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41.
42.
Taguchi T Rao Z Ito M Matsuda M 《Journal of materials science. Materials in medicine》2011,22(10):2357-2363
We developed a poly(ethylene glycol) (PEG) derivative with oleyl groups, so-called “cell adhesive”, for the promotion of human
hepatocellular carcinoma HepG2 cell spheroids. Our approach was based on crosslinking of the cell membrane with a cell adhesive
via a hydrophobic interaction. A cell adhesive, PEG derivative with hydrophobic oleyl groups at both ends was synthesized
and characterized. HepG2 spheroids formed when the adhesive was added to cell suspensions. The size of the spheroids increased
with time in culture. In addition, Ammonia elimination of HepG2 spheroid with cell adhesive was 3.4 times higher than that
without cell adhesive. Furthermore, albumin secretion from HeG2 spheroids grown with the cell adhesive for 7 days was 3.3
times that from HepG2 spheroids grown without cell adhesive. Fluorescence microscopy showed greater albumin staining in spheroids
grown with cell adhesive compared with spheroids grown without adhesive. This cell adhesive may be useful not only for single
type of cells but also for multi types of cells to form artificial organs. This cell adhesive will be a key material for liver
tissue engineering when it will apply to primary hepatocytes. 相似文献
43.
A single wavelength light source in 1.5-μm range was developed using InGaAsP/InPlambda/4 -shifted distributed feedback (DFB) semiconductor heterostructures. Superiority of thelambda/4 -shifted DFB structure in terms of stability of the main mode at the Bragg wavelength was shown theoretically, in which the threshold, the output, and the polarization characteristics were taken into account. Alambda/4 -shifted corrugated grating was made by a newly developed negative and positive photoresists technique. Buried heterostructure (BH) diode lasers with nonreflective window ends were fabricated and highly stable single-mode operation with a low threshold was obtained reproducibly. Direct modulation properties and life-tests results indicated that thelambda/4 -shifted DFB lasers could be a reliable single-mode light source in a long span lightwave transmission system in 1.5-μm range. 相似文献
44.
S Kobayashi T Yamamoto C Akiba N Katayama K Sakai A Maruta K Ogawa S Fujisawa R Sakai J Taguchi 《Canadian Metallurgical Quarterly》1994,35(7):713-716
Auer-rod-like bodies were found in plasma cells from a 74-year-old man with plasma cell dyscrasia. These bodies exhibited red purple staining by May-Giemsa staining and were indistinguishable from Auer bodies often found in acute myeloid leukemia. These bodies, however, failed to stain with peroxidase and showed acid phosphatase positivity. Bone marrow examinations were performed three times at the sternum or iliac crest. The proportions of plasma cells were 4.4%, 3.4% and 3.8%. The Auer-rod-like bodies were found in 0.05% (2/3824), 0.07% (4/6883) and 0.08% (2/2656) of the plasma cells. 相似文献
45.
When tensile stress was applied to epoxy resin filled with silica particles, we expected that the stress concentration would occur in the epoxy matrix near the interface between the matrix and the silica particles. We investigated the plastic deformation of the network chains near the interface, which was quantitatively evaluated using a polarized microscope FTIR technique. A biphenol‐type epoxy resin, which has a mesogenic group in the backbone moiety, was used as the matrix resin. As a result, reorientation of the network chains along the direction of the tensile stress near the interface with the silica particles was observed. Especially when the silica/matrix interface has good bonding properties, the reorientation of the network chains was observed at a larger area around the silica particles. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 787–794, 2003 相似文献
46.
47.
The hypocholesterolemic efficacies of various polyunsaturated fatty acids were compared in rats given cholesterol-enriched
diets.Oenothera biennis Linn oil (OBLO, linoleic +γ-linolenic), sunflower oil (linoleic), palm oil (PLO, oleic+linoleic), soybean oil (linoleic+α-linolenic),
high-oleic safflower oil (oleic+linoleic), or mixed oil (linoleic+α-linolenic) was added to the diet at 200 g/kg (20% groups).
OBLO was also added at 100 g/kg diet (10% group). The serum total and very low density lipoprotein+intermediate lipoprotein+low
density lipoprotein cholesterol concentrations of the 10 and 20% OBLO groups were consistently lower than those in the other
groups. The liver cholesterol concentration in the PLO group was lower in all groups. The liver cholesterol concentrations
in the 10 and 20% OBLO groups were also lower than in the other groups. There were no significant differences in the fecal
neutral sterol and bile acid extraction among groups. 相似文献
48.
Room temperature CW operation of distributed-feedback buried-heterostructure InGaAsP/InP lasers emitting at 1.57 ?m was achieved. A DC threshold of about 250 mA at 25°C and a temperature coefficient of the lasing wavelength of 1.0 ?/°C were obtained. Some of these lasers manifested single longitudinal mode operation both in DC condition and in deeply modulated condition at 500 Mbit/s. 相似文献
49.
Yuasa T. Akiba M. Takeda T. Kazama M. Hoshino A. Watanabe Y. Hyodo K. Dilmanian F.A. Akatsuka T. Itai Y. 《IEEE transactions on nuclear science》1997,44(5):1760-1769
We describe a new system of incoherent scatter computed tomography (ISCT) using monochromatic synchrotron X rays, and we discuss its potential to be used in in vivo imaging for medical use. The system operates on the basis of computed tomography (CT) of the first generation. The reconstruction method for ISCT uses the least squares method with singular value decomposition. The research was carried out at the BLNE-5A bending magnet beam line of the Tristan Accumulation Ring in KEK, Japan. An acrylic cylindrical phantom of 20-mm diameter containing a cross-shaped channel was imaged. The channel was filled with a diluted iodine solution with a concentration of 200 μgI/ml. Spectra obtained with the system's high purity germanium (HPGe) detector separated the incoherent X-ray line from the other notable peaks, i.e., the iKα and Kβ1 X-ray fluorescent lines and the coherent scattering peak. CT images were reconstructed from projections generated by integrating the counts In the energy window centering around the incoherent scattering peak and whose width was approximately 2 keV. The reconstruction routine employed an X-ray attenuation correction algorithm. The resulting image showed more homogeneity than one without the attenuation correction 相似文献
50.