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排序方式: 共有702条查询结果,搜索用时 692 毫秒
1.
Akiko Suzuki Mina Minamide Chihiro Iwaya Kenichi Ogata Junichi Iwata 《International journal of molecular sciences》2020,21(23)
Carbohydrates, fats, and proteins are the underlying energy sources for animals and are catabolized through specific biochemical cascades involving numerous enzymes. The catabolites and metabolites in these metabolic pathways are crucial for many cellular functions; therefore, an imbalance and/or dysregulation of these pathways causes cellular dysfunction, resulting in various metabolic diseases. Bone, a highly mineralized organ that serves as a skeleton of the body, undergoes continuous active turnover, which is required for the maintenance of healthy bony components through the deposition and resorption of bone matrix and minerals. This highly coordinated event is regulated throughout life by bone cells such as osteoblasts, osteoclasts, and osteocytes, and requires synchronized activities from different metabolic pathways. Here, we aim to provide a comprehensive review of the cellular metabolism involved in bone development and homeostasis, as revealed by mouse genetic studies. 相似文献
2.
Keita Ikeue Shingo Ando Tomohiro Mitsuyama Yusuke Ohta Keishi Arayama Akiko Tsutsumi Masato Machida 《Topics in Catalysis》2008,47(3-4):175-180
Lanthanide-based oxysulfides and sulfide, LnTaO3.5S0.5, Ln10OS14 (Ln = La, Pr, Nd, Sm) and La4In5S13, were successively synthesized by sulfurization in a flowing H2S. The sulfurization decreased the band-gap energies from >4 eV to <3eV, because of the formation of occupied S3p orbitals
on the top of valence band. In accordance with the small band gap, the H2 evolution from a 0.01 M Na2S and 0.01 M Na2SO3 solution system was observed under irradiation of light up to >500 nm. The rate of H2 evolution under light irradiation of >500 nm increased in the order of Ni/LaTaO3.5S0.5 < Ru/La10OS14 < Pt/La4In5S13. 相似文献
3.
A focus on the importance of leisure in the development of student nurses has been neglected in the 1990s. This study considers 444 prospective nurses on conventional, diploma and degree courses in two areas of England. It examines their activities associated with socializing, their social support networks and their use of clubs, sports and hobbies before entering nursing. It is evident that students enter nurse training with a wide variety of leisure experiences. Changing recruitment patterns and the structure of nurse training has an effect on the leisure needs of prospective nurses which must be addressed. 相似文献
4.
5.
Rui Morimoto Chisato Yokomori Akiko Kikkawa Akira Izumi Hideki Matsumura 《Thin solid films》2003,430(1-2):230-235
In this paper, bulk-Si metal–oxide–semiconductor field effect transistors (MOSFETs) are fabricated using the catalytic chemical vapor deposition (Cat-CVD) method as an alternative technology to the conventional high-temperature thermal chemical vapor deposition. Particularly, formation of low-resistivity phosphorus (P)-doped poly-Si films is attempted by using Cat-CVD-deposited amorphous silicon (a-Si) films and successive rapid thermal annealing (RTA) of them. Even after RTA processes, neither peeling nor bubbling are observed, since hydrogen contents in Cat-CVD a-Si films can be as low as 1.1%. Both the crystallization and low resistivity of 0.004 Ω·cm are realized by RTA at 1000 °C for only 5 s. It is also revealed that Cat-CVD SiNx films prepared at 250 °C show excellent oxidation resistance, when the thickness of films is larger than approximately 10 nm for wet O2 oxidation at 1100 °C. It is found that the thickness required to stop oxygen penetration is equivalent to that for thermal CVD SiNx prepared at 750 °C. Finally, complementary MOSFETs (CMOSs) of single-crystalline Si were fabricated by using Cat-CVD poly-Si for gate electrodes and SiNx films for masks of local oxidation of silicon (LOCOS). At 3.3 V operation, less than 1.0 pA μm−1 of OFF leakage current and ON/OFF ratio of 107–108 are realized, i.e. the devices can operate similarly to conventional thermal CVD process. 相似文献
6.
Masaaki Suzuki Yoshihisa Hasegawa Masayuki Aizawa Yoshinori Nakata Takeshi Okutani Kohei Uosaki 《Journal of the American Ceramic Society》1995,78(1):83-89
The structure of silicon carbide–silicon nitride (SiC–Si3 N4 ) composite particles synthesized using a CO2 laser was studied by magic angle spinning nuclear magnetic resonance (MAS-NMR) and electron spin resonance (ESR). The structure around Si atoms changed by introducing N. C atoms around Si were substituted by N atoms, and N-rich configurations around Si atoms increased stepwise as the N content increased. The low N content composite particles consisted of mainly SiC phase containing dissolved N. N atoms were partly present in β-SiC microcrystal and partly in the grain boundary layer in the particle. N atoms were tetrahedrally surrounded by four Si atoms in β-SiC microcrystal and were trivalent state bonded to three Si atoms in the grain boundary layer. The high N content particles consisted of SiC, Si3 N4 , and amorphous phases, whose amount depended on N content. 相似文献
7.
Photo-excitable electrodes were prepared by incorporating magnesium chlorophyll (MgChl) or manganese chlorophyll (MnChl) into the thin layer of such liquid cyrstals as N-(p-methoxybenzylidene)-p-butylaniline (MBBA) and 4′-heptyl-4-cyanobiphenyl (HCB), being attached to the platinum surface. The MgChl—MBBA electrode gave the positive photo-induced potential shift in an acidic solution. In sharp contrast, the negative photo-induced potential shift was developed by the MnChl—HCB electrode in an alkaline solution. The involvement of a liquid crystal prominently enhanced the photo-response of the immobilized chlorophylls. The photoelectrochemical energy conversion system modeled on the photosynthetic process was assembled by employing the MgChl—MBBA and the MnChl—HCB electrodes as a cathode and an anode, respectively. The photocurrent derived from the system was concluded to result from the decomposition of water, since an evidence for the molecular oxygen evolution at the MnChl—HCB electrode was obtained. Furthermore, the incorporation of β-carotene was found to markedly enhance the stability of the MnChl—HCB electrode. 相似文献
8.
Masahiro Tajima Miki Niwa Yasushi Fujii Yutaka Koinuma Reiji Aizawa Satoshi Kushiyama Satoru Kobayashi Koichi Mizuno Hideo Ohuˆchi 《Applied catalysis. B, Environmental》1997,12(4):1418
The decomposition of chlorofluorocarbons (CFCs) in the presence of water was examined over a variety of solid acid catalysts. The TiO2ZrO2 catalyst was found to have the highest activity and longest life among the catalysts examined. The activity of the TiO2ZrO2 catalysts depended upon the content of TiO2. At the contents of TiO2 from 58 to 90 mole%, the TiO2ZrO2 catalysts exhibited high activity, and these catalysts were proven to contain TiZrO4 crystal. From the study of the XRD peak intensity of the TiZrO4 crystal, it was highest on the TZ-58 which contained 58 mole% of TiO2, and decreased with increasing the content of TiO2. Furthermore, the conversion of CFC113 measured at 673 K was highest at TZ-58, and decreased gradually with increasing TiO2 content. Therefore, the TiZrO4 crystal influences the activity of decomposition of CFC113. However, the TiO2ZrO2 catalyst was gradually deactivated during the reaction due to the elimination of titanium atoms. A good relationship was found between the activity on TiO2ZrO2 catalyst and bond energy of CCl in the compounds of chlorofluorocarbons and hydrochlorocarbons, suggesting that the rate controlling step was the cleavage of CCl bond. 相似文献
9.
Masanori Yamazaki Akiko Nishijima Kazuko Ikeda Shoji Ichihara 《Polymer Bulletin》2004,52(3-4):267-274
Summary
In order to obtain materials with nanopores which will be applicable for many fields, the structures of the cured blends of phenolic resin (PhN), poly(methyl methacrylate) (PMMA) and curing agent were studied. After PMMA was extracted from cured blends, the structures of cured phenolic resins were observed with SEM. As a results, it was found that nanosized continuous pore structures were formed in extremely wide composition region if curing temperature was high. 相似文献
10.
ABSTRACT Preparation of poly(thiophene-alt-pyrrole bearing mesogen) was carried out with Migita–Kosugi–Stille coupling type polycondensation with an aid of Pd(0) complex catalyst. The resultant polymer shows lyotropic liquid crystallinity with good film-forming property. The smectic fan-shaped texture is maintained after completion of evaporation of solvent from the polymer solution. The cast film having liquid crystal (LC) order shows light emission function upon irradiation of excitation light at 460 nm. The polymer shows LC domain emission. Mechanical orientation allows to yield LC domain aligned film with band structure. Chiral mesogenic side chain induces π-conjugated main chain helicity from distance in molecular level. 相似文献