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MHC class II (I-A) region control of the IgE antibody repertoire to the ABA-1 allergen of the nematode Ascaris 总被引:4,自引:0,他引:4 下载免费PDF全文
ABA-1 is an approximately 14,000 molecular weight (MW) allergen which is among the most abundant proteins synthesized by the nematode parasite Ascaris. IgG and IgE responses to it are major histocompatibility complex (MHC)-restricted in rodents and have only been found to occur in rats of the RT1u haplotype and mice of the H-2s haplotype. Humans infected with the parasite vary substantially in their immune response to the allergen, but the genetic basis for this unknown. H-2 recombinant mice were used to identify the region within the MHC controlling antibody responses to the allergen. IgG antibody to immunoaffinity purified ABA-1 was assayed by radio-immunoassay and IgE by passive cutaneous anaphylaxis. This showed that the restriction element is the I-A molecule and that there was some evidence for I-E modulation of the level of response. 相似文献
23.
Vijay Tumuluri Graham A. Thomas Ian S. Fraser 《Journal of oral pathology & medicine》2004,33(4):204-208
BACKGROUND: We hypothesise that the density of proliferating cells at the invasive tumour front (ITF) has a positive relationship with prognostic and risk factors in human oral squamous cell carcinoma (SCC). METHODS: Tissues from 47 human oral SCC specimens were collected and stained with a monoclonal antibody directed against the Ki-67 antigen using a horseradish peroxidase based two-step immunostaining method. Counting was performed on two parallel sections at the ITF using an image analyser. The Ki-67 labelling index (LI) was determined by measuring the number of nuclei/mm(2) of epithelium. RESULTS: Our results show that the density of proliferating cells is related to clinical staging, with advanced stage of disease having a significantly higher Ki-67 LI compared with early stage of disease (2111 +/- 905 vs. 1908 +/- 913; P = 0.03). Importantly, this study shows that tumours that have metastasised have a significantly higher Ki-67 LI than tumours where distant metastasis was not detected (3257 +/- 650 vs. 1966 +/- 881; P < 0.0001). CONCLUSIONS: Cell proliferation, as measured by the Ki-67 LI at the ITF, has a positive relationship with clinical staging, tumour thickness, smoking status of the patient and alcohol consumption. Further, we suggest that a multicenter study with a large cohort of patients is indicated to fully elucidate whether cell proliferation at the ITF is directly related to patient survival. 相似文献
24.
Acid phosphatases 总被引:1,自引:0,他引:1
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We describe our results with cervical esophagoesophageal anastomosis. This approach has been used with success in 4 patients. It has the advantage of avoiding esophagectomy in patients with benign disease and allows restoration of esophageal continuity in patients having limited options for esophageal replacement. 相似文献
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Oesophageal dissection after thrombolytic treatment for myocardial infarction. 总被引:1,自引:0,他引:1 下载免费PDF全文
A 62 year old woman admitted with a history suggesting acute myocardial infarction had thrombolytic treatment with anisoylated plasminogen-streptokinase activator complex, which resulted in submucosal haemorrhage in the oesophagus; this caused dissection of the wall of the oesophagus and complete dysphagia. The haematoma resolved spontaneously, leaving behind a diverticulum, with reduced peristalsis and delayed emptying but no obstruction. 相似文献
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Alan G. Fraser Peter T. Buser Jeroen J. Bax Willem R. Dassen Petros Nihoyannopoulos Jürg Schwitter Juhani M. Knuuti Martin Höher Frank Bengel András Szatmári 《European journal of nuclear medicine and molecular imaging》2006,33(8):955-959
Advances in medical imaging now make it possible to investigate any patient with cardiovascular disease using multiple methods which vary widely in their technical requirements, benefits, limitations and costs. The appropriate use of alternative tests requires their integration into joint clinical diagnostic services where experts in all methods collaborate. This statement summarises the principles that should guide developments in cardiovascular diagnostic services.This paper is published simultaneously in the European Heart Journal (2006;27:1750–1753) and in the European Journal of Echocardiography (2006;7:268–273). 相似文献
30.
David Z. Wang 《国际脑血管病杂志》2006,14(4):247-251
未破裂脑动脉瘤的处理存在争议。由于其自然史尚未完全明确,因此最佳的治疗策略也不清楚。目前对未破裂脑动脉瘤处理的共识包括观察、显微手术夹闭和血管内治疗。用于随访已知未破裂脑动脉瘤的方法学也有争议,可能取决于经治医生的偏好。大多数动脉瘤由神经外科医师和介入神经放射科医师处理,但未破裂动脉瘤通常是由神经科医师在对患者进行其他神经系统疾病的筛查时首先发现的。因此,关于何时对患者进行筛查和如何对未破裂动脉瘤采取最佳处理的知识将对其日常医疗实践有直接的影响。未破裂动脉瘤经常导致包括缺血事件、癫和头痛在内的其他神经系统症状,这些症状可能促进更积极的干预治疗。由于缺乏设计完善真正基于人群的研究或随机试验,因此目前的最佳处理必须以现有文献和每例患者当时的具体情况为根据。 相似文献