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排序方式: 共有713条查询结果,搜索用时 15 毫秒
51.
52.
Yoshihito Nakagawa Yukihiro Akao Kohei Taniguchi Akemi Kamatani Tomomitsu Tahara Toshiaki Kamano Naoko Nakano Naruomi Komura Hirokazu Ikuno Takafumi Ohmori Yasutaka Jodai Masahiro Miyata Mistuo Nagasaka Tomoyuki Shibata Naoki Ohmiya Ichiro Hirata 《International journal of molecular sciences》2015,16(1):1526-1543
Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors. 相似文献
53.
Furukawa S Narisawa N Watanabe T Kawarai T Myozen K Okazaki S Ogihara H Yamasaki M 《International journal of food microbiology》2005,102(1):107-111
Effects of the clumping of bacterial spores on their heat resistance as a result of heat treatment were investigated. Spore suspensions of Bacillus cereus, Bacillus coagulans and Bacillus licheniformis were heated at 85 degrees C. Survivor curves of the three strains showed tailing in all treatments after 30 min. As the treatment time increased, the formation of spore clumps increased in all strains after 20 min. Relative hydrophobicity of the spore surface increased as a result of heat treatment. The effect of spore concentration on the inactivation of the B. licheniformis spores was investigated, and surviving curves showed no tailing below a concentration of 4.9 log CFU/ml. 相似文献
54.
This paper describes an unusual behavior detection system based on an omnidirectional vision sensor, as one of the important elements in realizing “Sensing and Robotic Support Rooms” for elderly people. Such support rooms are expected to be further developed in the future with advanced abilities to automatically recognize elderly people's actions and behavior patterns, to detect unusual patterns by using sensors, and to support their daily motions by using robotic manipulator control systems. The proposed monitoring system using an omnidirectional vision sensor automatically learns daily behavior patterns and detects unusual behavior patterns and actions by using the Bayesian network approach. The Bayesian network is constructed by using image feature values such as area and center‐of‐gravity values extracted from a captured image sequence, and the respective behavior patterns are represented as conditional probabilities. Unusual behavior patterns can be automatically detected on the basis of the low generation probability values. Experiments based on the investigation of elderly people's typical daily behavior patterns have shown the effectiveness of the proposed system. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 172(3): 42–51, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20990 相似文献
55.
Hajime Araki Taichi Kaji Masahito Yamamoto Keiji Suzuki Azuma Ohuchi 《Electrical Engineering in Japan》2001,135(4):43-51
The optimal sequential problem is defined as the problem of finding the minimum cost partition of the nodes of a directed acyclic graph into subsets of a given size, subject to the constraint that the precedence relationships among the elements are satisfied. A heuristic algorithm based on tabu search has been proposed for this problem [2]. However, there is a tendency for the solutions obtained by tabu search to become trapped in bad local optima in parallel graphs with random edge costs. In this paper we present a genetic algorithm for the optimal sequential partitioning problem. We develop an effective two‐point partial order crossover satisfying sequential conditions, which preserve better blocks that have a larger sum of edge costs. In this crossover we introduce the roulette selection method to escape local optima. We also assess the effectiveness of the algorithm. The results show that this proposed algorithm outperforms any other algorithm using tabu search in terms of solution quality. © 2001 Scripta Technica, Electr Eng Jpn, 135(4): 43–51, 2001 相似文献
56.
Takao Yasui Noritada Kaji Yukihiro Okamoto Manabu Tokeshi Yasuhiro Horiike Yoshinobu Baba 《Microfluidics and nanofluidics》2013,14(6):961-967
Recent developments of nanofabrication techniques have created a trend switching from randomly ordered polymeric matrices, such as gel, to highly ordered sieving nanostructures in the separation of biomolecules. These nanostructures have enormous potential for fast separation of biomolecules, while nanostructure-based separation techniques suffer from critical scaling problems; they are efficient in handling less than nanoliter amounts of sample fluids, but most biomolecule samples are available in a liquid volume that is over several microliter, leading to a reduction in sensitivity and resolution. In this study, we developed a nanopillar array chip integrated with an easy and rapid on-line stacking method and achieved fast DNA separation with high sensitivity and high resolution. The developed on-line stacking method is based on the balance of two forces driven by electric fields: electroosmotic flow (EOF) and electrophoresis. The EOF mobility from the microchannel to the nanopillar-channel is drastically decreased, while, on the other hand, electrophoresis has constant mobilities in the whole length of the channels. The on-line stacking was realized at the well-balanced position of the two forces, and the on-line stacking using the nanopillar array chip can also be achieved within 10 s by just applying electric voltages without any other special reagents and materials. After applying on-line stacking using the nanopillar array chip, the relative fluorescence intensity increased 1,000-fold, and the resolution was twice as good as that without on-line stacking. 相似文献
57.
Hydrothermal flames in supercritical water oxidation: investigation in a pilot scale continuous reactor 总被引:1,自引:0,他引:1
Roberto M. Serikawa Takashi UsuiTatuya Nishimura Hirokazu SatoShusaku Hamada Hideo Sekino 《Fuel》2002,81(9):1147-1159
Hydrothermal flames at 25 MPa supercritical water environment were investigated using a 4800 ml reaction tower, in which the sapphire windows were fitted for optical access. Down flowing hydrothermal flames were observed for oxidation of 2-propanol when the reactor was fed with inlet organic concentration higher than 2 vol% and air ratio higher than 1.8. Flame temperature, as high as 1100 °C, was measured by means of a thermocouple and the temperature was found to be strongly influenced by air ratio. Effective and stable oxidation of organics with TOC removal rate of 99.9% was achieved. Dioxins were also decomposed with a ratio higher than 99.9%, within 1 min reaction time in this reactor configuration. 相似文献
58.
Takanori Sone Hirokazu Akagi Hisao Watarai 《Journal of the American Ceramic Society》1991,74(12):3151-3153
Pore behavior as influenced by migration of an abnormal grain boundary was studied. The pore behavior during the discontinuous growth of hot-pressed spinel (MgAl2 O4 ) — whether the pore can move attached to the grain boundary — is particularly governed by the pore size and the matrix grain size. These phenomena can be understood from the interaction between the pore and the abnormal grain boundary. 相似文献
59.
Shin’ichi Konno Shigeo Kazama Maki Hiraoka Hirokazu Sakamoto Kenji Mizoguchi Hiromi Taniguchi Toshikazu Nakamura Kou Furukawa 《Journal of Low Temperature Physics》2006,142(3-4):621-624
β′-(BEDT-TTF)(TCNQ) is a compound of BEDT-TTF (=ET) and TCNQ molecules aligned orthogonally with each other, forming two-dimensional
sheets and one-dimensional columns of 1/4-filled π band, respectively. It is known that the metal-insulator transition occurs
at 330 K at ambient pressure. We have measured the electronic spin susceptibility by means of the EPR-NMR method at 50 MHz,
and the angular dependence of g-factor and line width of EPR both at Q (34 GHz) and W (94 GHz) band. We successfully confirmed
that the antiferromagnetic transition occurs in ET sheets and TCNQ columns, independently. 相似文献
60.
Basic fibroblast growth factor (FGF-2) is not only a potent mitogen for various cells but also a multifunctional factor with angiogenic and chemotactic activity, and the capacity to induce the synthesis of various proteinases and to modulate endocrine function. To clarify the role played by FGF-2 in the progression of pituitary tumor, we fused rat FGF-2 cDNA to the promoter SR alpha, consisting of the early promoter of SV40 and HTLV(I)-LTR, and we cotransfected GH3 cells with pSV2-neo by an electroporation method. After selection by G418, we obtained 7 neomycin-resistant clones. Southern blot analysis of genomic DNA revealed the presence of transfected rat FGF-2 cDNA in 4 of the 7 clones. To measure FGF-2 molecules, we established a new immuno-fluorometric assay system, using 3 monoclonal antibodies against different portions of human FGF-2. This assay had a minimum sensitivity of 10 pg/ml and cross-reacted neither with acidic fibroblast growth factor (FGF-1) nor insulin-like growth factor 1 (IGF-1), even at a concentration of 100 ng/ml. Although FGF-2 was undetectable in the culture medium of any of the clones, the cell homogenate contained a significant amount of FGF-2 (7.2 ng/mg protein) in 1 of the 4 FGF-2-transfected clones (GH3FGF(+)), whereas FGF-2 was not detected (< 5.2 pg/mg protein) in the cell homogenates of either the parent GH3 cells or the control cells transfected with pSV2-neo alone (GH3FGF(-)), GH3FGF(+) grew as adherent cells and formed epithelial sheets with a growth rate similar to that of control cells. The amount of prolactin(PRL) released by TRH was greater in GH3FGF(+) than that in GH3 or GH3FGF(-). On the other hand, the sensitivity to SRIF was increased in GH3FGF(+) compared with that in other clones. The findings of these in vitro studies indicate that FGF-2, if it is expressed in pituitary tumor cells, plays little if any role in cell growth but may modulate certain cell functions such as responsiveness to hormones. 相似文献