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11.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma   总被引:6,自引:3,他引:6  
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.  相似文献   
12.
Lymphangiomas in children: MR imaging   总被引:9,自引:0,他引:9  
Seventeen lymphangiomas in 15 patients were imaged with magnetic resonance (MR) to define the nature, extent, and anatomic relationships of these lesions. The MR and pathologic findings were then compared to determine the histologic basis for the signal-intensity characteristics of these lesions. The signal intensity of 13 lesions was similar to or slightly less than that of muscle on T1-weighted images and greater than that of fat on T2-weighted images. This appearance correlated with the presence of ectatic lymphatic channels containing clear fluid on histologic section. Four lymphangiomas had high signal intensity, approximately equal to that of fat, on T1-weighted images, reflecting the presence of clotted blood or small cystic spaces with a higher ratio of fat to fluid. Sixteen of 17 lesions had visible septations on MR images. The authors' experience suggests that most lymphangiomas have a characteristic appearance on MR images. The information obtained with MR imaging can help in providing a preoperative diagnosis, in planning surgical resection, and in defining recurrence.  相似文献   
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15.

Purpose

Variation exists in the surgical methods employed for decompression of Chiari II malformation (CIIM), yet an evaluation of these techniques has not been performed. The purpose of this study was to assess the efficacy of bony decompression (cervical laminectomy alone versus suboccipital craniectomy with laminectomy) with or without dural augmentation for the treatment of symptomatic CIIM.

Methods

Clinical records of children 0–18 years of age who underwent surgical repair of myelomeningocele or CIIM decompression at St. Louis Children’s Hospital (SLCH) from 1990–2011 were reviewed. Signs/symptoms prompting decompression, surgical technique, operative parameters, and clinical outcomes were recorded for analysis.

Results

Thirty-three subjects were treated at SLCH for CIIM decompression. Twenty-six subjects underwent bony decompression only (21 cervical laminectomy alone, 5 suboccipital craniectomy?+?cervical laminectomy) while seven underwent bony decompression with upfront dural augmentation (three cervical laminectomy alone, four suboccipital craniectomy?+?cervical laminectomy). Median follow up was 5.0 years (range, 3 months–19 years). Symptomatic improvement was noted in 20/33 subjects (60.6 %). Sixty-two (61.5 %) percent of children who underwent bony decompression had symptomatic improvement, compared with 57.1 % of those with upfront dural augmentation (p?=?0.37). Estimated blood loss, operative time, and length of perioperative hospital stay appeared lower in the bony decompression group but were not statistically different in this limited cohort.

Conclusions

The results from this series suggest that bony CIIM decompression via tailored cervical laminectomies alone, without suboccipital craniectomy or upfront dural augmentation, is a reasonable initial management approach for decompression of symptomatic CIIM.  相似文献   
16.
Sporn  LA; Marder  VJ; Wagner  DD 《Blood》1987,69(5):1531-1534
Large multimers of von Willebrand factor (vWf) are released from the Weibel-Palade bodies of cultured endothelial cells following treatment with a secretagogue (Sporn et al, Cell 46:185, 1986). These multimers were shown by immunofluorescent staining to bind more extensively to the extracellular matrix of human foreskin fibroblasts than constitutively secreted vWf, which is composed predominantly of dimeric molecules. Increased binding of A23187-released vWf was not due to another component present in the releasate, since releasate from which vWf was adsorbed, when added together with constitutively secreted vWf, did not promote binding. When iodinated plasma vWf was overlaid onto the fibroblasts, the large forms bound preferentially to the matrix. These results indicated that the enhanced binding of the vWf released from the Weibel-Palade bodies was likely due to its large multimeric size. It appears that multivalency is an important component of vWf interaction with the extracellular matrix, just as has been shown for vWf interaction with platelets. The pool of vWf contained within the Weibel-Palade bodies, therefore, is not only especially suited for platelet binding, but also for interaction with the extracellular matrix.  相似文献   
17.
Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra.  相似文献   
18.
软骨修复组织蛋白多糖代谢与一氧化氮合酶抑制剂的影响   总被引:3,自引:0,他引:3  
目的:应用一氧化氮合酶抑制剂可改善骨性关节炎和风湿性关节炎软骨的代谢,作者前期的实验也证明一氧化氮合酶抑制剂能提高软骨修复组织的质量。实验进一步观察一氧化氮合酶抑制剂对软骨修复组织蛋白多糖代谢的影响。方法:实验于1999-06/2002-02在南方医科大学完成。①实验分组:取雄性新西兰兔24只,8月龄,体质量(2.5±0.2)kg。随机抽签法分为对照组、骨形态发生蛋白组和S-甲基异硫脲组,每组8只。②实验方法:将大白兔双侧股骨髁间关节面造成全层软骨缺损,对照组:软骨缺损不充填任何物质;骨形态发生蛋白组:缺损用骨形态发生蛋白纤维蛋白凝胶复合物充填;S-甲基异硫脲组:缺损应用胶原复合骨形态发生蛋白充填,术后按5mg/(kg·12h)皮下注射S-甲基异硫脲。术后1年麻醉后处死动物。③实验评估:应用组织切片番红O-快绿染色和图像分析技术,按照染色百分率、平均灰度(平均染色程度)和染色厚度(软骨厚度)指标来检测糖胺聚糖含量;应用Na235SO4掺入法检测软骨修复组织蛋白多糖合成。结果:纳入新西兰兔24只,均进入结果分析。①术后1年,对照组几乎无红色染色区域;骨形态发生蛋白组可见到少量的不均匀红色区域;S-甲基异硫脲组可见到较多均匀一致的红色染色区域。②S-甲基异硫脲组软骨修复组织番红O染色百分率为89.28%,明显高于骨形态发生蛋白组36.54%和对照组13.4%,S-甲基异硫脲组修复组织番红O-快绿染色平均灰度值134.5,分别为骨形态发生蛋白组平均灰度值56.8的2.5倍,为对照组26.4的7倍。软骨平均厚度S-甲基异硫脲组1.75cm分别为骨形态发生蛋白组0.76cm和对照组0.25cm的2倍和6倍。③Na235SO4掺入法结果显示,S-甲基异硫脲组[35S]摄入量明显高于骨形态发生蛋白组和对照组(P<0.01)。结论:诱导型一氧化氮合酶抑制剂S-甲基异硫脲的应用能明显增加软骨修复组织糖胺聚糖含量和蛋白多糖合成,对于软骨修复质量的提高有积极意义。  相似文献   
19.
The CD11b/CD18 leukocyte integrin molecule mediates diverse neutrophil adherence-related functions, including cell:cell and cell:extracellular matrix attachments. To study the individual role of this leukocyte integrin in cell adherence in hematopoietic cells, we expressed the CD11b/CD18 complex on the surface of K562 cells, a cell line derived from an individual with chronic myelogenous leukemia in blast crisis. We used an amphotrophic retroviral vector designated LCD18SN, harboring the complete coding sequence for the CD18 subunit, to transfer the CD18 cDNA into K562 cells and select stable cell lines. The CD11b subunit in the expression plasmid pREP4 was transfected into these K562/CD18 cells by electroporation and stable cell clones were selected. These K562 cells possessed RNA and intracellular protein for each subunit, and they expressed the CD11b/CD18 heterodimer on the cell surface. When CD11b/CD18 expressing K562 cells were stimulated with phorbol myristate acetate (50 ng/mL) for 24 to 48 hours, these K562 cells formed dense cell:cell aggregates. This homotypic aggregation required both activation of the CD11b/CD18 complex and the induction of the counter- receptor for CD11b/CD18 on the conjugate cell. This cell line will (1) enable the structure-function relationships between cell activation and homotypic adherence to be assessed, (2) provide the opportunity to identify accessory molecules required for activation of the CD11b/CD18 complex, and (3) facilitate the identification of novel ligands for the CD11b/CD18 complex.  相似文献   
20.
目的:了解中国不同地区间中老年人群膝关节骨性关节炎患病危险因素。方法:调查时间为2005—07/08。①从中国六大行政区(西北,华北,华东。中南,东北,西南)选出六城市(西安,石家庄,上海。广州,哈尔滨市,成都),用分层多阶段整群抽样方法,抽取6218名40岁及以上具有正式户口常住男女人群进行膝关节骨性关节炎的流行病学问卷调查(包括一般情况、现病史、既往史、体格检查、X射线片检查情况和疾病诊断6个方面,共计94个问题141个变量指标),并对其中4808名有症状者进行X射线平片膝正侧位投照。②膝关节骨性关节炎诊断标准为临床症状阳性加X射线Kellgren & Lawrence分级二级及以上者。③计算患病率,并采用Epilnf06.0和SPSS 10.0软件对其中83个变量进行多因素非条件Logistfc回归分析,表示疾病与暴露因素之间联系强度的指标用比值比(OR),若OR〉1,说明疾病发生危险性增加,与暴露因素呈正关联;若OR〈1,说明疾病发生危险性减少,与暴露因素呈负关联。 结果:①六城市膝关节骨性关节炎总患病率为15.6%,其中西安7.7%,石家庄11.2%,上海9.8%。广州30.5%,哈尔滨16.9%,成都17.5%,各城市患病率比较差异显著(P〈0.01)。②Logistic回归分析膝关节骨性关节炎在大部分城市有共同的危险因素如年龄大(OR=1.032—1.181),使用蹲坑排便年限长(OR=1.021-1.077),体质量高(OR=1.048—1.073),和开始饮酒年龄大(OR=1.008~1.028);而从事专职体育运动(OR=1.651,西安),骨质疏松病史(OR=3.311,石家庄),吸烟(OR=2.654,石家庄),类风湿关节炎病史(OR=4.964,上海),文化程度高(OR=2.593,上海),女性(OR=2.510,广州),姐妹骨关节炎史(OR=13.251,哈尔滨),母亲骨关节炎史(OR=5.683,成都)等危险因素分别在不同地区出现. 结论:年龄大、使用蹲坑排便年限长、体质量高和开始饮酒年龄大是中国六地区膝关节骨性关节炎患病的共同危险因素,同时,不同地区主要危险因素又有一定差异。  相似文献   
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