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61.
Porous Titania Ceramic Prepared by Mimicking Silicified Wood   总被引:6,自引:0,他引:6  
A porous titania ceramic with a woodlike microstructure that was analogous to silicified wood was prepared. The production of "titanified wood" was performed using the following process: (i) introduction of titanium tetraisopropoxide into wood materials via vacuum infiltration, (ii) hydrolysis of the titanium tetraisopropoxide in the cell structure to form a titania gel, and (iii) firing at a temperature of 600°–1400°C in air. The resulting titania ceramic had the same external and internal forms of the original wood.  相似文献   
62.
Specific inhibitors of diacylglycerol kinase (DGK) ζ can be promising anticancer medications via the activation of cancer immunity. Although the detection of cellular activities of target enzymes is essential for drug screening in addition to in vitro assays, it is difficult to detect the activity of DGKζ in cells. In the present study, we generated AcGFP-DGKζ cDNA with a consensus N-myristoylation sequence at the 5′ end (Myr-AcGFP-DGKζ) to target DGKζ to membranes. Using liquid chromatography (LC)-tandem mass spectrometry (MS/MS) (LC–MS/MS), we showed that Myr-AcGFP-DGKζ, but not AcGFP-DGKζ without the myristoylation sequence, substantially augmented the levels of several phosphatidic acid (PtdOH) species. In contrast to Myr-AcGFP-DGKζ, its inactive mutant did not exhibit an increase in PtdOH production, indicating that the increase in PtdOH production was DGK activity-dependent. This method will be useful in chemical compound selection for the development of drugs targeting DGKζ and can be applicable to various soluble (nonmembrane bound) lipid-metabolizing enzymes, including other DGK isozymes.  相似文献   
63.
Fruiting-inducing activity and antifungal properties of lipid components in the phylum Annelida were examined. Some amphoteric cerebrosides carrying a phosphocholine group showed fruiting-inducing activity on Schizophyllum commune, and one of them possessed activity comparable to that of Sch II, the most potent substance known. Furthermore, alkyl lysophosphatidylcholines were found to have an inhibitory effect on the growth of phytopathogenic fungi, Alternaria kikuchiana and Phomopsis mali. The relationship between structure and biological activities is discussed.  相似文献   
64.
In interstitial lung diseases, deposition of extracellular matrix (ECM) in alveoli and degradation of ECM lead to pulmonary structural remodeling. The changes in ECM and the localization of matrix metalloproteinases (MMPs) and a tissue inhibitor of metalloproteinases (TIMP) in the lung tissues of patients with bronchiolitis obliterans organizing pneumonia (BOOP) and idiopathic pulmonary fibrosis (IPF) were investigated. Immunohistochemical analysis for the detection of fibronectin, collagen-I, -III, and -IV, smooth muscle actin, MMP-1 (interstitial collagenase), -2 (gelatinase A), and -9 (gelatinase B), and TIMP-2, and in situ hybridization for the detection of MMP-9 mRNA were performed. Western blotting of lung tissue homogenates was performed for MMP-2 and MMP-9. The gelatinolytic activities of the homogenates were also determined using gelatin zymography. Fibronectin and collagen-I, -III, and -IV were detected in the intra-alveolar fibrosis in addition to the interstitium of these diseases. MMP-1, MMP-2, MMP-9, and TIMP-2 were detected in the regenerated epithelial cells covering intra-alveolar fibrosis. Myofibroblasts in intra-alveolar fibrosis in BOOP showed predominant reaction for MMPs, and they ultrastructurally appeared to be phagocytosing collagen fibrils, and those of IPF showed a predominant reaction for TIMP-2. New vascularization in intra-alveolar fibrosis was exclusively observed in cases of BOOP, and the endothelial cells were positive for MMP-2. Western blotting showed the existence of a latent form of MMP-9 and latent and active forms of MMP-2, and gelatin zymography revealed that the ratio of active/latent forms of MMP-2 in BOOP is significantly larger than that in the control lungs. Predominant MMPs in BOOP may constitute the mechanism of reversibility of fibrotic changes in this disease. TIMP-2 in myofibroblasts in IPF may contribute to the stable ECM deposition and the irreversible pulmonary structural remodeling.  相似文献   
65.
Surveys on the Seikan Tunnel began in 1946. Survey items included a detailed geological survey of the land on both the Honshu and Hokkaido sides; the creation of an undersea topographical map based on echo sounding techniques; and a general study of the geological structure of the undersea portion, carried out by seismic prospecting. A detailed undersea geological map has been edited chiefly by dredging and sonic prospecting. Carrying out offshore survey proved rather difficult, however, due to the water depth in the Tsugaru Straits, the fast tidal currents and the adverse weather conditions. Nonetheless, the results of the survey generally agreed with the actual geological conditions in terms of geographical formation sequence, major structure distribution, etc. In addition, the survey results were particularly effective in presenting the major geological features of primary importance, while greatly assisting in choosing the most appropriate design and construction work that followed.  相似文献   
66.
The influence of several parameters on the fermentative production of nisin Z by Lactococcus lactis IO-1 was studied. Considerable attention has been focused on the relationship between the primary metabolite production of bacteriocin and lactate and cell growth, which has so far not been clarified in detail. Production of nisin Z was optimal at 30 degrees C and in the pH range 5.0-5.5. The addition of Ca2+ to the medium showed a stimulating effect on the production of nisin Z. A maximum activity of 3150 IU/ml was obtained during pH-controlled batch fermentation in the medium supplemented with 0.1 M CaCl2. It was about three times higher than that obtained under the optimal conditions for cell growth and lactic acid production.  相似文献   
67.
68.
The nucleation and growth of hydroxyapatite (HAp) crystals from solutions with and without Langmuir monolayers of stearic acid (SA) were investigated. The monolayers apparently enhanced the nucleation of HAp. Monolithic, filmlike polycrystalline HAp with preferred orientation of (00l) planes parallel to the monolayer interface was precipitated, while colloidal and powdery precipitation in the bulk solution was predominant in the absence of the monolayer. Geometrical similarity was found between the hexagonal packing conformation of the SA headgroups in the monolayers and the alignment of calcium ions in the (001) plane of HAp. It was suggested that HAp crystals nucleated and grew epitaxially on the monolayer interface.  相似文献   
69.
Optimal design of a Star-LAN includes a few important and difficult sub-problems. An optimal HUB allocation problem is one of the sub-problems. Neural networks based on the Boltzmann machine are suitable for solving such problems. In this paper, we apply the Boltzmann Machine Neural Networks(BMNN) to optimal HUB allocation problems on a Star-LAN computer networks. We also show some numerical experiments to demonstrate performances on solving the problems.  相似文献   
70.
TL-10, Toyoto Robot Language-10, is a BASIC-like robot language. It has functions that define locations and subroutine parameters, which are useful in the accumulation and the transference of robot applied technology. It also has functions to communicate with other computers such as those for vision systems. The important features are described and illustrated by examples.  相似文献   
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