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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   
2.
《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   
3.
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   
4.
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   
5.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals.  相似文献   
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通过回顾2014年以来全国各省辐射事故应急演习工作的成果和经验,结合国际原子能机构(IAEA)、生态环境部关于辐射事故应急演习的相关指导文件,总结了综合性辐射事故应急演习的开展流程。此外,基于演习实战化的要求,详细介绍演习规划、准备、实施、评估等环节的技术要求和规范方法,为开展辐射事故应急演习提供参考和借鉴。  相似文献   
9.
《Molecular therapy》2022,30(5):1885-1896
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10.
目的研究门冬胰岛素联合阿托伐他汀对糖尿病肾病患者的疗效及对氧化应激反应的影响。方法选择2018年1月~2019年12月收治的63例糖尿病肾病患者,随机分为两组。对照组单用门冬胰岛素,观察组采用门冬胰岛素联合阿托伐他汀。结果观察组的有效率为93.55%,明显高于对照组的71.87%(P<0.05);治疗后,两组的血清GSH-Px和SOD水平均明显升高(P<0.05),血清MDA水平明显下降(P<0.05),且观察组的变化幅度明显大于对照组(P<0.05);治疗后,两组的血清NO和FMD水平明显升高(P<0.05),血清vWF、3-NT和PAI-1水平明显降低(P<0.05),且观察组的变化幅度明显大于对照组(P<0.05);治疗后,两组的血清TGF-β1和TIMP-1水平明显降低(P<0.05),且观察组的变化幅度明显大于对照组(P<0.05)。结论门冬胰岛素联合阿托伐他汀能提升糖尿病肾病患者机体的抗氧化能力,减轻氧化应激反应和肾脏纤维化程度,保护血管功能。  相似文献   
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