表没食子儿茶素没食子酸酯的抗感染作用研究进展

表没食子儿茶素没食子酸酯（epigallocatechin gallate，EGCG）是茶多酚的主要组成成分。EGCG具有多种生物学功能，包括抗细菌、抗真菌、抗病毒、抗肿瘤、抗炎症、抗衰老、抗肥胖、抗糖尿病、心血管疾病的预防和保护、免疫调节、神经保护等生物学功能。本文主要归纳了EGCG在治疗新型冠状病毒（SARS-CoV-2）感染中的潜在作用，在耐药细菌感染中的预防和治疗作用，以期为EGCG在抗感染药物开发方面提供一定的理论依据。     

PBL教学法在核医学理论教学中的应用研究

目的探讨PBL教学法在核医学理论教学中的应用效果。方法选取我院2019年9月—2020年10月参加核医学课程学习的医学专业的本科学生92名,用随机数字法分为对照组和研究组,每组各46名,对照组应用传统教学法,研究组应用PBL教学法。对两组学习情况(理论知识、阅片能力、临床技能)、教学效果满意度以及自评评价(有无提高自身学习主动性、有无提高自身表达能力、有无提高自身查阅文献的能力、有无增强自身对于影像诊断的分析和思维能力)进行比较。结果研究组学习情况优于对照组,差异有统计学意义(P<0.05)。研究组教学效果满意度高于对照组,差异有统计学意义(P <0.05)。研究组自评评价优于对照组,差异有统计学意义(P <0.05)。结论在核医学理论教学中,应用PBL教学法,有效提高教学效果,加强学生对理论知识的记忆,具有可行性,同时,增强学生的综合素质,并提升临床综合能力,值得在临床上进一步推广应用。     

Electro‐optic probe for real‐time assessments of RF electric field produced in an MRI scanner: Feasibility tests at 3 and 4.7 T

During magnetic resonance imaging (MRI) examinations, the average specific absorption rate (SAR) of the whole body is calculated as an index of global energy deposition in biological tissue without taking into account the presence of metallic implants or conductive materials. However, this global SAR calculation is not sufficient to ensure patient safety and a local SAR measurement should be carried out. Several measurement techniques have already been used to evaluate the local SAR, in particular electric field (E‐field) probes, but the accuracy of the measurements and the resolutions (spatial and temporal) depend strongly on the measurement method/probe. This work presents an MR‐compatible, subcentimeter probe based on an electro‐optic (EO) principle enabling a real‐time measurement of the local E‐field during MRI scans. The experiments using these probes were performed on two different MR systems (preclinical and clinical) having different static magnetic field strengths and with different volume coil geometries. The E‐field was measured with unloaded (in air) and loaded volume coils in order to assess the sensing characteristics of the optical probe. The results show an excellent linearity between the measured E‐field and the radiofrequency (RF) magnetic field in both experimental conditions. Moreover, the distribution of the E‐field throughout the volume coil was experimentally determined and was in good agreement with numerical simulations. Finally, we demonstrate through our measurements that the E‐field depends strongly on the dielectric properties of the medium.     

Research participation effects: a skeleton in the methodological cupboard

ObjectiveThere have been concerns about impacts of various aspects of taking part in research studies for a century. The concerns have not, however, been sufficiently well conceptualized to form traditions of study capable of defining and elaborating the nature of these problems. In this article we present a new way of thinking about a set of issues attracting long-standing attention.Study Design and SettingWe briefly review existing concepts and empirical work on well-known biases in surveys and cohort studies and propose that they are connected.ResultsWe offer the construct of “research participation effects” (RPE) as a vehicle for advancing multi-disciplinary understanding of biases. Empirical studies are needed to identify conditions in which RPE may be sufficiently large to warrant modifications of study design, analytic methods, or interpretation. We consider the value of adopting a more participant-centred view of the research process as a way of thinking about these issues, which may also have benefits in relation to research methodology more broadly.ConclusionResearchers may too readily overlook the extent to which research studies are unusual contexts, and that people may react in unexpected ways to what we invite them to do, introducing a range of biases.     

托幼机构组织-参与健康教育对儿童口腔保健的干预效果评价

目的：探索并推广改善学龄前儿童口腔保健知识和行为习惯的健康教育模式。方法随机选取朝阳区2所幼儿园的451例儿童作为干预组，采用互动式课程系统进行儿童口腔保健的干预；选取另外2所幼儿园的521例儿童作为对照组，不进行特殊的健康教育与行为干预。干预结束后，比较干预组和对照组儿童口腔保健知识和口腔保健行为习惯的改善程度；并调查干预组幼儿园工作人员对互动式课程系统的使用意见。结果干预组儿童口腔保健知识和行为习惯在干预前后比较差异有统计学意义（t＝14．31，P＜0．001），口腔保健知识掌握率由81．79％提高到94．89％，提高幅度大于对照组（t＝5．34，P＜0．001）。结论组织-参与式健康教育模式对提高儿童口腔保健知识掌握率和改善口腔保健行为习惯具有明显效果，可在幼儿园推广应用。     

Selective Mapping of Deep Brain Stimulation Lead Currents Using Acoustoelectric Imaging

We describe a new application of acoustoelectric imaging for non-invasive mapping of the location, magnitude and polarity of current generated by a clinical deep brain stimulation (DBS) device. Ultrasound at 1MHz was focused near the DBS device as short current pulses were injected across different DBS leads. A recording electrode detected the high-frequency acoustoelectric interaction signal. Linear scans of the US beam produced time-varying images of the magnitude and polarity of the induced current, enabling precise localization of the DBS leads within 0.70mm, a detection threshold of 1.75mA at 1 MPa and a sensitivity of 0.52 ± 0.07 μV/(mA*MPa). Monopole and dipole configurations in saline were repeated through a human skullcap. Despite 13.8-dB ultrasound attenuation through bone, acoustoelectric imaging was still >10dB above background with a sensitivity of 0.56 ± 0.10 μV/(mA*MPa). This proof-of-concept study indicates that selective mapping of lead currents through a DBS device may be possible using non-invasive acoustoelectric imaging.     

葛根素注射液联合巴曲酶治疗突发性耳聋的临床疗效观察

目的 研究葛根素注射液联合巴曲酶治疗突发性耳聋的临床效果。方法 选择2016年2月—2016年12月在榆林市星元医院进行诊治的突发性耳聋患者78例，随机分为两组，每组各39例。对照组给予巴曲酶注射液，每次10 BU，加入500 mL生理盐水中稀释后进行静脉滴注，每两天1次。观察组在对照组基础上联合静脉滴注葛根素注射液治疗，将0.4 g葛根素注射液加入250 mL生理盐水中进行静脉滴注，每天1次。两组均治疗10 d。比较两组的临床治疗效果，以及治疗前后的活化部分凝血活酶时间、凝血酶时间、凝血酶原时间和血浆纤维蛋白原，全血黏度低切、血细胞比容、全血黏度高切、血浆黏度和纯音听阈值。结果 观察组的有效率为89.74%，明显高于对照组的71.79%，差异有统计学意义（P<0.05）。两组治疗后的凝血酶时间、活化部分凝血活酶时间以及凝血酶原时间均明显升高，血浆纤维蛋白原明显降低，同组治疗前后比较差异有统计学意义（P<0.05）；且两组间相比差异有统计学意义（P<0.05）。两组治疗后的全血黏度低切、血细胞比容、全血黏度高切及血浆黏度均明显降低，同组治疗前后比较差异有统计学意义（P<0.05）；且观察组明显低于对照组，差异有统计学意义（P<0.05）。两组治疗后的纯音听阈值均明显改善，同组治疗前后比较差异有统计学意义（P<0.05）；且观察组明显优于对照组，差异有统计学意义（P<0.05）。结论 葛根素注射液联合巴曲酶治疗突发性耳聋的临床效果明显优于单独使用巴曲酶，不仅可以有效改善患者的临床症状还可以改善血液流变学状态以及血液高凝状态。     

糖皮质激素治疗突发性耳聋的临床效果观察

目的：研究分析糖皮质激素治疗突发性耳聋的临床效果。方法：选取在我院治疗的突发性耳聋患者80例（2014年5月～2015年5月）。将其动态随机化分2组，研究组和对照组各40例。对照组患者给予非激素常规治疗，研究组患者在常规治疗的基础上给予糖皮质激素进行治疗，对比两组患者突发性耳聋的临床疗效。结果：研究组患者治愈率为27．50％，总有效率为87．50％，与对照组患者对比存在明显差异（P＜0．05）。结论：采用糖皮质激素对突发性耳聋患者进行治疗的效果显著，能有效改善患者听力情况，在临床上可以广泛应用。