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31.
Andrulis IL Anton-Culver H Beck J Bove B Boyd J Buys S Godwin AK Hopper JL Li F Neuhausen SL Ozcelik H Peel D Santella RM Southey MC van Orsouw NJ Venter DJ Vijg J Whittemore AS;Cooperative Family Registry for Breast Cancer studies 《Human mutation》2002,20(1):65-73
A number of methods are used for mutational analysis of BRCA1, a large multi-exon gene. A comparison was made of five methods to detect mutations generating premature stop codons that are predicted to result in synthesis of a truncated protein in BRCA1. These included four DNA-based methods: two-dimensional gene scanning (TDGS), denaturing high performance liquid chromatography (DHPLC), enzymatic mutation detection (EMD), and single strand conformation polymorphism analysis (SSCP) and an RNA/DNA-based protein truncation test (PTT) with and without complementary 5' sequencing. DNA and RNA samples isolated from 21 coded lymphoblastoid cell line samples were tested. These specimens had previously been analyzed by direct automated DNA sequencing, considered to be the optimum method for mutation detection. The set of 21 cell lines included 14 samples with 13 unique frameshift or nonsense mutations, three samples with two unique splice site mutations, and four samples without deleterious mutations. The present study focused on the detection of protein-truncating mutations, those that have been reported most often to be disease-causing alterations that segregate with cancer in families. PTT with complementary 5' sequencing correctly identified all 15 deleterious mutations. Not surprisingly, the DNA-based techniques did not detect a deletion of exon 22. EMD and DHPLC identified all of the mutations with the exception of the exon 22 deletion. Two mutations were initially missed by TDGS, but could be detected after slight changes in the test design, and five truncating mutations were missed by SSCP. It will continue to be important to use complementary methods for mutational analysis. 相似文献
32.
构建7q32区域鼻咽癌和正常鼻咽上皮细胞部分基因的表达图谱 总被引:7,自引:2,他引:7
目的构建7q32区域鼻咽癌细胞和组织及原代培养人正常鼻咽上皮细胞的部分基因表达图谱。方法通过差异RT-PCR和Northern杂交的方法检测定位于7q32区域的20个EST在鼻咽癌细胞和鼻咽癌组织及原代培养人正常鼻咽上皮细胞mRNA的表达水平。结果8个EST在鼻咽癌细胞HNE1和原代培养人正常鼻咽上皮细胞中表达量较一致,7个EST在两种细胞中均无表达,3个EST(W72688、H19830、AA130630)在鼻咽癌细胞株中表达上调,而2个EST(AA070437、H90882)在原代培养人鼻咽上皮细胞中表达上调。在13例鼻咽癌活检组织中30.7%(4/13)的AA070437表达下调,77%(10/13)的W72688和77%(10/13)的H19830表达上升。结论构建了7q32区域鼻咽癌细胞和组织及原代培养人正常鼻咽上皮细胞部分基因表达图谱,并初步认为A070437的表达下调和W72688、H19830的过表达与鼻咽癌的发生有关。 相似文献
33.
Evolution of age at menarche and at onset of regular cycling in a large cohort of French women 总被引:1,自引:0,他引:1
Clavel-Chapelon F;EN-EPIC group. European Prospective Investigation into Cancer 《Human reproduction (Oxford, England)》2002,17(1):228-232
BACKGROUND: Early exposure to ovarian hormones is considered to increase breast cancer incidence. The age at which the ovaries become functional is thus important. METHODS: We explored the evolution of age at first menstruation and at onset of regular cycling in 86 031 women participating in the E3N-EPIC cohort study, part of the European Prospective Investigation into Cancer. RESULTS: We observed an increase in mean age at menarche among women born between 1925 and 1930, followed by a steady decrease in the youngest birth cohorts. In contrast, age at onset of regular cycling increased gradually from 1925 onwards. There was thus a steady increase in the interval between age at menarche and at onset of regular cycling, mainly due to an increase in the percentage of women in whom regular cycling started at least 5 years after menarche (from 9.0% among women born in 1925-1929 to 20.8% in those born in 1945-1950). The increase in the interval between menarche and onset of regular cycling was even greater among women with a late menarche. CONCLUSIONS: This increase might be due to a change in dietary intake and/or physical exercise aimed at achieving the slim silhouette desired by the younger generations. 相似文献
34.
35.
Risk of T-cell lymphomas in persons with AIDS 总被引:2,自引:0,他引:2
Biggar RJ Engels EA Frisch M Goedert JJ;AIDS Cancer Match Registry Study Group 《Journal of acquired immune deficiency syndromes (1999)》2001,26(4):371-376
Lymphomas in persons with AIDS are mostly B-cell types, but T-cell lymphomas have also been reported. We examined T-cell lymphoma risk in the 2-year period after AIDS onset by linking 302,834 adults with AIDS to cancer registry data. Of 6,788 cases of non-Hodgkin's lymphoma (NHL) with specified histologies, 96 (1.4%) were T-cell lymphomas. Assessment was based on clinical diagnosis and histology because T-cell marker data were inadequate, but when present, marker data supported the T-cell diagnosis. The relative risk of T-cell lymphoma, estimated by standardized incidence ratio, was 15.0 (95% confidence interval: 10.0--21.7). Risks were increased for all subtypes, including mycosis fungoides, peripheral lymphomas, cutaneous lymphomas, and adult T-cell leukemia/lymphoma (ATLL). HIV-related immunodeficiency could be important, but differences between the population developing AIDS and the general population (e. g., immigration from the Caribbean region for ATLL) might independently increase T-cell lymphoma risk. 相似文献
36.
Looi LM Zubaidah Z Cheah PL Cheong SK Gudum HR Iekhsan O Ikram SI Jamal R Mak JW Othman NH Puteri JN Rosline H Sabariah AR Seow HF Sharifah NA;Working Group on Cancer Diagnosis Research 《The Malaysian journal of pathology》2004,26(1):13-27
Cancer is a major morbidity and mortality concern in Malaysia. Based on National Cancer Registry data, the Malaysian population is estimated to bear a cancer burden of about 40,000 new cases per year, and a cumulative lifetime risk of about 1:4. Cancer research in Malaysia has to consider needs relevant to our population, and resources constraints. Hence, funding bodies prioritise cancers of high prevalence, unique to our community and posing specific clinical problems. Cancer diagnosis is crucial to cancer management. While cancer diagnosis research largely aims at improvements in diagnostic information towards more appropriate therapy, it also impacts upon policy development and other areas of cancer management. The scope of cancer diagnosis upon which this paper is based, and their possible impact on other R&D areas, has been broadly categorized into: (1) identification of aetiological agents and their linkages to the development of precancer and cancer (impact on policy development, cancer prevention and treatment), (2) cancer biology and pathogenesis (impact on cancer prevention, treatment strategies and product development), (3) improvements in accuracy, sensitivity and specificity in cancer detection, monitoring and classification (impact on technology development) and (4) prognostic and predictive parameters (impact on treatment strategies). This paper is based on data collected by the Working Group on Cancer Diagnosis Research for the First National Conference on Cancer Research Coordination in April 2004. Data was collated from the databases of Institutions/Universities where the authors are employed, the Ministry of Science, Technology and Innovation (MOSTI) and targeted survey feedback from key cancer researchers. Under the 7th Malaysia Plan, 76 cancer projects were funded through the Intensified Research in Priority Areas (IRPA) scheme of MOSTI, amounting to almost RM15 million of grant money. 47(61.8%) of these projects were substantially in cancer diagnosis, accounting for 65.6% (RM 9.7 million) of cancer project funds. The 8th Malaysia Plan saw a change in research strategy. The IRPA agency fielded several top-down projects which encouraged a multicentre and multidisciplinary approach. This resulted in larger funding per project i.e. RM32 million for 49 projects. There was also a surge of interest in drug development and natural products. Because of this shift in direction, cancer diagnosis projects constituted only 51% of IRPA-funded cancer projects. Nonetheless funding for cancer diagnosis research has exceeded that of the 7th Malaysia Plan, being RM12.5 million by March 2004. The majority of such research is carried out at the Universities, engaging a large number of young scientists and postgraduate students (51 MSc and 21 PhD). A lot of research findings presented at scientific meetings have not yet been published and there is a glaring shortage of patents and commercialization of research findings (such as creation of test kits). Because diagnosis is very much a part of clinical practice, many researchers felt satisfied and confident that their work will be translated into practice and will significantly improve diagnostic services in Malaysia. National guidelines and consensus development on at least three malignancies i.e. breast cancer, oral cancer and lymphoma, have substantial basis in local R&D work. Problems encountered in research included (1) insufficient funding to realize research objectives, (2) lack of local expertise (most research assistants are inexperienced BSc graduates with no or minimal research experience), (3) inadequate technical support from vendors during equipment failure, (4) inexperienced Institutional development units to assist in product development, (5) lack of venture capital for commercialization of findings, and (6) inadequate incentives to undertake research. Researchers pointed out that plans to promote research should include the establishment of (1) regional and national cancer tissue banks, (2) a National Cancer Research Institute, (3) a dedicated cancer research fund, (4) a registry of cancer researchers, (5) national research coordinators, (6) improved coverage by the National Cancer Registry, (7) more international collaboration, (8) a better career structure for researchers, (9) improved Institutional support for product realization, and (10) better recognition for cancer researchers. 相似文献
37.
抗SARS-CoV抗原的人源Fab段噬菌体抗体库的构建 总被引:6,自引:1,他引:6
目的 :利用抗SARS冠状病毒IgG抗体阳性的SARS康复患者外周血淋巴细胞 ,构建人源Fab段抗体文库。方法 :制备外周血淋巴细胞总RNA ,逆转录成cDNA。以其为模板 ,利用针对家族特异性Ig基因的引物扩增重链Fd段和轻链基因 ,并重组到噬菌粒载体pComb3中 ,将重组噬菌粒载体电转化大肠杆菌XL 1Blue,酶切鉴定抗体库的重组率 ,并测定噬菌体抗体库的库容量。结果 :构建了源于SARS康复患者血清中抗Fab段的抗体文库 ,轻链、重链Fd段基因的重组率分别为91%和 75 % ,库容量为 7.2 3× 10 7。结论 :成功地构建了抗SARS CoV抗原的人源Fab段噬菌体抗体库 相似文献
38.
血清血管内皮生长因子测定在鼻咽癌检测中的意义 总被引:4,自引:2,他引:2
目的:探讨血清血管内皮生长因子能否作为鼻咽癌的肿瘤标志物,并作为鼻咽癌诊断与分期检测的指标。方法:对88例鼻咽癌患者和60例鼻咽颈部良性病变及73例正常人进行血清血管内皮生长因子的定量测定。结果:鼻咽癌患者与鼻咽颈部良性病变、正常人比较和鼻咽癌临床各期比较血清血管内皮生长因子含量有显著性的差异。结论:血清血管内皮生长因子含量测定可作为鼻咽癌的发现诊断和临床分期简便可靠的检测指标。 相似文献
39.
目的探讨乳腺癌的临床特点以及台疗方法的评价.方法收集1989年~1992年共573例完整的病例资料.按治疗方法分为手术组、手术+放疗、手术+化疗、手术+放疗+化疗、非手术组.对病例的一般临床特点及生存率进行统计学分析.结果年龄35岁~55岁者占408例,发病部位外上象限为333例,病理实性癌占375例.不同治疗方法的生存率分5年和10年如下手术组78%、62%,手术+化疗72%、45%,手术+放疗57%、40%,手术+放疗+化疗60%、45%,非手术组35%.结论乳腺癌高发病率年龄组为中年,病变多位于外上象限,病理多为浸润性非特殊性癌.治疗方法仍以手术治疗为首选,适当地配合放、化疗等. 相似文献
40.