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41.
Commonly observed in lymphoid neoplasms, deletions of 6q have been correlated with histologic and clinical subsets of non-Hodgkin's lymphoma (NHL). Our recent analysis of loss of heterozygosity of 6q loci in NHL showed two regions of minimal molecular deletion (RMD), an RMD1 at 6q25-27 and an RMD2 at 6q21-23. To establish correlations between these RMDs and regions of minimal cytogenetic deletions (RCDs) on 6q, and to define associations between RCDs and clinico-pathologic features, we have analyzed chromosome 6 abnormalities in 459 consecutively ascertained, karyotypically abnormal cases of NHL. Among these, 126 (27.5%) cases had structural abnormalities of chromosome 6, of which 94 were deletions. Analysis of these deletions identified three RCDs. An RCD1 encompassing 6q25-27 was seen in 45 intermediate- grade NHL. An RCD2 at 6q21 was observed in 11 high-grade NHL, 9 of which were of the immunoblastic subtype. An RCD3 at 6q23 was noted in 18 low-grade NHL lacking a t(14;18) translocation. Of these 18 cases, 12 were small lymphocytic NHL and, in 2 of these, del(6q) was the sole karyotypic abnormality. In 20 cases of low-grade NHL with t(14;18), the deletions spanned both RCD1 and RCD3. These data suggested the presence of at least 3 tumor suppressor genes on 6q within RCD1, RCD2, and RCD3; they also showed associations between RCDs in 6q and subsets of NHL, including a specific association between a group of well-differentiated lymphoid neoplasms and RCD3. The apparent heterogeneity of breakpoints when all NHLs are considered together explains the inability of previous studies to reliably establish correlations between recurring 6q deletions and histologic and clinical features of NHL.  相似文献   
42.
Two human c-onc genes are located on the long arm of chromosome 8.   总被引:27,自引:12,他引:27       下载免费PDF全文
We have used in situ chromosome hybridization techniques to map the human cellular counterparts (c-onc genes) of the transforming genes of two RNA tumor viruses on human meiotic pachytene and somatic metaphase chromosomes. We find that the human c-mos gene is located on chromosome 8 at a position corresponding to band 8q22 on the somatic map. The human c-myc gene is found on chromosome 8 at position 8q24. These regions on the long arm of chromosome 8 have been previously reported to be involved in specific translocations found in the M-2 subset of acute nonlymphoblastic leukemias. Burkitt lymphoma, and other forms of non-Hodgkin lymphoma, and a familial abnormality that predisposes to renal cell carcinoma. These results suggest that translocations of the human c-mos or c-myc genes may be causally related to neoplastic transformation.  相似文献   
43.
Four new cell lines were established from patients with soft tissue sarcomas. Drug sensitivity as well as genotypic characterization, which may be related to drug sensitivity in these cell lines, was determined. Karyotype, H-ras, c-myc and mutant p53 gene expression, Rb, GI- and S-phase cyclins, E2F and major cyclin/CDK inhibitors such as p16 and p21 and p-glycoprotein were analyzed using cytogenetic, Northern blot and immunological methods. Drug sensitivity was determined using growth inhibition tests. These cell lines differed in their morphology and growth rates, forming colonies in soft agar with a cloning efficiency of 4.3–13.4%, and 3 of the 4 cell lines grew in nude mice. Cytogenetic analysis of cell lines revealed highly aneuploid karyotypes. Deletion and/or translocation of chromosome 17 was seen in HS-16, HS-18 and HS-30 cells, and both copies of chromosome 13 were lost or re-arranged in the HS-18 cell line. Mutant p53 protein was present in all 4 cell lines. HS-18 cells showed no expression of the Rb protein and high levels of expression of E2F, cyclin A, cyclin E and CDK2. HS-16 expressed a higher level of cyclin D than the other 3 cell lines. p21waf1 expression was seen in all cell lines, but p16ink4 was expressed only in HS-30 and HS-42 cell lines. These cell lines were sensitive to taxol and relatively resistant to methotrexate, vinblastine and 5-fluorouracil when compared with the fibrosarcoma cell line HT-1080. These new cell lines should provide a useful model for the study of soft tissue sarcomas and for evaluating new drugs or treatments. © 1996 Wiley-Liss, Inc.  相似文献   
44.
胃、结直肠癌术前区域性动脉化疗几个相关问题   总被引:2,自引:0,他引:2  
胃、结直肠癌根治性切除术复发转移是严重影响术后5 a生存率提高的重要原因.以手术为主综合治疗已成为新的趋势,其中术前区域性动脉化疗(preoperative regional-arterial chemotherapy,PRAC)尤为值得重视.本文介绍了术前PRAC的概念、作用机制和影响区域性动脉化疗疗效的相关因素,并就术前区域性动脉化疗在胃、结直肠癌综合治疗中的评价进行讨论.  相似文献   
45.
目的:比较清开灵与利巴韦林对呼吸道合胞病毒肺炎患儿治疗效果的差异。方法:选择2005-02/2006-04在北京儿童医院分中心治疗的小儿呼吸道合胞病毒肺炎97例,患儿法定监护人知情同意。采用单盲、随机、平行对照试验的原则,按区组随机化方法分为2组,清开灵注射液组49例,利巴韦林组48例。①清开灵注射液组:清开灵注射液静脉滴注加口服中成药。②利巴韦林组:利巴韦林注射液静脉滴注加口服复方愈创木酚磺酸钾口服液。两组疗程均为10d,比较两组患儿的疗效。结果:清开灵注射液组脱落3例,利巴韦林组脱落1例,进入结果分析清开灵注射液组46例,利巴韦林组47例。①清开灵注射液组发热患儿体温恢复正常时间比利巴韦林组短[(2.72±1.86)d,(6.29±2.41)d(P<0.01)]。②清开灵注射液组患儿咳嗽、痰壅、气促症状积分改善方面优于利巴韦林组(P<0.05~0.01)。③清开灵注射液组的呼吸道合胞病毒转阴时间明显优于利巴韦林组。④咳嗽、痰壅、病毒转阴时间、气促均进入Logistic模型,其中前两个症状的回归系数绝对值较大。结论:清开灵注射液治疗小儿呼吸道合胞病毒肺炎在退热、止咳平喘、呼吸道合胞病毒转阴时间等方面均具有明显优势,咳嗽、痰壅这两个症状更能反映清开灵注射液的疗效优于利巴韦林。  相似文献   
46.
BAROREFLEX MECHANISMS IN HYPERTENSION   总被引:2,自引:0,他引:2  
  相似文献   
47.

The role of the community management order (CMO) in the management of mental illness has been associated with controversy. There is uncertainty as to the effectiveness of such involuntary treatment. Review of outcomes of involuntary community treatment has shown varied results, and in the remote areas of Australia the issue becomes more complex, and outcomes more difficult to measure. The Northern Territory's Mental Health Act 2000 has broadened criteria for detention. The decision to impose follow-up and case management on an individual (who may reside in a community several hundred kilometres from an in-patient facility) requires careful consideration of its ethical, professional and psychosocial implications. The trend toward increasing use of mental health legislation in the Northern Territory — particularly for Indigenous people — deserves close scrutiny in order that culturally appropriate and sensitive treatment plans are developed.  相似文献   
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