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121.
This study attempts to evaluate the effects of deviation of external nose to nasal airflow patterns. Four typical subjects were chosen for model reconstruction based on computed tomography images of undeviated, S-shaped deviated, C-shaped deviated and slanted deviated noses. To study the hypothetical influence of deviation of external nasal wall on nasal airflow (without internal blockage), the collapsed region along the turbinate was artificially reopened in all the three cases with deviated noses. Computational fluid dynamics simulations were carried out in models of undeviated, original deviated and reopened nasal cavities at both flow rates of 167 and 500 ml/s. The shape of the anterior nasal roof was found to be collapsed on one side of the nasal airways in all the deviated noses. High wall shear stress region was found around the collapsed anterior nasal roof. The nasal resistances in cavities with deviated noses were considerably larger than healthy nasal cavity. Patterns of path-line distribution and wall shear stress distribution were similar between original deviated and reopened models. In conclusion, the deviation of an external nose is associated with the collapse of one anterior nasal roof. The crooked external nose induced a larger nasal resistance compared to the undeviated case, while the internal blockage of the airway along the turbinates further increased it.  相似文献   
122.
目的:探讨中医序贯疗法联合丙酸氟替卡松鼻喷雾剂治疗慢性鼻窦炎的临床疗效。方法:选择2017年8月至2019年2月在我院接受治疗的120例慢性鼻窦炎Ⅱ型患者,采用抽签法分为观察组(n=61)和对照组(n=59)。两组均给予功能性内镜鼻窦手术治疗,对照组给予丙酸氟替卡松鼻喷雾剂治疗,观察组在对照组的基础上给予中医序贯疗法治疗。比较两组患者的临床疗效,治疗前后鼻黏膜纤毛传输速率(MTR)、血清白细胞介素4(IL-4)、白细胞介素6(IL-6)、肿瘤坏死因子(TNF-α)、中医症候积分水平的变化情况及并发症的发生情况。结果:治疗后,两组总有效率分别为96.72%,79.66%,观察组显著高于对照组(P0.05);两组MTR、血清IL-4、IL-8、TNF-α水平均较治疗前显著改善,且观察组MTR高于对照组,血清IL-4、IL-8、TNF-α水平明显低于对照组(P0.05);两组中医症候积分水平均较治疗前显著降低,且观察组中医症候积分水平显著低于对照组(P0.05)。治疗期间,两组并发症总发生率分别为1.64%、15.25%观察组显著低于对照组(P0.05)。结论:中医序贯疗法联合丙酸氟替卡松鼻喷雾剂慢性鼻窦炎患者的临床效果显著优于丙酸氟替卡松鼻喷雾剂治疗,其可更有效改善患者MTR。减轻炎症反应,且安全性更高。  相似文献   
123.
古正强  王文兵  史世奎  邓祥俊  唐秀  郑敏文 《生物磁学》2013,(34):6723-6725,6760
目的:研究在单排CT轴位螺旋扫描联合多层面重组技术重建冠状面影像诊断鼻腔疾病,评价其诊断价值和可行性。方法:对2012年1月-2013年3月我院耳鼻咽喉科进行单排CT轴位螺旋扫描的患者,共219例,对这些患者加做冠状位扫描,比较重建后的影像资料与直接冠状位扫描的图像的分辨率情况,并评估重建质量及运用价值。,结果:单排CT轴位螺旋扫描后冠状面重组的图像:边界清楚、完整,数据无丢失。利用重组技术后重建的结构清晰、连续,能够真实地反映鼻腔、鼻窦及病变结构的实际情况。但分辨率较直接冠状位平扫的患者稍差。结论:单排CT轴位螺旋扫描后冠状面重组的图像,虽然分辨率不如直接冠状位扫描图像高,但与解剖结构、原图像等相结合仍能分辨出病变情况,基本可以满足诊断要求和临床需要。  相似文献   
124.
The nasal pathway represents an alternative route for non-invasive systemic administration of drugs. The main advantages of nasal drug delivery are the rapid onset of action, the avoidance of the first-pass metabolism in the liver and the easy applicability. In vitro cell culture systems offer an opportunity to model biological barriers. Our aim was to develop and characterize an in vitro model based on confluent layers of the human RPMI 2650 cell line. Retinoic acid, hydrocortisone and cyclic adenosine monophosphate, which influence cell attachment, growth and differentiation have been investigated on the barrier formation and function of the nasal epithelial cell layers. Real-time cell microelectronic sensing, a novel label-free technique was used for dynamic monitoring of cell growth and barrier properties of RPMI 2650 cells. Treatments enhanced the formation of adherens and tight intercellular junctions visualized by electron microscopy, the presence and localization of junctional proteins ZO-1 and β-catenin demonstrated by fluorescent immunohistochemistry, and the barrier function of nasal epithelial cell layers. The transepithelial resistance of the RPMI 2650 cell model reached 50 to 200 Ω × cm2, the permeability coefficient for 4.4 kDa FITC-dextran was 9.3 to 17 × 10−6 cm/s, in agreement with values measured on nasal mucosa from in vivo and ex vivo experiments. Based on these results human RPMI 2650 cells seem to be a suitable nasal epithelial model to test different pharmaceutical excipients and various novel formulations, such as nanoparticles for toxicity and permeability.

Electronic supplementary material

The online version of this article (doi:10.1007/s10616-012-9493-7) contains supplementary material, which is available to authorized users.  相似文献   
125.
张银运  刘武 《人类学学报》2010,29(2):150-158
对南京直立人所具有的高耸鼻梁, 本文作者曾从人鼻的功能、鼻梁高耸程度与气候因素的关系以及因纽特人的鼻对寒冷气候的适应等方面进行过论证,认为是对气候适应的结果。本文从南京直立人的生存年代、若干形态项目的可靠性、人类的适应性以及高耸鼻梁的化石人类谱系对这一问题作进一步的论证。结果表明: 1)尚无可靠的证据能够否定南京直立人是生活在距今58—62万年这一年代测定数据。在南京直立人生存时,欧洲远古人类尚未具有像南京直立人那样的高耸鼻梁; 2)人类高耸鼻梁这一适应性特征的形成会有永久性的影响, 是遗传特征, 其后代即使生活在与其祖先不同的气候环境里, 这个特征也不会马上改变; 3)如果有所谓的Bodo高鼻梁的化石人类谱系存在的话, 则南京直立人的高耸鼻梁与欧洲化石人类的基因或与这个Bodo谱系的基因并无遗传上的关系。一个合理的解释是, 南京直立人的高耸鼻梁不可能意味着西方血统。  相似文献   
126.
127.
Background Far less is known about the normal anatomy of the nasal cavity of Eulemur fulvus; no computed tomography (CT) scan has ever been published. Methods Relevant CT scans were taken in the transverse, dorsal and longitudinal planes. These scans were compared with anatomical sections of heads. Results Computed tomography scans revealed almost all nasal structures, but cannot differentiate between the various layers of the nasal mucosa. Results show a double‐scroll arrangement of the ventral nasal concha. The dorsal nasal concha protrudes into the maxillary sinus, but no protrusion into the frontal sinus was observed. The ethmoturbinate I is completely closed back on itself and rostrally voluminous. Conclusions This work shows that at a clinical level, the integrity of the different turbinates can easily be appreciated from a simple CT scan. It will assist clinicians to evaluate pathological conditions that affect the nasal region.  相似文献   
128.
Reactive oxygen species (ROS) released by neutrophils have been suggested to play an important role in cancer development. Since the mechanisms underlying this effect in the respiratory tract are still unclear, we evaluated DNA damage induced by neutrophils in respiratory tract epithelial cells in vitro and in vivo. For in vitro studies, rat lung epithelial cells (RLE) were co-incubated with activated neutrophils, neutrophil-conditioned medium, or hydrogen peroxide. For in vivo studies, we considered the human nose as a target organ, comparing neutrophilic inflammation in the nasal lavage fluid with the oxidative DNA lesion 8-hydroxydeoxyguanosine (8-OHdG) in epithelial cells obtained by nasal brush. Our in vitro data show that human neutrophils are able to induce both 8-OHdG and strand breaks in DNA from RLE cells. Our data also suggest that DNA damage induced by neutrophils is inhibited when neutrophil-derived H2O2 is consumed by myeloperoxidase. In contrast, in the nose no association between neutrophil numbers and 8-OHdG was found. Therefore, it remains unclear whether neutrophils pose a direct genotoxic risk for the respiratory tract epithelium during inflammation, and more in vivo studies are needed to elucidate the possible association between neutrophils and genotoxicity in the lung.  相似文献   
129.
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130.
We investigated whether an intranasal immunization with mutant toxic shock syndrome toxin 1 (TSST-1) could elicit a protective effect against nasal colonization as well as systemic infection of Staphyloccoccus aureus in a mouse model. Anti-TSST-1 antibody production in the mucosal exudates and in sera was efficiently induced. Bacterial numbers were reduced in spleen, liver and also nasal cavities in the early stage of nasal colonization, and the survival rate was significantly improved in the immunized mice. It was suggested that the neutralizing activity of antibodies and the enhanced bactericidal activity of neutrophils were involved in the protection against systemic S. aureus infection, and the secreted antibodies could be involved in reduction of S. aureus bacterial counts in the nasal cavity.  相似文献   
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