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81.
We present the case of a 67-year-old male with primary extramedullary leukemia of the prostate gland, the first reported case in the literature to the best of our knowledge. His initial symptoms consisted of episodes of urinary retention. He underwent transurethral resection of the prostate, and a diagnosis of high-grade lymphoma was rendered. He then received a course of doxorubicin-based lymphoma chemotherapy regimen. However, based on a panel of immunocytochemical stains, a diagnosis of extramedullary leukemia or chloroma was confirmed. His bone-marrow examination at this point was normal. He underwent radiation therapy to the prostate with a total dose of 3960 cGy. Seven months after his initial presentation, he progressed to acute nonlymphocytic leukemia (ANLL), M2 by FAB classification. He was successfully treated with induction and consolidation chemotherapy with Ara-C and idarubicin, and was maintained in complete remission up to 19 months of follow-up. Eight other cases of prostatic leukemia reported in the literature are presented. Five cases occurred in association with ANLL, 2 cases as sites of ANLL relapse, and 1 case in association with myelodysplasia. The use of immunohistochemical stains has aided us in diagnosis of extramedullary leukemia. Surgery, radiation therapy, and chemotherapy play complementary roles in the treatment of prostatic extramedullary leukemia. © 1996 Wiley-Liss, Inc.  相似文献   
82.
The DR1 and DRw10β1, chain genes were isolated from each of 2 individuals with rheumatoid arthritis who were heterozygous for these class II major histocompatibility complex specificities. The sequences of the DR1β1 chains from both patients were identical, differing from previously reported DRβ1 chains of individuals without RA by 2 amino acid substitutions, at positions 85 (Val-Ala) and 86 (Gly-Val), and by a silent mutation at the last nucleotide of codon 78 (C–T), resulting in the loss of a Pst I restriction endonuclease site. Identical DRw10β1, chain genes were found in both patients. These were shown to encode the epitope recognized by monoclonal antibody 109d6. This antibody also recognizes an epitope on the DRw53β2 chain of the DR4 haplotype. The third diversity regions of the DR1β (amino acids 67–74) and the DRw10β1 chains (amino acids 67–73) were identical, respectively, with those of the DR4 (Dw14) β1, and β2 chains, raising the possibility that in these patients, the third diversity regions of the two DRβ1, chain genes present in trans are conformationally equivalent to the cis-encoded third diversity regions of the DR4 (Dw14), DRβ1, and β2 chains. The nucleotide sequences of the DQβ complementary DNA clones were identical to that of the DQw1β chain, and no DRβ2 complementary DNA clones were identified.  相似文献   
83.
牙列缺损的计算机三维建模   总被引:4,自引:5,他引:4  
目的 建立牙列缺损的计算机三维模型。方法 采用表面绘制法,依据CT扫描头颅骨标本获得的二维断层图像数据在3D Studio Max中沿牙体长轴放样、微调并赋以材质,得到牙列缺损的计算机三维模型。结果 能在计算机中方便快速地模拟任意类型的牙列缺损,并可全方位地旋转、放大和缩小。结论 提供了一种牙列缺损三维建模的新方法,有利于三维义齿专家系统的开发和计算机辅助教学。  相似文献   
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目的探讨经关节入路微创钢板固定(MIPPO)技术治疗股骨远端C型骨折的临床疗效。方法2002年4月~2005年2月,应用MIPPO技术治疗股骨远端C型骨折14例,按AO/ASIF分类:C1型3例,C2型6例,C3型5例。先行关节内骨折切开复位、松质骨螺钉固定,再行髁上部分骨折间接复位、经关节内切口插入髁支撑钢板或LISS钢板桥接固定骨折。结果12例患者获得10~32个月(平均18.4个月)随访,骨折均获愈合,愈合时间10周~12个月,平均4.6个月。按Kolmert和Wulff的评价标准:优4例,良5例,可2例,差1例,优良率为75%。结论应用MIPPO技术治疗股骨远端C型骨折实现了微创操作,具有创伤小、软组织干扰少、骨折愈合快等优点,疗效满意。  相似文献   
87.
A wealth of evidence has now demonstrated that the microenvironment in which a tumorigenic cell evolves is as critical to its evolution as the genetic mutations it accrues. However, there is still relatively little known about how signals from the microenvironment contribute to the early events in the progression to malignancy. To address this question, we used a premalignant mammary model to examine how fibroblasts, and the extracellular matrix (ECM) proteins they secrete, influence progression to malignancy. Their effect on metastatic malignant cells was also assessed for comparison. We found that carcinoma-associated fibroblasts, and the distinct aligned ECM they deposit, can cause both premalignant and malignant mammary epithelial cells to assume a mesenchymal morphology that is associated with increased dissemination and metastasis, while benign reduction mammoplasty fibroblasts favor the maintenance of an epithelial morphology and constrain early dissemination, tumor growth, and metastasis. Our results suggest that normalizing the organization of the ECM could be effective in limiting systemic dissemination and tumor growth.  相似文献   
88.
Porphyria cutanea tarda (PCT) arises from decreased hepatic activity of uroporphyrinogen decarboxylase (UROD). Both genetic and environmental factors interplay in the precipitation of clinically overt PCT, but these factors may vary between different geographic areas. Decreased activity of UROD in erythrocytes was used to identify patients with UROD mutations among a group of 130 Spanish PCT patients. Nineteen patients (14.6%) were found to harbor a mutation in the UROD gene. Eight mutations were novel: M1I, 5del10, A22V, D79N, F84I, Q116X, T141I and Y182C. Five others were previously described: F46L, V134Q, R142Q, P150L and E218G. The new missense mutations and P150L were expressed in Escherichia coli. D79N and P150L resulted in proteins that were localized to inclusion bodies. The other mutations produced recombinant proteins that were purified and showed reduced activity (range: 2.3–73.2% of wild type). These single amino acid changes were predicted to produce complex structural alterations and/or reduced stability of the enzyme. Screening of relatives of the probands showed that 37.5% of mutation carriers demonstrated increased urinary porphyrins. This study emphasizes the role of UROD mutations as a strong risk factor for PCT even in areas where environmental factors (hepatitis C virus) have been shown to be highly associated with the disease.  相似文献   
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A patient presented to a district general hospital with a type B dissection of the aorta. He was deemed too unwell for surgical intervention. An endovascular stent repair was successfully carried out. The case shows that such a procedure can be safely performed by a multidisciplinary team within a district general hospital.  相似文献   
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