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71.
J. MULLOL E. LÓPEZ J. ROCA-FERRER A. XAUBET L. PUJOLS J. C. FERNÀNDEZ-MORATA J. M. FABRA† C. PICADO 《Clinical and experimental allergy》1997,27(12):1432-1441
Background Eosinophil infiltration is a hallmark of the inflammatory response in rhinitis and in nasal polypcsis. Objective We studied the effect of steroids and nedocromil sodium on eosinophil survival primed by epithelial cells from healthy (nasal mucosa) and inflamed (nasal polyp) respiratory tissue. Methods Blood eosinophils were incubated with increasing concentrations (10-11 10-5 M) of topical steroids (fiuticasone propionate, budesonide, triamcinolone acetonide and beclomethasone dipropionate) and/or nedocromil sodium prior to the addition of human epithelial cell conditioned media (HECM), eosinophil viability was measured and IC50 for each drug was calculated. Results All four steroids and nedocromil sodium caused a dose-related inhibition of HECM-induced eosinophil survival. The IC50 of steroids were lower in eosinophils primed by mucosa HECM than on those primed by polyp HECM (fluticasone, 4nM vs 114nM: budesonide, 21 nM vs 280 nM; triamcinolone, 7 nM vs 853 nM; and beclomethasone, 171 nM vs 181 nM). The combined inhibitory effect of 10-7M budesonide plus 10-5M nedocromil (43.8 ± 10.8%, P < 0.03) was significantly higher than budesonide (28.5 ± 9.2%) or nedocromil (16.7 ± 5.4%) alone and close to 10-5M budesonide (52.3 ± 11%). No differences were found in cytokine (IL-8, IL-6, GM-CSF, TNFα, IL-lβ and RANTES) concentrations between HECM from mucosa and polyps. Conclusion These results suggest that topical anti-inflammatory drugs may diminish airway eosinophilic infiltration by decreasing eosinophil viability, that nasal polyp epithelial cell secretions may induce steroid resistance in eosinophils, and that nedocromil sodium has additive effects with steroids. 相似文献
72.
M. HASEGAWA 《Clinical otolaryngology》1994,19(2):135-137
Nasal resistance is affected by posture. In this study, the effects of supine and lateral recumbent positions were investigated in eight normal subjects and 31 patients with allergic rhinitis. Of the 31 patients with allergic rhinitis, five showed unilateral complete nasal obstruction and one patient showed bilateral complete obstruction during the change of posture. Total nasal resistance had a tendency to increase with repeating the change of posture (a paired t-test, P < 0.05). The supine and lateral recumbent positions did not induce variable changes in total nasal resistance in normal subjects. Posture induces complete nasal obstruction in the supine or lateral recumbent positions in some patients with allergic rhinitis. 相似文献
73.
烹调油烟对机体健康的危害 总被引:17,自引:0,他引:17
烹调油烟气含有200多种有害气体。实验研究和流行病学调查表明:油烟气可损伤肺部功能,引起机体免疫功能下降,并具有致突变性和致癌性,是肿瘤发生的可疑因素。 相似文献
74.
天津市煎炸油卫生状况评价 总被引:2,自引:0,他引:2
通过连续8小时的煎炸实验和对市,郊29个煎炸点的现场卫生学调查及采用羰基值(COV),极性组分(PC)对所采样品的分析表明,天津煎炸油的总体的卫生质量基本符合国家卫生标准,参考极性组分的ADI值并依据本次调查结果,估计天津大部分居民的煎炸食品摄入量安全水平,但对于偏爱煎炸食品者其安全系数明显下降。 相似文献
75.
Ellen A. Eisen Paige E. Tolbert Marilyn F. Hallock Richard R. Monson Thomas J. Smith Susan R. Woskie 《American journal of industrial medicine》1994,26(2):185-202
A case-control study of larynx cancer was conducted within a cohort of automobile workers exposed to metal working fluids, commonly referred to as machining fluids (MF). Results are based on 108 cases of larynx cancer and 5:1 matched controls. Risks associated with specific types of MF, as well as specific components of the fluids were evaluated. Based on a retrospective exposure assessment, lifetime exposures to straight and soluble fluids, grinding particulate, biocides, selected metals, sulfur, and chlorine were examined. Exposure to asbestos and acid mists at two of the three study sites was also characterized. Results suggest that straight mineral oils are associated with almost a two-fold excess in larynx cancer risk. There was also evidence of an association with elemental sulfur, commonly added to straight MF to improve the integrity of the materials under extreme pressure and heat. It is not clear whether sulfur is causally related to an excess relative risk of larynx cancer or whether the observed association is the result of unmeasured confounding by another contaminant or process feature. For example, the high stress operations that require MF enriched with sulfur are also more likely to produce polycyclic aromatic hydrocarbons (PAHs) during the process. Thus, the observed association with sulfur may be due to an association with PAH. The finding of excess risk of laryngeal cancer associated with MF is consistent with several previous reports in the literature. This is the first study, however, to distinguish straight mineral oils from other types of MF. Based on these findings, a general reduction in concentrations of straight mineral oil particulate in occupational environments would be prudent. 相似文献
76.
Bente E. Moen Bjrg E. Hollund Morten Berntsen Ragnar Flo Knut Rasmus Kyvik Trond Riise 《American journal of industrial medicine》1995,27(4):555-564
Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated. 相似文献
77.
Mapping of α- and β-globin genes on Antarctic fish chromosomes by fluorescence in-situ hybridization
Eva Pisano Ennio Cocca Federico Mazzei Laura Ghigliotti Guido di Prisco H. William Detrich III Catherine Ozouf-Costaz 《Chromosome research》2003,11(6):633-640
The pathways and mechanisms of genomic change that have led to the peculiar haemoglobinless phenotype of the white-blooded
Antarctic icefishes (16 species in the family Channichthyidae) constitute an important model for understanding the rapid diversification
of the Antarctic notothenioid fish flock. To provide complementary structural information on genomic change at globin-gene
loci in Antarctic fish species, cytogenetic studies and in-situ chromosomal mapping have been undertaken. Using a DNA probe containing one α- and one β-globin gene from the embryonic/juvenile
globin gene cluster of the red-blooded species Notothenia coriiceps, we mapped the cluster on the chromosomes of Antarctic teleosts by fluorescence in-situ hybridization. As anticipated on the basis of its molecular organization, the cluster was located on a single chromosome
pair in all of the red-blooded fish species probed (N. coriiceps, N. angustata, Trematomus hansoni, T. pennellii). In contrast, the α/β-globin probe did not recognize complementary sequences on the chromosomes of the white-blooded species
Chionodraco hamatus and Channichthys rhinoceratus. These results represent the first example of chromosomal mapping of embryonic/juvenile globin genes in teleostean fishes.
Beyond its relevance to the evolutionary history of Antarctic notothenioids, this work contributes to our understanding of
the evolution of the chromosomal loci of globin genes in fishes and other vertebrates.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
78.
老年病人鼻饲方法的改进 总被引:16,自引:2,他引:14
目的探讨增加置管深度并抬高床头对预防老年鼻饲病人食物反流的效果。方法将 5 75例需鼻饲的卧床老年病人按鼻饲医嘱时间顺序及不平衡指数最小原则分成三组 ,分别给予教科书中的常规置管深度置管 (对照组 )、置管深度延长 10cm(观察 1组 )、置管深度延长 10cm并抬高床头 30~ 45°(观察 2组 )进行鼻饲。结果三组病人食物反流率比较 ,P <0 .0 1;观察 1、2组分别与对照组比较 ,P <0 .0 5、P <0 .0 1;观察 1组与观察 2组比较 ,P <0 .0 1。增加置管深度并抬高床头其食物反流率最低 ,仅增加置管深度次之 ,常规置管最高。结论增加置管深度并抬高床头可显著降低老年鼻饲病人食物反流发生率。 相似文献
79.
The authors report a spiny dogfish (Squalus cubensis/megalops group) sting of a professional fisherman. He was injured on the left hand by the spine anterior to the fish's dorsal fin and manifested local edema, erythema, and excruciating pain for 6 h. Sharks of the genus Squalus megalops/cubensis and Squalus acanthias are found throughout the world; they have two spines in front of their dorsal fins and channels with a whitish mass containing large vacuolated cells which secrete venom. The Squalus genus has a complex taxonomy; the species involved in this injury belongs to the megalops/cubensis group. A detailed taxonomic and toxinological study on the Squalus genus is important and would complement other work on these fish, especially as stings in humans are very rare and not fully understood. 相似文献
80.
Dr. med. Thorsten Schäfer Heike Vogelsang 《Somnologie - Schlafforschung und Schlafmedizin》2002,6(2):79-84
Summary Question of the study Nasal continuous positive airway pressure (CPAP) prevents collapse of the upper airway during sleep in patients with obstructive sleep apnea provided that a positive transmural pressure can be maintained during inspiration. We examined pressure-flow characteristics in seven CPAP and bilevel devices during spontaneous breathing.
Methods The CPAP devices were set to a pressure level of 9.8 hPa (10 cm H2 O) and adapted to a pneumotachograph using a standard CPAP hose and an outlet valve. We continuously measured flow, volume and pressure during resting ventilation and increasing voluntary hyperventilation and analysed the dependence of the variables on a breath-to-breath basis.
Results Mean CPAP pressures differed between the devices (9.9 – 10.6 hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8 hPa and increased during expiration to 11.1 – 11.7 hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19 hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16 hPa. Inspiratory pressures dropped to 8.5 – 4.5 hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated. 相似文献
Methods The CPAP devices were set to a pressure level of 9.8 hPa (10 cm H
Results Mean CPAP pressures differed between the devices (9.9 – 10.6 hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8 hPa and increased during expiration to 11.1 – 11.7 hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19 hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16 hPa. Inspiratory pressures dropped to 8.5 – 4.5 hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated. 相似文献