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51.
BACKGROUND: We recently described patients with soybean allergy mainly mediated by cross-reactivity to birch pollen allergens. A majority of those patients were reported to have peanut allergy. OBJECTIVE: We sought to study the occurrence of peanut allergy in patients allergic to birch pollen and characterized the Bet v 1-homologous peanut allergen Ara h 8. METHODS: Recombinant Ara h 8 was cloned with degenerated primers and expressed in Escherichia coli. Nine Swiss and 11 Dutch patients with peanut and birch pollen allergy and a positive double-blind, placebo-controlled food challenge result to peanut were investigated for IgE reactivity to birch pollen and purified peanut allergens and cross-reactivity between birch and peanut. Ara h 8 stability against digestion and roasting was assessed by means of RAST inhibition. The IgE cross-linking potency of Ara h 8 was tested on the basis of basophil histamine release. RESULTS: During double-blind, placebo-controlled food challenge, all patients experienced symptoms in the oral cavity, progressing to more severe symptoms in 40% of patients. CAP-FEIA detected recombinant (r) Ara h 8-specific IgE in 85%. IgE binding to Ara h 8 was inhibited by Bet v 1 in peanut extract immunoblotting and in RAST inhibition. In EAST inhibition recombinant rAra h 8 inhibited IgE binding to peanut in 4 of 7 tested patient sera. Antipeanut response was dominated by Ara h 8 in 12 of 17 tested patients. Furthermore, our results demonstrate a low stability of Ara h 8 to roasting and no stability to gastric digestion. Basophil histamine release with rAra h 8 was more than 20% in 5 of 7 tested sera. CONCLUSIONS: Peanut allergy might be mediated in a subgroup of our patients by means of cross-reaction of Bet v 1 with the homologous peanut allergen Ara h 8.  相似文献   
52.
We describe the clinicopathological findings in 12 cases of hepatic epithelioid haemangioendothelioma in order to identify diagnostic and prognostic features of this unusual vascular neoplasm. Three main tumour patterns were observed histologically: (1) a peripheral pattern with neoplastic cells scattered between fairly normal liver cell plates; (2) a cellular pattern showing a confusing admixture of pleomorphic tumour cells and atrophied hepatocytes set in a small amount of fibrous stroma; and (3) a scarred pattern with sparse tumour cells in a dense fibrous matrix. There were two types of vascular invasion: tuft-like intravascular proliferations of epithelioid cells and fibro-thrombotic venous occlusions. Awareness of these different aspects is important, as they are variably sampled by biopsy needles. The clinical course in this series was less favourable than that previously reported. Eight patients have died, in six instances of liver failure within 4-41 months of diagnosis. Extensive involvement of both lobes of the liver heralds imminent hepatic failure. The slow growth of metastases may justify liver transplantation in order to prolong life.  相似文献   
53.
精神专科医院门诊抑郁症患者服药依从性影响因素分析   总被引:5,自引:0,他引:5  
目的:探讨影响抑郁症患者服药依从性的影响因素.方法:选取2007年5月至10月于北京大学第六医院及北京回龙观医院门诊就诊的123例抑郁症患者,采用自编抑郁症患者就诊状况及服药依从性调查问卷进行调查,内容包括患者一般情况、患病及就诊情况调查、抑郁症发病次数、巩固治疗期坚持服药时间知晓情况及实际服药情况等.分别采用卡方检验及多元Logistic回归分析,探讨上述各因素与服药依从性的相关性.结果:完全依从组(完全按照医嘱时间和剂量服药的患者)和部分依从组(部分按照医嘱时间和剂量服药的患者)在医疗费用支付形式、病程、家属态度、抑郁症阳性家族史、对疾病性质的认识、就诊模式、第一主诉、患病次数、坚持服药时间知晓情况、家庭平均月收入等方面的差异有统计学意义(P<0.05),将患者服药依从情况作为因变量,将以上项目作为自变量进行Logistic回归,结果显示月收入、对疾病性质的认识、家属态度、就诊模式、医药费支付形式、病程进入回归方程,各变量比值比分别为:10.932、9.604、7.246、6.019、2.611、0.209.结论:抑郁症患者服药依从性与多方面因素相关,对疾病性质的认识、家属态度、就诊模式、医药费支付形式、病程、家庭平均月收入等是影响抑郁症患者服药依从性的重要因素.  相似文献   
54.
A simple numerical simulation of AIDS patient detoxification by a hypothetical extracorporeal device for the removal of viruses, infected white cells, and syncytia has been designed. The mathematical model accounts for healthy blood white cells attacking and destroying the viruses, while at the same time the viruses attack and infect certain white cells. The infected white cells serve as a site for viral growth; eventually the cells lyse, releasing a large number of viruses into the blood stream. The healthy white cells and infected white cells combine to form syncytia, where the virus multiplies, and finally the syncytium ruptures releasing all the virus. This model can be used to predict concentrations over a specified period for the patient. This is a mathematical model to be used as a research and design tool only.  相似文献   
55.
Desmin‐related myopathy is a familial or sporadic disease characterized by skeletal muscle weakness and cardiomyopathy as well as the presence of intracytoplasmic aggregates of desmin‐reactive material in the muscle cells. Previously, two kinds of deletions and eight missense mutations have been identified in the desmin gene and proven to be responsible for the disorder. The present study was conducted to determine structural and functional defects in a pathogenic desmin variant that caused a disabling disorder in an isolated case presenting with distal and proximal limb muscle weakness and cardiomyopathy. We identified a novel heterozygous Q389P desmin mutation located at the C‐terminal part of the rod domain as the causative mutation in this case. Transfection of desmin cDNA containing the patient’s mutation into C2.7, MCF7, and SW13 cells demonstrated that the Q389P mutant is incapable of constructing a functional intermediate filament network and has a dominant negative effect on filament formation. We conclude that Q389P mutation is the molecular event leading to the development of desmin‐related myopathy. Hum Mutat 18:388–396, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   
56.
音乐治疗对眼底手术病人焦虑的影响   总被引:19,自引:0,他引:19  
目的:在于观察经听觉通道输入音乐对眼底手术病人焦虑状态的影响。方法:实验对象为39名择期进行眼底手术的男性病人,他们被随机地分为实验和对照两组,其中实验组19人,对照组20人,在手术过程中通过耳机给患者输入他们自己选定的音乐、观察焦虑(STAI),抑郁(SDS),视觉模拟焦虑(VAS)和脑电(BI)的变化。结果:实验组STAI,SDS,VAS值与对照组比明显降低,病人的焦虑、抑郁情绪有了明显改善,而脑电的变化没有显著性的差异。结论:音乐治疗可降低择期眼底手术男性病人的焦虑、抑郁与视觉模拟焦虑水平。  相似文献   
57.
目的:观察事件相关电位P_(300)、体感诱发电位、视觉诱发电位和脑干听觉诱发电位在亚临床肝性脑病诊断中的意义。方法:50例亚临床肝性脑病患者进行了心理测验,并做了头颅CT和视觉诱发电位、体感诱发电位、脑干听觉诱发电位和事件相关电位检查,30例正常人做为对照组。结果:亚临床肝性脑病的心理测验,韦氏法智力低下率为76%,视觉诱发电位异常率为13%,脑干听觉诱发电位异常率为20%,体感诱发电位异常率为40%,事件相关电位异常率为71%,正常对照组四种诱发电位的正常率是100%。头颅CT结果与亚临床肝性脑病无关。结论:视觉诱发电位、体感诱发电位、脑干听觉诱发电位和事件相关电位在亚临床肝性脑病中是异常的。事件相关电位更为敏感,对亚临床肝性脑病的早期诊断有重要意义。  相似文献   
58.
The event-related responses of 18 individuals were recorded while they were listening to 3 music clips of 6 s duration which were repeated 30 times each. The music clips differed in the level of their complex structure, induced mood, musical tempo and prominent frequency. They were taken from Mozart's sonata (K. 448), and Brahms' Hungarian dance (no. 5). The third clip was a simplified version of the theme taken from Haydn's symphony (no. 94) played by a computer synthesizer. Significant differences in induced event-related desynchronization between the 3 music clips were only observed in the lower-1 alpha band which is related to attentional processes. A similar pattern was observed for the coherence measures. While respondents listened to the Mozart clip, coherence in the lower alpha bands increased more, whereas in the gamma band a less pronounced increase was observed as compared with the Brahms and Haydn clips. The clustering of the three clips based on EEG measures distinguished between the Mozart clip on the one hand, and the Haydn and Brahms clips on the other, even though the Haydn and Brahms clips were at the opposite extremes with regard to the mood they induced in listeners, musical tempo, and complexity of structure. This would suggest that Mozart's music--with no regard to the level of induced mood, musical tempo and complexity--influences the level of arousal. It seems that modulations in the frequency domain of Mozart's sonata have the greatest influence on the reported neurophysiological activity.  相似文献   
59.
目的 探讨 14只成年鼠和 14只老年鼠脑底主要动脉降钙素基因相关肽能神经纤维的分布特征。方法 应用免疫组织化学ABC法、神经交点计数法。结果 成年鼠脑底各主要动脉壁上均含有呈线状黑色的CGRP能免疫反应阳性神经纤维 ,分布密度以大脑前动脉最高 ,其次是大脑中动脉、大脑后动脉、基底动脉。各动脉间CGRP能神经纤维密度比较具有统计学意义 (P <0 .0 1) ,成年鼠脑底动脉壁CGRP能神经纤维以环行分布为主 ;老年鼠脑底动脉壁CGRP能神经纤维密度以大脑前动脉最高 ,走行方式以网状分布为主 ;老年鼠脑底各主要动脉壁CGRP能神经纤维分布密度低于成年鼠相应脑底动脉。结论 不同脑底动脉CGRP能神经纤维分布特征各异 ,老年鼠较成年鼠脑底动脉CGRP能神经纤维的分布密度为低  相似文献   
60.
The HLA-A,B gene frequencies in the world: Migration or selection?   总被引:2,自引:0,他引:2  
Multivariate methods make it possible to condense much of the information available for a large number of alleles into one or a few synthetic variables. The geographic distribution of synthetic variables can be analyzed and plotted by the same technique used in analyzing and mapping the gene frequency of a single allele. The information contained in 21 HLA-A and HLA-B alleles from 116 world populations is condensed in principal components and discriminant functions which describe the global variation of gene frequencies along longitudes and along latitudes.

Most genetic variation is associated with longitude and shows a center of symmetry in Asia. Thus Asia, or some part of it, may have been the center, both geographically and historically of late Pleistocene migrations. However, latitude also plays a significant role (perhaps 10% of the genetic variation). A remarkable symmetry of the latitude variation in opposite (north and south) hemispheres suggests that climatic factors exercise selective pressure for certain HLA alleles. More specifically A1, A3, B7, B8, and B27 show about equally high correlation coefficients (between 0.45 and 0.55) with distance from equator. This results supports the idea that the well-known linkage disequilibria between A1 and B8, A3 and B7 are probably kept by selective pressure.  相似文献   

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