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排序方式: 共有838条查询结果,搜索用时 31 毫秒
171.
172.
Ke Fang Yuki Murakami Seiji Kanda Takaki Shimono Anh Tuan Dang Mitsuaki Ono Toshimasa Nishiyama 《International journal of molecular sciences》2022,23(14)
Osteoporosis is a common bone disease, particularly in menopausal women. Herein, we screened four Kampo medicines (Unkeito (UKT), Kamishoyosan (KSS), Kamikihito (KKT), and Ninjinyoeito (NYT)), frequently used to treat menopausal syndromes, for their effects on receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast differentiation in RAW 264 cells. Considering that UKT exhibited the most potent effect, we examined its effect on RANKL-induced osteoclastogenesis, the induction of osteoclast apoptosis, and the mechanisms underlying its effects. UKT inhibits RANKL-induced osteoclast differentiation in the early stage and decreases osteoclast-related genes, including tartrate-resistant acid phosphatase (Trap), dendritic cell-specific transmembrane protein (Dcstamp), matrix metalloproteinase-9 (Mmp9), and cathepsin K (Ctsk). Specifically, UKT inhibits the nuclear factor of activated T cells 1 (NFATc1), which is essential for osteoclastogenesis. UKT increases Bcl6, which antagonizes NFATc1 and Dc-stamp, thereby blocking the progression of osteoclasts to maturation. UKT also decreased nuclear translocation by downregulating the activity of p65/NF-κB. In addition, UKT enhances mononuclear osteoclast apoptosis via activation of caspase-3. Herein, we demonstrate that UKT suppresses RANKL-mediated osteoclastogenesis via the Blimp1–Bcl6 and NF-κB signaling pathways and enhances mononuclear osteoclast apoptosis. Furthermore, UKT prevents bone loss in OVX mice. Thus, UKT might be a potential therapeutic agent for postmenopausal osteoporosis. 相似文献
173.
Anh Tuan Hoang Van Viet Pham 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(5):611-625
Vegetable oils are always considered as the potential sources since the renewable and alternative fuels have been being paid attention by all countries in the world based on the strategies of the environmental pollution reduction. The aim of this experimental study is to evaluate the effects of as-used fuels on emission characteristics, deposit formation, and lubricating oil (LO) degradation of a 4 stroke-4 cylinder diesel engine running on preheated vegetable oil and diesel oil. All tests were conducted under 2000 rpm of engine speed, and 80hp of power within different periods of time depending on the test purposes. The ICP-MS analyzer was used to measure the LO quality through the parameters of kinematic viscosity, density, and metal concentrations on the basis of ASTM D5185-09 standard after every 25 hours of the test duration. Meanwhile, the emission characteristics were tested by an exhaust analyzer after every 50 hours, and deposit formation on piston crown and piston groove was evaluated by the assistance of Scanning electron microscopy (SEM) after 300 hours of the test. Besides, the thorough analysis related to the relationship between deposit formation, the degradation of the engine LO and emission characteristics were presented. 相似文献
174.
Wireless Networks - This article addresses the problem of secure communication in an unmanned aerial vehicle (UAV)-aided wireless communication system in which a source sends confidential messages... 相似文献
175.
Nguyen Huy Tuan Danh Hua Quoc Nam Thi Minh Nhat Vo 《Computers & Mathematics with Applications》2019,77(1):15-33
We study for the first time the backward problem for nonlocal nonlinear boundary value problem of Kirchhoff’s model of parabolic type. First, we show that the problem is severely ill-posed in the sense of Hadamard. We propose two methods: the Fourier truncation method for stabilizing the problem with homogeneous source and the quasi-reversibility method for regularizing the problem with nonlinear source. Under some priori assumptions on the exact solution, we establish some stability estimates in the norm. 相似文献
176.
Tuan Kiet Tran Prasun Kumar Hak-Ryul Kim Ching T. Hou Beom Soo Kim 《Journal of the American Oil Chemists' Society》2019,96(6):715-726
Bio-based new polyurethanes (PU) were synthesized from microbially converted castor oil. Castor oil was used as a raw material to synthesize 7,10,12-trihydroxy-8(E)-octadecenoic acid (TOD) by the strain Pseudomonas aeruginosa PR3. Subsequently, hexamethylene diisocyanate (HMDI) was used in different ratios and reacted with TOD to produce new PU. Fourier transform-infrared spectroscopy, nuclear magnetic resonance spectroscopy, and gas chromatography/mass spectrometry were used to confirm the identity of TOD. Differential scanning calorimetry, thermogravimetric analysis, and tensile property testing were used to investigate the thermal and mechanical properties of PU. PU synthesized based on TOD had a tensile strength of 45.4 MPa with low elongation at break of 8.16% at an isocyanate/hydroxyl ratio of 2.0. To modify the properties of PU, TOD was blended separately with polyethylene glycol or polycaprolactone diol at different weight ratios before reacting with HMDI. The modified polymer showed improved thermal stability and comparatively higher elongation at break. This is the first study demonstrating the conversion of castor oil into TOD that can be used stand alone or as a blend for PU synthesis. 相似文献
177.
Hasan Md. Rabiul Goodbody Carlene Nguyen Tuan Thanh Karacolak Tutku 《Microsystem Technologies》2020,26(8):2703-2713
Microsystem Technologies - For having adapted to the various national spectral regulatory authorities, it is preferred to have a design of antenna that can be easily modified to be compatible with... 相似文献
178.
Video streaming is often carried out by congestion controlled transport protocols to preserve network sustainability. However, the success of the growth of such non-live video flows is linked to the user quality of experience. Thus, one possible solution is to deploy complex quality of service systems inside the core network. Another possibility would be to keep the end-to-end principle while making aware transport protocols of video quality rather than throughput. The objective of this article is to investigate the latter by proposing a novel transport mechanism which targets video quality fairness among video flows. Our proposal, called VIRAL for virtual rate-quality curve, allows congestion controlled transport protocols to provide fairness in terms of both throughput and video quality. VIRAL is compliant with any rate-based congestion control mechanisms that enable a smooth sending rate for multimedia applications. Implemented inside TFRC a TCP-friendly protocol, we show that VIRAL enables both intra-fairness between video flows in terms of video quality and inter-fairness in terms of throughput between TCP and video flows. 相似文献
179.
Hao-Yu Chang Ying-Cen Chen Wei-Hsing Tuan Sseu-Pei Hwang Li-Kwan Chang Chia-Jung Wu Chih-Yi Chen Po-Liang Lai 《Ceramics International》2021,47(6):7805-7813
Synthetic bone graft has gained considerable attention because of an increase in the aged population. In the present study, a biphasic bone graft composed of hydroxyapatite (HAp) and calcium sulfate (CS) is prepared using a gel-foaming technique. The gel is prepared at a temperature as low as 35 °C; many pores are introduced into the gel through an agitation process. The foamed gel can be cut into any shape and size. After sintering, the porosity of the biphasic bone graft is approximately 70%. Depending on the HAp/CS ratio, the amount of macropores and micropores can be tailored. The macropores of approximately 130 μm diameter are interconnected with each other through openings of 40 μm size. The biphasic bone graft exhibits no cytotoxicity; preosteoblast cells can adhere and proliferate on the surface of the fabricated bone graft. However, migration of these cells into the bone graft is considerably limited in the in vitro study. When the biphasic bone graft is implanted into the distal femur of rats, with the combined effect of osteoblast and osteoclast cells, more than 90% of the bone graft is degraded after 3 months. New trabeculae bone and bone marrow are observed within the bone defect. The HAp/CS composite can thus be used as degradable bone grafts. 相似文献
180.
A computer model has been written to predict the consumption of refrigerants for vehicle air conditioning in China, India, South Korea and South-East Asia, their effect on ozone depletion and global warming, and their costs. A simple logarithmic relationship between per capita income and population growth rate is assumed. Correlations between vehicle ownership and air-conditioning usage are obtained from worldwide data. Both synthetic HFC (134a) and natural (hydrocarbons) refrigerants are considered. Sample calculations, assuming reasonable economic growth rates, predict that the use of hydrocarbons will lead to significant reductions in global warming potential and large savings in cost. The synthetic HFC option will incur costs exceeding a billion US dollars per year after the year 2005. 相似文献