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排序方式: 共有1134条查询结果,搜索用时 15 毫秒
1.
Takashi Ohnishi Yuki Ogawa Kota Suda Miki Komatsu Satoko Matsumoto Harmon Mitsuru Asukai Masahiko Takahata Norimasa Iwasaki Akio Minami 《International journal of molecular sciences》2021,22(9)
Pyogenic spondylodiscitis can cause severe osteolytic and destructive lesions in the spine. Elderly or immunocompromised individuals are particularly susceptible to infectious diseases; specifically, infections in the spine can impair the ability of the spine to support the trunk, causing patients to be bedridden, which can also severely affect the physical condition of patients. Although treatments for osteoporosis have been well studied, treatments for bone loss secondary to infection remain to be elucidated because they have pathological manifestations that are similar to but distinct from those of osteoporosis. Recently, we encountered a patient with severely osteolytic pyogenic spondylodiscitis who was treated with romosozumab and exhibited enhanced bone formation. Romosozumab stimulated canonical Wnt/β-catenin signaling, causing robust bone formation and the inhibition of bone resorption, which exceeded the bone loss secondary to infection. Bone loss due to infections involves the suppression of osteoblastogenesis by osteoblast apoptosis, which is induced by the nuclear factor-κB and mitogen-activated protein kinase pathways, and osteoclastogenesis with the receptor activator of the nuclear factor-κB ligand-receptor combination and subsequent activation of the nuclear factor of activated T cells cytoplasmic 1 and c-Fos. In this study, we review and discuss the molecular mechanisms of bone loss secondary to infection and analyze the efficacy of the medications for osteoporosis, focusing on romosozumab, teriparatide, denosumab, and bisphosphonates, in treating this pathological condition. 相似文献
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Oda K. Ohue E. Suzumura I. Hayami R. Kodama A. Shimamoto H. Washio K. 《Electron Devices, IEEE Transactions on》2003,50(11):2213-2220
Si/sub 1-x-y/Ge/sub x/C/sub y/ selective epitaxial growth (SEG) was performed by cold-wall, ultrahigh-vacuum chemical vapor deposition, and the effects of incorporating C on the crystallinity of Si/sub 1-x-y/Ge/sub x/C/sub y/ layers and the performance of a self-aligned SiGeC heterojunction bipolar transistor (HBT) were evaluated. A Si/sub 1-x-y/Ge/sub x/C/sub y/ layer with good crystallinity was obtained by optimizing the growth conditions. Device performance was significantly improved by incorporating C, as a result of applying Si/sub 1-x-y/Ge/sub x/C/sub y/ SEG to form the base of a self-aligned HBT. Fluctuations in device performance were suppressed by alleviating the lattice strain. Furthermore, since the B out diffusion could be suppressed by incorporating C, the cutoff frequency was able to be increased with almost the same base resistance. A maximum oscillation frequency of 174 GHz and an emitter coupled logic gate-delay time of 5.65 ps were obtained at a C content of 0.4%, which shows promise for future ultrahigh-speed communication systems. 相似文献
4.
Studies static-state feedback control of discrete-event systems under partial observation. The authors present a necessary and sufficient condition for the existence of a static-state feedback controller. A static controller is a special case of a dynamic controller studied by Kumar et al. The authors' condition, however, has computational advantage in contrast to those obtained by Kumar et al. The authors also present a necessary and sufficient condition under which the modular feedback synthesis is possible 相似文献
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In vitro transdifferentiation of retinal pigmented epithelial cells of the chick embryo into lens cells can be markedly enhanced by culture in the presence of testicular hyaluronidase and phenylthiourea. Since the commercial preparations of hyaluronidase that had previously been used were very crude, a search for the actual effective molecule(s) enhancing lens transdifferentiation was conducted. First, we purified the enzyme and tested the effect of the purified hyaluronidase. Highly purified hyaluronidase itself did not enhance lens transdifferentiation. The crude hyaluronidase was then separated according to affinity with heparin, considering the possibility that the fibroblast growth factor (FGF) is contained in the crude hyaluronidase. Transdifferentiation-enhancing activity was detected in the fraction which was bound to heparin and eluted with 2 M NaCl, where no hyaluronate-degrading activity existed. Analysis of the fraction by SDS-PAGE revealed the existence of an 18 kDa protein whose NH2-terminal sequence was identical to that of basic FGF. The basic FGF derived from bovine brain also enhanced lens transdifferentiation of pigmented epithelial cells. These findings suggest that basic FGF must play a major role in enhancing transdifferentiation of pigmented epithelial cells to lens cells. 相似文献
8.
S Fukumoto M Suzawa Y Takeuchi Y Kodama K Nakayama E Ogata T Matsumoto T Fujita 《Canadian Metallurgical Quarterly》1996,81(7):2554-2558
9.
Keishi Sakamoto Atsushi Kasugai Masaki Tsuneoka Koji Takahashi Yukiharu Ikeda Tsuyoshi Imai Takashi Nagashima Mitsuru Ohta Tsuyoshi Kariya Kenichi Hayashi Yoshika Mitsunaka Yosuke Hirata Yasuyuki Itoh Yukio Okazaki 《Journal of Infrared, Millimeter and Terahertz Waves》1997,18(9):1637-1654
A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at PRF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at PRF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window. 相似文献
10.
N. Murayama M. Awano Y. Kodama S. Sakaguchi F. Wakai 《Journal of Materials Science》1992,27(13):3642-3644
Bi0.85Pb0.15Sr0.8CaCu1.4O
y
superconductor was quenched to room temperature after annealing at several temperatures in air. From the initial magnetization curve measurement for the annealed samples, it was found that the volume fraction of superconducting phases of the sample annealed at 650°C greatly decreased. TEM observation revealed that a second phase often appeared in the grain-boundary region for the sample annealed at 700°C. The second phase was identified as Bi1Pb2Sr2.6Ca1.6O
y
by energy dispersive spectroscopy. 相似文献