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排序方式: 共有790条查询结果,搜索用时 421 毫秒
161.
Masahiro Hatasa Sumiko Yoshida Hirokazu Takahashi Kenichi Tanaka Yoshihito Kubotsu Yujin Ohsugi Takaharu Katagiri Takanori Iwata Sayaka Katagiri 《International journal of molecular sciences》2021,22(7)
Periodontal disease is an inflammatory disease caused by pathogenic oral microorganisms that leads to the destruction of alveolar bone and connective tissues around the teeth. Although many studies have shown that periodontal disease is a risk factor for systemic diseases, such as type 2 diabetes and cardiovascular diseases, the relationship between nonalcoholic fatty liver disease (NAFLD) and periodontal disease has not yet been clarified. Thus, the purpose of this review was to reveal the relationship between NAFLD and periodontal disease based on epidemiological studies, basic research, and immunology. Many cross-sectional and prospective epidemiological studies have indicated that periodontal disease is a risk factor for NAFLD. An in vivo animal model revealed that infection with periodontopathic bacteria accelerates the progression of NAFLD accompanied by enhanced steatosis. Moreover, the detection of periodontopathic bacteria in the liver may demonstrate that the bacteria have a direct impact on NAFLD. Furthermore, Porphyromonas gingivalis lipopolysaccharide induces inflammation and accumulation of intracellular lipids in hepatocytes. Th17 may be a key molecule for explaining the relationship between periodontal disease and NAFLD. In this review, we attempted to establish that oral health is essential for systemic health, especially in patients with NAFLD. 相似文献
162.
Computational Visual Media - In many-light rendering, a variety of visual and illumination effects, including anti-aliasing, depth of field, volumetric scattering, and subsurface scattering, are... 相似文献
163.
K Matsumoto K Akagi M Abekura Y Maeda M Kitagawa H Ryujin N Iwasa 《Canadian Metallurgical Quarterly》1997,37(11):849-851
A 45-year-old male presented with sudden onset of severe headache. Computed tomography and magnetic resonance imaging demonstrated an irregularly enhanced suprasellar mass with intratumoral and subarachnoid hemorrhage. The mass was removed in two operations. Histological examination of the tumor revealed pilocytic astrocytoma. The relatively rich vascularity and perivascular tumor cell proliferation observed in this benign lesion were probably the causes of this extremely rare association. 相似文献
164.
A new-type single balanced mixer which satisfies the specifications of E-TACS (extended total access communication system) ultra-wideband cellular radio has been developed. The circuit is constructed with a single ferrite hybrid coil, two GaAs FETs and an IF coil, which provide good spurious-response characteristics for arbitrary intermediate frequencies. Miniaturisation of the front-end module is achieved by using SAW filters and the above mixer.<> 相似文献
165.
The objective of this paper is to develop a computer-aided optimal planning method for designing a marine heat and power generation plant which is composed of combining Diesel and turbogenerators, an exhaust gas economizer, auxiliary boilers and so forth. As there exist many alternative combinations concerning generators and boilers in constructing the abovementioned plant, it is important to determine the plant construction properly by selecting total numbers and scales of respective generators and boilers so as to optimize the long-term economy of the plant. In this planning method, several design conditions are first set which are necessary for the planning of the objective plant, i.e. several patterns of ship's operational condition are set first, and both energy demands and steam output from an exhaust gas economizer are estimated for each pattern. Next, setting an alternative plant composed of combining generators and boilers adequately, the optimal operational policy for each pattern is determined by minimizing the fuel cost under several physical constraints based on linear and quadratic programming methods. Considering the results obtained above hierarchically, annual capital and operational costs of each plant are calculated, and the best plant construction is lastly determined by comparing the economy of all alternative plants. A numerical study has been carried out on a plant of a high speed container ship actually planned, and it is ascertained that to find the best construction of the plant the optimal planning method proposed here is advantageous compared with the conventional trial and error method. 相似文献
166.
Sub-boundaries in3He and4He single crystal and their migration below 1K observed by X-ray topography
Tetsuo Nakajima Joji Ohta Ichiro Yonenaga Hirokazu Koizumi Izumi Iwasa Haruhiko Suzuki Takayoshi Suzuki Hideji Suzuki 《Journal of Low Temperature Physics》1995,101(3-4):701-706
The observation of alterations in crystal structure at ultra-low temperatures by X-ray diffraction, made possible by the realization of synchrotron radiation use after a quarter of this century, plays an important role in obtaining an understanding of the base structure of solids. For that, two types of3He-4He dilution refrigerators with a modified version of the top-loading facilities were installed at the BL-3C2 and 6C1 stations of the Photon Factory. In BL-3C2, the behaviors of lattice defects in solid helium have been studied by X-ray topography. In this note, the migrations of sub-boundaries in3He and4He single-crystals are reported as being the result of an annealing effect. After annealing hcp4He single crystals for 80min at 0.5K, no change in crystallographic orientations could be easily observed from white SR X-ray topographs. In the same type topographs of bcc3He single crystals after annealing for several hours at 03K, migration of sub-boundaries were conspicuously discerned. 相似文献
167.
Hirokazu Yoshizawa Gabor C. Temes 《Analog Integrated Circuits and Signal Processing》2006,48(3):267-270
This paper describes a high-precision switched-capacitor (SC) track-and-hold amplifier (THA) stage. It uses a novel continuous-time
correlated double sampling (CDS) scheme to desensitize the operation to amplifier imperfections. Unlike earlier predictive-CDS
THAs, the circuit does not need a sample-and-held input signal for its operation. During the tracking period, an auxiliary
continuous-time signal path is established, which predicts the output voltage during the holding period. This allows accurate
operation even for low amplifier gains and large offsets over a wide input frequency range. Extensive simulations were performed
to compare the performance of the proposed THA with earlier circuits utilizing CDS. The results verify that its operation
is far more robust than that of any previously described THA. 相似文献
168.
J Tsuchiyama T Yoshino M Mori E Kondoh T Oka T Akagi A Hiraki H Nakayama A Shibuya Y Ma T Kawabata S Okada M Harada 《Canadian Metallurgical Quarterly》1998,92(4):1374-1383
A novel cell line was established from a patient with a leukemic-state nasal angiocentric natural killer (NK) cell lymphoma with systemic skin infiltration. The morphology of the leukemic cells was large-granular-lymphocyte (LGL), and their immunophenotype was CD2+, CD3-, CD5+, CD7+, CD16-, CD56+, and CD57-. The presence of Epstein-Barr viral (EBV) genome was shown in specimens from the patient's nose, skin, and peripheral blood by in situ hybridization using an EBV-encoded small RNA-1 probe or by Southern blotting using a terminal-repeat probe of the EBV genome. Leukemic cells were cocultured with a mouse stromal cell line (SPY3-2) in the presence of 100 U/mL recombinant human interleukin-2 and a novel stromal cell-independent cell line, NK-YS, was established. The NK-YS cells showed LGL morphology and expressed surface CD2, CD5, CD7, CD25, CD56, and CD95. The NK-YS cells retained cytotoxicity against K562 and Jurkat cells. A Southern blotting using a terminal-repeat probe of EBV showed that NK-YS and fresh leukemic cells had a clonal EBV genome, whereas the T-cell receptor beta and gamma chain genes of NK-YS were not rearranged. In an immunocytochemical analysis, the NK-YS cells showed a type-II latent infection of EBV. The NK-YS cells preserved the original characteristics of NK cell lymphoma/leukemia and will be a useful tool for the study of biological characteristics of EBV-associated nasal angiocentric NK cell lymphoma/leukemia. 相似文献
169.
S Oho A Ishizawa K Koike T Kobayashi T Nakanishi K Momma T Ino K Nishimoto M Ohkubo Y Ono T Kamiya T Akagi H Kato 《Canadian Metallurgical Quarterly》1998,62(7):489-493
A comparison of two methods: analytical and calculation on an estimation of dietary intakes of nitrate and nitrite from six different types of general hospital diets was studied. Studies were performed in the winter season of 1996-1997. It was found that the mean daily intake of nitrates was 85 mg per person in the analytical method, and 65 mg per person in the calculated method. The estimation of average dietary intakes of nitrite was adequate: 1.67 mg per person (the analytical method) and 1.18 mg per person (the calculated method). The main source of nitrates were vegetables, whereas the main source of nitrites was meat and meat-containing products. We suggest that the different methodologies, analytical and calculation methods, for measuring dietary intakes of nitrate and nitrite from diets make it possible to make direct comparisons of intakes. 相似文献
170.
This paper proposes a nonlinear circuit that generates chaotic oscillations. The proposed nonlinear circuit includes a nonlinear capacitor and a nonlinear inductor by using Generalized Impedance Converters. Both computational experiments and experiments on real circuits show that the region for chaotic oscillation is very wide, demonstrating that the proposed circuit is effective as a chaos generator. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 35–42, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10361 相似文献