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1.
Tympanic membranes (TM) that have healed spontaneously after perforation present abnormalities in their structural and mechanical properties; i.e., they are thickened and abnormally dense. These changes result in a deterioration of middle ear (ME) sound transmission, which is clinically presented as a conductive hearing loss (CHL). To fully understand the ME sound transmission under TM pathological conditions, we created a gerbil model with a controlled 50% pars tensa perforation, which was left to heal spontaneously for up to 4 weeks (TM perforations had fully sealed after 2 weeks). After the recovery period, the ME sound transmission, both in the forward and reverse directions, was directly measured with two-tone stimulation. Measurements were performed at the input, the ossicular chain, and output of the ME system, i.e., at the TM, umbo, and scala vestibuli (SV) next to the stapes. We found that variations in ME transmission in forward and reverse directions were not symmetric. In the forward direction, the ME pressure gain decreased in a frequency-dependent manner, with smaller loss (within 10 dB) at low frequencies and more dramatic loss at high frequency regions. The loss pattern was mainly from the less efficient acoustical to mechanical coupling between the TM and umbo, with little changes along the ossicular chain. In the reverse direction, the variations in these ears are relatively smaller. Our results provide detailed functional observations that explain CHL seen in clinical patients with abnormal TM, e.g., caused by otitis media, that have healed spontaneously after perforation or post-tympanoplasty, especially at high frequencies. In addition, our data demonstrate that changes in distortion product otoacoustic emissions (DPOAEs) result from altered ME transmission in both the forward and reverse direction by a reduction of the effective stimulus levels and less efficient transfer of DPs from the ME into the ear canal. This confirms that DPOAEs can be used to assess both the health of the cochlea and the middle ear.  相似文献   
2.
Background and objectiveMinimally invasive surgery of benign middle ear tumours is possible by using the endoscope. The optimal lighting and the broadest vision it offers, allow a transcanal approach to these rare tumours. The objective of this work is to summarize its key points through a case series.Materials and methodsRetrospective study of benign middle ear tumours that underwent exclusive endoscopic surgery in a third-level adult university hospital between June 2018 and June 2020. Postoperative follow-up was performed by otoendoscopy and audiometry.ResultsSix patients underwent surgery during the study period. Five patients were female and one male, with an average age of 57.8 years (± 21.9). Four tumours were in the left ear and 2 in the right ear. These included 4 tympanic paragangliomas (3 type I and one type II), a chorda tympani neuroma, and a congenital cholesteatoma. There were no serious postoperative complications. At present, no tumour recurrence has been found in either case, with a minimum follow-up of 7 months.ConclusionsThe present study adds evidence on the safety and efficacy of endoscopic transcanal ear surgery, as a minimally invasive technique, for the treatment of benign middle ear tumours confined to the tympanic cavity.  相似文献   
3.
Human auditory ossicles, the malleus, the incus, and the stapes, are located in the tympanic cavity in the temporal bone and through forming a chain for the sound transmission from the tympanic membrane to the cochlea, they play an important role in the hearing process. Despite their clinical, phylogenetic, and evolutionary significance, the morphometry of the human ear bones has not been examined systematically. The ear ossicles are the smallest bones of the human skeleton, attaining their final size and morphology already at birth. Initially, they have been found to exhibit minimal morphometric variation, but further studies brought the opposite results. The aim of this study was to examine the morphometric variation of human auditory ossicles recovered from medieval and postmedieval subadult skeletons from Poland, Central Europe. The analysis involved in a total of 166 ear bones. Their measurements were performed on microscopic images using CorelDraw x4, according to a protocol of Quam and Rak with modification of Flohr et al. and Wadhwa et al. Our study showed a significant metric variation in the measurements taken at areas of the greatest morphological variability of the ossicles. We found that greater linear dimensions were associated with lower values of angular measurements. These results reveal the inherent variation found in these supposed functionally constrained structures. Representation of even greater number of populations, time periods, and developmental stages are needed. Further study will expand our understanding of the global scope of variation found in ear ossicular morphology and its functional implications for paleoanthropology.  相似文献   
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目的:探讨脊柱微创经皮椎间孔镜日间手术全程化管理模式的构建与效果。方法:选取2017年3月1日~2018年3月31日行经皮椎间孔镜下髓核摘除术的94例腰椎间盘突出症患者作为对照组,采取常规住院管理模式。选取2018年4月1日~2019年4月30日行经皮椎间孔镜下髓核摘除术日间手术的88例腰椎间盘突出症患者作为日间组,实施涵盖门诊、病房、出院后随访的全程化日间手术管理模式。比较两组临床效果。结果:两组患者术后各期视觉模拟评分法(VAS)、JOA、ODI评分较术前改善(P<0.05),两组术后各期VAS、JOA、ODI评分及并发症发生率比较差异无统计学意义(P>0.05)。日间组术前等待时间、住院时间、直接医疗费用低于对照组(P<0.01),患者满意度高于对照组(P<0.05)。结论:经皮椎间孔镜日间手术全程化管理模式应用于腰椎间盘突出症患者临床疗效较好,具有可行性、安全性、有效性,同时在提高医疗资源的利用率、降低住院费用方面具有明显优势。  相似文献   
6.
 目的 调查医院感染预防与控制课程设计中医学生的教育需求及教师的课程设计建议。方法 采用问卷调查全国5个地区10所医学院校师生的医院感染预防与控制教育需求和课程设计意见,参考塔巴目标模式课程设计步骤,论证课程设计方案。结果 584名学生中,仅11.8%(69名)的学生认为当前医院感染预防与控制教育能完全满足其需求,需求得分居前四位的为手卫生、消毒灭菌隔离、医院感染概论和职业防护。352名教师中,72.7%(256名)建议设必修课;86.4%(304名)选择总学时8~24学时,12.5%(44名)选择24学时以上,被调查教师建议10个章节学时平均总和为19.5;需重点掌握13项、熟悉9项知识和技能;86.4%(304名)教师建议理论与见习学时比为1 ∶0.5及以上;53.4%(188名)教师建议采取理论大课+小组见习(含技能操作)+线上学习的形式;63.7%(224名)教师建议师资团队由医院感染管理科+感染病科+护理部教师共同组成。结论 当前医学生的医院感染预防与控制教育远未完全满足需求,单独开课很有必要,建议设置16~24学时必修课,理论联系实践,多学科师资实施多元化教学,按照必修课考核。  相似文献   
7.
线上一流课程作为一种新型的教学课堂模式,其建设与推广不仅使教师的教和学生的学呈现多元化,而且也使教师的教学和研究水平、学生的学习兴趣和能力得到了有效提升。本团队建设与推广的国家级首批线上一流课程免疫学基础与病原生物学已经完成6个学期的运行,累计学习人数40 395人,累计选课学校84所。本文从建设背景与建设目标、整体框架与建设资源、实施过程与推广应用、教学运行与互动、教学考核与评价、思考和展望等6个方面总结该课程的建设与推广情况。  相似文献   
8.
目的 探讨问题导向式学习(PBL)教学法在中学生艾滋病健康教育的应用效果,为拓展青少年艾滋病健康教育提供科学性参考。方法 随机选取本地区某中学初一年级2个班102名中学生,分别设置对照组与干预组,对照组采用传统课堂讲授法,干预组采用PBL教学法。干预前后采用同一问卷进行调查。结果 干预后,对照组仅在“艾滋病全称”等6项知识(χ2=6.029~9.434,P=0.004~0.028)的知晓率与“应将艾滋病病人进行隔离(χ2=17.275,P<0.001)”、“应对艾滋病病人关心同情(χ2=5.696,P=0.017)”2个条目的态度正向率较干预前有所提高;干预组在各项知识知晓率与态度正向率较干预前均有所提高(χ2=3.840~23.520,P均<0.001~0.05)。干预前,两组在知识知晓率及态度正向率方面的差异无统计学意义(P均>0.05);干预后,干预组在“艾滋病的全称”等9项知识的知晓率均高于对照组(χ2=4.943~10.183,P=0.026~0.001),仅在“对艾滋病病人具有恐惧感”的态度正向率高于对照组(χ2=11.330,P=0.001)。结论 中学生艾滋病健康教育中,PBL教学法具有更好的教学效果,可以在传统课堂教授法的基础上结合运用。  相似文献   
9.
This is an evaluation of neonatal nurses continued professional development delivered in Vietnam. Course outcomes of participant's academic and clinical performance, nurse feedback and service improvement were mapped to Kirkpatrick's evaluation model. The data showed that the nurses were proficient in technical skills but possessed limited autonomous clinical decision-making ability. The training enhanced their understanding of the evidence base underpinning neonatal care, but their learning experience was restricted by limited academic resources available in Vietnamese. The results of the evaluation concluded that in order to support nurses in constructing their own practice knowledge, the training provided should be founded on their individualised and specific clinical and contextual needs rather than replicating existing programmes. Recommendations for nurse continued professional development consists of building capacity amongst the local nursing workforce to ensure sustainability of learning and enhance clinical outcomes.  相似文献   
10.
胎儿大脑中动脉(MCA)血流频谱反映了其心血管对缺氧或血流再分布的早期适应,其测量要求标准化、规范化,是近年来胎儿血流动力学临床应用研究的热点之一。国内外近期出现了一些大样本的回顾性及前瞻性临床研究,对MCA评估指标、参考值范围以及临床各疾病中运用的截断值进行了报道。文章结合2021年版国际妇产科超声学会(ISUOG)胎儿多普勒血流频谱监测指南,对胎儿MCA血流频谱相关的高质量研究进行分析总结,为其临床规范化运用提供参考。  相似文献   
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