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1.
《Dental materials》2022,38(5):811-823
ObjectivesIn-vivo experimental techniques to understand the biomechanical behavior of a restored tooth, under varying oral conditions, is very limited because of the invasive nature of the study and complex tooth geometry structure. Therefore, 3D-Finite element analyses are used to understand the behavior of a restored tooth under varying oral conditions. In this study, the distribution of maximum principal stress (MaxPS) and the location of MaxPS on a restored tooth using six different commercially available dental resin composites under the influence of thermal and thermomechanical stimuli are performed.MethodsAn intact tooth was scanned using µ-CT and segmented to obtain separate geometric models of the tooth, including enamel and dentine. Then, a class II mesial-occlusal-distal (MOD) cavity was constructed for the tooth model. The restored tooth model was further meshed and imported to the commercial Finite Element (FE) software ANSYS. Thermal hot and cold stimuli at 50 °C and 2 °C, respectively, were applied on the occlusal and lingual surface of the tooth model with the tooth’s ambient temperature set at 37 °C. A uniform loading of 400 N was applied on the occlusal surface of the tooth to imitate the masticatory forces during the cyclic thermal stimuli.ResultsThe results of this study showed that the restorative materials with higher thermal conductivity showed a lower temperature gradient between the restoration and enamel, during the application of thermal stimuli, leading to a higher value of MaxPS on the restoration. Moreover, on applying thermal stimuli, the location of MaxPS at the restoration-enamel junction (REJ) changes based on the value of the coefficient of thermal expansion (CTE). The MaxPS distribution on the application of simultaneous thermal and mechanical stimuli was not only dependent on the elastic modulus of restorative materials but also their thermal properties such as the CTE and thermal conductivity. The weakest part of the restoration was at the REJ, as it experienced the peak stress level during the application of thermomechanical stimuli.SignificanceThe findings from this study suggest that restorative materials with lower values of elastic modulus, lower coefficient of thermal expansion and higher values of thermal conductivity result in lower stresses on the restoration. The outcomes from this study also suggest that the thermal and mechanical properties of a restorative material can have a considerable effect on the selection of restorative materials by dental clinicians over conventional restorative materials. 相似文献
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目的 探索Kolb学习模型在护理实习生人文关怀能力培养中的应用效果。方法 以2019年6月和2020年6月进入昆山市中医医院临床实习的护生作为研究对象,其中2019年实习的护生109名为对照组,2020年实习的护生116名为观察组。观察组采取基于Kolb学习模型的人文关怀临床带教,对照组采取传统方法行人文关怀临床带教。实习结束时分别采用护生人文关怀量表和自主学习能力量表来测评两组护生的学习效果。结果 观察组护生人文关怀能力和自主学习能力各维度得分均高于对照组,差异具有统计学意义(P<0.01,P<0.05)。结论 Kolb学习模型应用于护生人文关怀教学中,可以提高护生人文关怀能力及自主学习能力,提升教学质量。 相似文献
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目的:构建儿科门急诊药房用药指导岗位胜任力标准。方法:运用问卷调研法收集各大儿科医院中患儿照护人需要的用药指导信息,运用文献分析法查阅国内外规范中要求药师提供的用药指导信息,据此设计专家函询问卷。选取全国三甲儿科医院或医院儿科的20名专家,采用Delphi法进行两轮专家函询。结果:问卷回收率为100%,两轮函询后,专家权威系数为0.83。各级指标变异系数均<0.25,专家意见肯德尔和谐系数为0.416~0.836,均满足P<0.05。建立的儿科门急诊药房用药指导岗位胜任力共分为4个层次的指标,其中一级指标3项、二级指标14项、三级指标20项,3项为儿科特色指标、四级指标7项,均为儿科特色指标。结论:本研究构建的儿科门急诊药房用药指导岗位胜任力标准具有权威性和科学性,"分剂量药品储存""儿童用药方法""喂药的技巧与对策"等指标体现了明确的儿科特色,为儿科门急诊药师的用药指导能力培养提供了方向和依据。 相似文献
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《Mayo Clinic proceedings. Mayo Clinic》2022,97(3):560-570
ObjectiveTo assess whether long-term cancer survivors (≥5 years after diagnosis) are at an increased risk of experiencing an opioid-related emergency department (ED) visit or hospitalization compared with persons without cancer.MethodsA 1:1 matched retrospective cohort study was performed using the Surveillance, Epidemiology, and End Results–Medicare linked data sets. The analysis was conducted from October 2020 to December 2020 in persons who lived 5 years or more after a breast, colorectal, lung, or prostate cancer diagnosis matched to noncancer controls on the basis of age, sex, race, pain conditions, and previous opioid use. Fine-Gray regression models were used to assess the relationship between cancer survivorship status and opioid-related ED visit or hospitalization.ResultsThe incidence of opioid-related ED visits and hospitalizations was 51.2 (95% CI, 43.5 to 59.8) and 62.2 (95% CI, 53.4 to 72.1) per 100,000 person-years among cancer survivors and matched noncancer controls, respectively. No significant association was observed between survivorship and opioid-related adverse event among opioid naive (hazard ratio, 0.79; 95% CI, 0.61 to 1.02) and non-naive (hazard ratio, 1.26; 95% CI, 0.84 to 1.89) cohorts.ConclusionCancer survivors and noncancer controls had a similar risk of an ED visit or inpatient admission. Guidelines and policies should promote nonopioid pain management approaches especially to opioid non-naive older adults, a population at high risk for an opioid-related ED visit or hospitalization. 相似文献
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《Clinical lung cancer》2022,23(3):191-194
BackgroundTo accelerate drug approvals while maintaining scientific rigor in the evaluation of a therapeutic's efficacy and safety, the United States Food and Drug Administration now considers real-world data (RWD) to support New Drug Applications and expanded indications. Response Evaluation Criteria in Solid Tumors (RECIST) are the gold standard in clinical trials, but the derivation of RECIST-based treatment response from RWD is unproven. This study investigated the feasibility of implementing RECIST criteria in RWD by comparing lung cancer response assessments from RECIST-based measurement of lesions on archived radiologic films with results from medical oncologist and radiologist narratives recorded in electronic health records (EHR).Materials and MethodsResponse to index treatment via different assessment approaches was compared among 30 metastatic non-small cell lung cancer (mNSCLC) patients receiving systemic treatment (index) after progression on a platinum or anti-PD(L)-1-containing regimen. Specifically, responses based on assessments documented in the medical oncologists’ narratives were compared to a radiologist's assessments of archived images using RECIST v1.1 criteria. Each patient's best overall response was characterized as complete or partial (CR/PR), stable disease (SD), progressive disease (PD), or not evaluable (NE).ResultsSimilar distributions of best overall response and substantial concordance (77%) between medical oncologist-reported and radiologist re-assessed responses were observed. There were no instances of CR/PR to PD or PD to CR/PR discordance.ConclusionsResults suggest that accurate treatment responses, similar to RECIST, may be derived using RWD. Further validation and improvement of real-world response assessment are needed to develop a scalable real-world approach for response assessment. 相似文献
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《Transfusion Clinique et Biologique》2022,29(3):269-272
A delayed haemolytic transfusion reaction (DHTR) encompasses a positive direct antiglobulin test (DAT) developed anytime between 24 hours to 28 days after cessation of transfusion, a positive eluate or a newly identified alloantibody in the plasma or serum along with features of haemolysis in the patient. Routinely, it is expected that with the transfusion of one unit of packed red cells in a patient of average height and weight, the haemoglobin level and hematocrit increase by 1 g/dL and 3% respectively. However, in a patient with DHTR, an inadequate rise of post-transfusion haemoglobin (< 1 g/dL) or rapid fall in haemoglobin back to pre-transfusion levels is observed. Kidd antibodies are particularly known to cause DHTR, maybe alone or in unison with other antibodies. Detection of these alloantibodies is consequential in providing good transfusion support to these patients. These events may be difficult to detect as they may present as varied clinical features or immunological nuisances. In this case series, we have presented three cases of DHTR with special emphasis on their clinical presentations, immunohaematological evaluations, laboratory parameters and the role of proper transfusion support in these patients to avoid further complications. 相似文献
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背景卵巢低反应(POR)患者较差的妊娠结局一直是生殖医学领域难题之一,但目前关于年龄对POR患者辅助生殖技术(ART)治疗后活产率的阈值效应的研究少见。目的分析年龄对POR患者ART治疗后活产率的影响及其阈值效应。方法商丘市第一人民医院妇产科和新疆医科大学第一附属医院生殖助孕中心2014年8月至2018年12月共收治接受常规体外授精/卵胞质内单精子注射-胚胎移植(IVF/ICSI)助孕治疗的女性共19 185例,选取其中诊断为POR者共3 337例为研究对象。所有患者采用控制性促排卵方案,同时采用IVF/ICSI进行胚胎移植并给予黄体支持治疗。分析所有患者活产婴儿情况,年龄对POR患者ART治疗后活产婴儿的影响采用单因素和多因素Logistic回归分析,并建立平滑拟合曲线、进行阈值效应分析。结果3 337例POR患者ART治疗后活产婴儿1 134例,未活产婴儿2 203例,活产率为33.98%(1 134/3 337)。多因素Logistic回归分析结果显示,年龄是POR患者ART治疗后活产婴儿的独立影响因素〔OR=0.920,95%CI(0.902,0.939),P<0.01〕。建立平滑拟合曲线发现,年龄与POR患者ART治疗后活产率呈负相关,但二者之间并非简单的线性关系;阈值效应分析结果显示,POR患者ART治疗后活产率下降的折点为32岁,即年龄≤32岁的POR患者ART治疗后活产率不受年龄影响〔OR=1.000,95%CI(0.998,1.012),P=0.38〕,但年龄>32岁的POR患者ART治疗后活产率随年龄增长而降低〔OR=0.800,95%CI(0.799,0.823),P<0.01〕。结论年龄是POR患者ART治疗后活产婴儿的独立影响因素,年龄>32岁的POR患者ART治疗后活产率随年龄增长而降低。 相似文献