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排序方式: 共有479条查询结果,搜索用时 15 毫秒
81.
Y Sugawara T Konishi M Hiraishi A Sato H Natomi T Aoki M Makuuchi 《Canadian Metallurgical Quarterly》1996,43(10):995-999
A patient with primary gastric carcinoma showing a high level of serum a-fetoprotein (AFP) (368 ng/ml) is described. Subtotal gastrectomy was performed, and a month after surgery the level of serum AFP fell rapidly to within normal limits. Histologically, two types of cells coexisted in the tumor: medullary-type cells resembling trabecular-type hepatocellular carcinoma, and moderately differentiated adenocarcinoma cells. The cells of the former type were arranged mostly in a trabecular pattern with bile granules, but also showed a scirrhous pattern in a restricted area. Immunohistochemistry demonstrated that both types of tumor cells stained positively for AFP. This tumor, which should be classified as a hepatoid adenocarcinoma of the stomach, is of interest because of its rarity, bile secretion (indicating marked differentiation toward a hepatocyte form), and two cellular arrangements-trabecular and scirrhous. 相似文献
82.
MacCallum Robert C.; Browne Michael W.; Sugawara Hazuki M. 《Canadian Metallurgical Quarterly》1996,1(2):130
A framework for hypothesis testing and power analysis in the assessment of fit of covariance structure models is presented. We emphasize the value of confidence intervals for fit indices, and we stress the relationship of confidence intervals to a framework for hypothesis testing. The approach allows for testing null hypotheses of not-good fit, reversing the role of the null hypothesis in conventional tests of model fit, so that a significant result provides strong support for good fit. The approach also allows for direct estimation of power, where effect size is defined in terms of a null and alternative value of the root-mean-square error of approximation fit index proposed by J. H. Steiger and J. M. Lind (1980). It is also feasible to determine minimum sample size required to achieve a given level of power for any test of fit in this framework. Computer programs and examples are provided for power analyses and calculation of minimum sample sizes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
An inherent defect of biliary Cu excretion and subsequent Cu deposition in the liver have been found in Long-Evans Cinnamon (LEC) rats, which are promising models of Wilson disease. LEC and Fischer rats were given water containing Cd (CdCl2) at a level of 5 ppm for 30 days. Regardless of drinking Cd water, LEC rats showed a very high concentration of Cu (200 to 250 microgram/g) and Cu-metallothionein (Cu-MT) (18 mg/g) in the liver. There was no difference of Cd accumulation in the liver between the two strains exposed to Cd (2.6 and 2.7 microgram/g in the Fischer and LEC groups, respectively). However, the renal Cd concentration was slightly but significantly higher in LEC rats (3.5 microgram/g) than in Fischer rats (2.0 microgram/g). The ratio of renal Cd contents to the sum of renal and hepatic Cd contents was significantly higher in LEC rats (0.25) than in Fischer rats (0.15). The serum Cd concentration in Cd-treated LEC rats increased threefold compared to Cd-treated Fischer rats. It seems likely that Cd from the liver is transported into the kidney in the form of Cd, Cu-MT. There was no difference in uptake of Cd in the hepatic MT fraction between the two strains. Although biliary Cu excretion in LEC rats was significantly lower than that in Fischer rats, reduced excretion of Cd into bile was not found in LEC rats. The gross amounts of Cu and Cu-MT influenced the accumulation of Cd in the kidney rather than in the liver when Cd was given orally at a low level to LEC rats. Our results suggest tht Cu and Cd do not share the same sites of hepatobiliary excretion in rats, although the main route of their excretion is via bile. 相似文献
84.
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86.
Sinhachiro Saito KŌzŌ Satoh Tadashi Sugawara 《Journal of Low Temperature Physics》1980,41(1-2):157-167
Anomalous thermal and NMR behavior has been observed in liquid 3He in contact with a single crystal of Cu(NH3)4 · SO4 · H2O, which is a magnetically one-dimensional substance. In the presence of a temperature gradient in the vertical direction and parallel to the crystal surface, the temperature of the system and the 3He NMR signal change abruptly at a temperature just above the antiferromagnetic transition temperature of the salt (0·43 K). From the experimental results it is suggested that at the onset of the anomaly the spin-lattice relaxation time of 3He is reduced and a flow is induced in liquid 3He near the surface of the crystal.This work was supported by a Research Grant of the Iwatani Naoji Foundation and a Grant-in-Aid for Scientific Research (Japan). 相似文献
87.
Y Takahama K Ohishi Y Tokoro T Sugawara Y Yoshimura M Okabe T Kinoshita J Takeda 《Canadian Metallurgical Quarterly》1998,28(7):2159-2166
T lymphocytes express various glycosylphosphatidylinositol (GPI)-anchored surface proteins, such as Thy-1 and Ly-6A. However, functional contribution of GPI-anchored proteins in T cell activation is as yet poorly understood. Here we report the generation of mutant mice deficient in the expression of GPI-anchored molecules exclusively in their T cells. We established mice carrying three identically oriented lox-P sites within the Pig-a gene, which encodes a component essential for the initial step of GPI anchor biosynthesis. These mice were crossed with mice carrying the Cre recombinase gene driven by the T cell-specific p56lck proximal promoter. Offspring carrying both the lox-P-containing Pig-a gene and the Cre transgene exhibited almost complete loss of the surface expression of GPI-anchored molecules on peripheral T cells. Interestingly, those T cells deficient in GPI-anchored molecules were capable of responding to T cell receptor stimulation in vitro and in vivo. These results indicate that T cells lacking the expression of GPI-anchored molecules are functionally competent in exerting TCR-mediated immune responses. 相似文献
88.
Yasushi Kojima Masayuki Shima Tomohiro Motoda Tatsuhiro Jibiki Takashi Sugawara 《Tribology International》2007,40(10-12):1479
The paper describes a method for estimating the coefficient of friction (COF) between sliding surfaces by an indentation of an acute-angled indenter. The COF estimated by the method is compared with the COF measured by a friction tester. The conical indenter, which is made of WC and has an apex angle of 45°, is used for the experiments. A micro-Vickers hardness tester is used for the indentation tests. The friction tester used is one of Bowden–Leben type. A copper and a 0.45% carbon steel are used for the indentation and sliding specimens. The estimation of the COF is based on the equilibrium equation of indentation, which takes the friction between the contacting surfaces of the indenter and the specimen into consideration. The results show that the estimated COF is approximately equal to the measured one. Based on the results, the validity of this method is discussed. 相似文献
89.
The effects of plant and yeast cerebrosides on melanin formation were examined in B16 mouse melanoma cells. Addition of yeast cerebroside significantly reduced melanin content to the same level as that of arbutin in control cells, although there was no suppression by plant cerebrosides and bovine brain cerebroside up-regulated melanin formation. None of the bovine brain cerebrosides examined had any effect on tyrosinase activity, but yeast cerebroside reduced the contents of tyrosinase. The results of the present study clearly showed that melanin formation is regulated by several different cerebrosides via tyrosinase. In addition, the findings presented here suggest that cerebrosides containing a 9-methyl type sphingoid base, such as yeast cerebroside, may be useful as skincare products for suppressing melanin formation. 相似文献
90.
Tomoharu Suzuki Shigeru Oshio Mari Iwata Hisayo Saburi Takashi Odagiri Tadashi Udagawa Isamu Sugawara Masakazu Umezawa Ken Takeda 《Particle and fibre toxicology》2010,7(1):1-8