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111.
Chiang C Jacobsen JC Ernst C Hanscom C Heilbut A Blumenthal I Mills RE Kirby A Lindgren AM Rudiger SR McLaughlan CJ Bawden CS Reid SJ Faull RL Snell RG Hall IM Shen Y Ohsumi TK Borowsky ML Daly MJ Lee C Morton CC MacDonald ME Gusella JF Talkowski ME 《Nature genetics》2012,44(4):390-7, S1
We defined the genetic landscape of balanced chromosomal rearrangements at nucleotide resolution by sequencing 141 breakpoints from cytogenetically interpreted translocations and inversions. We confirm that the recently described phenomenon of 'chromothripsis' (massive chromosomal shattering and reorganization) is not unique to cancer cells but also occurs in the germline, where it can resolve to a relatively balanced state with frequent inversions. We detected a high incidence of complex rearrangements (19.2%) and substantially less reliance on microhomology (31%) than previously observed in benign copy-number variants (CNVs). We compared these results to experimentally generated DNA breakage-repair by sequencing seven transgenic animals, revealing extensive rearrangement of the transgene and host genome with similar complexity to human germline alterations. Inversion was the most common rearrangement, suggesting that a combined mechanism involving template switching and non-homologous repair mediates the formation of balanced complex rearrangements that are viable, stably replicated and transmitted unaltered to subsequent generations. 相似文献
112.
113.
WenKun Bai ShaoLing Yang E. Shen JiZhen Zhang ZhiYong Shen Bing Hu 《科学通报(英文版)》2013,58(28-29):3535-3540
The objective of the present study was to investigate whether ultrasound combined with microbubbles induces apoptotic cell death in androgen-independent prostate cancer cells and to identify the probable mechanism. We used ultrasound in continuous wave mode with a frequency of 21 kHz and a spatial-average temporal-average intensity of 46 mW/cm2. Ultrasound combined with microbubbles (200 μL SonoVue?) was used to treat androgen-independent human prostate cancer PC-3 cells for 30 s. PC-3 cells were divided into three groups: the control group, the ultrasound group and the ultrasound combined with microbubbles group. Immediately after treatment, trypan blue exclusion was used to assess cell viability. Cell apoptosis at 24 h after treatment was measured using transmission electron microscopy and flow cytometry. Western blotting was used to evaluate the expression of the apoptosis-related proteins, Bcl-2 and Bax. Ultrasound combined with microbubbles had a minimal effect on the viability of PC-3 cells and induced minimal levels of cell lysis. The level of apoptosis in PC-3 cells induced by this modality was significantly higher than in controls (12.77 ± 0.31% vs. 2.56 ± 0.22%, P<0.01). Treatment with ultrasound combined with microbubbles increased the expression of Bax, a pro-apoptotic protein, and decreased the expression of Bcl-2, an anti-apoptotic protein. It was concluded that ultrasound combined with microbubbles induces apoptotic cell death in human prostate cancer PC-3 cells through down-regulation of Bcl-2 and up-regulation of Bax. 相似文献
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115.
ZG35CrMnSiRe铸钢经不同的热处理,对其强度、硬度、塑性和冲击韧性等机械性能进行测定,实验结果表明其综合机械性能良好。 相似文献
116.
Cloning of a representative genomic library of the human X chromosome after sorting by flow cytometry 总被引:54,自引:0,他引:54
A library of 50,000 recombinants representative of the human X chromosome has been constructed. Human X chromosomes were physically separated using a fluorescence-activated cell sorter. The DNA was purified from the chromosomes, digested to completion with the restriction enzyme EcoRI and cloned into the phage lambda gtWES.lambda B. The X-derived nature of the recombinants was confirmed by hybridization to rodent/human cell line DNA containing only the human X chromosome. Such libraries will be particularly useful for the investigation of genetic diseases such as Duchenne muscular dystrophy, where the basic defect has not been elucidated, and of neoplasia, where several specific chromosomal anomalies, particularly for the leukaemias, have been identified. 相似文献
117.
锌精馏铅塔燃烧室热工问题诊断 总被引:1,自引:2,他引:1
针对韶关冶炼厂锌精馏过程中1号铅塔燃烧室内存在上、下空间温差较大,第2层空气助燃作用很小,第3层空气基本上失去助燃作用等问题,对铅塔燃烧室进行了热工测试.发现铅塔燃烧室内水平方向的温度并非均匀,而且其温差比上、下方向的温差更大.通过对铅塔燃烧室热工诊断及研究,得出导致铅塔燃烧室内烟气与塔盘外壁在水平和上、下方向温差大的原因是燃烧室内煤气、空气以及烟气在各喷口的分布,燃烧室和换热室间隔墙具有保温作用,燃烧室内烟气扰动,直升烟道对第2层煤气和第2,3层空气加热.其中,直升烟道对第2,3层空气的加热作用以及它们较大的沿程阻力导致第2层空气助燃作用小,第3层空气基本上失去助燃作用.这种诊断结果有利于铅塔燃烧室的正常运行和维护. 相似文献
118.
119.
Simulated and reconstructed winter temperature in the eastern China during the last millennium 总被引:7,自引:2,他引:7
LIU Jian H. Storch CHEN Xing E. Zorita ZHENG Jingyun WANG Sumin 《科学通报(英文版)》2005,50(24):2872-2877
Since the 1990s, under the auspicious impetus of two international research programs, the “Past Global Changes” (PAGES) and the “Climate Variability and Pre- dictability” (CLIVAR), massive research work has been carried out on climate and environment changes over the past 2000 years[1-3]. But majority of the studies has been centered on obtaining various kinds of climatic proxy data (such as historical documents, tree rings, ice cores, lake cores) and focused on the reconstruction of… 相似文献
120.
The genome sequence of the rice blast fungus Magnaporthe grisea 总被引:8,自引:0,他引:8
Dean RA Talbot NJ Ebbole DJ Farman ML Mitchell TK Orbach MJ Thon M Kulkarni R Xu JR Pan H Read ND Lee YH Carbone I Brown D Oh YY Donofrio N Jeong JS Soanes DM Djonovic S Kolomiets E Rehmeyer C Li W Harding M Kim S Lebrun MH Bohnert H Coughlan S Butler J Calvo S Ma LJ Nicol R Purcell S Nusbaum C Galagan JE Birren BW 《Nature》2005,434(7036):980-986
Magnaporthe grisea is the most destructive pathogen of rice worldwide and the principal model organism for elucidating the molecular basis of fungal disease of plants. Here, we report the draft sequence of the M. grisea genome. Analysis of the gene set provides an insight into the adaptations required by a fungus to cause disease. The genome encodes a large and diverse set of secreted proteins, including those defined by unusual carbohydrate-binding domains. This fungus also possesses an expanded family of G-protein-coupled receptors, several new virulence-associated genes and large suites of enzymes involved in secondary metabolism. Consistent with a role in fungal pathogenesis, the expression of several of these genes is upregulated during the early stages of infection-related development. The M. grisea genome has been subject to invasion and proliferation of active transposable elements, reflecting the clonal nature of this fungus imposed by widespread rice cultivation. 相似文献