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21.
经逆转录病毒载体将人GM-CSF基因导入人膀胱癌细胞株BIU-87细胞中,建立了转基因细胞株BIU/GM。经流式细胞仪行细胞DNA周期分析表明GM-CSF基因的导人及表达对BIU-87细胞的增长无影响。免疫荧光测定发现转GM-CSF基因及表达不能促进BIU-87细胞表面HLA-ABC、DR、DQ抗原的表达。转基因瘤细胞株经6000rad X射线照射灭活后,丧失增殖能力,逐步死亡,但能维持一定水平的GM-CSF分泌活性达两周以上。从而为制备灭活的转基因瘤苗提供了初步经验。 相似文献
22.
Tsutomu Ogata Peter Goodfellow Christine Petit Pierre Maroteaux Nobutake Matsuo 《American journal of medical genetics. Part A》1993,45(1):101-104
This is a follow-up report on a male patient with a 46, Y, r(X) karyotype. Although he had no clinico-radiological features of X-linked recessive chondrodysplasia punctata (CDPX1), molecular studies revealed an Xp terminal deletion involving the putative region for the CDPX1 locus (PABX-DXS31). We suspect that the absence of CDPX1 may be attributable to the nature of the disease and the extreme short stature of the patient (mean – 5.6 S.D.). © 1993 Wiley-Liss, Inc. 相似文献
23.
目的:探讨人卵巢癌标本中,肿瘤转移抑制基因nm23-H1编码蛋白NDPK-A表达的临床意义及其与预后的关系。方法:应用免疫组织化学抗生蛋白链菌素-过氧化酶结合(S-P)法,检测58例人卵巢癌标本中nm23-H1蛋白水平。结果:nm23-H1蛋白的表达与患者手术时是否有淋巴结及大网膜转移相关(P〈0.05),但原发灶与转移灶间的阳性表达率相差不显著;与患者术后生存时间密切相关(P〈0.01),术后生 相似文献
24.
Emmanuelle Gnin 《Genetic epidemiology》2001,21(Z1):S614-S619
Comparison of polymorphic sites such as single nucleotide polymorphisms (SNPs) within a gene between cases and controls may be useful for establishing a role of this gene in disease susceptibility. The approach includes two steps: the first step is the discovery of the different SNPs within the candidate gene and the second step is the association testing per se that can be done on the entire set of sites discovered or on a subset of these sites only. Selecting a subset of sites may increase the power to detect the association with the candidate gene since a smaller number of tests would then be performed. We proposed a strategy to select sites within a candidate gene and applied it on the Genetic Analysis Workshop 12 candidate gene data. Using these selected sites, we detected an association with candidate genes 1 and 6. © 2001 Wiley‐Liss, Inc. 相似文献
25.
Donna M. Ballantine Shelley A. Klemm Terry J. Tunny Michael Stowasser Richard D. Gordon 《Clinical and experimental pharmacology & physiology》1994,21(3):215-218
1. Aldosterone levels in patients with unilateral aldosterone-producing adenomas may be responsive or unresponsive to the renin-angiotensin system, with the former often previously misdiagnosed as bilateral adrenal hyperplasia. 2. In tumours from patients in the responsive subgroup, renin mRNA is expressed in greater amounts than in tumours from patients in the unresponsive subgroup, or in normal adrenals. 3. We compared the frequency of four renin gene polymorphisms in peripheral blood DNA from the two subgroups and found significant associations between BglI, TaqI and HinfI restriction fragment length polymorphisms (RFLP) and aldosterone responsiveness. 4. Allelic variation in the constitutive renin gene was associated with a specific cause of hypertension. 相似文献
26.
目的:研究中国汉族群体中α艾杜糖苷酶基因D4S111位点的遗传多态性。方法:采用扩增片段长度多态性(AmpFLP)分析技术,检测了广州地区汉族无血缘关系健康个体97名。结果:D4S111位点,在97名无关个体中发现5个等位基因和9种基因型,等位基因片段长度为830~510bp,基因频率为00052~03608,PIC为05966,杂合性为078。结论:中国汉族群体中D4S111位点具有高度多态性,并与其它种族间存在差异性。 相似文献
27.
28.
Immunoglobulin Gene Rearrangement in Plasma Cell Dyscrasias: Detection of Small Clonal Cell Populations in Peripheral Blood and Bone Marrow 总被引:1,自引:0,他引:1
Falko Fend Katharina Weyrer Johannes Drach Andrea Schwaiger Florian Umlauft Kurt Grü newald 《Leukemia & lymphoma》1993,10(3):223-229
The bone marrow (BM) and peripheral blood (PB) samples of 71 patients with plasma cell dyscrasias were analysed by the Southern blot technique for the presence of clonal immunoglobulin (Ig) gene rearrangements. 53% of BM samples examined were archival material such as air dried BM slides or frozen trephine biopsies. The results were related to bone marrow plasmacytosis as determined by cytology and flow cytometry, and other clinical parameters. Clonal Ig gene rearrangements were found in BM samples of 45 (83%) of 54 MM patients and in 3 of 6 patients with monoclonal gammopathy of unknown significance (MGUS). Clonal cell populations in the PB were detected in 11 (30%) of 37 examined MM patients, but in none of the patients with MGUS or solitary plasmacytoma of bone. PB involvement was associated with progressive disease. Circulating monoclonal cells were significantly associated with higher M-protein levels (p 0.05). Thus, circulating clonal precursor cells are encountered more frequently in active MM. 相似文献
29.
梅毒螺旋体外膜蛋白Gpd的基因型分析及其重组蛋白的免疫原性鉴定 总被引:2,自引:0,他引:2
目的 构建梅毒螺旋体 (Treponemapallidum ,Tp)外膜蛋白Gpd基因的原核表达载体 ,检测其表达产物的免疫原性 ,并比较梅毒螺旋体各菌株Gpd基因序列的同源度。方法 从TpNichols株基因组模板中PCR扩增Gpd基因 ,与GenBank登录的序列做blast比较 ,定向克隆构建原核表达重组体pET2 8b( + ) -Gpd ,转入大肠杆菌ril表达菌 ,SDS -PAGE分析重组蛋白的表达 ,Western -blot检测重组蛋白的免疫原性。结果 载体上所连目的基因片段序列与GenBank登录的Nichols株Gpd基因序列完全一致 ,同其他病原性密螺旋体菌株登陆序列比较同源度为 98%~ 1 0 0 %。SDS -PAGE检测诱导产物显示有一Mr约为 41kDa的特异蛋白带 ,免疫印迹技术检测其能与梅毒阳性标准血清反应。结论 Tp原核表达重组体pET2 8b( + ) -Gpd成功构建 ,且能够在ril表达菌中融合表达 ,为进一步研究该蛋白的生物学功能奠定了一定的实验基础。 相似文献
30.
Summary: To develop a method for identification of differential gene expression between different cell populations, several convenient techniques of molecular biology, including subtractive hybridization, suppression PCR, T/A cloning and sequencing, were used to identify genes expressed differentially in CD45^- and CD45^- cells isolated from U266 cell line of multiple myeloma. Our results showed that the levels of abundant genes scale down 20 times through subtractive hybridization.Plasmid DNA from CD45^- cell clones was hybridized with forward or backward cDNA probes synthesized from CD45^- and CD45 cells, respectively. A few of differentially expressed genes reconfirmed by RT-PCR were identified from 500 expressed clones of CD45^- cells. It is concluded that a strategy for gene expression identification developed from conventional molecular biological methods can be used in different laboratories. 相似文献