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191.
17q11 microdeletions that encompass NF1 cause 5%-10% of cases of neurofibromatosis type 1, and individuals with microdeletions are typically taller than individuals with intragenic NF1 mutations, suggesting that deletion of a neighboring gene might promote human growth. We identified mutations in RNF135, which is within the NF1 microdeletion region, in six families characterized by overgrowth, learning disability, dysmorphic features and variable additional features. These data identify RNF135 as causative of a new overgrowth syndrome and demonstrate that RNF135 haploinsufficiency contributes to the phenotype of NF1 microdeletion cases.  相似文献   
192.
The major function of vascular smooth muscle cells (SMCs) is contraction to regulate blood pressure and flow. SMC contractile force requires cyclic interactions between SMC alpha-actin (encoded by ACTA2) and the beta-myosin heavy chain (encoded by MYH11). Here we show that missense mutations in ACTA2 are responsible for 14% of inherited ascending thoracic aortic aneurysms and dissections (TAAD). Structural analyses and immunofluorescence of actin filaments in SMCs derived from individuals heterozygous for ACTA2 mutations illustrate that these mutations interfere with actin filament assembly and are predicted to decrease SMC contraction. Aortic tissues from affected individuals showed aortic medial degeneration, focal areas of medial SMC hyperplasia and disarray, and stenotic arteries in the vasa vasorum due to medial SMC proliferation. These data, along with the previously reported MYH11 mutations causing familial TAAD, indicate the importance of SMC contraction in maintaining the structural integrity of the ascending aorta.  相似文献   
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文中主要研究了植物过滤系统对改善室内空气品质的作用.通过实验比较了韩国本土和外来植物对室内空气污染物的净化作用.实验在夏季进行,将4种植物放入尺寸相同的样板房间,在相同实验条件下,对放入和未放入植物的样板房间内的苯、甲苯、乙苯、二甲苯和甲醛等有害物质的浓度加以监测,同时在植物放入3小时及3天后分别测定易挥发有机物(VOCs)的浓度;由此了解、比较和估计了两种外来植物和两种本土植物对易挥发有机化合物的净化效果.结果发现:(1)在所有实验中,置入植物的房间对VOCs物质的净化效果均比未置入植物的房间的大,而且外来植物对大多数VOCs物质的净化效果比本土植物更显著;(2)在种植和生长的空间实验中,本杰明橡胶树覆盖实验空间10%时净化效果最佳,该树对甲醛的净化效果尤其明显;(3)在种植和生长的空间实验中,盆栽金皇后种植在有阳光的地方时净化效果最佳,该植物对甲苯的净化效果最强.  相似文献   
195.
A high-resolution map of active promoters in the human genome   总被引:1,自引:0,他引:1  
Kim TH  Barrera LO  Zheng M  Qu C  Singer MA  Richmond TA  Wu Y  Green RD  Ren B 《Nature》2005,436(7052):876-880
  相似文献   
196.
The human X chromosome has a unique biology that was shaped by its evolution as the sex chromosome shared by males and females. We have determined 99.3% of the euchromatic sequence of the X chromosome. Our analysis illustrates the autosomal origin of the mammalian sex chromosomes, the stepwise process that led to the progressive loss of recombination between X and Y, and the extent of subsequent degradation of the Y chromosome. LINE1 repeat elements cover one-third of the X chromosome, with a distribution that is consistent with their proposed role as way stations in the process of X-chromosome inactivation. We found 1,098 genes in the sequence, of which 99 encode proteins expressed in testis and in various tumour types. A disproportionately high number of mendelian diseases are documented for the X chromosome. Of this number, 168 have been explained by mutations in 113 X-linked genes, which in many cases were characterized with the aid of the DNA sequence.  相似文献   
197.
Aspergillus fumigatus is exceptional among microorganisms in being both a primary and opportunistic pathogen as well as a major allergen. Its conidia production is prolific, and so human respiratory tract exposure is almost constant. A. fumigatus is isolated from human habitats and vegetable compost heaps. In immunocompromised individuals, the incidence of invasive infection can be as high as 50% and the mortality rate is often about 50% (ref. 2). The interaction of A. fumigatus and other airborne fungi with the immune system is increasingly linked to severe asthma and sinusitis. Although the burden of invasive disease caused by A. fumigatus is substantial, the basic biology of the organism is mostly obscure. Here we show the complete 29.4-megabase genome sequence of the clinical isolate Af293, which consists of eight chromosomes containing 9,926 predicted genes. Microarray analysis revealed temperature-dependent expression of distinct sets of genes, as well as 700 A. fumigatus genes not present or significantly diverged in the closely related sexual species Neosartorya fischeri, many of which may have roles in the pathogenicity phenotype. The Af293 genome sequence provides an unparalleled resource for the future understanding of this remarkable fungus.  相似文献   
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During the last decade, a growing corpus of evidence has indicated an important role of inflammatory cytokines in the pathogenesis of cerebral lesion following stroke. Recent data suggest that genetics may in turn contribute to modulating the effects of inflammatory cytokines on cerebral infarction (CI). This paper reviews the physiologic characteristics of major inflammatory cytokines and recent research developments related to cell biology and pathobiology in CI. In particular, this review focuses on the genetic aspects of inflammatory cytokines and their implications in CI.Received 22 June 2004; received after revision 11 November 2004; accepted 16 December 2004  相似文献   
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