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61.
Schwannomas are neurogenic neoplasms rarely found in the sinonasal tract, where localization to the nasal septum is exceedingly rare (only 11 cases have been described in the western literature). We report the case of a 29-year-old white male with a schwannoma completely filling the left nasal fossa and arising from the bony part of the septum. A computer tomography (CT) scan and a biopsy suggestive of benign schwannoma were obtained before the lesion was removed by a degloving approach. The preoperative diagnosis of nasal septum schwannoma was confirmed. The patient is asymptomatic and without endoscopic evidence of recurrence 7 years after surgery. A review of the literature with particular emphasis on the clinical presentation, histological features, differential diagnosis and therapeutic options for such a rare lesion is included. Received: 11 June 1999 / Accepted: 10 February 2000  相似文献   
62.
In this paper we have analyzed the physical properties of nasal mucus from 120 outpatients with rhinitis. We focused on the most relevant rheological features: viscosity, elasticity, adhesiveness, as well as ability to be spun (spinability) or poured (pourability). A double-capillary type viscometer was used to measure viscosity and elasticity and the platinum ring method to measure adhesiveness. Spinability was measured with an automatic apparatus (Filancemetre Sefam) and pourability was determined by describing flow under gravity. Efficacy of nasal clearance was analyzed by measuring mucociliary transport time with an inert tracer using vegetal charcoal powder. Results showed that impaired nasal mucosal function in patients with rhinitis could be determined by studying rheological features in addition to measuring mucociliary activity. Information provided proved invaluable when considering possible treatment with agents affecting kinesis of nasal mucus.  相似文献   
63.
Objectives: Irritating effects of organic solvents have usually been measured by means of questionnaires. The aim of the present study was to evaluate the sensitivity of different methods of detecting subclinical irritating effects. Methods: Twelve healthy, non-smoking students were exposed to 200 ppm and to 20 ppm 1,1,1-trichloroethane in an exposure chamber, using a crossover design. The amounts of interleukins (IL)-1β, IL-6 and IL-8 and prostaglandin E2 (PGE2) in nasal secretions were measured. Mucociliary transport time was determined with the saccharine test. Ciliary beat frequency of nasal epithelial cells was measured with video-interference contrast microscopy. Subjective symptoms were assessed by questionnaire. Results: Concentrations of ILs were significantly elevated after exposure to 200 ppm 1,1,1-trichloroethane (IL-1β 82.4 vs. 28.8 pg/ml (medians), P=0.003; IL-6 12.2 vs. 7.2 pg/ml, P=0.01; IL-8 549 vs. 424 pg/ml, P=0.007), whereas the other parameters remained unchanged. Conclusion: The interleukins measured proved to be sensitive indicators of irritating effects of 1,1,1-trichloroethane. The German threshold limit (MAK value) of 200 ppm 1,1,1-trichloroethane does not prevent the subclinical inflammation of nasal mucosa. Received: 3 March 1999 / Accepted: 14 June 1999  相似文献   
64.
Introduction: There is a need to evaluate possible health effects of ventilation improvements and emissions from new buildings, in longitudinal studies. New methods to study biological effects on the eyes and upper airways are now available. Material and methods: A longitudinal study was performed on 83 trained social workers in two offices in Uppsala, Sweden. The exposed group (n= 57) moved to a newly redecorated building nearby. Low emitting building material had been used, including a new type of solvent-free water-based paint. The control group (n= 26) worked in the same office during the study period (November 1995 to February 1996). Hygiene management was carried out in both offices, at the beginning and the end of the investigation. Tear film stability (BUT) was measured. Nasal patency was measured by acoustic rhinometry, and eosinophilic cationic protein (ECP), myeloperoxidase (MPO), lysozyme and albumin were analyzed in nasal lavage fluid (NAL). Results: The relocation resulted in an increase in the personal outdoor airflow rate from 11 to 22 l/s. Indoor concentrations of terpenes were higher in the new building, and powdering of the new linoleum floor was observed. Measurements showed low levels of volatile organic compounds (VOC), formaldehyde, carbon dioxide (CO2), nitrogen dioxide, respirable dust, and microorganisms in the air of all buildings. The move resulted in an increased nasal patency and an increase of ECP and lysozyme in NAL, after adjusting for changes in the control group. No changes were observed for nasal or ocular symptoms. A seasonal effect, with a decrease of ECP, was observed in the control group. Conclusion: A well-ventilated office building can be redecorated without any major ocular or nasal effects, or measurable increase of indoor air pollution if low-emitting building materials are selected. In agreement with previous evidence, the improved ventilation flow may explain the increase of nasal patency. The increase of ECP and lysozyme in NAL suggested an inflammatory effect in the new building. Since this building had increased ventilation flow, increased concentrations of terpenes, and powdering from the polish on the new linoleum floor, identification of causative agents was difficult. The hygiene measures did not give any evidence that emissions from the new type of solvent-free water-based paints or building dampness were responsible for the observed nasal effects. Considering the higher emissions of VOC reported from older types of water-based latex paints and solvent-based wall paints, the new type of solvent-free water-based paint seems to be a good choice from the hygiene point of view. Received: 21 December 1998 / Accepted: 20 June 1999  相似文献   
65.
Wood dust is an irritant and is carcinogenic to the nasal mucosa. It inhibits its own clearance from the nose. It therefore makes sense to lavage retained wood dust from the nose following exposure. To our knowledge this is the second study conducted to determine whether the procedure of nasal lavage reduces nasal symptoms in woodworkers. Forty-six woodworkers from 150 approached volunteered to trial nasal lavage using gravity fed, home-made unbuffered isotonic saline for 2 months in a crossover trial and then be followed-up a year later. The group reported significantly decreased nasal symptoms and over half continued to use nasal lavage voluntarily after 1 year. Results support the findings of the previous study that nasal lavage improves nasal symptoms and supplements those findings with data indicating patterns of voluntary usage following the study's conclusion. It is concluded that nasal lavage is an acceptable, effective and inexpensive option with minimal side effects for woodworkers who experience nasal symptoms and who wish to try the procedure.  相似文献   
66.
避免鼻内窥镜手术并发症的临床解剖   总被引:1,自引:0,他引:1  
目的:为避免鼻内窥镜手术并发症提供解剖学基础。方法:在30侧成人头部正中矢状剖面标本上,观察了泪囊的毗邻、在鼻腔外侧壁上的投影及筛窦的毗邻。结果:泪囊与中鼻道前房相邻,其在鼻腔外侧壁上投影的前界为“骨梭”,后界为钩突基部,上界为中鼻甲附着处前部的下缘,下界为下鼻甲附着处前部的上缘。筛顶壁为一前窄后宽的骨板,筛前、后动脉在筛窦内均靠筛顶下方并与筛板同水平走行。结论:鼻内窥镜手术者若熟悉手术区的解剖可减少或避免并发症。  相似文献   
67.
Biomechanical techniques can be used for correcting C-shaped or S-shaped nasal septum cartilage deformities. These include mucoperichondrium elevation on the concave side, trimming cartilage to its necessary size, incisions to release cartilaginous bends and strip resections. Resection and reimplantation of cartilage are preferable when correcting a difficult post-traumatic septum. While biomechanical principles are applicable to nasal septum surgery, further clinical studies must be devised to provide proper correction of the nasal septum with minimal sacrifice of cartilage.  相似文献   
68.
In order to study the features of sinonasal polyposis (SNP) on CT, 100 consecutive coronasal sinus CT examinations done for chronic inflamamtory sinonasal disease were reviewed. The CT findings of the 27 fully documented SNPs were analyzed. All our SNPs were bilateral. There was a strong tendency for extensive involvement. Nasal polyps were seen in 22 of 27 (81%); bony trabecular deossification in 23 of 27 (85%); widening of infundibulum in 26 of 27(96%). We discovered a new sign truncation of the bony middle turbinate, where the bulbous part of bony middle turbinate was missing, in 51 of 26 (58 %) of SNP patients without a previous history of middle turbinectomy, 12 of 15(80%) were bilateral. The one SNP patient (1 of 27) with previous middle turbinectomy was not regarded to be real truncation. Truncation of the bony middle turbinate is a characteristic and easily recognizable ancillary sign, and is not seen in other patterns of sinusitis. Together with other features on coronal sinus CT, this adds diagnostic confidence in diagnosing sinonasal polyposis. Correspondence to: E. Y. Liang  相似文献   
69.
Summary Two cases of extracranial heterotopia of the brain are reported. Case 1, in an otherwise normal female baby, had a brain heterotopia in the submandibular region. Case 2, in a still-born female baby with anencephaly, had the heterotopia in the lung. The lesion in case 1 is believed to be an encephalocele that has been pinched off through a cleft in the bone or through a foramen of the skull; the pathogenesis is similar to that of the so-called nasal glioma. Concerning the pathogenesis of case 2, contrary to the generally supported embolism theory, observation of serial sections of the tumor in the lung favors the aspiration theory according to which amniotic brain tissue fragments, which are dislocated into the amnion because of nonclosure of the ventricle or following destruction of the fetal brain, are aspirated by fetal respiratory movements in the 4th to 6th month of intrauterine life.  相似文献   
70.
Transepithelial pathways of macromolecule transport have been studied in vitro in rabbit nasal respiratory mucosa, maintained at 27° C. Transepithelial electrical potential difference, short-circuit current and resistance were 3.4±0.5mV (submucosa positive), 65.0±6.7 A cm–2 and 52.1±5.6 cm–2 respectively (n=15). These electrical characteristics are those of a leaky epithelium allowing macromolecules to permeate paracellularly. A detailed permeation study of a polypeptide (elcatonin, M w=3362) was also undertaken. Elcatonin mucosa-submucosa (J ms) and submucosa-mucosa (J sm) fluxes were measured by radioimmunoassay. With 10 g/ml elcatonin, J ms was significantly larger than J sm for the whole 120-min period of observation; net flux showed a maximum in the first 30 min (J ms=13.6±1.0 ng cm–2 h–1, J sm=1.4±0.1 ng cm–2 h–1, n=10). J ms fell towards the value of J sm if the temperature was reduced to 4°C or if the mucosa was simultaneously treated with 0.1 mM dinitrophenol and 3 mM monoiodoacetate. J ms and J net followed saturation kinetics with increasing elcatonin concentrations. Adrenocorticotropic hormone (M r=4500) produced a similar pattern to elcatonin. However, J ms and J sm were not significantly different from each other at any time either for [3H]sucrose (M w=342) or for [14C]polyethyleneglycol-4000 (M w=4000) when present in the bathing medium at 500 M concentration. The results show active transport of polypeptides in parallel with passive permeation (possibly through leaky intercellular junctions). Active transport does not appear to be related to nonspecific pinocytosis but to receptor-mediated endocytosis. The latter may be important for the sampling of potential antigens from the nasal lumen.  相似文献   
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