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21.
Meggetto F; Muller C; Henry S; Selves J; Mariame B; Brousset P; Saati TA; Delsol G 《Blood》1996,87(6):2435-2442
To establish an in vivo model for the study of Hodgkin's disease and Reed-Sternberg (RS) cells, 25 lymph node tissue samples involved by Hodgkin's disease were grafted into severe combined immunodeficiency (SCID) mice. Ten Epstein-Barr virus (EBV)-associated tumors were obtained in SCID mice. EBV-positive tumors growing in SCID mice were correlated with the presence of EBV-positive nonneoplastic B cells in patient tumors (90% v 26.6%; P<.01) and was independent of the EBV status of RS cells. Our results suggested that EBV-positive tumors growing in SCID mice originated from normal EBV-positive small lymphocytes (bystander B lymphocytes). We also compared the characteristics of these tumors with those obtained after transplantation of 15 non-Hodgkin's lymphoma and four reactive lymph nodes. The latent period to observe a growing tumor in SCID mice was similar between the two groups (12.86 +/- 5.59 weeks for Hodgkin's disease v 13.6 +/- 5.36 weeks for non-Hodgkin's lymphoma and reactive lymph nodes). The relatively high number of EBV-positive small lymphocytes detected in Hodgkin's disease and T-cell lymphoma compared with B-cell lymphoma may account for the greater percentage of EBV- positive tumors obtained in SCID mice. Our results show that SCID mice do not provide the growth conditions that are required for in vivo growth of RS cells. We noted in some SCID tumors, the presence of binucleated and/or multinucleated giant cells resembling RS cells. However, the presence of such cells was not restricted to mice grafted with lymph nodes involved by Hodgkin's disease. We postulate that in previous reports, cells resembling RS cells were just binucleated EBV- positive lymphoma blastoid cells rather than actual RS cells. 相似文献
22.
Francine M Ducharme Sharon D Dell Dhenuka Radhakrishnan Roland M Grad Wade TA Watson Connie L Yang Mitchell Zelman 《Paediatrics & child health》2015,20(7):353-361
Asthma often starts before six years of age. However, there remains uncertainty as to when and how a preschool-age child with symptoms suggestive of asthma can be diagnosed with this condition. This delays treatment and contributes to both short- and long-term morbidity. Members of the Canadian Thoracic Society Asthma Clinical Assembly partnered with the Canadian Paediatric Society to develop a joint working group with the mandate to develop a position paper on the diagnosis and management of asthma in preschoolers.In the absence of lung function tests, the diagnosis of asthma should be considered in children one to five years of age with frequent (≥8 days/month) asthma-like symptoms or recurrent (≥2) exacerbations (episodes with asthma-like signs). The diagnosis requires the objective document of signs or convincing parent-reported symptoms of airflow obstruction (improvement in these signs or symptoms with asthma therapy), and no clinical suspicion of an alternative diagnosis. The characteristic feature of airflow obstruction is wheezing, commonly accompanied by difficulty breathing and cough. Reversibility with asthma medications is defined as direct observation of improvement with short-acting ß2-agonists (SABA) (with or without oral corticosteroids) by a trained health care practitioner during an acute exacerbation (preferred method). However, in children with no wheezing (or other signs of airflow obstruction) on presentation, reversibility may be determined by convincing parental report of a symptomatic response to a three-month therapeutic trial of a medium dose of inhaled corticosteroids with as-needed SABA (alternative method), or as-needed SABA alone (weaker alternative method). The authors provide key messages regarding in whom to consider the diagnosis, terms to be abandoned, when to refer to an asthma specialist and the initial management strategy. Finally, dissemination plans and priority areas for research are identified. 相似文献
23.
We have previously reported that lithium chloride (LiCl) stimulates the production of granulocyte-macrophage colony-forming cells (GM-CFC), pluripotent stem cells (CFU-S), and differentiated granulocytes, macrophages and megakaryocytes in murine Dexter marrow cultures and that this effect appears to be mediated indirectly by a radioresistant adherent marrow cell. In this study we have established that exposure of murine Dexter cultures to LiCl (4 mEq/L) causes an increase of colony-forming cell megakaryocytes (CFU-meg) over 1 to 6 weeks of culture in both supernatant (188% to 611%) and stromal phases (123% to 246%). Moreover, we have shown that lithium treatment of either irradiated (1,100 rad) or unirradiated stromal cells increased production of activities stimulating formation of megakaryocyte, granulocyte, macrophage, and mixed lineage colonies and proliferation of the factor-dependent cell line, FDC-P1. This FDC-P1 stimulatory activity was completely blocked by an antibody to purified recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF). The baseline or lithium-induced--stromal-derived bone marrow colony stimulating activity was partially blocked by the antibody to rGM-CSF and by an antibody to purified colony stimulating factor I (CSF-1); the two antibodies combined resulted in greater than 90% inhibition of the lithium-induced marrow stimulatory activity. In addition, radioimmunoassay (RIA) showed that although CSF-1 was detectable in supernatants of these cultures, exposure to lithium did not increase CSF-1 levels. These data indicate that Dexter stromal cells produce CSF- 1 and GM-CSF and that lithium appears to exert its stimulatory effects on in vitro myelopoiesis by inducing production of GM-CSF. 相似文献
24.
目的探讨急性阑尾炎多层螺旋CT征象与血清炎性标志物的关系。方法收集2012年1月至2013年12月于同济大学附属杨浦医院经手术病理证实的具有完整临床及影像资料的急性阑尾炎患者66例,对所有患者的急性阑尾病变程度行CT分级,分析其与患者白细胞(WBC)计数、中性粒细胞百分比(NEUT%)及血清C反应蛋白(CRP)水平的相关性。结果急性阑尾炎CT分级与患者WBC计数与CRP水平呈正相关(P0.05),穿孔性阑尾炎患者NEUT%及CRP水平明显高于其他患者。CRP水平与阑尾直径、阑尾积液、回盲部变化、阑尾周围炎性条纹、小肠积液呈正相关(P0.05),WBC计数与回盲部变化及阑尾周围炎性条纹呈正相关(P0.05)。结论WBC计数及CRP水平与急性阑尾炎CT分级有关,CRP对急性阑尾炎的诊断及其严重程度的判断更有优势;CRP、NEUT%是穿孔性阑尾炎的重要预测因子,WBC可以更好地发现早期阑尾周围的炎性反应,综合分析CT表现与血清炎性标志物能更准确地诊断急性阑尾炎。 相似文献
25.
目的研制可注射α-CSH-nano-HA/PHBV-PEG顺铂释药系统,为骨转移瘤提供新型的局部药物缓释系统。方法α-CSH-nano-HA/PHBV-PEG载顺铂制成可注射用α-CSH-nano-HA/PHBV-PEG cis-platinum缓释微球,研究其结构、释药特性、可注射性以及力学性能。结果(1)第1、3、5、7天缓释微球的释药浓度分别为97.5、90.7、83.2、68.5μg/mL,第7天后趋于稳定。(2)可注射α-CSH-nano-HA/PHBV-PEG顺铂释药系统在液固比为0.7时可注射性强,与此同时缓释药系统随着液固比的增大凝固时间延长。结论α-CSH-nano-HA/PHBVPEG顺铂释药系统具有良好的注射性能和缓释作用。 相似文献
26.
目的 评估定量三维彩色能量多普勒超声(three-dimensional color power Doppler ultrasound,3D-CPD)联合β-HCG检查对胎盘功能低下的诊断价值.方法 选择2012年5月至2014年3月在昆明医科大学第四附属医院接受产检的产妇368例,利用GE公司E8三维超声系统对胎盘的血管化指数(VI)、血流指数(FI)和血管化-血流指数(VFI)进行测量,同时利用化学发光法测定β-HCG水平.并存产后记录新生儿体长、体重和生命体征综合评分(Apgar评分).结果 产后共有58例新生儿体重<2 500 g,为观察组,另外3 10例新生儿体重>2 500 g,为对照组.对照组VI、FI和VFI分别为(12.5±5.6)、(47.2±3.3)和(9.0±2.6),观察组为(10.2±4.8)、(40.6±4.1)和(4.2±1.7),差异具有统计学意义(P<0.05);观察组β-HCG水平为(29453.0±229.5) mIU/mL,中位数≥2.5 mom,对照组β-HCG水平为(8 442.6±47.2) mIU/mL,中位数<2.5mom,观察组β-HCG水平明显高于对照组(P<0.05);新生儿基本情况相比,观察组新生儿体长、体重和Apgar评分明显低于对照组(P<0.05).结论 3D-CPD联合β-HCG检查对胎盘功能异常具有重要的诊断价值,有利于围产期了解胎盘功能及估计胎儿预后. 相似文献
27.
28.
美国食品和药物管理局(Food and Drug Administration,FDA)经过多年发展和改革,已形成了成熟的上市前监管体系。本文通过对FDA上市批准路径(上市前批准、上市前通告、人道主义用器械豁免)和申报流程进行系统介绍,总结了加强事前沟通、降低产品风险等级和设立实质审查程序三个方面的启示,希望我国监管机构能充分吸收美国FDA对于医疗器械监管的经验和教训,建立适合中国国情的医疗器械监管体系,确保公众用器械安全。 相似文献
30.
目的 探讨骨质疏松症中医体质与辨证分型之间的相关性。方法 按照中西医诊断标准,将确诊的骨质疏松症患者进行中医体质分类与中医辨证分型的临床研究,找出其相关性与规律性,并进行总结。 结果 对300例患者进行中医辨证分型发现脾胃气虚证最多,占总病例数的23.00%,其次为肝肾不足证,占22.00%,以后依次为肾阳虚证、肾阴虚证、气血不足证、血瘀证、骨痿证、肝气郁结证、痰湿证、湿热证;在9种体质分类中阴虚质发病率排在第一位,其次为气虚质,以后依次为阳虚质、血瘀质、特禀质、平和质、痰湿质、湿热质与气郁质。结论 提示9种中医体质中阴虚质与气虚质发病率较高, 辨证分型中发病率较高的2个证型是脾胃气虚型与肝肾阴虚型。说明了体质类型与OP发病率有密切的相关性。 相似文献