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1.
宫颈癌是目前唯一病因明确、可以早期预防和治疗并有望根治的癌症,高危型人乳头瘤病毒(HPV)的持续感染是导致宫颈癌发生的必要因素。研究表明,WHO先后认可HPV 12个月持续感染、6个月持续感染可作为新HPV疫苗注册临床试验设计的替代终点,这一替代终点属于经过验证的替代终点,可直接用于新HPV疫苗临床试验。本文论证了我国应用这一替代终点加速新HPV疫苗研发上市的限制因素,并提出相应监管建议。  相似文献   
2.
BackgroundVisually induced dizziness can develop as a sequala of a vestibular disorder and is characterized by symptoms of nausea, dizziness, and imbalance in rich visual environments such as supermarkets and shopping malls. To date the mechanisms underlying visually induced dizziness are poorly understood.Research questionWhat are the characteristics of visual fixations and postural sway in adults with visually induced dizziness compared to healthy adults when exposed to increasingly complex visual environments?MethodsWe recruited 20 adults with visually induced dizziness and 20 healthy adults to this cross-sectional exploratory study. Participants were instructed to maintain gaze on letters projected on a large screen with backgrounds of differing visual complexity. The number of visual refixations, movement of the centre of pressure, and movement of the head and body centres of mass were recorded.ResultsAdults with visually induced dizziness showed a significantly higher number of visual refixations (F= 10.592, p < 0.01), and increased mean velocity of head and body centres of mass movement (F= 14.034, p < 0.01 and F= 6.553, p < 0.05 respectively) compared to healthy adults.SignificanceAdults with visually induced dizziness exhibited visual fixational instability and increased postural and head sway compared to healthy adults. This was mainly observed in conditions with complex and moving backgrounds. This may account for reports from adults with visually induced dizziness of worsening symptoms in busy environments. The results from the study may assist in guiding intervention development to reduce symptoms of visually induced dizziness.  相似文献   
3.
AIM: To investigate the ocular development of patients who had unilateral congenital cataract (CC) combined with persistent fetal vasculature (PFV). METHODS: This cross-sectional, observational study included patients who had unilateral CC and PFV and those with isolated unilateral CC. Axial length (AL), keratometry, anterior chamber depth (ACD), lens thickness, and vitreous length were obtained. The ocular biometric parameters of the affected eyes of patients with CC and PFV were compared with the fellow eyes and with the affected eyes of patients with isolated CC. RESULTS: A total of 110 patients were included and divided into 4 groups: group 1 (18 patients with CC and PFV, <24mo), group 2 (22 patients with CC and PFV, ≥24mo), group 3 (35 patients with CC, <24mo), and group 4 (35 patients with CC, ≥24mo). The ALs of the affected eyes were shorter than those of the fellow eyes in group 1 (20.02±1.06 vs 20.66±0.63 mm, P=0.025). While the ALs of the affected eyes were longer than those of the fellow eyes in group 2 (23.18±2.00 vs 22.31±1.06 mm, P=0.044) and group 4 (22.64±1.80 vs 22.02±1.01 mm, P=0.033). The keratometries of the affected eyes were steeper than those of the fellow eyes in group 2 (44.78±1.66 vs 43.83±1.38 D, P=0.041) and group 4 (43.76±1.91 vs 43.34±1.46 D, P=0.043). No difference of ACDs between two eyes was found in all groups (all P>0.05). CONCLUSION: Compared with the fellow eyes, the ALs of the eyes with unilateral CC and PFV are shorter in patients younger than 24mo and longer in those older than 24mo; the keratometries of the eyes with unilateral CC and PFV are steeper in patients older than 24mo and similar with those younger than 24mo. These findings provide further understanding of ocular development in patients with both CC and PFV.  相似文献   
4.
5.
 目的 探讨持续性次氯酸灌注对内镜终末漂洗水的消毒效果。方法 基线采集内镜终末漂洗水的水样,进行微生物培养和宏基因组二代测序鉴定。引入微酸性次氯酸水发生机后,在安装后的特定时间收集水样进行培养和宏基因组二代测序分析。结果 安装前共采集水样27份,其中10份合格,合格率为37.03%。不合格水样可检出放线根瘤菌、嗜麦芽窄食单胞菌、黄色微杆菌、贪铜菌、藤泽甲基杆菌、少动鞘氨醇单胞菌等水源性细菌;安装后共采集水样54份,均为合格。宏基因组二代测序分析显示,安装前的样本中可检测出大量皮氏罗尔斯顿菌、耐金属贪铜菌、奥斯陆莫拉菌、日本慢生根瘤菌、水生甲基杆菌、戈登分枝杆菌、新鞘氨醇杆菌等细菌序列,消毒后主要为宏基因测序分析常见的背景细菌。结论 持续性次氯酸灌注消毒可有效清除水管路中的细菌,并降低水管路中生物膜的形成,提升内镜终末漂洗水的质量。  相似文献   
6.

Background

Weaning from mechanical ventilation and tracheostomy after prolonged intensive care consume enormous resources with optimal management not currently well described. Restoration of respiratory flow via the upper airway is essential and early cuff-deflation using a one-way valve (OWV) is recommended. However, extended OWV use may cause dry airways and thickened secretions which challenge the weaning process. High-flow therapy via the tracheostomy tube (HFT-T) humidifies inspired air and may be connected via an in-line OWV (HFT-T-OWV) alleviating these problems. We aim to provide clinical and experimental data on the safety of HFT-T-OWV along with a practical guide to facilitate clinical use during weaning from mechanical ventilation and tracheostomy.

Methods

Data on adverse events of HFT-T-OWV were retrieved from a quality register for patients treated at an intensive care rehabilitation center between 2019 and 2022. Benchtop experiments were performed to measure maximum pressures and pressure support generated by HFT-T-OWV at 25–60 L/min flow using two different HFT-T adapters (interfaces). In simulated airway obstruction using a standard OWV (not in-line) maximum pressures were measured with oxygen delivered via the side port at 1–3 L/min.

Results

Of 128 tracheostomized patients who underwent weaning attempts, 124 were treated with HFT-T-OWV. The therapy was well tolerated, and no adverse events related to the practice were detected. The main reason for not using HFT-T-OWV was partial upper airway obstruction using a OWV. Benchtop experiments demonstrated HFT-T-OWV maximum pressures <4 cmH2O and pressure support 0–0.6 cmH2O. In contrast, 1–3 L/min supplemental oxygen via a standard OWV caused pressures between 84 and 148 cmH2O during simulated airway obstruction.

Conclusions

Current study clinical data and benchtop experiments indicate that HFT-T-OWV was well tolerated and appeared safe. Pressure support was low, but humidification may enable extended use of a OWV without dry airway mucosa and thickened secretions. Results suggest the treatment could offer advantages to standard OWV use, with or without supplementary oxygen, as well as to HFT-T without a OWV, for weaning from mechanical ventilation and tracheostomy. However, for definitive treatment recommendations, randomized clinical trials are needed.  相似文献   
7.
目的 研究特发性水平半规管良性阵发性位置性眩晕(HSC-BPPV)复位次数、前庭冷热试验、复位后残余眩晕是否与复发率存在关系。方法 2016年1月—2018年1月门诊手法复位成功的84例特发性HSC-BPPV的患者纳入本研究,所有患者均行Barbecue滚转手法复位。根据复位次数分为A组(<3次)和B组(≥3次);根据患者复位后有无残余眩晕,分为C组(无残余眩晕)和D组(残余眩晕),观察复发率。所有患者均行前庭冷热试验检查。结果 本研究显示A组(20.9%)与B组(26.8%)的复发率无明显差异;C组(11.8%)与D组(32.0%)复发率差异具有统计学意义(P=0.033);复位后存在残余眩晕患者前庭功能异常率高;复位后存在残余眩晕并伴有前庭冷热试验异常的患者复发率最高(66.7%);复发率最低的为复位次数<3次且复位后无残余眩晕的患者(6.3%)。结论 HSC-BPPV复发率与复位次数无关,冷热试验异常与残存眩晕相关,复位后残余眩晕伴前庭冷热试验异常提示患者复发率增高。  相似文献   
8.
目的 探讨特发性良性阵发性位置性眩晕(benign paroxysmal positional vertigo,BPPV)成功复位后出现残余头晕的患者感觉门控P50特点。方法 选择2018年6月至2019年11月就诊于大连市第三人民医院符合入组条件的确诊为BPPV并成功行手法复位后的患者60例,根据治疗7天后有无残余头晕(residual dizziness,RD)分为RD组和无RD组,行感觉门控电位P50检测,记录S1-P50及S2-P50的潜伏期、波幅及S2-P50/S1-P50波幅比值,进行统计学分析。结果 与无RD组相比,RD组S1-P50波幅减低,潜伏期延长,S2-P50波幅增高,潜伏期延长(P<0.05);RD组S2/S1比值高于无RD组,差异具有统计学意义(P<0.05)。结论 感觉门控P50可以客观评价BPPV成功复位后残余头晕患者感觉门控功能缺损情况,提示患者可能存在情绪障碍,为临床治疗提供方向。  相似文献   
9.
瞑眩反应是疾病趋愈的一种祛邪反应,古今医家对其发生机制的观点不一。文章收集、整理瞑眩反应相关文献,总结古、今对瞑眩反应成因的看法,介绍吕文良教授从引阳入阴论瞑眩的经验,以期为临床对其进一步探索提供参考。吕文良教授认为久病之体,宿邪内伏,湿热痰瘀交阻而脏腑经络不通,致卫阳独行于外,不得入阴,机体阴阳失交,而瞑眩反应是机体借助药物作用,引阳入阴,使阴阳复交、正气渐盛,疾病自去而成的一种佳兆。  相似文献   
10.
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