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Matolcsy  A; Inghirami  G; Knowles  DM 《Blood》1994,83(5):1363-1372
Paired samples of chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL) and the subsequent diffuse large cell lymphoma (DLL) of six cases of Richter's syndrome were investigated to establish the clonal relationship between the CLL/SLL and the DLL components and to define the oncogene and/or tumor-suppressor gene alterations involved in the morphologic transformation of CLL/SLL. Southern blot hybridization analysis showed identical clonal immunoglobulin (Ig) gene-rearrangement patterns in the CLL/SLL and DLL components in four cases and different Ig gene-rearrangement patterns in two cases. Polymerase chain reaction (PCR) amplification, cloning, and DNA sequencing of complementary determinant region 3 (CDR3) of the Ig-heavy chain gene of one of the two cases in which the Ig gene- rearrangement patterns were different showed nonidentical sequences in the CLL/SLL and DLL components. In the other case, monomorphic Epstein- Barr virus (EBV) genome integration was detected in the DLL but not in the CLL, suggesting that the CLL and DLL components in this case of Richter's syndrome also represent unrelated clones. Single-strand conformation polymorphism (SSCP) analysis and sequencing of exons 5 through 9 of the p53 tumor-suppressor gene showed a mutation in codon 176 of the DLL but not in the CLL/SLL component in one case where the CLL/SLL and DLL represented different clones. The p53 mutation probably played a role in the development of the lymphoma rather than morphologic transformation of the CLL/SLL in this case. SSCP analysis and sequencing also showed identical mutations in codon 282 in both the CLL/SLL and DLL components in a case where the CLL and DLL represented identical clones. Thus, this p53 gene mutation was present both before and after morphologic transformation, and therefore, probably did not play a primary role in this process. Southern blot hybridization analysis failed to show evidence of bcl-1, bcl-2, c-myc proto-oncogene or retinoblastoma (Rb) tumor-suppressor gene rearrangements in these six cases of Richter's syndrome. In conclusion, the original CLL/SLL and the subsequent DLL in Richter's syndrome may or may not be derived from identical clones, and the well-known proto-oncogenes and tumor- suppressor genes do not appear to play an obvious and consistent role in the morphologic transformation of CLL/SLL to DLL.  相似文献   
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Knotting of intravascular catheters is an uncommon but a well‐recognized occurrence. The Swan–Ganz catheter (SGC) is the one that knots most commonly. A case of a knotted SGC is described in a patient with a persistent left‐sided superior vena cava, and we propose that the presence of a left‐sided superior vena cava is a risk factor for knot formation not previously reported. We review the published work on the risk factors for knot formation and on the techniques used to remove knotted SGC. We describe a technique using a gooseneck snare and Omni Flush catheter (Angiodynamics, Queensbury, NY, USA) to loosen and untie a knotted SGC.  相似文献   
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Evidence-Based Medicine and Psychiatric Practice   总被引:4,自引:0,他引:4  
Evidence-based medicine (EBM) has been defined as the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients. EBM requires the ability to apply a knowledge of medical informatics (e.g., efficiently searching the medical literature) and clinical epidemiology (e.g., being able to critically appraise the literature) to the treatment of individual patients. This article provides an introduction to the history, philosophy, and methods of EBM as applied to psychiatric practice. The article summarizes the five-step EBM model: (1) formulate the question; (2) search for answers; (3) appraise the evidence; (4) apply the results; and (5) assess the outcome. Resources (including Web sites) for further learning are provided.  相似文献   
98.
Bile leaks occur in up to 27 per cent of liver transplant patients after biliary reconstruction. Synthetic sealants have not been investigated for these biliary procedures. We performed a randomized controlled study to evaluate a novel absorbable polyethylene glycol/collagen biopolymer sealant (CT3 Surgical Sealant) after incomplete end-to-end choledochocholedochostomy (CDCD) in pigs. Pigs (n = 18) underwent transection of the common bile duct and incomplete CDCD over a T-tube, leaving a one-sixth circumferential defect anteriorly. Animals were randomly assigned to treatment (CDCD with sealant, n = 9) or control (no sealant, n = 9). Drains were used to monitor leak volume and bilirubin (bili) concentration. Cholangiography was performed on postoperative day 3. Leaks were defined as drain bili/serum bill > 3, total drain output > 10 mL/kg, and/or extravasation on cholangiography. Animals sacrificed at 3 and 8 weeks (n = 4 and n = 5 from each group, respectively) underwent pathologic examination of the CDCD site. Statistical methods included Student's t test, chi2, linear regression, and analysis of variance procedures. The control group had a higher drain output rate over the first 4 postoperative days than the treatment group (P < 0.05, analysis of variance). Five of nine (56%) control and one of nine (11%) treatment animals had a bile leak (P < 0.05, chi2). There was no major inflammatory response to the sealant versus controls. We conclude that CT3 is effective in decreasing biliary leaks in an incomplete CDCD porcine model with no major adverse pathologic changes. This sealant should be considered for trials for biliary reconstruction in humans.  相似文献   
99.
膦甲酸钠治疗疱疹病毒相关性进展性卒中26例   总被引:1,自引:0,他引:1  
李冬梅  高玉林  王永祥 《医学争鸣》2005,26(14):1267-1267
1临床资料我院神经内科200112/200203应用膦甲酸钠(PFA,foscarnetsodium)治疗进展性卒中(progressivestroke,PS)患者26例.男12例,女14例,年龄35~70(平均57±14)岁.总病程19~72d.有高血压病史19例,有短暂性脑缺血发作病史11例,有脑梗死病史3例,有冠心病病史1例.标准符合1995年第四届全国脑血管病会议脑梗死诊断标准[1],并经脑CT或MRI证实为脑梗死;发病后1wk内病情逐步或阶梯样加重,临床常规治疗不能阻止病情进展,按1995年第四届全国脑血管病会议神经功能缺损评分标准[2]评分增加2分(包括2分)以上.采用金标免疫斑点法检测患者血清中人巨…  相似文献   
100.
Optic nerve head swelling is caused by either ocular or systemic diseases of inflammatory, infective, infiltrative, compressive, or ischemic origin. Uncommonly, an isolated optic nerve head swelling without the above underlying mechanisms might also occur. Two patients presented with unilateral, isolated optic nerve head swelling. A detailed oculoneurological examination and a series of investigations failed to indicate any pathology. No probable cause for optic nerve head swelling in these patients was determined by the authors. the authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or privider of services discussed in this article. The authors also do not discuss the use of off-label products, which include unlabeled, unapproved, or investigative products or devices.  相似文献   
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