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61.
R. Nickel S. Lau B. Niggemann C. Sommerfeld U. Wahn the German Multicenter Allergy Study Group 《Clinical and experimental allergy》2002,32(9):1274-1277
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
62.
Coppo R; Cirina P; Amore A; Sinico R; Radice A; Rollino C; the Italian Group of Renal Immunopathology Collaborative Study on Henoch-Schonlein purpura in adults f; children i 《Nephrology, dialysis, transplantation》1997,12(11):2269-2276
Background: The presence and the pathogenetic role of
circulating IgA reacting with neutrophil cytoplasmic antigens (IgA-ANCA) in
patients with Henoch-Schonlein purpura (HSP) is still debated. This study
was aimed to investigate some characteristics of serum IgA and
macromolecular IgA in HSP patients, focusing on IgA-ANCA.
Methods: Eighty-seven HSP patients with biopsy proved
renal involvement (51 adults and 36 children) enrolled in a multicentre
study of the Italian Group of Immunopathology were investigated.
Results: Significantly high levels of IgA immune
complexes were found in both adults (P <0.05) and children (P
<0.01), while the binding of IgA to jacalin, was significantly low
in children with HSP (P <0.01) only. Two series of ELISA were done
for IgA-ANCA, in two different laboratories. Increased binding to PMN crude
extracts (P <0.01) without any modification in IgA binding to
proteinase 3 was found by either specific ELISA. Conversely, the binding of
IgA to myeloperoxidase (MPO) was found to be significantly (P <0.05)
increased with positive values in 25% of patients by one assay only. Three
of four sera with positive IgA-MPO ANCA exhibited binding in Western-blot
studies with the MPO preparation used in ELISA to a 28-kDa species.
D-galactose and N-acetyl-glucosamine decreased the binding of serum IgA to
MPO more in HSP than in controls (P <0.05).
Conclusions: The conflicting reports on IgA-ANCA may
reflect some atypical characteristics of the reaction which can be detected
only by some ELISAs. We suggest that not an antigen-antibody reaction but a
lectinic interaction due to abnormal composition of IgA carbohydrate side
chains may account for the IgA-ANCA reaction in patients with HSP
nephritis. 相似文献
63.
A study of the relationship between the delivery to cord clamping interval and the time of cord separation 总被引:1,自引:0,他引:1
A randomised controlled trial of 554 women was carried out to compare the effects of late and early umbilical cord clamping on the time of cord separation. In addition data were collected on maternal and neonatal outcomes. There were no significant differences between the two groups in the duration of cord adherence and neonatal and maternal outcomes. There appeared to be a higher rate of jaundice in the late clamped group which did not reach statistical significance. There was an unexpectedly higher rate of breast feeding at home in the late clamped group which did reach statistical significance. Overall the trial provides no clear evidence for the benefit of early cord clamping (the current policy as part of the active management of the third stage in the UK) on the outcomes considered. 相似文献
64.
我国医院药学的形成与发展 总被引:1,自引:0,他引:1
本文通过对医院药学的形成与发展的讨论,旨在确立该学科(也可说领域)的学术技术内容,尽快形成一个完善的学科,以利推进临床药物治疗学的发展,推进医药科学的进步。 相似文献
65.
均一吸收体中SPECT重建多解性的探讨 总被引:1,自引:0,他引:1
通过对重建图像噪声特性的分析,间接证明SPECT的解具有多样性。分别用TretiakMetz、Gulberg、富谷武浩等推导的3种等价重建方法和Belini等推导的重建方法,经计算机模拟重建衰减均匀分布的图像,先预置相同的重建图像的空间分辨率,再比较它们的噪声特性。两种方法重建图像的噪声分布:前者近图像边缘时增大,而后者减小,从而间接证明在假定均匀衰减条件下,SPECT的重建有多解性。 相似文献
66.
设计、合成了一种新的吗啡受体显像剂。选用吗啡拮抗剂特培洛啡(diprenorphine,DPN),经乙酰化选择性保护苯环3位—OH,将乙烯锡烷作为弥补基引入DPN分子7α支链淑醇基团位置,采用碘代锡烷标记法一步合成碘烷DPN(7αoiodoalyldiprenorphine,即7αoIADPN)。其标记率达90%,比活度为80TBq/mmol,放化纯度大于95%。体外吗啡受体结合分析表明其具有很高的亲和力(Ki=0.4nmol/L)。结果表明:新合成的碘标记吗啡配体适合于SPECT活体吗啡受体显像研究。 相似文献
67.
68.
图形视觉诱发电位(P—VEP)是眼接受图形的刺激时,视路及大脑皮质枕区所产生的一系列电位变化。在视交叉后病变的诊断,病情估计及预后推测中有比较肯定的价值。 本文对17例视交叉后损害的病人进行分析。发现视交叉后病变以视皮质损害为主,表现为视物模糊,视力下降,视野改变。P—VEP检查的异常率与病变部位大小及病变性质有关。同时检查半视野刺激有助于提高阳性率。 相似文献
69.
70.
Solveig B. Larsen Aleksander Giwercman Marcello Spanò Jens P. Bonde The ASCLEPIOS Study Group 《Reproductive toxicology (Elmsford, N.Y.)》1998,12(6):391-589
It was hypothesized that occupational exposure to pesticides during a spraying season causes changes in semen quality that might be detected in a longitudinal study. We analyzed the within-person changes in semen quality and reproductive hormones across a spraying season in groups of farmers using and not using pesticides. A total of 248 men collected two semen samples (participation rate: 32%). The median sperm concentration declined significantly from the first to the second sample in both groups, but there was no statistical difference in the decline between the two groups, unadjusted or adjusted. Only minor changes were found in sperm morphology, vitality, motility, sperm chromatin denaturation (SCSA), and reproductive hormones, and the differences in changes between the two groups were nonsignificant, or, in the opposite direction to the expected. There was no relation between the changes in sperm parameters in relation to pesticide exposure variables. In conclusion, use of pesticides by Danish farmers is not a likely cause of short-term effects on semen quality and reproductive hormones. 相似文献