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31.
可切除原发性十二指肠恶性肿瘤X线征象分析   总被引:2,自引:0,他引:2  
目的 :对可切除的原发性十二指肠恶性肿瘤X线征象进行分析。方法 :对 2 6例原发性十二指肠恶性肿瘤胃肠道造影及CT征象进行了回顾性对比分析总结。结果 :全部病例均经手术病理证实 ,其中腺癌 2 2例 ,平滑肌肉瘤 3例 ,非何杰金氏淋巴瘤 1例。描述包括肿瘤的部位 ,造影X线表现 (黏膜破坏 ,充盈缺损及龛影 ,管腔不规则狭窄 ,肠腔外改变等 )及CT表现 (肠壁增厚肠腔狭窄 ,局部肿块 ,梗阻性改变及转移 )。不能手术切除的影像学征象为 :肿瘤直径大于 6cm ;腹腔、系膜淋巴结成团肿大 ;腔静脉、肠系膜动静脉等重要血管管径被包绕大于 2 / 3时。结论 :CT与X线造影对肿瘤的位置、大小、形态 ,肿瘤的继发征象的术前评价 ,能够提供能否手术切除的重要依据。  相似文献   
32.
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   
33.
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   
34.
为探索天然超氧化物岐化酶(SOD)岐化超氧离子的机理,及用于临床的可能性,我们合成了乳酸、柠檬酸和酒石酸的锰(Ⅱ)配合物作为Mn-SOD的模拟物,用光照法测定了它们的活性,得到了有意义的结果:锰配合物作为Mn-SOD的模拟物,有肯定的活性,其中以乳酸锰配合物活性最高。  相似文献   
35.
From mid-October 1989 to mid-July 1990 all newly admitted residents to Bury Local Authority Residential Homes were comprehensively medically screened. In a series of 100 residents eight had early Parkinson's disease (six of them hitherto undiagnosed). Seven showed evidence of Vitamin C deficiency. Of the seven showing evidence of deficiency, four suffered from early Parkinson's disease. Of the 93 without evidence of Vitamin C deficiency only four had Parkinson's disease. This indicates a significantly higher prevalence of Parkinson's disease in the group with Vitamin C deficiency (P less than 0.001 using Fisher's exact).  相似文献   
36.
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(7αoiodoalyldiprenorphine,即7αoIADPN)。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   
37.
38.
BACKGROUND: Sensitization to house dust mite (HDM) is an important risk factor for the development of asthma and allergic disease in childhood. Higher levels of HDM allergen are linked to increased sensitization to HDM. OBJECTIVE: To study the effect of mite-impermeable mattress encasings and an educational package on the development of allergies in a newborn cohort. METHODS: Six hundred and ninety-six newborns at high risk of developing allergies were enrolled in three European countries (Germany, Austria, UK) in a prospective, randomized, controlled birth-cohort study. Children were randomly assigned to an intervention and control group. Intervention measures included the use of mite-impermeable mattress encasings for the child's bed and a simple educational package on allergen avoidance. The control group received basic information about allergies. Children were followed up at age 6, 12, 18 and 24 months. RESULTS: 80.9% of the children were followed up to the age of 24 months. No difference in the prevalence of sensitization to HDM (control vs. intervention group: 8.4% vs. 6.1%, P=0.33) or the development of symptoms (recurrent wheezing 10.3% vs. 10.7%, nocturnal cough 12.5% vs. 12.5%) or allergic diseases (asthma 3.5% vs. 5.1%, eczema 20.0% vs. 19.6%, rhinitis 28.9% vs. 25.8%) could be found between the control and intervention group. CONCLUSION: In this study, HDM avoidance did not show a protective effect on the development of sensitization to HDM or symptomatic allergy in children at age 24 months.  相似文献   
39.
目的提出对学习策略和教学方式的改进建议。方法测试口腔医学生的场依存/独立认知风格,并用统计学方法分析其与口腔正畸学学习成绩的关系。结果①场独立认知风格是口腔医学专业学生认知风格的主体;②不同性别口腔医学专业学生的场依存/独立认知风格无显著性差异;③学生场依存/独立认知风格与口腔正畸学理论考试成绩有负相关倾向,与口腔正畸学实习操作成绩有正相关倾向。结论学习策略和教学方式因受认知风格的影响而制约学生学习的效果。  相似文献   
40.
The effects of combined use of earthworm extract(912)and HpD-laser on the produc-tion of reactive oxygen and the biosynthesis of DNA in S_(180) tumor cells were studied throughchemiluminescence measurement and[~3H]-TdR incorporation assay.The results showed that as com-pared with the control,the intensity of chemiluminescence emitted by tumor cells treatedsimultaneously with 912 and HpD-laser was enhanced more than ten-folds,while that treated with912 or HpD-laser alone was increased only 2~4 folds.The[~3H]-TdR incorporation into tumorcells of the former group was inhibited upto 74.1%,and that of the latter groups decreased onlyby 42.2% and 40.0%,respectively.In accordance with these biochemical changes,the ultrastructuraldamage of tumor cells of the former,combinedly treated group appeared to be the most serious.This suggests an additive effect of 912 with HpD-laser on tumor cells.In addition,if free radicalscavengers,such as catalase and superoxide dismutase,were added to the reaction systembefore chemiluminescence assay,the luminescent enhancement effect mentioned above was dramaticallyalleviated,implying the presence of O_2~ and H_2O_2 in the system.Therefore,as to the toxic effecton tumor cells,912 and HpD-laser are not only additive in efficiency,but also similar in theunderlying mechanism of action.  相似文献   
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