排序方式: 共有29条查询结果,搜索用时 15 毫秒
21.
Polymer-supported membranes as models of the cell surface 总被引:1,自引:0,他引:1
Lipid-bilayer membranes supported on solid substrates are widely used as cell-surface models that connect biological and artificial materials. They can be placed either directly on solids or on ultrathin polymer supports that mimic the generic role of the extracellular matrix. The tools of modern genetic engineering and bioorganic chemistry make it possible to couple many types of biomolecule to supported membranes. This results in sophisticated interfaces that can be used to control, organize and study the properties and function of membranes and membrane-associated proteins. Particularly exciting opportunities arise when these systems are coupled with advanced semiconductor technology. 相似文献
22.
Bis JC Kavousi M Franceschini N Isaacs A Abecasis GR Schminke U Post WS Smith AV Cupples LA Markus HS Schmidt R Huffman JE Lehtimäki T Baumert J Münzel T Heckbert SR Dehghan A North K Oostra B Bevan S Stoegerer EM Hayward C Raitakari O Meisinger C Schillert A Sanna S Völzke H Cheng YC Thorsson B Fox CS Rice K Rivadeneira F Nambi V Halperin E Petrovic KE Peltonen L Wichmann HE Schnabel RB Dörr M Parsa A Aspelund T Demissie S Kathiresan S Reilly MP Taylor K Uitterlinden A Couper DJ Sitzer M 《Nature genetics》2011,43(10):940-947
Carotid intima media thickness (cIMT) and plaque determined by ultrasonography are established measures of subclinical atherosclerosis that each predicts future cardiovascular disease events. We conducted a meta-analysis of genome-wide association data in 31,211 participants of European ancestry from nine large studies in the setting of the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium. We then sought additional evidence to support our findings among 11,273 individuals using data from seven additional studies. In the combined meta-analysis, we identified three genomic regions associated with common carotid intima media thickness and two different regions associated with the presence of carotid plaque (P < 5 × 10(-8)). The associated SNPs mapped in or near genes related to cellular signaling, lipid metabolism and blood pressure homeostasis, and two of the regions were associated with coronary artery disease (P < 0.006) in the Coronary Artery Disease Genome-Wide Replication and Meta-Analysis (CARDIoGRAM) consortium. Our findings may provide new insight into pathways leading to subclinical atherosclerosis and subsequent cardiovascular events. 相似文献
23.
史士财 Xie Zongwu Gao Xiaohui Jin Minghe Zhu Yingyuan Ni Fenglei Liu Hong Kraemer Erich Hirzinger Gerd 《高技术通讯(英文版)》2006,12(4):337-340
0IntroductionWiththe rapid progress of the modern science andtechnology,the acquirement and usage of resources willbe extendedtothe spacefromthe earth.But many activi-ties can not be completed without space robots,such asthe construction and maintenance of the InternationalSpace Station(ISS),the release and retrieve of the satel-lite[1,2].Since space robot has been brought forward,upto date,the Canadarm2(SSRMS)is the only real-work-ingrobot manipulator[3].ETS-VII is the worldfirst satel… 相似文献
24.
The RGD sequence generally exists in the extracellular matrix proteins and can be recognized by many integrin proteins. The binding ability of immobilized biotinylated cyclic hexapeptide [cyclo(-Arg-Gly-Asp-D-Phe-Lys-Gly-)] containing RGD to integrin a ab β3 was tested by the methods of ELISA and SPR. Results showed that a spacer of 1.48-2.2 nm between the peptide and the biotin residue was long enough to send the RGD sequence into the binding center embedded within a Ⅱbβ 3, and the equilibrium dissociation constant was 1.1 μm. The work provides an ideal model system for the research of cell adhesion on solid surfaces. 相似文献
25.
RGD序列普遍存在于细胞外基质蛋白中,并能为许多整合素蛋白所识别。利用ELISA,SPR等技术,对表面固定的人工合成生物素-含RGD环六肽〔cyclo-(Arg-Gly-Asp-D-Phe-Lys-Gly-)〕与人血小板整合素蛋白αⅡbβ3的结合能力进行了检测。结果表明,含RGD环六肽与生物素基团之间的间臂长度在1.48 ̄2.2nm时,RGD序列才能有效进入αⅡbβ3头部的反应中心并发生结合反应; 相似文献
26.
Freilinger T Anttila V de Vries B Malik R Kallela M Terwindt GM Pozo-Rosich P Winsvold B Nyholt DR van Oosterhout WP Artto V Todt U Hämäläinen E Fernández-Morales J Louter MA Kaunisto MA Schoenen J Raitakari O Lehtimäki T Vila-Pueyo M Göbel H Wichmann E Sintas C Uitterlinden AG Hofman A Rivadeneira F Heinze A Tronvik E van Duijn CM Kaprio J Cormand B Wessman M Frants RR Meitinger T Müller-Myhsok B Zwart JA Färkkilä M Macaya A Ferrari MD Kubisch C Palotie A Dichgans M 《Nature genetics》2012,44(7):777-782
Migraine without aura is the most common form of migraine, characterized by recurrent disabling headache and associated autonomic symptoms. To identify common genetic variants associated with this migraine type, we analyzed genome-wide association data of 2,326 clinic-based German and Dutch individuals with migraine without aura and 4,580 population-matched controls. We selected SNPs from 12 loci with 2 or more SNPs associated with P values of <1 × 10(-5) for replication testing in 2,508 individuals with migraine without aura and 2,652 controls. SNPs at two of these loci showed convincing replication: at 1q22 (in MEF2D; replication P = 4.9 × 10(-4); combined P = 7.06 × 10(-11)) and at 3p24 (near TGFBR2; replication P = 1.0 × 10(-4); combined P = 1.17 × 10(-9)). In addition, SNPs at the PHACTR1 and ASTN2 loci showed suggestive evidence of replication (P = 0.01; combined P = 3.20 × 10(-8) and P = 0.02; combined P = 3.86 × 10(-8), respectively). We also replicated associations at two previously reported migraine loci in or near TRPM8 and LRP1. This study identifies the first susceptibility loci for migraine without aura, thereby expanding our knowledge of this debilitating neurological disorder. 相似文献
27.
Fig. . Chemical structure of biotinylated cyclicRGD-containing hexapeptide with different spacer lengths. 《科学通报(英文版)》2000,45(23):2148-2151
The RGD sequence generally exists in the extracellular matrix proteins and can be recognized by many integrin proteins. The
binding ability of immobilized biotinylated cyclic hexapeptide [cyclo(-Arg-Gly-Asp-D-Phe-Lys-Gly-)] containing RGD to integrin
ααbβ3 was tested by the methods of ELISA and SPR. Results showed that a spacer of 1.48–2.2 nm between the peptide and the biotin
residue was long enough to send the RGD sequence into the binding center embccedded within αIIbβ3, and the equilibrium dissociation constant was 1.1 μm. The work provides an ideal model system for the research of cell adhesion
on solid surfaces. 相似文献
28.
Liao YA Rittner AS Paprotta T Li W Partridge GB Hulet RG Baur SK Mueller EJ 《Nature》2010,467(7315):567-569
Superconductivity and magnetism generally do not coexist. Changing the relative number of up and down spin electrons disrupts the basic mechanism of superconductivity, where atoms of opposite momentum and spin form Cooper pairs. Nearly forty years ago Fulde and Ferrell and Larkin and Ovchinnikov (FFLO) proposed an exotic pairing mechanism in which magnetism is accommodated by the formation of pairs with finite momentum. Despite intense theoretical and experimental efforts, however, polarized superconductivity remains largely elusive. Unlike the three-dimensional (3D) case, theories predict that in one dimension (1D) a state with FFLO correlations occupies a major part of the phase diagram. Here we report experimental measurements of density profiles of a two-spin mixture of ultracold (6)Li atoms trapped in an array of 1D tubes (a system analogous to electrons in 1D wires). At finite spin imbalance, the system phase separates with an inverted phase profile, as compared to the 3D case. In 1D, we find a partially polarized core surrounded by wings which, depending on the degree of polarization, are composed of either a completely paired or a fully polarized Fermi gas. Our work paves the way to direct observation and characterization of FFLO pairing. 相似文献
29.
Qi M Lidorikis E Rakich PT Johnson SG Joannopoulos JD Ippen EP Smith HI 《Nature》2004,429(6991):538-542
Photonic crystals offer unprecedented opportunities for miniaturization and integration of optical devices. They also exhibit a variety of new physical phenomena, including suppression or enhancement of spontaneous emission, low-threshold lasing, and quantum information processing. Various techniques for the fabrication of three-dimensional (3D) photonic crystals--such as silicon micromachining, wafer fusion bonding, holographic lithography, self-assembly, angled-etching, micromanipulation, glancing-angle deposition and auto-cloning--have been proposed and demonstrated with different levels of success. However, a critical step towards the fabrication of functional 3D devices, that is, the incorporation of microcavities or waveguides in a controllable way, has not been achieved at optical wavelengths. Here we present the fabrication of 3D photonic crystals that are particularly suited for optical device integration using a lithographic layer-by-layer approach. Point-defect microcavities are introduced during the fabrication process and optical measurements show they have resonant signatures around telecommunications wavelengths (1.3-1.5 microm). Measurements of reflectance and transmittance at near-infrared are in good agreement with numerical simulations. 相似文献