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排序方式: 共有791条查询结果,搜索用时 15 毫秒
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进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献
3.
Hydrolysis of peptides within lumen of small intestine 总被引:2,自引:0,他引:2
4.
Elliott L Heederik D Marshall S Peden D Loomis D 《The Journal of allergy and clinical immunology》2005,116(1):127-132
BACKGROUND: Laboratory animal allergy is a common illness among workers exposed to laboratory animals and can progress to symptoms of asthma. OBJECTIVES: This study evaluates the continuum of disease from allergy symptoms to asthma symptoms in a dynamic cohort of workers exposed to animals in a pharmaceutical company. METHODS: Data arose from annual questionnaires administered to workers in a surveillance program established to monitor exposure to animals and the development of allergy. The life-table method was used to compare asthma-free survival between workers with and without symptoms of allergy. A Cox proportional hazards model was used to examine the effects of covariates on the development of asthma. RESULTS: A total of 603 workers contributed 2527.4 person-years to the study over the 12.3-year period. The probabilities of experiencing asthma symptoms by the 11th year of follow-up were 0.367 for workers with allergy symptoms and 0.052 for those without allergy symptoms. The hazard ratio for asthma symptoms when comparing workers with and without allergy symptoms was 7.39 (95% CI, 3.29-16.60) after adjustment for sex and family history of allergy. Female subjects developed asthma at a rate 3.4 times that of male subjects. CONCLUSIONS: This study supports the hypothesis that laboratory animal allergy symptoms are a major risk factor for the development of asthma. It also suggests a heightened risk of asthma for women who work with laboratory animals, a finding that has not been previously reported. 相似文献
5.
Erik R Svendsen Karin B Yeatts David Peden Susan Orton Neil E Alexis John Creason Ronald Williams Lucas Neas 《Annals of allergy, asthma & immunology》2007,99(3):244-253
BACKGROUND: Identifying baseline inflammatory biomarkers that predict susceptibility to size-specific particulate matter (PM) independent of gaseous pollutants could help us better identify asthmatic subpopulations at increased risk for the adverse health effects of PM. OBJECTIVE: To evaluate whether the association between lung function and exposure to ambient levels of PM less than 2.5 microm in diameter (PM2.5) (fine) and 10 to 2.5 microm in diameter (PM(10-2.5)) (coarse) in children with persistent asthma differed across baseline measures of inflammation and innate immune activation. METHODS: We performed a panel study on a local population of 16 children with persistent asthma and evaluated daily pulmonary function (percentage of predicted peak expiratory flow and forced expiratory volume in 1 second) while concurrently measuring daily PM2.5 and PM(10-2.5) exposure from a central site in Chapel Hill, North Carolina. The children underwent a baseline medical evaluation that included assessment of several immunoinflammatory biomarkers in peripheral blood. RESULTS: Children without measurable CD14 expression on circulating neutrophils had significantly reduced pulmonary function (forced expiratory volume in 1 second and peak expiratory flow) with each interquartile range (IQR) increase in PM2.5 (IQR = 8.5 microg/m3) and PM(10-2.5) (IQR = 4.1 microg/m3) concentration, unlike children with measurable CD14 expression (P < .001 for interaction). CONCLUSIONS: Asthmatic children with muted surface expression of CD14 on circulating neutrophils may have a decreased capacity to respond to bacterial components of PM. 相似文献
6.
Terry L Noah Gail E Tudor Sally S Ivins Paula C Murphy David B Peden Frederick W Henderson 《Annals of allergy, asthma & immunology》2006,96(2):304-310
BACKGROUND: Inflammatory processes at the mucosal surface may play a role in maintenance of asthma pathophysiology. Cross-sectional studies in asthmatic patients suggest that chemokines such as interleukin 8 (IL-8) are overproduced by respiratory epithelium. OBJECTIVE: To test the hypothesis that chemokine levels are persistently elevated in the respiratory secretions of asthmatic children at a stable baseline. METHODS: We measured nasal lavage fluid (NLF) levels of chemokines and other mediators at 3- to 4-month intervals in a longitudinal study of asthmatic children, with nonasthmatic siblings as controls. RESULTS: In a linear mixed-model analysis, both family and day of visit had significant effects on nasal mediators. Thus, data for 12 asthmatic-nonasthmatic sibling pairs who had 3 or more same-day visits were analyzed separately. For sibling pairs, median eosinophil cationic protein levels derived from serial measurements in NLF were elevated in asthmatic patients compared with nonasthmatic patients, with a near-significant tendency for elevation of total protein and eotaxin levels as well. However, no significant differences were found for IL-8 or several other chemokines. Ratios of IL-13 or IL-5 to interferon-gamma released by house dust mite antigen-stimulated peripheral blood mononuclear cells, tested on a single occasion, were significantly increased for asthmatic patients. CONCLUSIONS: Substantial temporal and family-related variability exists in nasal inflammation in asthmatic children. Although higher levels of eosinophil cationic protein are usually present in NLF of patients with stable asthma compared with patients without asthma, chemokines other than eotaxin are not consistently increased. Eosinophil activation at the mucosal surface is a more consistent predictor of asthmatic symptoms than nonspecific elevation of epithelium-derived inflammatory chemokine levels. 相似文献
7.
Summary The relationships of VII and VIII cranial nerves and related arteries are reviewed in 26 preparations by microdissection techniques. These vessels may be grouped in large (AICA, PICA), medium (LA, SA, CSA, RPI) and small calibre (vasa nervorum, radicullar and medullar branches). The importance of these structures in acoustic neuroma surgery, vestibular neurectomy and cross-compression syndromes is discussed. Vascular loops and elongated arteries are normal structures present at birth.This work was supported by a grant from the AJ Roemmers Foundation 相似文献
8.
Differential pattern of DNA-aneuploidy in human malignancies 总被引:5,自引:0,他引:5
Th Büchner W Hiddemann B Wörmann B Kleinemeier J Schumann W Göhde J Ritter K.-M Müller DB von Bassewitz A Roessner E Grundmann 《Pathology, research and practice》1985,179(3):310-317
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
In addition to its more widely recognized role in promoting IgE synthesis, we speculate that interleukin-4 (IL-4) may modulate both allergic- and nonallergic-type inflammatory processes in the airway mucosa. We examined in vivo the effect of IL-4 on granulocyte and cytokine homeostasis in the nasal airways of nonallergic volunteers. Ten (N = 10) healthy subjects received nasal IL-4 (10 microg) or saline (0.9%) challenges on separate occasions. Nasal lavage was obtained before and 24 h after nasal challenges. We report that IL-4 induced a significant increase in IL-6 and produced elevated levels of eosinophils and neutrophils compared to saline. These data demonstrate that IL-4 can modulate both allergic- and nonallergic-type inflammatory responses in the nasal airways of nonallergic individuals. 相似文献
10.
Recent data demonstrate that atopic inflammation might enhance airway responses to inhaled LPS in individuals with atopic asthma by increasing CD14 expression on airway macrophages. We sought to determine whether blunting airway eosinophilic inflammation decreases CD14 expression and the subsequent airway polymorphonuclear neutrophil (PMN) response to inhaled LPS in subjects with atopic asthma. Twelve such subjects underwent a 2-week, placebo-controlled trial of inhaled steroid (440 microg fluticasone propionate [FP] twice per day); this was followed 48 hours later by an inhaled LPS (5 microg) challenge. A comparison of LPS-induced inflammatory cells in sputum, CD14 expression, and methacholine responsiveness with FP or placebo was conducted. Flow cytometry was used to analyze membrane-bound CD14 expression (mean fluorescence intensity) on sputum macrophages. We report that 48 hours before inhaled LPS challenge (baseline), FP significantly blunted airway eosinophils (cells per milligram; P =.04) and mCD14 expression (mean fluorescence intensity; P =.03) but did not decrease the number of PMNs (cells per milligram). Six hours after LPS challenge, airway PMNs and mCD14 expression were significantly decreased for FP in comparison with placebo (P =.04). Our data suggest that decreasing airway allergic inflammation with corticosteroids results in both decreased expression of CD14 on airway monocytic cells and a decreased PMN response to inhaled LPS. 相似文献