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排序方式: 共有1891条查询结果,搜索用时 296 毫秒
81.
Kaname Uno Shohei Iyoshi Masato Yoshihara Kazuhisa Kitami Kazumasa Mogi Hiroki Fujimoto Mai Sugiyama Yoshihiro Koya Yoshihiko Yamakita Akihiro Nawa Tomohiro Kanayama Hiroyuki Tomita Atsushi Enomoto Hiroaki Kajiyama 《International journal of molecular sciences》2022,23(8)
Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy and has a unique metastatic route using ascites, known as the transcoelomic root. However, studies on ascites and contained cellular components have not yet been sufficiently clarified. In this review, we focus on the significance of accumulating ascites, contained EOC cells in the form of spheroids, and interaction with non-malignant host cells. To become resistant against anoikis, EOC cells form spheroids in ascites, where epithelial-to-mesenchymal transition stimulated by transforming growth factor-β can be a key pathway. As spheroids form, EOC cells are also gaining the ability to attach and invade the peritoneum to induce intraperitoneal metastasis, as well as resistance to conventional chemotherapy. Recently, accumulating evidence suggests that EOC spheroids in ascites are composed of not only cancer cells, but also non-malignant cells existing with higher abundance than EOC cells in ascites, including macrophages, mesothelial cells, and lymphocytes. Moreover, hetero-cellular spheroids are demonstrated to form more aggregated spheroids and have higher adhesion ability for the mesothelial layer. To improve the poor prognosis, we need to elucidate the mechanisms of spheroid formation and interactions with non-malignant cells in ascites that are a unique tumor microenvironment for EOC. 相似文献
82.
Yoshinori Nishiki Koichi Aoki Koichi Tokuda Hiroaki Matsuda 《Journal of Applied Electrochemistry》1987,17(1):67-76
On the basis of the observation of gas bubbles evolved by electrolysis, a two-dimensional vertical model cell composed of electrodes with open parts for releasing gas bubbles to the back side is proposed. The model cell consists of two layers. One layer forms a bubble curtain with a maximum volume fraction of gas bubbles in the vicinity of the working electrode with open parts. The other. being located out of the bubble layer, is a convection layer with a small volume fraction distributed in the vertical direction under forced convection conditions. The cell resistance and the current distribution were computed by the finite element method when resistivity in the back side varied in the vertical direction along the cell. The following three cases for overpotential were considered: no overpotential, overpotential of the linear type and overpotential of the Butler-Volmer type. It was found that the cell resistance was determined not only by the interelectrode gap but also by the percentage of open area and in some cases by the superficial surface area. The cell resistance varied only slightly with the distribution of the bubble layer in the back side.Nomenclature
b
linear overpotential coefficient given byb=/i
-
C
proportionality constant given by Equation 15
-
d
1
distance between front side of working electrode and separator
-
d
2
thickness of separator
-
F
Faraday constant
-
I
total current per half pitch
-
i
current density at working electrode
-
i
0
exchange current density
-
L
length of a real electrolysis cell
-
n
number of electrons transferred in electrode reaction
-
O
p
percentage of open area given by Equation 1
-
p
pitch, i.e. twice the length of the unit cell, defined by 2(BC) in Fig. 4
-
q
thickness of bubble curtain, defined by (AM) in Fig. 4
-
R
gas constant
-
r
t
total cell resistance
-
r
unit-cell resistance defined by (V – V
eq)/I
-
r
rs
residue ofr from sum ofr
0 andr
-
r
0
ohmic resistance of solution when0
p=0
-
r
resistance due to overpotential when0
p=0
-
s
electrode surface ratio or superficial surface area given by Equation 2 for the present model
-
T
absolute temperature
-
t
thickness of working electrode defined by EF in Fig. 4
-
V
cell voltage
-
V
eq
open circuit potential difference between working and counter electrodes
-
solution velocity in cell
- 0
solution velocity at bottom of cell
-
w
width of working electrode, defined by 2(DE) in Fig. 4
-
x
abscissa located on cell model
-
y
ordinate located on cell model
-
anodic transfer coefficient
-
linear overpotential kinetic parameter defined byb/[bc(p/2)]
- d
infinitesimally small length on the boundary
-
volume fraction of gas bubbles in cell
-
dimensionless cell voltage defined bynF(V – V
eq)/RT
-
overpotential at working electrode
-
Butler-Volmer overpotential kinetic parameter defined by [nFi
0bc(p/2)]/RT
-
coordinate perpendicular to boundary of model cell
- 1
resistivity of bubble-free solution
- 2
resistivity of separator
- bc
resistivity of bubble curtain
-
potential in cell 相似文献
83.
Hiroaki Takeda Masataka Ohgaki Takashi Kizuki Kazuaki Hashimoto Yoshitomo Toda Shigekazu Udagawa Kimihiro Yamashita 《Journal of the American Ceramic Society》2000,83(11):2884-2886
The formation process of Ba2 La8 (SiO4 )6 O2 was clarified using thermogravimetry–differential thermal analysis (TG-DTA) and a high-temperature powder X-ray diffraction (HT-XRD) method. Phase changes identified from the HT-XRD data surprisingly corresponded to the weight loss and/or endothermic peaks observed in the TG-DTA curves. Raw material with the composition Ba2 La8 (SiO4 )6 O2 was completely reacted at 1400°C and produced only an apatite-type compound without a secondary phase. Moreover, the synthesis of Ba2+ x La8− x (SiO4 )6 O2−δ crystals with x = 0–2 was attempted using a solid-state reaction. 相似文献
84.
Hiroaki Okamoto 《Journal of Phase Equilibria and Diffusion》2013,34(3):251-263
Recent literature on Cs-In, Cs-K, Cs-Rb, Eu-In, Ho-Mn, K-Rb, Li-Mg, Mg-Nd, Mg-Zn, Mn-Sm, O-Sb, and Si-Sr phase diagrams is reviewed in this article in order to update the 1990 compilation Binary Alloy Phase Diagrams, 2nd edition, by T.B. Massalski, et al. For some systems reaction tables and crystal structure data have been included, as well. Diagrams have been checked for consistency with rules for phase diagram construction and modified when necessary. In addition, diagrams needing more work have been identified. 相似文献
85.
Hiromichi Gima Jun Adachi Masahito Katayama Hiroaki Muta Masayoshi Uno Shinsuke Yamanaka 《Journal of Nuclear Materials》2009,389(1):155-159
We prepared polycrystalline pellets of (U,Y)O2, containing YO1.5 up to 11 mol.%. We performed indentation tests on the pellets, and evaluated the Young’s modulus and hardness. We measured the heat capacity and the thermal diffusivity, and evaluated the thermal conductivity. We succeeded in evaluating the effect of Y content on the thermophysical properties of (U,Y)O2. We revealed that the Young’s modulus, hardness, and thermal conductivity of (U,Y)O2 decreased with increasing the Y content. 相似文献
86.
Takashi MINAMI Shohei ARAI Naoki KENMOCHI Hiroaki YASHIRO Chihiro TAKAHASHI Shinji KOBAYASHI Tohru MIZUUCHI Shinsuke OHSHIMA Satoshi YAMAMOTO Hiroyuki OKADA Kazunobu NAGASAKI Yuji NAKAMURA Kiyoshi HANATANI Shigeru KONOSHIMA Fumimichi SANO 《等离子体科学和技术》2013,(3):240-243
A new high repetition rate Nd:YAG Thomson scattering system is developed for the Heliotron J helical device.A main purpose of installing the new system is the temporal evolution measurement of a plasma profile for improved confinement physics such as the edge transport barrier (H-mode) or the internal transport barrier of the helical plasma.The system has 25 spatial points with ~10mm resolution.Two high repetition Nd:YAG lasers (>550mJ@ 50Hz) realize the measurement of the time evolution of the plasma profile with ~10ms time intervals.Scattered light is collected by a large concave mirror (D=800 mm,f/2.25) with a solid angle of ~100 mstr and transferred to interference filter polychromators by optical fiber bundles in a staircase form.The signal is amplified by newly designed fast preamplifiers with DC and AC output,which reduces the low frequency background noise.The signals are digitized with a multi-event QDC,fast gated integrators.The data acquisition is performed by a VME-based system operated by the CINOS. 相似文献
87.
Xuan Lian Hiroaki Miyoshi Yuki Mitsuya Kenji Shimazoe 《Journal of Nuclear Science and Technology》2018,55(7):805-811
The liquid crystal display (LCD) technology allows several simple circuits to be built using thin film transistors, thus making fabrication of compact, integrated, large-area, and low-cost micro-pattern gaseous detectors possible. In this work, a single-grid-type micro-strip gas chamber (S-MSGC) using transparent electrodes based on the LCD technology was fabricated and successfully operated in several gas mixtures. The detector was coupled with a multi-pixel photon counter to detect an optical signal through the transparent substrate in Ar/CF4 gas. Both electrical and optical signals were measured and the light yield of the detector was acquired. Successful operation of the S-MSGC can be considered the very important first step for development of the next target of integrated devices. 相似文献
88.
Sang Jun Yoon Jae Goo Lee Hideo Tajima Akihiro Yamasaki Fumio Kiyono Tetsuya Nakazato Hiroaki Tao 《Journal of Industrial and Engineering Chemistry》2010,16(3):350-354
Extractions of five kinds of lanthanide metal ions by bis(2-ethylhexyl)phosphoric acid (DEHPA) with [1-Cn-3-methylimidazolium][PF6](Cn = C2, C4) or [1-butyl-4-methylpyridinium][PF6] were carried out under various DEHPA and HNO3 concentrations from 0 to 1 M and under different temperature conditions from 298 to 333 K. These results were compared with those using the conventional organic solvent, hexane, in terms of their distribution coefficient values. Under all of the conditions in this study, the ionic liquid system shows more than three times greater extractability for lanthanide compared to when hexane was used. The distribution coefficient of lanthanide ions decreased as the length of the alkyl chain increased from the ethyl to the butyl. In addition, the imidazolium cation generally shows a higher distribution coefficient compared to the pyridinium cation in an ionic liquid. The concentration ratio of lanthanides and DEHPA resulted in an extraction affinity transition for lanthanides. Also evaluated in this study were issues related to the selectivity associated with the lanthanide mixture and the dependency of the ionic radius during lanthanide extraction. 相似文献
89.
Input data to a numerical model are not necessarily well known. Uncertainties may exist both in material properties and in the geometry of the device. They can be due, for instance, to ageing or imperfections in the manufacturing process. Input data can be modelled as random variables leading to a stochastic model. In electromagnetism, this leads to solution of a stochastic partial differential equation system. The solution can be approximated by a linear combination of basis functions rising from the tensorial product of the basis functions used to discretize the space (nodal shape function for example) and basis functions used to discretize the random dimension (a polynomial chaos expansion for example). Some methods (SSFEM, collocation) have been proposed in the literature to calculate such approximation. The issue is then how to compare the different approaches in an objective way. One solution is to use an appropriate a posteriori numerical error estimator. In this paper, we present an error estimator based on the constitutive relation error in electrokinetics, which allows the calculation of the distance between an average solution and the unknown exact solution. The method of calculation of the error is detailed in this paper from two solutions that satisfy the two equilibrium equations. In an example, we compare two different approximations (Legendre and Hermite polynomial chaos expansions) for the random dimension using the proposed error estimator. In addition, we show how to choose the appropriate order for the polynomial chaos expansion for the proposed error estimator. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
90.