 相似文献
6.
Evaggelia Papia Ryo Jimbo Bruno R. Chrcanovic Martin Andersson Per Vult von Steyern 《Dental materials》2014
Objectives
The objectives of the study were to describe the surface structure and the chemical surface composition of Y-TZP ceramics produced by using the modified additive technique and to evaluate the flexural strength of Y-TZP with or without surface modification and with different pretreatments: etching before or after sintering combined with or without an adhesive cement system.Methods
Y-TZP discs were used for surface analysis (n = 48) and for biaxial flexural strength testing (n = 200). The specimens were divided into groups depending on the cementation surface of Y-TZP: unmodified, sandblasted or glass-modified Y-TZP surfaces, and according to the production process: etching before or after sintering.Results
The surface structure and the chemical composition of glass-modified Y-TZP differ; a rougher surface and phase transformation was identified compared to unmodified Y-TZP.The unmodified Y-TZP groups showed significantly higher flexural strength compared to the glass-modified groups (p < 0.001) and showed increased flexural strength after sandblasting (p < 0.001). Furthermore, by adding cement to the surface, the value increased even further in comparison with the sandblasted non-cemented specimens (p < 0.01). After thermocycling, however, the cement layer on the unmodified and the sandblasted surfaces had air pockets and regions with loose cement.Significance
A rougher surface structure, superficial glass remnants and a higher content of m-phase was present in the cementation surface of glass-modified Y-TZP. The glass modification creates a bondable cementation surface that is durable. By etching the glass-modified Y-TZP before sintering, a more homogenous surface is created compared to one that is etched after sintering. 相似文献7.
Marina Angélica MARCIANO Roberto Brand?o GARCIA Bruno Cavalini CAVENAGO Paloma Gagliardi MINOTTI Raquel Zanin MIDENA Bruno Martini GUIMAR?ES Ronald ORDINOLA-ZAPATA Marco Antonio Hungaro DUARTE 《Journal of applied oral science : revista FOB》2014,22(4):268-273
Objectives
To investigate if there is a relation between the increase of bismuth oxide and the decrease of pH levels and an intensification of toxicity in the Portland cement.Material and Methods
White Portland cement (WPC) was mixed with 0, 15, 20, 30 and 50% bismuth oxide, in weight. For the pH level test, polyethylene tubes were filled with the cements and immersed in Milli-Q water for 15, 30 and 60 days. After each period, the increase of the pH level was assessed. For the biocompatibility, two polyethylene tubes filled with the cements were implanted in ninety albino rats (n=6). The analysis of the intensity of the inflammatory infiltrate was performed after 15, 30 and 60 days. The statistical analysis was performed using the Kruskal-Wallis, Dunn and Friedman tests for the pH level and the Kruskal-Wallis and Dunn tests for the biological analysis (p<0.05).Results
The results showed an increase of the pH level after 15 days, followed by a slight increase after 30 days and a decrease after 60 days. There were no significant statistical differences among the groups (p>0.05). For the inflammatory infiltrates, no significant statistical differences were found among the groups in each period (p>0.05). The 15% WPC showed a significant decrease of the inflammatory infiltrate from 15 to 30 and 60 days (p<0.05).Conclusions
The addition of bismuth oxide into Portland cement did not affect the pH level and the biological response. The concentration of 15% of bismuth oxide resulted in significant reduction in inflammatory response in comparison with the other concentrations evaluated. 相似文献8.
宋代官药局作为国家开设经营的大型药品销售机构,在其经营过程中取得了一定的经济和社会效益.官药局每年会有大量的药材、药品支出,为满足官药局经营的药材需求,宋政府每年需要收集购买大量药材.官药局药材来源可分为宋王朝的内部来源和外部来源,前者包括每年地方上交官方的土贡、官方自营的药园及官方出资采购等渠道;后者主要是其他政权的... 相似文献
9.
[目的]探讨不同材料的烤瓷熔附金属全冠(PFM)修复后对患者牙周组织、龈沟液中炎症因子水平的影响.[方法]选取本院2013年1月至2015年6月接受牙修复的患者60例,根据修复材料分为:镍铬合金烤瓷冠修复(A组)、镍铬合金镀金烤瓷冠修复(B组)、金沉积烤瓷冠修复(C组)各20例,测定三组患者修复前、修复后6个月的龈沟液量(GCF)、龈沟探诊深度(GCD)、牙龈指数(GI)、龈沟液中肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、白细胞介素-8(IL-8)的水平.[结果]修复前,A组、B组和C组患者的GCF、GCD、GI指数差异均无统计学意义(P>0.05);修复6个月后复查,A组患者的GCF、GCD、GI指数较修复前显著升高(P<0.05),A组患者的GCF、GCD、GI指数显著高于B组和C组患者(P<0.05);修复前,A组、B组和C组患者龈沟液中TNF-α、IL-1β、IL-6、IL-8的水平差异均无统计学意义(P>0.05);修复6个月后复查,A组患者的TNF-α、IL-1β、IL-8的水平较修复前显著升高(P<0.05),A组患者的TNF-α、IL-1β、IL-8水平显著高于B组和C组患者(P<0.05).[结论]镍铬合金烤瓷冠对患者的牙周组织影响更为明显,患者牙龈沟液中炎症反应因子水平更高. 相似文献
10.
不同材料根管充填后近期疼痛发生情况分析 总被引:16,自引:0,他引:16
目的比较活髓牙经不同材料根管充填后的疼痛发生情况。方法288颗需要进行根管治疗的活髓牙分为4组,2组分别采用Cortisomol糊剂+牙胶尖和Vitapex糊剂+牙胶尖一次性根管充填;2组经引流24~48h后,分别用Cortisomol糊剂+牙胶尖和Vitapex+牙胶尖根管充填;观察术后1周内的疼痛发生情况。结果所有患牙中,根充后可自愈性疼痛的发生率为22.6%,非自愈性疼痛的发生率为2.08%;一次性根充组中,Cortisomol糊剂组较Vitapex糊剂组的可自愈性疼痛发生率低,有显著性差异(P<0.01);引流后根充组中,Cortisomol糊剂组较Vitapex糊剂组的可自愈性疼痛发生率低,但无显著性差异(P>0.05);各组间非自愈性疼痛的发生率均无显著性差异(P>0.05);大多数患牙根充后的疼痛发生在72h之内。结论Cortisomol糊剂+牙胶尖根管充填可以减少根充后疼痛的发生。 相似文献