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排序方式: 共有10000条查询结果,搜索用时 24 毫秒
271.
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
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275.
Integrins and cardiovascular disease 总被引:2,自引:0,他引:2
Cardiovascular diseases involve abnormal cell-cell interactions leading to the development of atherosclerotic plaque, which
when ruptured causes massive platelet activation and thrombus formation. Parts of a loose thrombus may detach to form an embolus,
blocking circulation at a more distant point. The integrins are a family of adhesive cell receptors interacting with adhesive
proteins or with counterreceptors on other cells. There is now solid evidence that the major integrin on platelets, the fibrinogen
receptor α
IIb
β
3 , has an important role in several aspects of cardiovascular diseases and that its regulated inhibition leads to a reduction
in incidence and mortality due to these disorders. The development of α
IIb
β
3 inhibitors is an important strategy of many pharmaceutical companies which foresee a large market for the treatment of acute
conditions in surgery, the symptoms of chronic conditions and, it is hoped, maybe even the successful prophylaxis of these
conditions. Although all the associated problems have not been solved, the undoubted improvements in patient care resulting
from the first of these treatments in the clinic have stimulated further research on the role of integrins on other vascular
cells in these processes and in the search for new inhibitors. Both the development of specific inhibitors and of mice with
specific integrin subunit genes ablated have contributed to a better understanding of the function of integrins in development
of the cardiovascular system. 相似文献
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The role of peroxisomes in aging 总被引:2,自引:0,他引:2
278.
G. M. Rossolini S. Schippa M. L. Riccio F. Berlutti L. E. Macaskie M. C. Thaller 《Cellular and molecular life sciences : CMLS》1998,54(8):833-850
Bacterial nonspecific acid phosphohydrolases (NSAPs) are secreted enzymes, produced as soluble periplasmic proteins or as
membrane-bound lipoproteins, that are usually able to dephosphorylate a broad array of structurally unrelated substrates and
exhibit optimal catalytic activity at acidic to neutral pH values. Bacterial NSAPs are monomeric or oligomeric proteins containing
polypeptide components with an M
r of 25 – 30 kDa. On the basis of amino acid sequence relatedness, three different molecular families of NSAPs can be distinguished,
indicated as molecular class A, B and C, respectively. Members of each class share some common biophysical and functional
features, but may also exhibit functional differences. NSAPs have been detected in several microbial taxa, and enzymes of
different classes can be produced by the same bacterial species. Structural and phyletic relationships exist among the various
bacterial NSAPs and some other bacterial and eucaryotic phosphohydrolases. Current knowledge on bacterial NSAPs is reviewed,
together with analytical tools that may be useful for their characterization. An overview is also presented concerning the
use of bacterial NSAPs in biotechnology.
Received 21 November 1997; received after revision 10 March 1998; accepted 10 March 1998 相似文献
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