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31.
卡尔·兰斯泰纳(Karl.landsteiner)于1901年发现了人类血型抗原,并把人类血液分为A、B、O和AB型,从而开创了现代输血的新纪元。血型的研究,对认识迄今输血失败的原因起到了至关重要的作用。 相似文献
32.
An eco- and inno-product design system applying integrated and intelligent qfde and triz methodology 总被引:2,自引:0,他引:2
Amy J. C. Trappey Jerry J. R. Ou Gilbert Y. P. Lin Meng-Yu Chen 《系统科学与系统工程学报(英文版)》2011,20(4):443-459
The green environmental laws and regulations are legislated, implemented, and enforced in many countries and economic regions.
The provision of green products and services are the fast growing trend in global consumer markets. Therefore, introducing
new products with environmental considerations becomes critical for global brand manufacturers. This research depicts an integrated
and intelligent eco- and inno-product design methodology to support environmental friendly green product development. The
methodology adopts approaches, such as life cycle assessment (LCA), quality function deploymnet for environement (QFDE), theory
of inventive problem solving (TRIZ) and back-propagation network (BPN) to achieve eco- and inno-design objectives. LCA evaluates
and compares the environmental impacts of production. QFDE transforms high-level concerns of environment into design requirements.
When there are many historical QFDE data, the BPN prediction model is trained and deployed to automate the specifications
of green design improvement. TRIZ is to support the creation of innovative product design ideas effectively and efficiently
during the concept design stage. Finally, this paper presents two eco-design cases of power adaptor to demonstrate the proposed
methodology. 相似文献
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Wingert RA Galloway JL Barut B Foott H Fraenkel P Axe JL Weber GJ Dooley K Davidson AJ Schmid B Schmidt B Paw BH Shaw GC Kingsley P Palis J Schubert H Chen O Kaplan J Zon LI;Tübingen Screen Consortium 《Nature》2005,436(7053):1035-1039
Iron is required to produce haem and iron-sulphur (Fe-S) clusters, processes thought to occur independently. Here we show that the hypochromic anaemia in shiraz (sir) zebrafish mutants is caused by deficiency of glutaredoxin 5 (grx5), a gene required in yeast for Fe-S cluster assembly. We found that grx5 was expressed in erythroid cells of zebrafish and mice. Zebrafish grx5 rescued the assembly of grx5 yeast Fe-S, showing that the biochemical function of grx5 is evolutionarily conserved. In contrast to yeast, vertebrates use iron regulatory protein 1 (IRP1) to sense intracellular iron and regulate mRNA stability or the translation of iron metabolism genes. We found that loss of Fe-S cluster assembly in sir animals activated IRP1 and blocked haem biosynthesis catalysed by aminolaevulinate synthase 2 (ALAS2). Overexpression of ALAS2 RNA without the 5' iron response element that binds IRP1 rescued sir embryos, whereas overexpression of ALAS2 including the iron response element did not. Further, antisense knockdown of IRP1 restored sir embryo haemoglobin synthesis. These findings uncover a connection between haem biosynthesis and Fe-S clusters, indicating that haemoglobin production in the differentiating red cell is regulated through Fe-S cluster assembly. 相似文献
36.
Telomere-binding factors and general DNA repair 总被引:2,自引:0,他引:2
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Michaloglou C Vredeveld LC Soengas MS Denoyelle C Kuilman T van der Horst CM Majoor DM Shay JW Mooi WJ Peeper DS 《Nature》2005,436(7051):720-724
Most normal mammalian cells have a finite lifespan, thought to constitute a protective mechanism against unlimited proliferation. This phenomenon, called senescence, is driven by telomere attrition, which triggers the induction of tumour suppressors including p16(INK4a) (ref. 5). In cultured cells, senescence can be elicited prematurely by oncogenes; however, whether such oncogene-induced senescence represents a physiological process has long been debated. Human naevi (moles) are benign tumours of melanocytes that frequently harbour oncogenic mutations (predominantly V600E, where valine is substituted for glutamic acid) in BRAF, a protein kinase and downstream effector of Ras. Nonetheless, naevi typically remain in a growth-arrested state for decades and only rarely progress into malignancy (melanoma). This raises the question of whether naevi undergo BRAF(V600E)-induced senescence. Here we show that sustained BRAF(V600E) expression in human melanocytes induces cell cycle arrest, which is accompanied by the induction of both p16(INK4a) and senescence-associated acidic beta-galactosidase (SA-beta-Gal) activity, a commonly used senescence marker. Validating these results in vivo, congenital naevi are invariably positive for SA-beta-Gal, demonstrating the presence of this classical senescence-associated marker in a largely growth-arrested, neoplastic human lesion. In growth-arrested melanocytes, both in vitro and in situ, we observed a marked mosaic induction of p16(INK4a), suggesting that factors other than p16(INK4a) contribute to protection against BRAF(V600E)-driven proliferation. Naevi do not appear to suffer from telomere attrition, arguing in favour of an active oncogene-driven senescence process, rather than a loss of replicative potential. Thus, both in vitro and in vivo, BRAF(V600E)-expressing melanocytes display classical hallmarks of senescence, suggesting that oncogene-induced senescence represents a genuine protective physiological process. 相似文献