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71.
BACKGROUND: Bronchial responsiveness (BR) to histamine or methacholin is a common finding in adult non-asthmatic patients with allergic rhinitis. OBJECTIVE: We tested whether BR is also present in children with a comparatively short history of allergic rhinitis in a paediatric cohort. METHODS: We performed pulmonary function tests and histamine challenges in a total of 654 children (age 7 years, participants of the German Multicenter Allergy Study) and compared PC20 FEV1 values in children with asthma, allergic rhinitis, asymptomatic allergic sensitization and non-atopic controls. RESULTS: Most pronounced BR to histamine was observed in allergic asthmatics (n = 28), irrespective of the presence or absence of allergic rhinitis. Furthermore, PC(20)FEV(1) values in non-asthmatic children with allergic rhinitis (n = 24) were not significantly different from those seen in asymptomatic atopic (n = 54) or non-atopic controls (n = 92). CONCLUSIONS: In contrast to adult study populations, 7-year-old non-asthmatic children with allergic rhinitis do not show a higher degree of BR than asymptomatic atopic or non-atopic controls. Therefore, secondary preventive measures in non-asthmatic children with allergic rhinitis (such as regular local anti-inflammatory therapy or specific immunotherapy) should be studied and applied more intensely to prevent bronchial hyper-responsiveness (BHR) and asthma in this high-risk group.  相似文献   
72.
A methodological overview is provided on the important question of how to confirm occupational asthma in routine work. Recent knowledge gained in immunology and occupational allergy has been utilized, supplemented by an overview of recent publications on the diagnosis and pathophysiology of occupational asthma. The aim of the paper is to facilitate decision making for an investigator dealing with individual cases of occupational asthma. Moreover, by presenting stepping-stones in the diagnostic cascade, the author hopes to encourage the less experienced to conduct a comprehensive and cause-oriented diagnostic procedure. Methods which are being worked on at present (standardization) are discussed in more detail. Finally, the research goals in the understanding, confirmation, and prevention of occupational asthma are listed.  相似文献   
73.
W. A. Shaikh 《Allergy》1992,47(4):327-330
Inhaled beclomethasone dipropionate (BDP) has been used with few side effects in the treatment of bronchial asthma for 2 decades. Until now the manifestation of tuberculosis (TB) in patients on inhaled BDP has not been reported. Eight patients with allergic asthma, of a total of 548 asthmatics (1.46%) seen over a 2-year period, developed active TB following the use of inhaled BDP. All were sputum-positive for acid-fast bacilli (AFB) on smear and/or culture, all responded well to a combination of anti-TB drugs, and none showed evidence of immunological or pituitary-adrenal suppression. Two patients agreed to a repeat administration of BDP; both developed TB again within 2 weeks and are again on anti-TB treatment.  相似文献   
74.
色甘酸钠混悬气雾剂与茶碱缓释胶囊治疗中度哮喘的比较   总被引:1,自引:1,他引:0  
84例中度哮喘病人分成2组。色甘酸钠组(男性23例,女性20例,年龄26±s8a)吸入色甘酸钠混悬气雾剂10.5mg,tid。茶碱缓释胶囊组(男性22例,女性19例,年龄27±8a)口服0.25g。bid。2组均连续观察3mo。结果:色甘酸钠在减轻病人慢性症状、改善肺功能和降低气道高反应性等方面优于茶碱缓释胶囊,(P<0.01)。而后药仅可缓解近期症状。  相似文献   
75.
BACKGROUND: Although 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), a product of 15-lipoxygenase (15-LO), may be involved in mild to moderate asthma, little is known about its potential roles in severe asthma. OBJECTIVES: This study was performed to evaluate 15(S)-HETE levels in bronchoalveolar lavage fluid (BALF) from severe asthmatics with and without airway eosinophils and from the control groups. In addition, 15-LO protein expression was examined in endobronchial biopsy, while its expression and activation were evaluated in BAL cells. RESULTS: While 15(S)-HETE levels in BALF were significantly higher in all severe asthmatics than normal subjects, severe asthmatics with airway eosinophils had the highest levels compared with mild, moderate asthmatics and normal subjects. 15(S)-HETE levels were associated with tissue eosinophil numbers, sub-basement membrane thickness and BALF tissue inhibitor of metalloproteinase-1 levels, and were accompanied by increased 15-LO expression in bronchial epithelium. In addition, activation of 15-LO was suggested by the increased proportion of 15-LO in the cytoplasmic membrane of alveolar macrophages from severe asthmatics. CONCLUSION: The data suggest that severe asthmatics with persistent airway eosinophils manifest high levels of 15(S)-HETE in BALF, which may be associated with airway fibrosis. It is likely that 15-LO expression and activation by airway cells explain the increased 15(S)-HETE levels.  相似文献   
76.
BACKGROUND: Low-dose allergen challenge (LDAC) may be a useful tool for studying the capacity of allergens to induce airway inflammation in atopic subjects. OBJECTIVE: To evaluate lower airway inflammatory changes following repeated inhalation of very low doses of allergen (VLDAC) in non-asthmatic subjects with allergic rhinitis (NAAR) compared with mild allergic asthmatic subjects (AA). METHODS: Fourteen NAAR and 11 AA were seen out of the pollen season and had skin prick tests with common aeroallergens. Baseline spirometry (S) and methacholine challenge (MC) were done and blood and induced sputum (IS) differential cell counts were obtained. Each subject underwent VLDAC on four consecutive mornings with a relevant allergen. S, MC, and blood and IS samplings were repeated 6 h after the second and fourth VLDAC and one week later. RESULTS: Although there were, as expected, no changes in FEV1 or PC20 in either group, mean percentage eosinophils on IS were significantly increased in NAAR on day 2 of VLDAC and decreased in all but one subject on day 4, with a tendency to return to baseline levels one week later. In AA, there was a non-significant trend for sputum eosinophils to increase on day 2; four subjects showed a decrease of eosinophils on day 4 of VLDAC. There was a correlation between eosinophil cationic protein (ECP) levels and eosinophil counts in NAAR throughout the study. There were no variations in other sputum cells or blood inflammatory cells. CONCLUSION: VLDAC can increase the percentage of eosinophils in IS of NAAR subjects without associated respiratory symptoms nor physiological modifications. A reduction in eosinophilic response despite repeated exposure, more common in NAAR subjects, suggests an adaptation process that needs to be further evaluated.  相似文献   
77.
78.
BACKGROUND: Frequent infection in infancy and early childhood has been hypothesized to explain the low prevalence of asthma and other atopic disease among children in developing countries (the so-called 'hygiene hypothesis'), but the low prevalence in Eastern Europe remains unexplained. OBJECTIVE: To test the hygiene hypothesis in the Republic of Belarus by examining the relationship between gastrointestinal (GI) and respiratory infection and two potentially atopic outcomes in the first 12 months of life: atopic eczema and recurrent wheeze. METHODS; We carried out two case-control studies nested within a large (n=17 046) randomized trial in Belarus, with cases defined as (1) first occurrence of atopic eczema (n=819) and (2) second episode of wheezing (n=112). Incidence density sampling was used to select four matched controls born within 1 month at the same hospital as the case. Exposure was defined as one or more episodes of GI or respiratory infection (examined separately) with onset >7 days before onset of the case's atopic outcome. Analyses controlled for family atopic history, duration of exclusive breastfeeding, sex, birth weight, maternal education, and (for recurrent wheeze) maternal smoking. RESULTS: For atopic eczema, prior GI infection occurred in 7.4% of cases vs. 6.0% of controls [adjusted OR=1.27 (0.94-1.72)] and prior respiratory infection in 35.2% vs. 32.6% [adjusted OR=1.14 (95% CI=0.94-1.37)]. For recurrent wheeze, prior GI infection occurred in 9.8% of cases vs. 7.4% of controls [adjusted OR=1.30 (0.60-2.82)]. CONCLUSION: Our results do not support the hypothesis that infection protects against atopic eczema or recurrent wheezing in the first 12 months of life.  相似文献   
79.
80.
本文对12例支气管哮喘病人作了22例次支气管肺泡灌洗,其中3例次为重度哮喘发作;8例次为中度发作[1];11例次为缓解期.灌洗方法在一般肺灌洗的基础上经过改良后,12例病人无1例死亡.11例次哮喘发作患者,灌洗后临床症状皆有不同程度改善.11例次缓解期病人,灌洗后皆无不良反应.凡哮喘时间较长者,均能灌洗出较大量脓痰栓.  相似文献   
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