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41.
D. Passàli L. Bellussi M. Lauriello D. Passali 《European archives of oto-rhino-laryngology》1995,252(6):348-352
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
42.
A. Muttray L. Klimek M. Faas D. Schäfer W. Mann J. Konietzko 《International archives of occupational and environmental health》1999,72(7):485-488
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
43.
Inflammation markers in nasal lavage, and nasal symptoms in relation to relocation to a newly painted building: a longitudinal study 总被引:1,自引:0,他引:1
Wieslander G Norbäck D Wålinder R Erwall C Venge P 《International archives of occupational and environmental health》1999,72(8):507-515
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
44.
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
45.
46.
A. S. Lopatin 《European archives of oto-rhino-laryngology》1996,253(4-5):309-312
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
47.
E. Y. Liang W. W. M. Lam J. K. S. Woo C. A. van Hasselt C. Metreweli 《European radiology》1996,6(4):553-556
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
48.
R. Okeda 《Acta neuropathologica》1978,43(3):217-220
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
49.
D. Cremaschi C. Rossetti M. T. Draghetti C. Manzoni V. Aliverti 《Pflügers Archiv : European journal of physiology》1991,419(5):425-432
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
50.
目的 :探讨鼻腔局部应用丙酸氟替卡松 (FP)喷雾剂对鼻息肉组织中水通道蛋白 2 (AQP 2 )表达的影响及类固醇激素治疗鼻息肉的作用机制。方法 :将 2 6例慢性鼻窦炎鼻息肉患者分为Ⅱ型组 (3期Ⅱ型 14例 )和Ⅲ型组 (Ⅲ型 12例 ) ;Ⅱ型组又分为FP组 (7例 )和对照组 (7例 ) ,Ⅲ型组亦分为FP组 (6例 )和对照组 (6例 )。Ⅱ型组和Ⅲ型组中的FP组术前应用FP喷雾剂喷鼻 7d ,对照组术前鼻腔不予任何处理。术中取 2 6例患者的鼻息肉组织 ,采用SP免疫组化技术检测鼻息肉组织中AQP 2的表达。结果 :Ⅱ型组和Ⅲ型组中的FP组鼻息肉体积明显缩小 ,鼻息肉组织中AQP 2表达的阳性细胞数和面密度值均明显低于对照组 (均P <0 .0 1)。结论 :在FP作用下鼻息肉水肿减轻、体积缩小 ,可能与AQP 2表达减少有关 ,这为类固醇激素治疗鼻息肉作用机制的阐明提供了新的方向 相似文献