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排序方式: 共有112条查询结果,搜索用时 125 毫秒
81.
Irobi J Van Impe K Seeman P Jordanova A Dierick I Verpoorten N Michalik A De Vriendt E Jacobs A Van Gerwen V Vennekens K Mazanec R Tournev I Hilton-Jones D Talbot K Kremensky I Van Den Bosch L Robberecht W Van Vandekerckhove J Van Broeckhoven C Gettemans J De Jonghe P Timmerman V 《Nature genetics》2004,36(6):597-601
Distal hereditary motor neuropathies are pure motor disorders of the peripheral nervous system resulting in severe atrophy and wasting of distal limb muscles. In two pedigrees with distal hereditary motor neuropathy type II linked to chromosome 12q24.3, we identified the same mutation (K141N) in small heat-shock 22-kDa protein 8 (encoded by HSPB8; also called HSP22). We found a second mutation (K141E) in two smaller families. Both mutations target the same amino acid, which is essential to the structural and functional integrity of the small heat-shock protein alphaA-crystallin. This positively charged residue, when mutated in other small heat-shock proteins, results in various human disorders. Coimmunoprecipitation experiments showed greater binding of both HSPB8 mutants to the interacting partner HSPB1. Expression of mutant HSPB8 in cultured cells promoted formation of intracellular aggregates. Our findings provide further evidence that mutations in heat-shock proteins have an important role in neurodegenerative disorders. 相似文献
82.
Zusammenfassung Die Permeabilitätsverhältnisse der Blut-Hirn-Schranke nach spezifischer Hemmung der 5-Nucleosid-Phosphatase wurden mittels Fluoreszenzmikroskopie studiert und eine Permeabilitätserhöhung nach Injektion von Nickelchlorid gefunden: Trypanblau kann dabei ins Gehirn penetrieren, was dafür spricht, dass die 5-Nucleosid-Phosphatase bei der Regulation der Kapillarpermeabilität eine bedeutende Rolle spielt. 相似文献
83.
Functional hydrogel structures for autonomous flow control inside microfluidic channels 总被引:1,自引:0,他引:1
Hydrogels have been developed to respond to a wide variety of stimuli, but their use in macroscopic systems has been hindered by slow response times (diffusion being the rate-limiting factor governing the swelling process). However, there are many natural examples of chemically driven actuation that rely on short diffusion paths to produce a rapid response. It is therefore expected that scaling down hydrogel objects to the micrometre scale should greatly improve response times. At these scales, stimuli-responsive hydrogels could enhance the capabilities of microfluidic systems by allowing self-regulated flow control. Here we report the fabrication of active hydrogel components inside microchannels via direct photopatterning of a liquid phase. Our approach greatly simplifies system construction and assembly as the functional components are fabricated in situ, and the stimuli-responsive hydrogel components perform both sensing and actuation functions. We demonstrate significantly improved response times (less than 10 seconds) in hydrogel valves capable of autonomous control of local flow. 相似文献
84.
Seung-Jae Lee In Hwan Lee Jeong Hun Park So-Jung Gwak Jong-Won Rhie Dong-Woo Cho Tae Jo Ko Dong Sung Kim 《科学通报(英文版)》2009,54(19):3608-3612
We developed a hybrid scaffold and a bioreactor for cartilage regeneration. The hybrid scaffold was developed as combination of two components: a biodegradable framework and hydrogel-containing chondrocytes. We performed the MTT cell proliferation assay to compare the proliferation and viability of chondrocytes on three types of scaffolds: an aiginate gel, the hybrid scaffold, and an alginate sponge. Cells were encapsulated in 2% agarose gel. The bioreactor consisted of a circulation system and a compression system. We performed dynamic cell culture on these agarose gels in the bioreactor for 3 days. 相似文献
85.
Forecasting the US Term Structure of Interest Rates Using Nonparametric Functional Data Analysis
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In this paper we consider a novel procedure to forecasting the US zero coupon bond yields for a continuum of maturities by using the methodology of nonparametric functional data analysis (NP‐FDA). We interpret the US yields as curves since the term structure of interest rates defines a relation between the yield of a bond and its maturity. Within the NP‐FDA approach, each curve is viewed as a functional random variable and the dynamics present in the sample are modeled without imposing any parametric structure. In order to evaluate forecast the performance of the proposed estimator, we consider forecast horizons h = 1,3,6,12… months and the results are compared with widely known benchmark models. Our estimates with NP‐FDA present predictive performance superior to its competitors in many situations considered, especially for short‐term maturities. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
86.
Daniela Aparecida Savariz Bôlla Fernando Carvalho Jairo José Zocche Alexandre Bianco João Antônio de Bittencourt Vitto Raphael dos Santos 《Journal of Natural History》2017,51(47-48):2947-2953
Bats (Chiroptera), one of the most diverse groups in terms of taxonomy, morphology and ecology, are known for their nocturnal behaviour of flight and feeding. Although there is no consensus on the evolution of nocturnality in bats, many authors mention risk of predation, overheating, competition and mobbing by non-competitor species as arguments to justify nocturnal instead of daytime flight in bats. Herein we describe the first records of three genera of phyllostomid bats flying, foraging and drinking water during daytime in the Brazilian Amazon. All taxa were recorded drinking water, and some Phyllostomus sp. individuals were recorded foraging on termites, alongside birds. Risk of dehydration and overheating in roosts, as well as low competition in daytime, may explain the emergence of phyllostomid bats before sunset. 相似文献
87.
Genetic Analysis of Psoriasis Consortium & the Wellcome Trust Case Control Consortium Strange A Capon F Spencer CC Knight J Weale ME Allen MH Barton A Band G Bellenguez C Bergboer JG Blackwell JM Bramon E Bumpstead SJ Casas JP Cork MJ Corvin A Deloukas P Dilthey A Duncanson A Edkins S Estivill X Fitzgerald O Freeman C Giardina E Gray E Hofer A Hüffmeier U Hunt SE Irvine AD Jankowski J Kirby B Langford C Lascorz J Leman J Leslie S Mallbris L Markus HS Mathew CG McLean WH McManus R 《Nature genetics》2010,42(11):985-990
To identify new susceptibility loci for psoriasis, we undertook a genome-wide association study of 594,224 SNPs in 2,622 individuals with psoriasis and 5,667 controls. We identified associations at eight previously unreported genomic loci. Seven loci harbored genes with recognized immune functions (IL28RA, REL, IFIH1, ERAP1, TRAF3IP2, NFKBIA and TYK2). These associations were replicated in 9,079 European samples (six loci with a combined P < 5 × 10?? and two loci with a combined P < 5 × 10??). We also report compelling evidence for an interaction between the HLA-C and ERAP1 loci (combined P = 6.95 × 10??). ERAP1 plays an important role in MHC class I peptide processing. ERAP1 variants only influenced psoriasis susceptibility in individuals carrying the HLA-C risk allele. Our findings implicate pathways that integrate epidermal barrier dysfunction with innate and adaptive immune dysregulation in psoriasis pathogenesis. 相似文献
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