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21.
支气管哮喘患者早期病理形态学改变 总被引:3,自引:1,他引:2
目的:应用电镜对支气管哮喘患者以气管粘膜进行观察,了解支气管病理形态学改变。方法:对持续咳嗽3 ̄12个月的12例哮喘患者,1周内未使用类固醇、妥痉平湍及抗组织胺类药物,行支气管镜常规检查,每例患者取2 ̄3块病理组织行电镜检查。结果:电镜下观察早期哮喘患者已具备了哮喘病理形态学改变,并且还发现线粒体变性、粗面内质网(RER)扩张及髓磷体的出现和轻度钙过载。意义:即使是早期哮喘患者的病理形态学改变也与 相似文献
22.
This study is an extended follow-up for 24 months of a 12-week trial to study the long-term clinical efficacy of low-dose inhaled budesonide (BUD) once or twice daily in children with mild asthma. A total of 122 children (mean age 9.7 years, girls/boys; 42/80) with mild asthma (FEV1 103.7% of predicted, reversibility in FEV1 3.5%, and fall in FEV1 after exercise 12.2%), not previously treated with inhaled steroids, were included in a double-blind, randomized, parallel-group study. The children were treated with inhaled BUD 100 or 200 microg administered via Turbuhaler once daily in the morning, 100 microg twice daily, or placebo for 27 months. Exercise and methacholine challenges were performed at 3-month intervals the first year and at 6-month intervals the second year, in a total of seven visits. A significant dose-response effect favoring BUD 200 microg daily (vs 100 microg daily) was found when comparing changes in FEV1, FEF25%, and FEV50%; the fall in FEV1 after an exercise test; and the effect on blood eosinophils. Bronchial hyperreactivity to methacholine decreased significantly on three visits in patients treated with BUD 200 microg daily compared to placebo. Growth rate was not significantly affected except in children aged 7-11 years at baseline after 12 months of treatment. In conclusion, 100 or 200 microg daily of inhaled BUD for 27 months is safe and effective in protecting against exercise-induced asthma and achieving nearly normal lung function. Baseline lung function was not significantly affected in this group of children with mild asthma. 相似文献
23.
Jang AS Choi IS Lee S Nam HS Kweon SS Son MH Lee JH Park SW Kim DJ Uh ST Kim YH Park CS 《Journal of Korean medical science》2004,19(2):214-217
Passive smoking is a major cause of respiratory morbidity, and is associated with increased bronchial responsiveness in children. To evaluate the effect of smoking by a parent on asthma symptoms, atopy, and airway hyperresponsiveness (AHR), we conducted a cross-sectional survey of 503 schoolchildren that involved questionnaires, spirometry, allergy testing, and a bronchial challenge test. If the PC20 methacholine was less than 16 mg/mL, the subject was considered to have AHR. The prevalence of a parent who smoked was 68.7%. The prevalence of AHR was 45.0%. The sensitization rate to common inhalant allergens was 32.6%. Nasal symptoms such as rhinorrhea, sneezing, nasal itching, and nasal obstruction were present in 42.7%. Asthma symptoms such as cough and wheezing were present in 55.4%. The asthma symptoms were significantly more prevalent in children who had a parent who smoked than in those whose parents did not. The nasal symptoms, atopy, and AHR did not differ according to whether a parent smoked. In a multiple logistic regression model, the asthma symptoms and atopy were independently associated with AHR, when adjusted for confounding variables. Passive smoking contributed to asthma symptoms in schoolchildren and was not an independent risk factor of airway hyperresponsiveness in an epidemiological survey. 相似文献
24.
Cough provocation with capsaicin is an objective way to test sensory hyperreactivity in patients with asthma-like symptoms 总被引:5,自引:0,他引:5
Millqvist E 《Allergy》2000,55(6):546-550
BACKGROUND: A group of patients with asthma-like symptoms and sensitivity to chemical irritants, but without bronchial obstruction, has been found among subjects referred for suspected asthma. They have no well-defined diagnosis, and no objective diagnostic method has previously been available. These patients are more sensitive to inhaled capsaicin than are patients with asthma or healthy controls. The aim was to study cough and other capsaicin-induced symptoms and to test the effect of a drug (lidocaine) that inhibits nerve transmission in sensory nerves. METHODS: Twelve patients were provoked with three different concentrations of inhaled capsaicin solutions in a randomized, double-blind order. They all had asthma-like symptoms and were sensitive to chemical irritants, but had no IgE-mediated allergy or demonstrable bronchial obstruction. Before the provocations, the patients inhaled lidocaine or placebo (saline), also in a double-blind, randomized order. The results were expressed as the number of coughs and scores of various symptoms. RESULTS: The patients reacted in a dose-dependent way with cough, airway, and eye symptoms, which were significantly reduced after preinhalation of lidocaine. CONCLUSIONS: A drug that inhibits transmission in sensory nerves successfully blocked the number of coughs and other symptoms provoked by inhalation of capsaicin. This indicates that the mechanisms underlying chemical sensitivity in these patients may originate in the sensory nervous system, and we call this condition "sensory hyperreactivity". 相似文献
25.
C. DE GRAAF-IN'T VELD I. M. GARRELDS A. P. H. JANSEN A. W. VAN TOORENENBERGEN P. G. H. MULDER J. MEEUWIS R. GERTH VAN WIJK 《Clinical and experimental allergy》1995,25(10):966-973
Background Patients with perennial allergic rhinitis develop nasal symptoms not only after allergen exposure, but generally also after non-specific stimuli. Objective To evaluate the effect of 2 week's treatment with fluticasone propionate aqueous nasal spray (FPANS) on the nasal clinical response, inflammatory mediators and nasal hyperreactivity. Methods Twenty-four rhinitis patients allergic to house dust mite (HDM). participated in a douhle-blind. placebo-controlled crossover study. After 2 week's treatment with placebo or 200 μg FPANS twice daily, patients were challenged with HDM extract. Symptoms were recorded and nasal lavages were collected for up to 9.5 h after challenge. Nasal hyperreaclivity was determined by histamine challenge 24 h later. Results Because of a carry-over effect for the immediate symptom score, for this variable only the data from the first treatment period were used. FPANS treatment resulted in a significant decrease of nasal symptoms with 70%. 69% and 63% after 100. 1000 and 10000 Biological Units (BU)/mL of HDM extract respectively. Active treatment resulted in a 76% decrease of the late-phase symptoms. FPANS treatment significantly reduced albumin influx after HDM 1000 BU/mL with 62% and tended to reduce tryptase release after HDM 1000 BU ml. (P 0.0629). During the late phase FPANS treatment reduced albumin influx with 67% and eosinophil cationic protein (ECP) release with 83%. No effect of FPANS was seen on histamine levels. FPANS significantly decreased histamine-induced symptom score with 34%, secretion with 32%, and sneezes with 41%. Conclusion FPANS significantly inhibits the immediate and late allergic response, and nasal hyperreactivity, probably by suppressing mast cells and eosinophils in the nasal mucosa. 相似文献
26.
Summary Lung function was studied double blind and randomized in 5 patients with mild asthma bronchiale and 10 normal adults before and 30, 60 and 90 minutes after one drop of 0.5% Timolol, 0.6% Metipranolol or 0.9% NaCl in each eye.In the asthmatics bronchoconstriction was seen after both -receptor blocking agents, more pronounced after Timolol than after Metripranolol. There was a decrease in the forced expiratory volume in one second (FEV1.0) of 32, respectively 18%. No changes were observed in the normal subjects.In a separate studie no significant changes were seen in the mean values of 10 other asthmatic subjects after 1% Pindolol, 3% Pilocarpin or 0.9% NaCl.However, in two patients FEV1.0 was reduced by 15% and 20% of the control values after applying Pindolol.In summary, not only -receptorblocking agents without ISA produce a bronchoconstriction in asthmatic subjects, but also -blocker with ISA in individual cases.
Abkürzungen FEV1.0 Ein-Sekunden-Wert - ISA intrinsische sympathikotone Aktivität - MEV maximaler exspiratorischer Fluß - Rtos oszillatorische Resistance Ein Teil der Daten wurde der Dissertationsschrift von Frau Janette Gehre entnommen. 相似文献
Abkürzungen FEV1.0 Ein-Sekunden-Wert - ISA intrinsische sympathikotone Aktivität - MEV maximaler exspiratorischer Fluß - Rtos oszillatorische Resistance Ein Teil der Daten wurde der Dissertationsschrift von Frau Janette Gehre entnommen. 相似文献
27.
《The Journal of allergy and clinical immunology》2019,143(5):1752-1759.e6
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28.
L. Machado 《Allergy》1985,40(8):580-585
The non-specific bronchial reactivity following bronchial allergen challenge was studied in 40 patients with allergic bronchial asthma, particularly in subjects without definite late reactions 6 h after the provocations (reduction in peak expiratory flow or forced expiratory volume in 1 s of less than 15% of the control value at this time). Among a group of 21 patients submitted to bronchial provocation tests, 13 carried out maximal exercise tests 6 and 1 week after the allergen challenge. In another group of 19 patients, the bronchial hyperreactivity to methacholine was assessed before and 6 h and 1 week after challenge. Two patients with a dual response (early & late) reacted with bronchial obstruction to the exercise. Exercise tests performed after 1 week did not provoke asthma in any patient. In the methacholine group a marked increase in responsiveness to methacholine 6 h after the provocation was observed in those patients with a dual response who were tested and in those with equivocal late reactions and even in three patients with an isolated immediate reaction. The increases responsiveness was still present in many patients 1 week after challenge. The airway caliber did not influence the degree of responsiveness to methacholine. Nor did the degree of responsiveness have any influence on the patterns of reactions observed after allergen exposure. It was concluded that in some individuals exposure to the relevant allergen predisposes them to exercise-inducible bronchial obstruction. Further, it was confirmed that non-specific bronchial reactivity can be increased not only in patients with late responses - both definite and equivocal--but also in some patients with immediate reactions alone.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
29.
4-羟基壬烯醛诱导支气管上皮细胞凋亡 总被引:1,自引:0,他引:1
目的探讨4-羟基壬烯醛(4-HNE)对支气管上皮细胞(16-HBE)凋亡的诱导作用及其机制。方法将支气管上皮细胞(16-HBE)分为空白对照组、10μmol/L、30μmol/L、50μmol/L4-HNE作用4h组,观察4-HNE作用4h后的细胞凋亡情况。Western印迹方法检测磷酸化(p-)SAPK-JNK和caspase-3蛋白表达的情况。结果细胞经30μmol/L、50μmol/L4-HNE作用后,姬姆萨染色可见明显细胞凋亡改变。对照组、10μmol/L、30μmol/L、50μmol/L4-HNE组的AnnexinV-PI染色凋亡细胞数分别为1.94±1.03,2.03±1.04,43.36±1.3,65.92±3.45。30μmol/L和50μmol/L4-HNE组与对照组及10μmol/L4-HNE组比较,差异有统计学意义(P<0.01)。各组p-SAPK-JNK蛋白表达差异无统计学意义(P>0.05)。30μmol/L、50μmol/L4-HNE刺激组caspase-3的表达较对照组和10μmol/L4-HNE组差异有统计学意义(P<0.01)。结论30、50μmol/L4-HNE可通过caspase-3的激活引起支气管上皮细胞的凋亡。 相似文献
30.
卡介苗多糖核酸对过敏性支气管哮喘外周血单个核细胞TH1/TH2反应的作用 总被引:5,自引:0,他引:5
目的观察卡介苗多糖核酸(BCG-PSN)对支气管哮喘患者外周血淋巴细胞TH1/TH2反应的作用,并与结核菌素纯蛋白衍生物(TB-PPD)进行比较. 方法缓解期过敏性支气管哮喘患者16例,对照组健康成人13例,分离外周血单个核细胞(PBMC),分别加入不同浓度的BCG-PSN(1、10、100、1000 μg/ml)、TB-PPD(10 μg/ml)、尘螨抗原(DerP, 10 μg/ml)体外培养4 d,不加刺激剂者为阴性对照.收集培养上清,ELISA检测IFN-γ、IL-5浓度的变化. 结果 PSN(1~100 μg/ml)刺激正常人PBMC分泌IFN-γ水平均高于哮喘患者(P<0.05).BCG-PSN(10 μg/ml)可以刺激哮喘患者PBMC分泌IFN-γ(358.7 pg/ml,范围0~2433.0 pg/ml),但显著低于同等浓度的TB-PPD刺激作用(13 036 pg/ml,范围600.5~35 100.0 pg/ml,P<0.01).PSN刺激PBMC分泌IFN-γ呈浓度依赖性,当浓度达到100 μg/ml时,与低浓度相比刺激作用显著增强(P<0.01),与TB-PPD的刺激作用类似.DerP刺激哮喘患者PBMC分泌IL-5水平显著高于正常人(P<0.05).BCG-PSN刺激PBMC分泌IL-5的作用较弱,显著低于TB-PPD和DerP的刺激作用. 结论 BCG-PSN具有一定的TH1刺激作用,但低于TB-PPD的刺激作用,有待对BCG-PSN组分进一步优化以增强疗效. 相似文献