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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   
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AIDS and Behavior - Transactional sex increases HIV risk among adolescent girls and young women (AGYW). Understanding the individual and dyadic nature of transactional sex may provide evidence for...  相似文献   
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目的 探讨集束化干预策略联合闭环管理模式对ICU多重耐药菌感染的防控效果。方法选取2020年1~12月EICU住院患者275例作为对照组,实施常规管理;2021年1~10月EICU住院患者239例作为观察组,在常规管理基础上实施集束化干预策略联合闭环管理。结果实施后,观察组多重耐药菌感染发生率明显低于对照组;患者住院日显著低于对照组,4项护理措施执行率(隔离标识、手卫生、环境消毒、医务人员相关知识知晓)、病原学送检率显著高于对照组(均P<0.05)。结论集束化干预联合信息化闭环管理可有效降低EICU多重耐药菌感染发生率。  相似文献   
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AIM: To investigate the clinical characteristics and genetic features of a Bietti crystalline dystrophy (BCD) proband in a Chinese family. METHODS: A Chinese female diagnosed with BCD complicated by bilateral choroidal neovascularization (CNV) and her parents underwent complete ophthalmic examinations, including fundus autofluorescence (AF), fundus photography (FP), fundus fluorescein angiography (FFA), visual field testing, full-field electroretinography (ERG), optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). The sequencing of the CYP4V2 gene was performed to the whole family. RESULTS: Bilateral tiny glittering crystal-like deposits and differing extent of atrophy of the retinal pigment epithelium (RPE) were found in the posterior pole of her fundus. The diffuse hypo-fluorescence shown on AF images and window defects shown on FFA both indicated the atrophy of the RPE and choriocapillaris. OCT showed the thinning of the RPE and choriocapillaris layer, ellipsoid zone (EZ) band defect and CNV in both eyes. OCTA images proofed bilateral type 2 CNV. The visual field test showed central and paracentral scotoma. ERG showed a slightly decreased b-wave in scotopic ERG. Gene sequencing identified three mutations of the CYP4V2 gene, c.802_807del, c.810delT, and c.1388G>A. The mutation c.1388G>A was a novel substitution mutation. CONCLUSION: The novel mutation c.1388G>A may be a possible cause that could induce the clinical phenotype of BCD.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - To investigate the impact of single-vision spectacle use on myopia progression in children with low myopia. MYOSOTIS is a...  相似文献   
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Background

During coronavirus disease 2019 (COVID-19)–related operating room closures, some multidisciplinary thoracic oncology teams adopted a paradigm of stereotactic ablative radiotherapy (SABR) as a bridge to surgery, an approach called SABR-BRIDGE. This study presents the preliminary surgical and pathological results.

Methods

Eligible participants from four institutions (three in Canada and one in the United States) had early-stage presumed or biopsy-proven lung malignancy that would normally be surgically resected. SABR was delivered using standard institutional guidelines, with surgery >3 months following SABR with standardized pathologic assessment. Pathological complete response (pCR) was defined as absence of viable cancer. Major pathologic response (MPR) was defined as ≤10% viable tissue.

Results

Seventy-two patients underwent SABR. Most common SABR regimens were 34 Gy/1 (29%, n = 21), 48 Gy/3–4 (26%, n = 19), and 50/55 Gy/5 (22%, n = 16). SABR was well-tolerated, with one grade 5 toxicity (death 10 days after SABR with COVID-19) and five grade 2–3 toxicities. Following SABR, 26 patients underwent resection thus far (13 pending surgery). Median time-to-surgery was 4.5 months post-SABR (range, 2–17.5 months). Surgery was reported as being more difficult because of SABR in 38% (n = 10) of cases. Thirteen patients (50%) had pCR and 19 (73%) had MPR. Rates of pCR trended higher in patients operated on at earlier time points (75% if within 3 months, 50% if 3–6 months, and 33% if ≥6 months; p = .069). In the exploratory best-case scenario analysis, pCR rate does not exceed 82%.

Conclusions

The SABR-BRIDGE approach allowed for delivery of treatment during a period of operating room closure and was well-tolerated. Even in the best-case scenario, pCR rate does not exceed 82%.  相似文献   
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