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21.
M Fujimoto H Kanzaki H Nakayama T Higuchi H Hatayama M Iwai Y Kaneko T Mori J Fujita 《Canadian Metallurgical Quarterly》1996,137(3):1096-1101
Differentiation of endometrial stromal cells (decidualization) is essential for embryo implantation and maintenance of pregnancy. By sequential complementary DNA subtractive hybridization, one of the messenger RNAs (mRNA) induced by progesterone in human endometrial stromal cells decidualized in vitro was identified as that of a tissue transglutaminase type II (TGase). TGase mRNA was induced within 6 h after the addition of progesterone to the culture, and the effect was dose dependent. Both the TGase inhibitor monodansylcadaverine and oligodeoxynucleotide complementary to the TGase mRNA inhibited the decidualization, as assessed by PRL production and morphological transformation. Expression of TGase mRNA in human decidua and endometria exposed to high levels of progesterone in vivo was demonstrated by Northern blotting and in situ hybridization. These data suggest that TGase is necessary for the decidualization of human endometrial stromal cells and that clarification of the mechanism of action of TGase will facilitate further insight into the diagnosis and treatment of infertility. 相似文献
22.
Y Segawa N Takigawa K Mandai Y Maeda I Takata N Fujimoto K Jinno 《Canadian Metallurgical Quarterly》1997,16(2-3):229-238
Serum p53 protein levels were measured in 36 patients with small cell lung cancer (SCLC) and 35 patients with benign lung diseases in order to evaluate the relationship of these levels to clinicopathological features of SCLC. Serum levels of p53 protein were measured by an enzyme-linked immunosorbent assay, p53 protein level was 23.92 +/- 6.78 pg/ml in patients with SCLC, and similar to that (17.47 +/- 2.86 pg/ml) in patients with benign lung diseases. By the clinical stage of SCLC, the mean level of p53 protein was 16.68 +/- 4.62 pg/ml in 21 patients with limited disease, and lower than that in 15 patients with extensive disease (34.05 +/- 14.84 pg/ml) (P = 0.23). The levels of p53 protein were not correlated with age, smoking index, or presence of cancer history for patients with SCLC. However, immunohistochemical examination disclosed a mild correlation between the expression of p53 protein by SCLC tumor and p53 protein serum level (r = 0.45, P = 0.02). Two patients with SCLC had an elevated serum level of p53 protein (> 2 S.D. above the mean for benign lung diseases). However, measurement of p53 protein serum level was not found to be clinically useful for detection of SCLC. 相似文献
23.
24.
The setup and deposition conditions of electrode arrangement and pressure have been studied to synthesize diamond films at high growth rate on wide area efficiently by arc discharge plasma jet chemical vapor deposition. An apparatus has been used in which four plasma torches, one is used for cathode and the others for divided anodes, are arranged and the positions of these torches are changeable. Growth rate, deposition area and thickness of diamond films have increased with changing the electrode arrangements without improvement of thickness variation. Maximum growth rate of our apparatus has occurred at the pressure of 6.7 kPa and diamond films that have less variations of quality and surface roughness have been synthesized at lower pressure during deposition. Moreover, a high conversion rate, which is the ratio of carbon atoms that form diamond in supplied methane gas, of 16% has been obtained at the pressure of 6.7 kPa and methane concentration of 2%. 相似文献
25.
Nobuo Ishizawa Atsushi Saiki Takeshi Yagi Nobuyasu Mizutani Masanori Kato 《Journal of the American Ceramic Society》1986,69(2):18-C-
Crystals of yttria partially stabilized zirconia were grown by the arc-image floating-zone technique and studied by transmission electron microscopy. Crystals annealed at 1700°C consist of tetragonal precipitates and a cubic matrix. The platelike domains in a precipitate are twin-related tetragonal variants stacked alternately parallel to the (011) twin plane. The axial relations between the tetragonal precipitate and the cubic matrix are [100]tetragonal |[100]cubic , [011]tetragonal |[011]cubic . 相似文献
26.
Tensile tests of a 17Cr-7Ni-1Al steel were carried out at 0.1, 300 and 600 MPa hydrostatic pressure, and the mechanical properties of the material were found to be considerably changed by the pressure. The martensitic transition temperatureM
s
decreased under pressure. The volume fraction of-martensite induced by tensile deformation increased with strain, but was suppressed by hydrostatic pressure. The yield stress increased with pressure. The yield surface became a nonlinear cone with a pointed apex. The stress-strain curve was considerably changed by pressure, and was expressed by a modified identical-strain model (law of mixture) as a quantitative function. Uniform-strain limit increased with pressure. It was found that these changes were not caused by the mechanical effect of hydrostatic pressure, but by its thermodynamic effects. 相似文献
27.
Electrical conductivity of two types of lanthanum-doped barium titanote ceramics with different dopant levels was measured at temperatures between 900 and 1250° C andP
O
2from 10–5 to 1 atm. The activation energies of the conduction for the two are interpreted in terms of the formation energy of ionized oxygen vacancies even in such a highP
O
2region. This fact is in contrast with a well -known controlled -valency model proposed for rare- earth -doped semi-conducting perovskites. In a lightly lanthanum-doped specimen, semiconduction achieved at elevated temperatures is retained on cooling the specimen to room temperature, whereas in a heavily doped specimen, the resultant high-temperature semiconduction changed to insulation on cooling. The former behaviour on cooling is successfully explained by a metastabilization of oxygen vacancies accompanied by electrons formed at elevated temperatures. 相似文献
28.
Catalytic dehydrogenative coupling of methane on active carbon. Effect of metal supported on active carbon 总被引:3,自引:0,他引:3
Ethane, ethene, ethyne and hydrogen are obtained in good yields via dehydrogenative coupling of methane in the presence of active carbon as a catalyst. The product yield is increased by supporting metal on active carbon. 相似文献
29.
Toshihide Suzuki Teruo Miyazawa Kenshiro Fujimoto Miki Otsuka Masako Tsutsumi 《Lipids》1993,28(8):775-778
The levels of phosphatidylcholine hydroperoxide in serially cultured human fetal diploid fibroblasts at various population
doubling levels were determined by high-performance liquid chromatography combined with chemiluminescence detections. This
methodology utilizes a mixture of cytochromec and luminol as post-column hydroperoxide group specific luminescent reagents. The cellular hydroperoxide content increased
with age from 0.34 to 27.72 pmol/106 cells. At the end of the cells'in vitro lifespan (51st population doubling level), the hydroperoxide content per 106 cells reached about 80 times the level found in cells of the 20th population doubling level. Supplementation of exogenous
α-tocopherol to the culture medium prevented hydroperoxide accumulation, but did not extent the lifespanin vitro. The results indicate that substantial intracellular phospholipid hydroperoxide accumulation occurred in the course of aging
of human fetal liploid fibroblasts. 相似文献
30.
Koki Murano Tomoyoshi Shimobaba Atsushi Sugiyama Naoki Takada Takashi Kakue Minoru Oikawa Tomoyoshi Ito 《Computer Physics Communications》2014
We report fast computation of computer-generated holograms (CGHs) using Xeon Phi coprocessors, which have massively x86-based processors on one chip, recently released by Intel. CGHs can generate arbitrary light wavefronts, and therefore, are promising technology for many applications: for example, three-dimensional displays, diffractive optical elements, and the generation of arbitrary beams. CGHs incur enormous computational cost. In this paper, we describe the implementations of several CGH generating algorithms on the Xeon Phi, and the comparisons in terms of the performance and the ease of programming between the Xeon Phi, a CPU and graphics processing unit (GPU). 相似文献