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101.
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
102.
103.
目的实验性自身免疫性前葡萄膜炎(EAAU)是研究人前葡萄膜炎的有用模型。本研究旨在观察前房相关免疫偏离(ACAID)能否阻止EAAU发生。方法将溶于磷酸盐缓冲液(PBS)的牛黑色素蛋白(BMP)注射于大鼠右眼前房;对照组动物仅注射PBS。7d后,使用添加完全福氏佐剂(CFA)的BMP和百日咳毒素免疫所有动物。通过临床观察和组织病理学检测葡萄膜炎的严重程度和发病率。通过由注射BMP刺激的足垫水肿反应评估迟发型超敏反应(DTH)。结果与对照组相比,预先眼内注射BMP的大鼠,其EAAU的严重程度和发病率减低,且DTH反应受到显著抑制。结论这些资料提示ACAID可以用来阻止EAAU的发生。 相似文献
104.
Summary The effects of cocaine on the contractile response of isolated human nasal mucosal blood vessels to field stimulation and methoxamine were investigated. Results showed that cocaine antagonized methoxamine and inhibited field stimulation. The drug increased resting tension in human nasal mucosa in vitro through direct actions and potentiated mucosal contractions by norepinephrine and epinephrine. The study indicated that high concentrations of cocaine may actually antagonize -adrenoceptors, but these concentrations are not necessary in eliciting desired degrees of vasoconstriction in nasal blood vessels while being applied as a local anesthetic. 相似文献
105.
Absorption Enhancing Effect of Cyclodextrins on Intranasally Administered Insulin in Rats 总被引:4,自引:0,他引:4
Merkus Frans W. H. M. Verhoef J. Coos Romeijn Stefan G. Schipper Nicolaas G. M. 《Pharmaceutical research》1991,8(5):588-592
The absorption enhancing effect of -, -, and -cyclodextrin (CD), dimethyl--cyclodextrin (DMCD), and hydroxypropyl--cyclodextrin (HPCD) on intranasally administered insulin was investigated in rats. Coadministration of 5% (w/v) DMCD to the insulin solution resulted in a high bioavailability, 108.9 ± 36.4% (mean ± SD, n = 6), compared to i.v. administration, and a strong decrease in blood glucose levels, to 25% of their initial values. Coadministration of 5% -CD gave rise to an insulin bioavailability of 27.7 ± 11.5% (mean ± SD, n = 6) and a decrease in blood glucose to 50% of its initial value. The rate of insulin absorption and the concomitant hypoglycemic response were delayed for the -CD-containing solution as compared to the DMCD preparation. The other CDs, HPCD (5%), -CD (1.8%), and -CD (5%), did not have significant effects on nasal insulin absorption. DMCD at a concentration of 5% (w/v) induces ciliostasis as measured on chicken embryo tracheal tissue in vitro, but this effect is reversible. In conclusion, DMCD is a potent enhancer of nasal insulin absorption in rats. 相似文献
106.
R P Gaykema R van Weeghel L B Hersh P G Luiten 《The Journal of comparative neurology》1991,303(4):563-583
The prefrontal cortex (PFC) projections to the basal forebrain cholinergic cell groups in the medial septum (MS), vertical and horizontal limbs of the diagonal band of Broca (VDB and HDB), and the magnocellular basal nucleus (MBN) in the rat were investigated by anterograde transport of Phaseolus vulgaris leuco-agglutinin (PHA-L) combined with acetylcholinesterase (AChE) histochemistry or choline acetyltransferase (ChAT) immunocytochemistry. The experiments revealed rich PHA-L-labeled projections to discrete parts of the basal forebrain cholinergic system (BFChS) essentially originating from all prefrontal areas investigated. The PFC afferents to the BFChS display a topographic organization, such that medial prefrontal areas project to the MS, VDB, and the medial part of the HDB, whereas the orbital and agranular insular areas predominantly innervate the HDB and MBN, respectively. Since the recurrent BFChS projection to the prefrontal cortex is arranged according to a similar topography, the relationship between the BFChS and the prefrontal cortex is characterized by reciprocal connections. Furthermore, tracer injections in the PFC resulted in anterograde labeling of numerous "en passant" and terminal boutons apposing perikarya and proximal dendrites of neurons in the basal forebrain, which were stained for the cholinergic marker enzymes. These results indicate that prefrontal cortical afferents make direct synaptic contacts upon the cholinergic neurons in the basal forebrain, although further analysis at the electron microscopic level will be needed to provide conclusive evidence. 相似文献
107.
Immune deviation and the hygiene hypothesis: A review of the epidemiological evidence 总被引:4,自引:0,他引:4
The epidemiological evidence for the proposal that early life immune deviation is the principal mechanism by which microbial agents prevent the development of atopy has been reviewed. Seven criteria are proposed which should ideally be fulfilled. The majority of studies only fulfill two or three criteria. For mycobacteria, measles and respiratory viruses there are studies that demonstrate a significant increase in atopy or allergic disease. Parasite infections, which provide a strong TH2 stimulus, are associated with reduced rather than enhanced allergen sensitization. The available epidemiological evidence does not provide support for a mechanism of early life immune deviation. The principal environmental influences on atopic disease are likely to occur throughout life and involve interactions between microbes and other non-infective and lifestyle factors. 相似文献
108.
目的:建立复方酮替芬喷鼻剂中酮替芬的含量测定方法。方法:采用紫外分光光度法不经分离直接测定酮替芬的含量,检测波长为301nm。结果:酮替芬在浓度为5~30μg/ml内呈线性,相关系数r=0.9999。浓度为7.5、15、30μg/ml的样品液,日内RSD分别为2.68%、1.00%和1.61%,日问RSD分别为2.80%、0.90%和0.81%。浓度为7.5、15、30μg/ml的样品液的平均回收率分别为99.12%、100.25%、99.62%,RSD分别为3.56%、2.10%和1.93%。结论:本方法简便易行,适合复方酮替芬喷鼻剂中酮替芬的含量测定。 相似文献
109.
T. Akagi K. Hashino Y. Maeno M. Ishii T. Sugimura T. Kawano H. Kato 《Pediatric cardiology》1997,18(1):61-63
Using a commercially available 5F deflectable radiofrequency catheter, we have succeeded in percutaneous valvotomy of an
imperforate pulmonary valve and consecutive balloon dilatation in a baby with pulmonary atresia and intact ventricular septum.
After the procedure, right ventricular systolic pressure fell from 125 mmHg to 65 mmHg, and right ventriculography demonstrated
anterograde blood flow into the pulmonary arteries. There were no major complications. Doppler echocardiography at 1 year
after the procedure demonstrated a pressure gradient across the pulmonary valve of 20 mmHg with mild pulmonary and tricuspid
regurgitations. 相似文献
110.
This paper reports the effects of the H2 antagonist cimetidine on the number of CD4+ and CD8+ cells in nasal mucosa and the IgE level of nasal secretions in patients with allergic rhinitis. The results showed the numbers of CD4+ cells were greater than the numbers of CD8+ cells in nasal mucosa, both in the patients with allergic rhinitis and normal subjects, but the ratio of CD4+ : CD8+ cells was much higher in the patients with allergic rhinitis. After treatment with cimetidine locally for 4 weeks, the numbers of CD4+ cells fell and the numbers of CD8+ cells increased in the patients with allergic rhinitis. The high IgE level of nasal secretion of the patients with allergic rhinitis was much reduced after treatment with cimetidine. The results suggest that there are high numbers of CD4+ cells and lower numbers of CD8+ cells in the nasal mucosa and a high level of IgE in the nasal secretions of the patients with allergic rhinitis. Treatment with cimetidine locally may be of some value to relieve the clinical symptoms of allergic rhinitis. 相似文献