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131.
Vitreous samples collected in retinopathic surgeries have diverse properties, making proteomics analysis difficult. We report a cluster analysis to evade this difficulty. Vitreous and subretinal fluid samples were collected from 60 patients during surgical operation of non‐proliferative diabetic retinopathy, proliferative diabetic retinopathy, proliferative vitreoretinopathy, and rhegmatogenous retinal detachment. For controls, we collected vitreous fluid from patients of idiopathic macular hole, epiretinal, and from a healthy postmortem donor. Proteins from these samples were subjected to quantitative proteomics using two‐dimensional gel electrophoresis. We selected 105 proteins robustly expressed among ca. 400 protein spots and subjected them to permutation test. By using permutation test analysis we observed unique variations in the expression of some of these proteins in vitreoretinal diseases when compared to the control and to each other: (i) the levels of inflammation‐associated proteins such as alpha1‐antitrypsin, apolipoprotein A4, albumin, and transferrin were significantly higher in all four types of vitreoretinal diseases, and (ii) each vitreoretinal disease elevated a unique set of proteins, which can be interpreted based on the pathology of retinopathy. Our protocol will be effective for the study of protein expression in other types of clinical samples of diverse properties.  相似文献   
132.
Recently, unimolecular devices have attracted significant attention as a ‘post-silicon technology’ to enable the fabrication of future nanoscale electronic devices. In this paper, we describe a candidate molecule for a rectifier function using porphyrin polymer and a photovoltaic cell using fullerene-based supramolecule. We have investigated the geometric and electronic structure of these organic molecules using an ab initio quantum mechanical calculation. These results for the porphyrin polymers show that the localization of the unoccupied orbital state on the acceptor moiety mostly depends on their structures. The calculated results for the electronic structure of a naphthalocyanine–fullerene supramolecule manifest that the HOMO’s were localized on the donor sub-unit and the LUMO’s were localized on theacceptor sub-unit.  相似文献   
133.
134.
A single microparticle launching method is described to simulate the hypervelocity impacts of micrometeoroids and microdebris on space structures at the Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency. A microparticle placed in a sabot with slits is accelerated using a rifled two-stage light-gas gun. The centrifugal force provided by the rifling in the launch tube separates the sabot. The sabot-separation distance and the impact-point deviation are strongly affected by the combination of the sabot diameter and the bore diameter, and by the projectile diameter. Using this method, spherical projectiles of 1.0-0.1 mm diameter were launched at up to 7 km/s.  相似文献   
135.
The aggregation of Au nanoparticle (AuNP) on a glass surface functionalized with 3-aminopropyltrimethoxysilane (APTMS) was studied by means of UV-vis spectroscopy and AFM measurements. The optical response of AuNP due to localized surface plasmon resonance (LSPR) was increased with the increment of AuNP amount on the functionalized glass surface, then the changes of spectral shape corresponds to the aggregate formation was finally observed. The AFM image shows in homogeneous aggregation of nanoparticles on the substrate surface. Three-dimensional aggregate growth was observed.  相似文献   
136.
We prepared 4'-pentylbiphenyl-4-carbonitrile (5CB)-stabilized rhodium (5CB-Rh) nanoparticles and poly(cyclodextrin) (PCyD)-stabilized rhodium (PCyD-Rh) nanoparticles. The average diameter of Rh nanoparticles stabilized by 5CB, PalphaCyD, PbetaCyD, and PgammaCyD are 1.2, 5.4, 6.8, and 5.2 nm, respectively. The nanoparticles were dispersed in liquid crystal 5CB to construct novel twisted nematic liquid crystal device (TN-LCD). Voltage holding ratio was measured for TN-LCD fabricated by doping PbetaCyD-Rh nanoparticles. The decrement of the voltage was very much reduced for that doped with PbetaCyD-Rh. The response time of this TN-LCD in the presence of PbetaCyD-Rh nanoparticles was faster than that in the absence.  相似文献   
137.
热处理温度对莫来石-铝矾土-氮化硅复合材料性能的影响   总被引:1,自引:0,他引:1  
以莫来石、铝矾土、氮化硅为主要原料,铝酸钙水泥、硅微粉为结合剂,研究了不同热处理温度对莫来石-铝矾土-氮化硅复合材料性能的影响。结果表明:随着热处理温度的提高,莫来石-铝矾土-氮化硅复合材料的热膨胀系数在1400℃时出现最小值2.59×10-6℃-1;体积密度随着热处理温度的提高呈现先减小后增大再减小的变化规律;线变化率随热处理温度的提高呈现收缩先增大后减小的变化规律;常温抗折强度随着热处理温度的提高先增大后减小;常温耐压强度随着热处理温度的提高而增大。  相似文献   
138.
A human fibroblast cDNA expression library was screened for cDNA clones giving rise to flat colonies when transfected into v-Ki-ras-transformed NIH 3T3 cells. One such gene, RECK, encodes a membrane-anchored glycoprotein of about 110 kDa with multiple epidermal growth factor-like repeats and serine-protease inhibitor-like domains. While RECK mRNA is expressed in various human tissues and untransformed cells, it is undetectable in tumor-derived cell lines and oncogenically transformed cells. Restored expression of RECK in malignant cells resulted in suppression of invasive activity with concomitant decrease in the secretion of matrix metalloproteinase-9 (MMP-9), a key enzyme involved in tumor invasion and metastasis. Moreover, purified RECK protein was found to bind to, and inhibit the proteolytic activity of, MMP-9. Thus, RECK may link oncogenic signals to tumor invasion and metastasis.  相似文献   
139.
For the prediction of the leaching behavior of actinide elements contained in the fuel debris that has arisen from the severe accident in Fukushima Daiichi Nuclear Power Station (NPS), a simulated fuel debris consisting of UO2–ZrO2 solid solution doped with 137Cs, 237Np, 236Pu and 241Am tracers was synthesized, and agitated leaching tests were conducted for the simulated fuel debris in seawater. The synthesized simulated fuel debris was immersed and shaken in natural seawater collected at a coast 11 km away from Fukushima Daiichi NPS. The brief leaching test conditions were T = 25 °C and solid–liquid ratio = 4 g/l, and the test duration was up to 31 days. The ratio of tracers leached into seawater from the simulated fuel debris by the agitated leaching test for 4 days was evaluated to be 0.09% for U, 0.01% for Np, 0.01% for Pu, 0.01% for Am and 35.39% for Cs by the α or γ spectrometry of the soluble fraction. The leaching of actinides from the real fuel debris in reactor units 1–3 in Fukushima Daiichi NPS is expected to be suppressed in comparison with that from normal light water reactor spent fuel.  相似文献   
140.
For the asymmetric hydrophosphonylation of aldehydes, an efficient organocatalytic approach with a diaminomethylenemalononitrile‐based hydrogen‐bonding donor catalyst is presented. The catalyst induces high yields and excellent enantioselectivities (up to 98% yield, 96% ee).

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