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排序方式: 共有131条查询结果,搜索用时 31 毫秒
31.
Xie Zongming Lei Gang Wuriyanghan Hada Tian Aiguo Zhang Jinsong Chen Shouyi 《自然科学进展》2007,17(10):1152-1160
Ethylene plays important roles in plant growth, development, and stress responses, and ethylene receptors have been identified and studied extensively in various plant species. Here we report the cloning of four ethylene receptor genes from soybean, i.e. GmETR1, GmERS1, GmETR2 and GmEIN4. Construction of the phylogenic tree showed that GmETR1 and GmERS1 belong to subfamily I whereas GmETR2 and GmEIN4 belong to subfamily II. The four ethylene receptor genes showed different tissue-specific expression patterns in roots, stems, leaves, cotyledons, flowers, pods and seeds of soybean. These genes were differentially regulated by various abiotic stresses and plant hormones. The possible roles of the four genes in soybean plant were also discussed. 相似文献
32.
Therapeutic angiogenesis induced by human hepatocyte growth factor gene in hindlimb ischemia of dogs 总被引:2,自引:0,他引:2
HAXiaoqin RENJianping BIJianjin ZHANGJinhui WUZuze 《科学通报(英文版)》2003,48(7):676-680
A preclinical study of treating peripheral srtery occlusive disease(PAD) was performed by using a hepatocyte growth factor(HGF) gene-expressing vector,plasmid pUDKH,in a dog model with complete ischemia of one hindlimb.After ligation of femoral artery of one hindlimb,pUDKH was transferred directly into the ischemic limb muscles.The angiogenic activity of the plasmid pUDKH was evaluated.On D 30 after injecting once of pUDKH at differ-ent doses into local muscles immediately after operation,the degree of augmentation of collateral vessel formation was significantly greater than that treated by blank vector.In addition,the blood flow rate of femoral artery in dogs treated with pUDKH was recovered on D90,while the folw rate was only 1/5 tp 1/3 in control dogs.The pulse amplitude of pUDKH-treated dogs was recovered on D90,but it was hardly detectable in most of the control dogs.The side effects of intramuscular transfection of pUDKH were also investi-gated,and no significant positive change was found.It is suggested that angiogenesis induced by HGF gene has the potential for clincal use in the treatment of peripheral arte-rial diseases. 相似文献
33.
Tabata S Kaneko T Nakamura Y Kotani H Kato T Asamizu E Miyajima N Sasamoto S Kimura T Hosouchi T Kawashima K Kohara M Matsumoto M Matsuno A Muraki A Nakayama S Nakazaki N Naruo K Okumura S Shinpo S Takeuchi C Wada T Watanabe A Yamada M Yasuda M Sato S de la Bastide M Huang E Spiegel L Gnoj L O'Shaughnessy A Preston R Habermann K Murray J Johnson D Rohlfing T Nelson J Stoneking T Pepin K Spieth J Sekhon M Armstrong J Becker M Belter E Cordum H Cordes M Courtney L Courtney W Dante M Du H 《Nature》2000,408(6814):823-826
The genome of the model plant Arabidopsis thaliana has been sequenced by an international collaboration, The Arabidopsis Genome Initiative. Here we report the complete sequence of chromosome 5. This chromosome is 26 megabases long; it is the second largest Arabidopsis chromosome and represents 21% of the sequenced regions of the genome. The sequence of chromosomes 2 and 4 have been reported previously and that of chromosomes 1 and 3, together with an analysis of the complete genome sequence, are reported in this issue. Analysis of the sequence of chromosome 5 yields further insights into centromere structure and the sequence determinants of heterochromatin condensation. The 5,874 genes encoded on chromosome 5 reveal several new functions in plants, and the patterns of gene organization provide insights into the mechanisms and extent of genome evolution in plants. 相似文献
34.
文章结合公路施工实践,对在湿陷性黄土地区采强夯路基施工新技术.能够很好地解决高等级公路建设中的不良土质和地基的路基施工,并对强夯的施工条件、参数、施工工序、施工要点及检测方法作了介绍. 相似文献
35.
文中介绍了澳大利亚铁矿石漏斗车的主要用途、技术参数、车体结构及其性能特点。此矿石漏斗车采用新技术、新型的设计理念和简单的设计结构将卸车设备与车辆结构结合在一起,节约了生产成本,减缩了生产周期,提高了车辆的使用寿命和运行稳定性,适合于国内外铁路线的运用。 相似文献
36.
求解群体多指标决策问题的偏爱度法 总被引:16,自引:0,他引:16
对于离散的群体多指标决策问题,本文引进方案的优距数和劣距数,利用它们导出并定义了群体关于方案的偏爱度的计算公式和概念.以此为基础,本文给出一个对离散群体多指标决策问题进行排序的有效方法. 相似文献
37.
用VSM-55型振动样品磁强计,对Bi系超导样品在液氮温区80K时进行磁测量,发现磁滞回线在Hc1<≈H<<Hc2范围内是可逆的,据此计算了样品中的(2223)相含量,通过与X-ray衍射分析结果比较得知,此方法非常适合于Bi系(2223)相含量高于80%的样品。 相似文献
38.
哈旭娴 《萍乡高等专科学校学报》2006,(4):82-84
“全球化”已成为当今世界政治、经济、文化等各领域的发展趋势。在此背景下,比较文学作为一门独立的学科,须突破传统的“文本中心”研究方法,向比较文化发展。这不仅是研究方法的转变问题,更是该学科的发展趋势。在比较文学的比较文化发展趋势下,对东西方思维模式的思考也成为我们必须关注的课题之一。在比较文学的研究中,我们应吸收种种思维方式的长处和优点,这样才能有助于我们对问题的观察和分析。 相似文献
39.
Shah SP Roth A Goya R Oloumi A Ha G Zhao Y Turashvili G Ding J Tse K Haffari G Bashashati A Prentice LM Khattra J Burleigh A Yap D Bernard V McPherson A Shumansky K Crisan A Giuliany R Heravi-Moussavi A Rosner J Lai D Birol I Varhol R Tam A Dhalla N Zeng T Ma K Chan SK Griffith M Moradian A Cheng SW Morin GB Watson P Gelmon K Chia S Chin SF Curtis C Rueda OM Pharoah PD Damaraju S Mackey J Hoon K Harkins T Tadigotla V Sigaroudinia M Gascard P Tlsty T Costello JF Meyer IM Eaves CJ Wasserman WW 《Nature》2012,486(7403):395-399
Primary triple-negative breast cancers (TNBCs), a tumour type defined by lack of oestrogen receptor, progesterone receptor and ERBB2 gene amplification, represent approximately 16% of all breast cancers. Here we show in 104 TNBC cases that at the time of diagnosis these cancers exhibit a wide and continuous spectrum of genomic evolution, with some having only a handful of coding somatic aberrations in a few pathways, whereas others contain hundreds of coding somatic mutations. High-throughput RNA sequencing (RNA-seq) revealed that only approximately 36% of mutations are expressed. Using deep re-sequencing measurements of allelic abundance for 2,414 somatic mutations, we determine for the first time-to our knowledge-in an epithelial tumour subtype, the relative abundance of clonal frequencies among cases representative of the population. We show that TNBCs vary widely in their clonal frequencies at the time of diagnosis, with the basal subtype of TNBC showing more variation than non-basal TNBC. Although p53 (also known as TP53), PIK3CA and PTEN somatic mutations seem to be clonally dominant compared to other genes, in some tumours their clonal frequencies are incompatible with founder status. Mutations in cytoskeletal, cell shape and motility proteins occurred at lower clonal frequencies, suggesting that they occurred later during tumour progression. Taken together, our results show that understanding the biology and therapeutic responses of patients with TNBC will require the determination of individual tumour clonal genotypes. 相似文献
40.
The genomic and transcriptomic architecture of 2,000 breast tumours reveals novel subgroups 总被引:1,自引:0,他引:1
Curtis C Shah SP Chin SF Turashvili G Rueda OM Dunning MJ Speed D Lynch AG Samarajiwa S Yuan Y Gräf S Ha G Haffari G Bashashati A Russell R McKinney S;METABRIC Group Langerød A Green A Provenzano E Wishart G Pinder S Watson P Markowetz F Murphy L Ellis I Purushotham A Børresen-Dale AL Brenton JD Tavaré S Caldas C Aparicio S 《Nature》2012,486(7403):346-352