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81.
Bcl-x rather than Bcl-2 mediates CD40-dependent centrocyte survival in the germinal center 总被引:7,自引:2,他引:7
Both rapid B-cell proliferation and programmed cell death (PCD) occur during the differentiation and selection of B cells within the germinal center. To help elucidate the role of Bcl-x in B-cell antigen selection and PCD within the germinal center, we examined its expression in defined B-cell populations and by immunochemistry of tonsil tissue. Purified B-cell fractions enriched for centrocytes express high amounts of Bcl-x and relatively low amounts of Bcl-2, whereas fractions enriched for centroblasts lack significant levels of both proteins. Consistent with this observation, immunocytochemistry localized Bcl-x within cells scattered throughout the germinal center. Stimulation of tonsil B cells with either CD40 or Staphylococcus aureus Cowan increase bcl-x mRNA and protein levels. Treatment of a cell line with a germinal center phenotype (RAMOS) or the tonsillar B-cell centroblast fraction with CD40 rapidly increased Bcl-x levels and partially rescued B cells from PCD. These data suggest that Bcl-x rather than Bcl-2 may rescue centrocytes during selection in the germinal center. 相似文献
82.
NICHOLAS J TALLEY SK LAM KL GOH KM FOCK 《Journal of gastroenterology and hepatology》1998,13(4):335-353
Dyspepsia is most optimally defined as pain or discomfort centred in the upper abdomen. The symptom complex may be caused by peptic ulcer disease, gastro-oesophageal reflux, or gastric cancer but is most often due to functional (or non-ulcer) dyspepsia. While upper endoscopy is the method of choice to determine the underlying cause of dyspepsia, it is expensive. A more pragmatic approach is needed in the Asia-Pacific region where health services are limited. A detailed treatment algorithm is given for managing patients presenting with new-onset dyspepsia and documented functional dyspepsia after endoscopy, and evidence to support this approach is reviewed. Prompt endoscopy is recommended for patients with alarm features. In patients without alarm features, treatment for 2–4 weeks with an empirical anti-secretory or prokinetic agent, followed by investigation using non-invasive Helicobacter pylori testing and treatment for patients who do not respond or relapse, is recommended. Trials of management strategies are now needed to establish the efficacy and cost-effectiveness of the approaches recommended. 相似文献
83.
Nurdan Papila Topal Altug Cincin Murat Sunbul Kursat Tigen Ibrahim Sari 《The International journal of angiology》2013,22(3):181-184
Published reports demonstrate improved myocardial reperfusion with adjunctive thrombus aspiration in ST-elevation myocardial infarction (STEMI). However, implementation of this procedure without angioplasty or stent implantation is not clear. In this report, we present an octogenarian with inferior STEMI who was treated with thrombus aspiration alone. Another important feature of our case is trapped thrombus material in the guiding catheter during thrombus aspiration. Operators should avoid thrombus re-injection by controlling the system carefully during aspiration procedure. 相似文献
84.
KM Aaberg A-S Eriksson J Ramm-Pettersen KO Nakken 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(12):e557-e560
Aim: The aim of this study was to evaluate the long-term results of resective surgery on children with difficult-to-treat epilepsy in Norway. Methods: In the period 1995–2004, 64 surgical procedures (54 resections and 10 functional hemispherotomies) were performed in 54 children. The children’s medical records were retrospectively reviewed at a minimum of 2 years after surgery. We sent a questionnaire regarding their epilepsy (seizures, usage of antiepileptic drugs) and general functioning (social situation, motor, language, cognition, behavioural or emotional problems, any remedial action) to the children/parents after a mean follow-up period of 7 years. Results: 55.5% of the children were seizure-free. The success rate varied according to the type of surgery. Best results were found after functional hemispherotomies and temporal lobe resections, as nine of 10 (90%) and 10 of 19 (53%) of these patients, respectively, became seizure-free. In addition to a better seizure control, 71% of the children/parents reported of a better cognitive and psychosocial functioning. Conclusion: The results of epilepsy surgery in this paediatric cohort are very edifying, and it is our impression that this treatment option is underused in Norway. 相似文献
85.
亚太地区炎症性肠病处理共识意见(一) 总被引:24,自引:0,他引:24
虽然目前亚太地区尚无炎症性肠病(IBD)的大规模流行病学资料,但一系列研究显示其发病率和患病率呈上升趋势。与西方国家相比仍呈滞后现象。溃疡性结肠炎(UC)的发病率仍较克罗恩病(CD)高。除地域差异外。在一些多民族国家中,IBD尚可见种族差异。亚太地区IBD的遗传背景有异于西方国家。如据报道该地区CD患者未检出NOD2/CARDI5变异。一般而言,该地区IBD患者的临床过程似不如西方国家严重。
亚太地区IBD的诊断存在一些特殊问题。如缺乏IBD诊断金标准。存在多种小肠结肠炎,与IBD临床表现相似,使鉴别诊断特别困难。迄今为止,亚太地区IBD的诊断标准多采用西方国家的诊断标准。诊断必须逐步排除非IBD的小肠结肠炎。确诊应有典型的组织学表现。某些患者需借助随访和诊断性治疗才能确诊。进一步研究IBD发病机制将有助于开发更好的诊断标记物。
亚太地区IBD的治疗亦存在特殊问题。由于诊断困难。IBD患者常未能及时接受适当的药物治疗,但该地区仍广泛采用药物治疗方案。结合西方指南和本地经验可制定类似的处理原则。以利诱导缓解和维持缓解。提倡逐级使用基于病变范围、活动性和严重度的阶梯式治疗方案。对不同病例采用综合性、个体化的方法。随着对IBD发病机制和亚太地区IBD独特性的深入理解。合理、实用的药物治疗指南和应用生物制剂治疗将改善该地区IBD的治疗前景。 相似文献
86.
Kirsi M Talala Taina M Huurre Tiina KM Laatikainen Tuija P Martelin Aini I Ostamo Ritva S Prättälä 《BMC public health》2011,11(1):138
Background
Psychological factors associated with low social status have been proposed as one possible explanation for the socio-economic gradient in health. The aim of this study is to explore whether different indicators of psychological distress contribute to socio-economic differences in cause-specific mortality. 相似文献87.
Human breast lesions: characterization with proton MR spectroscopy 总被引:31,自引:0,他引:31
88.
89.
Clustering of mutations in the biotin-binding region of holocarboxylase synthetase in biotin-responsive multiple carboxylase deficiency 总被引:4,自引:2,他引:2
Dupuis L; Leon-Del-Rio A; Leclerc D; Campeau E; Sweetman L; Saudubray JM; Herman G; Gibson KM; Gravel RA 《Human molecular genetics》1996,5(7):1011-1016
Holocarboxylase synthetase (HCS) catalyses the biotinylation of the four
biotin-dependent carboxylases found in humans. A deficiency in HCS results
in biotin-responsive multiple carboxylase deficiency (MCD). We have
identified six different point mutations in the HCS gene in nine patients
with MCD. Two of the mutations are frequent among the MCD patients
analyzed. Four of the mutations cluster in the putative biotin- binding
domain as deduced from the corresponding Escherichia coli enzyme and
consistent with an explanation for biotin-responsiveness based on altered
affinity for biotin. The two others may define an additional domain
involved in biotin-binding or biotin-mediated stabilization of the protein.
相似文献
90.