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101.
Xiaozhen Lin 《The British journal of oral & maxillofacial surgery》2019,57(8):760-764
The increase in the pharyngeal airway space after mandibular advancement has not been well explained, and in this study we aimed to show whether there is a correlation in the increase of pharyngeal airway space as a consequence of the mandibular advancement or of the relative change between the mandibular position and the natural head position (NHP). Fifteen patients who had bilateral sagittal split osteotomy for mandibular advancement with or without genioplasty were studied retrospectively. The primary variables of mandibular position, NHP, and pharyngeal airway space were measured in three dimensions using preoperative and postoperative cone-beam computed tomographic datasets and were compared using the paired t test. The secondary variable of pharyngeal airway space was defined as the square root of the mean cross-sectional area (CSA1/2) of the pharyngeal airway space. Pearson’s correlation coefficient was used to find out whether there was a correlation between the change in CSA1/2 and the change in mandibular position, or the relative change between the mandibular position and the NHP. Volumes and minimal cross-sectional areas were increased in the pharyngeal airway space, and lengths of airways decreased. Correlation existed only between the increase in CSA1/2 and the relative change between the mandibular position and NHP. The increase in pharyngeal airway space after mandibular advancement correlated with the relative changes between the mandibular position and the NHP. 相似文献
102.
Fatma Çiftci Başak Gülpınar Çetin Atasoy Oya Kayacan Sevgi Saryal 《Advances in medical sciences》2019,64(2):285-291
PurposeCombined pulmonary fibrosis and emphysema (CPFE) has emerged as a new syndrome with characteristics of both fibrosis and emphysema. We determined the impacts of radiologic emphysema severity on pulmonary function tests (PFTs), exercise capacity and mortality.Patients and methodsIPF patients (n = 110) diagnosed at the Chest Diseases Clinic between September 2013 and January 2016 were enrolled in the study and followed up until June 2017. Visual and digital emphysema scores, PFTs, pulmonary artery pressure (sPAP), 6-minute walking test, composite physiologic index (CPI), and survival status were recorded. Patients with emphysema and those with pure IPF were compared.ResultsThe CPFE-group had a significantly greater ratio of men(p < 0.001), lower BMI (p < 0.001), lower mean PaO2 (p = 0.005), higher mean sPAP (p = 0.014), and higher exercise desaturation (p < 0.001). The CPFE group had a significantly higher FVC(L)(p = 0.016), and lower FEV1/FVC ratio (p = 0.002), DLCO, and DLCO/VA ratio(p = 0.03 and p = 0.005, respectively). Lung volumes of the CPFE group had significantly higher VC(p = 0.017), FRC (p < 0.001), RV(p < 0.001), RV/TLC(p < 0.001), and TLC(p < 0.001). There were significant correlations between emphysema scores and FVC (L)(p = 0.01), FEV1/FVC(p = 0.001), DLCO (p = 0.003), VC(p = 0.014), FRC (L)(p < 0.001), RV(p < 0.001), TLC(p < 0.001), and RV/TLC (p < 0.001). Mortality rates were comparable between the two groups. CPI (p = 0.02) and sPAP (p = 0.01) were independent predictors of mortality in patients with CPFE.ConclusionsThe presence and severity of emphysema affects pulmonary function in IPF. Patients with CPFE have reduced diffusion capacity, more severe air trapping, worse muscle weakness, more severe exercise desaturation, and pulmonary hypertension. CPI and pulmonary hypertension are two independent risk factors for mortality in subjects with CPFE. 相似文献
103.
《Archivos de bronconeumología》2020,56(1):9-17
IntroductionSmall airway dysfunction (SAD) caused by smoking contributes to the early onset of airflow limitation (AFL), although its impact on patients’ perception of health is largely unknown. We aimed to evaluate the frequency of SAD in active smokers without AFL, and to compare health-related quality of life (HRQoL) of non-smokers, smokers without SAD, smokers with SAD, and smokers with AFL.MethodsA total of 53 active smokers without AFL, 20 smokers with AFL, and 20 non-smokers completed the SF-36 and EuroQoL questionnaires and performed impulse oscillometry and spirometry. Pulmonary parenchymal attenuation was determined in inspiration and expiration. SAD was determined to exist when resistance at 5 Hz (R5), the difference between R5 and R20, and reactance area (AX) exceeded the upper limit of normal.ResultsIn total, 35.8% of smokers without AFL had SAD. No differences were detected in spirometric parameters or pulmonary attenuation between smokers with or without AFL and non-smokers. However, smokers with SAD had worse scores on HRQoL questionnaires than smokers without SAD or non-smokers, and scores compared to smokers with AFL were intermediate. R5 and X5 were identified as independent determinants of HRQoL in smokers without AFL.ConclusionsSAD is common in smokers without AFL, affecting one third of this population, and independently affecting their perception of health. 相似文献
104.
The COVID crisis led hospitals to reorganize care services and to develop innovative strategies to provide care at a distance. In our health care and education centre for adolescents, which provides both long-term psychiatric care and high school education, inpatients and outpatients were mostly confined at home. In order to ensure continuity of care as well as maintain institutional ties, different communication tools were used. Among them, we particularly relied upon Discord (social network initially designed for gamers) which allowed us to set up an entire virtual ward, maintain individual and group care programmes as well as team meetings. This innovation generated a number of preliminary questions and precautions which guided our decisions regarding the server settings. The outcome of this experiment is globally positive, both quantitatively and qualitatively, even if care at a distance showed its limits. Despite the involvement and creativity of health professionals, the confinement period disrupted and even led to the discontinuation of some care projects. 相似文献
105.
目的 探讨缝隙连接阻断剂奎宁(quinine,QUIN)、甘珀酸(carbenoxolone,CBX)对癫痫大鼠海马涟波(ripple)振荡能量变化的影响。 方法 24只大鼠随机分为模型组、丙戊酸(valproate sodium,VPA)组、QUIN组和CBX组(n =6)。建立氯化锂-匹罗卡品(pilocarpine,PILO)癫痫持续状态(status epilepticus,SE)大鼠模型,VPA组、QUIN组和CBX组在注射PILO前3 d,分别给予VPA(抗癫痫一线药物)200 mg/kg灌胃、QUIN 50 mg/kg腹腔注射、CBX 50 mg/kg腹腔注射。脑电图分析各组大鼠造模前后及推注水合氯醛(止痫)前后海马ripple振荡能量改变。 结果 造模前,正常大鼠海马CA1、CA3、齿状回区均可见ripple振荡表达。与建模前1 d比较,注射PILO后10 min,各组ripple平均能量表达逐渐增强,模型组、VPA组和CBX组在止痫前达到最高峰,QUIN组在PILO注射后60 min达到最高峰(P <0.05)。止痫后,3个干预组ripple平均能量恢复至正常水平;模型组在止痫后1 h ripple平均能量恢复至正常水平;且各组均持续正常水平至SE后3 d。ripple最大能量的变化趋势与平均能量类似。 结论 ripple振荡能量改变可以作为癫痫发作早期预警的定量指标;发作间期ripple振荡能量对癫痫的发作并无提示作用;缝隙连接阻断剂可下调癫痫发作期ripple振荡能量。 相似文献
106.
Andrea Garatti Andrea Daprati Marzia Cottini Claudio F. Russo Margherita Dalla Tomba Giovanni Troise Antonio Salsano Francesco Santini Roberto Scrofani Francesca Nicolò Elisa Mikus Alberto Albertini Luca Di Marco Davide Pacini Marco Picichè Loris Salvador Guglielmo M. Actis Dato Paolo Centofanti Lorenzo Menicanti 《The Annals of thoracic surgery》2021,111(4):1242-1251
107.
《Brain stimulation》2021,14(1):55-65
BackgroundTemporal interference (TI) stimulation of the brain generates amplitude-modulated electric fields oscillating in the kHz range with the goal of non-invasive targeted deep brain stimulation. Yet, the current intensities required in human (sensitivity) to modulate deep brain activity and if superficial brain region are spared (selectivity) at these intensities remains unclear.ObjectiveWe developed an experimentally constrained theory for TI sensitivity to kHz electric field given the attenuation by membrane low-pass filtering property, and for TI selectivity to deep structures given the distribution of modulated and unmodulated electric fields in brain.MethodsThe electric field threshold to modulate carbachol-induced gamma oscillations in rat hippocampal slices was determined for unmodulated 0.05–2 kHz sine waveforms, and 5 Hz amplitude-modulated waveforms with 0.1–2 kHz carrier frequencies. The neuronal effects are replicated with a computational network model to explore the underlying mechanisms, and then coupled to a validated current-flow model of the human head.ResultsAmplitude-modulated electric fields are stronger in deep brain regions, while unmodulated electric fields are maximal at the cortical regions. Both experiment and model confirmed the hypothesis that spatial selectivity of temporal interference stimulation depends on the phasic modulation of neural oscillations only in deep brain regions. Adaptation mechanism (e.g. GABAb) enhanced sensitivity to amplitude modulated waveform in contrast to unmodulated kHz and produced selectivity in modulating gamma oscillation (i.e. Higher gamma modulation in amplitude modulated vs unmodulated kHz stimulation). Selection of carrier frequency strongly affected sensitivity to amplitude modulation stimulation. Amplitude modulated stimulation with 100 Hz carrier frequency required ∼5 V/m (corresponding to ∼13 mA at the scalp surface), whereas, 1 kHz carrier frequency ∼60 V/m (∼160 mA) and 2 kHz carrier frequency ∼80 V/m (∼220 mA) to significantly modulate gamma oscillation. Sensitivity is increased (scalp current required decreased) for theoretical neuronal membranes with faster time constants.ConclusionThe TI sensitivity (current required at the scalp) depends on the neuronal membrane time-constant (e.g. axons) approaching the kHz carrier frequency. TI selectivity is governed by network adaption (e.g. GABAb) that is faster than the amplitude-modulation frequency. Thus, we show neuronal and network oscillations time-constants determine the scalp current required and the selectivity achievable with TI in humans. 相似文献
108.
《Vaccine》2021,39(29):3862-3870
Bacillus anthracis, the causative agent of anthrax, continues to be a prominent biological warfare and bioterrorism threat. Vaccination is likely to remain the most effective and user-friendly public health measure to counter this threat in the foreseeable future. The commercially available AVA BioThrax vaccine has a number of shortcomings where improvement would lead to a more practical and effective vaccine for use in the case of an exposure event. Identification of more effective adjuvants and novel delivery platforms is necessary to improve not only the effectiveness of the anthrax vaccine, but also enhance its shelf stability and ease-of-use. Polyanhydride particles have proven to be an effective platform at adjuvanting the vaccine-associated adaptive immune response as well as enhancing stability of encapsulated antigens. Another class of adjuvants, the STING pathway-targeting cyclic dinucleotides, have proven to be uniquely effective at inducing a beneficial inflammatory response that leads to the rapid induction of high titer antibodies post-vaccination capable of providing protection against bacterial pathogens. In this work, we evaluate the individual contributions of cyclic di-GMP (CDG), polyanhydride nanoparticles, and a combination thereof towards inducing neutralizing antibody (nAb) against the secreted protective antigen (PA) from B. anthracis. Our results show that the combination nanovaccine elicited rapid, high titer, and neutralizing IgG anti-PA antibody following single dose immunization that persisted for at least 108 DPI. 相似文献
109.
110.
《Cancer radiothérapie》2022,26(3):494-501
The technological advancement heralded the arrival of precision radiotherapy (RT), thereby increasing the therapeutic ratio and decreasing the side effects from treatment. Contour of target volumes (TV) and organs at risk (OARs) in RT is a complicated process. In recent years, automatic contouring of TV and OARs has rapidly developed due to the advances in deep learning (DL). This technology has the potential to save time and to reduce intra- or inter-observer variability. In this paper, the authors provide an overview of RT, introduce the concept of DL, summarize the data characteristics of the included literature, summarize the possible challenges for DL in the future, and discuss the possible research directions. 相似文献