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161.
本文应用放射免疫分析方法,测定了16只哮喘豚鼠初级传入系统和中枢内神经激肽β(NKB)的水平。结果表明,与正常对照组(结状神经书3228±11.89,C7~C8段脊神经节23.63±13.26,T1~T2段脊神经节24.25±1819,T3~T5段脊神经节25.53±12.34,C7~T5段脊髓后角28.65±16.59,孤束核26.34±18.36Pg/gwettissue)相比较,哮喘豚鼠初级传入系统和中枢内(结状神经节43.26±12.35,C7~C段脊神经节32.53±17.63,T1~T2段神经书32.25±20.65,T3~T5段脊神经节34.36±15.33,C7~T5段脊髓后角39.53±2028,孤束核3662±17.85Pg/gwettissue)NKB的含量明显高于对照组(P<0.05)。结合NKB在呼吸道的作用,这些结果提示,初级传入系统和中枢内的NKB可能参与哮喘发病的病理生理机制。  相似文献   
162.
BACKGROUND: Asthma is a common chronic disease and information on its management practices at the community level is helpful in identifying problems and improving asthma care. OBJECTIVE: To assess the severity status and management of the asthma symptom of wheeze of children at the community level in Hong Kong (HK) and Guangzhou (GZ). METHODS: Cross-sectional study of children aged 10 years using the International Study of Asthma and Allergic disease in Childhood (ISAAC Phase II protocol). Asthma management and lung function were assessed in 178 (98 from HK and 80 from GZ) randomly selected children with wheeze over the past 12 months. RESULTS: Eighty-three percent, 11%, 6% and 0% of children suffered from intermittent, mild persistent, moderate persistent and severe persistent asthma, respectively, according to the frequency of their symptoms. Addition of spirometric parameter only changed the asthma severity classification in 2.8% of children. Medications were used by 30.6% and 71.3% of children for wheeze in HK and GZ, respectively. In HK, inhaled beta(2)-agonist (73.3% among the drug users) was the commonest medication used followed by inhaled corticosteroid (ICS) (23.3%). In GZ, inhaled beta(2)-agonist was used by 75.4% of children, but use of ICS (26.3%), oral beta(2)-agonist (26.3%), oral theophylline (45.6%), oral ketotifen (36.8%) and oral steroid (35.1%) were also common. ICS was only used by 11.4% of children with persistent asthma. Ten percent and 18.7% of children in HK and GZ, respectively, had emergency department visits, while 16.3% and 11.6% of children in HK and GZ, respectively, had missed school secondary to asthma over the past 1 year. CONCLUSIONS: Most children in the community had intermittent asthma and addition of lung function to symptoms did not significantly affect classification of asthma severity. Significant morbidity was seen even in this group of children with mostly intermittent and mild persistent asthma.  相似文献   
163.
Advances in allergy management   总被引:4,自引:1,他引:4  
P. Van Cauwenberge 《Allergy》2002,57(S75):29-36
Our understanding of the pathophysiology of allergy has moved to the molecular level, while study of epidemiology and genetics has revealed risks of developing allergies based on environmental and genetic profiles, and pharmacoeconomic data have enabled accurate measurement of the immense burden of allergic disease. These advances in allergy research have affected its management, particularly the search for new antiallergy therapies. New therapies should intervene in the systemic allergy inflammatory cascade and provide clinical efficacy that extends to multiple allergic disease states. In addition, these new therapies should present no additional safety issues, offer improvements over existing therapies, and have an impact on disease-impaired quality of life. In vitro studies show that desloratadine, a new, once-daily, nonsedating, selective histamine H1-receptor antagonist, blocks the systemic allergy cascade at multiple points. Desloratadine 5 mg once daily relieves the symptoms of chronic idiopathic urticaria and of both seasonal (SAR) and perennial allergic rhinitis. In patients with concomitant asthma and SAR, asthma symptoms are relieved and β2-agonist medication use is decreased by desloratadine. Unlike many other second-generation histamine H1-receptor antagonists, desloratadine provides the added benefit of efficacy against nasal obstruction in SAR. Desloratadine improves quality of life by decreasing the impact of allergic symptoms on sleep and on daily activities.  相似文献   
164.
165.
Recent results of allergen immunotherapy research have continued to validate efficacy and have also demonstrated a truly preventive aspect for this treatment. This review summarizes the basic principles of effective allergen immunotherapy and highlights some of the advances that have been published in the past year. These studies show that allergen immunotherapy, when done appropriately and properly, not only causes a decrease in symptoms and use of medication as well as an improved quality of life, but that the progression of disease from allergic rhinitis to asthma is substantially decreased and the development of new allergies is diminished. In addition, laboratory studies continue to demonstrate significant changes in the immune system with a shift in the immune pathway from TH2 toward a TH1 response. The impact of anti-IgE as a therapeutic agent with allergen immunotherapy is also be reviewed.  相似文献   
166.
167.
Bucková D  Hollá LI  Schüller M  Znojil V  Vácha J 《Allergy》2003,58(10):1023-1026
BACKGROUND: Immunoglobulin E (IgE)-mediated allergy belongs to common chronic disorders resulting from an interaction between both genetic and environmental factors. The gene encoding CD14 is a positional candidate gene for allergic diseases as it is localized on chromosome 5q31.1, a region that is linked to asthma and bronchial hyperresponsiveness. Recently, several polymorphisms in the promoter region of this gene have been associated with atopic phenotypes in various populations. METHODS: We investigated relationship among atopic phenotypes and two polymorphisms [C(-159)T and G(-1359)T] in the promoter of the CD14 gene in the Czech population. Polymerase chain reaction with restriction fragment length polymorphism analyses was used to determine the CD14 genotypes in subjects with IgE-mediated allergic diseases (n = 562) and random controls (n = 320). RESULTS: The CD14 allele or genotype distributions were similar in patients and control group. However, the frequency of the C allele of the C(-159)T polymorphism was higher in patients with positive skin prick tests for moulds than in patients without reactivity to this antigen (P < 0.002, Pcorr<0.01). In addition, we found that patients with homozygous genotype (GG) of the G(-1359)T polymorphism had marginally lower percentage of positive skin prick tests compared with the other genotypes (P < 0.029, Pcorr > 0.05). CONCLUSIONS: Our study supports the idea that CD14 gene variants may act as disease modifiers of IgE-mediated allergic diseases.  相似文献   
168.
Steger A  Radon K  Pethran A  Nowak D 《Allergy》2000,55(4):376-381
BACKGROUND: Three workers engaged in the manufacture of natural thickener products (Cassia spp., guar, and tamarind flour) were occupationally sensitized to Cassia spp. Therefore, a cross-sectional study on the prevalence of sensitization among and respiratory health of the employees of this plant was conducted. METHODS AND RESULTS: Sixty-two workers (36 with high, 26 with low exposure) participated in the survey. Skin prick tests and specific IgE tests with extracts of these components revealed that 11.3% were sensitized to Cassia spp. and 9.7% to at least one species of storage mites, with a significantly higher portion of atopic subjects in the sensitized group. Overall, 55% of the subjects reported work-related symptoms (upper and lower airways, eyes, or skin). FVC % pred. was significantly lower in highly exposed workers, while RV % pred. and RV%TLC % pred. were significantly higher in this group. In the multivariate model, sensitization was not a risk factor for impairment of lung function. CONCLUSIONS: Dust exposure to flours may not only cause allergic sensitization but also induce chronic changes in lung function.  相似文献   
169.
Formoterol administered by a dry-powder (DP) capsule inhaler was compared with a pressurized metered-dose inhaler (pMDI) with regard to bronchodilating and systemic effects. The study used a double-blind, crossover, double-dummy technique. Twelve patients with moderate reversible asthma in a stable phase were examined on two separate study days, and the inhalers were given in randomized order. After baseline measurements, increasing doses of formoterol were given at intervals of 75 min. FEV1 and heart rate and tremor measurements were repeated after each dose, and the doses were 12 + 12 + 24 + 48 μg, giving a total dose of 96 μg. The peak expiratory flow rate (PEFR) was recorded in the morning before the first dose, after the last dose, and then repeatedly at home until 19 h after the last dose. There was an equal increase in ventilatory capacity at each dose level, independent of inhaler device. Repeated PEFR measurements after the last dose did not reveal any differences in duration of effect. There was a slight but statistically significant increase in heart rate and tremor after the highest doses of the DP formulation compared to the pMDI. These systemic effects can probably be explained by the reduced oral deposition of the aerosol caused by using a spacer. This study indicates that the DP and pMDI formulations of formoterol are equipotent in bronchodilation.  相似文献   
170.
Svendsen UG, Frølund L, Heinig JH, Madsen F, Nielsen NH, Weeke B. High-dose inhaled steroids in the management of asthma. A comparison of the effects of budesonide and beclomethasone dipropionate on pulmonary function, symptoms, bronchial responsiveness and the adrenal function.
The efficacy of budesonide (800 μg b.d.) and beclomethasone dipropionate (750 μg b.d.) in controlling the symptoms of asthma, pulmonary function, bronchial responsiveness to histamine, and adrenal function, was assessed in a double-blind, double-dummy cross-over study of 36 adult chronic asthmatic patients. The patients, the majority of whom were assessed to be affected to a severe degree, were insufficiently controlled in their current regimen of inhaled steroids and/or inhaled and oral bronchodilators. A 2 weeks baseline period preceded 6 weeks of treatment with each of the study drugs. Both treatment groups showed improvements from baseline in clinical assessment of lung function carried out after the first 6 weeks of treatment. No significant differences were seen throughout the entire 12 weeks study, when comparing the effects of the treatments on FEV1 FVC, PEF or the histamine PC20. Asthma severity, symptom score and inhaled bronchodilator use showed the same results after both treatments. It is concluded that inhalations of budesonide and beclomethasone dipropionate in high doses are equally potent in the treatment of severe asthma. There is no significant influence on the adrenal function and no significant side effects during a period equal to that of the present study.  相似文献   
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