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121.
122.
A simple and practical method for minimizing non-linear image contrast in spherical aberration-corrected (C(S)-corrected) high-resolution transmission electron microscopy is presented. The effectiveness of the method is considered from the viewpoints of theoretical formulations and image simulations including second-order imaging effects. The method is one of the advantages of C(S)-correction and applied to high-resolution images down to 0.1 nm. The dynamical diffraction effect is carefully evaluated, which shows that the phase deviation of diffracted waves from pi/2 violates the present method in thicker crystals over approximately 10 nm. 相似文献
123.
The JSNS, a spallation neutron source of J-PARC (JAERI-KEK Joint Project of the High Intensity Proton Accelerator) has 23 neutron beam lines. In the present study, a database was formulated for an optimum shielding design using the MCNP-X code. The calculations involved two steps. In the first step, the neutron distributions were created in the typical neutron beam line with a model that included the spallation neutron source target. The neutron currents evaluated flowed from the duct into the duct wall which was the boundary source for the bulk shield surrounding the beam line. In the second step, bulk-shield calculations were performed for the various shielding materials (iron, concrete, heavy concrete and so on) used and their composites up to thicknesses of 3 m. The results were compared with each other. Composite material shields of iron and such hydrogeneous materials as polyethylene or concrete were more effective. A typical design was prepared for a beam line within 25 m distance from a moderator, as a sample. 相似文献
124.
125.
Y Watanabe K Kawai S Ohashi C Yokota S Suzuki K Yamashita 《Canadian Metallurgical Quarterly》1994,140(1):45-52
There are three classes of Fc gamma receptor proteins, Fc gamma RI (CD64), Fc gamma RII (CDw32), and Fc gamma RIII (CD16), which are encoded by at least eight genes. In this review we summarize some of the biological advances in the Fc gamma receptors during the past year, specifically: 1) identification of genes and their products; 2) regulation of gene expression and modulation of receptor number; 3) cellular functions and mechanisms of signal transduction; 4) ligand binding and the role of polymorphisms; and 5) soluble Fc gamma receptors. We also highlight the direct clinical applications of this Fc gamma receptor research. 相似文献
126.
BL Slomiany J Liu T Kawai A Czajkowski A Slomiany 《Canadian Metallurgical Quarterly》1993,88(6):881-886
There is much interest in the range of genetic aberrations which occur in human malignancies. An immunohistochemical study has been carried out to investigate the consistency of expression of abnormally accumulated p53 protein in paired samples of archival primary and metastatic carcinomas. The staining of methacarn-fixed tissue from 136 matched pairs of mammary carcinoma and 20 cancers from other sites was completed using antibody CM-1 and DO1 in a sensitive peroxidase-conjugated streptavidin-biotin technique. The majority of tumour cells were positive in 25% and the tumours were negative in 17% of the primary carcinomas; staining was heterogeneous in the remaining cases. Staining was identical in 180/186 (96%) metastatic lesions. An ELISA assay carried out on 12 matched pairs of the tumour specimens demonstrated that altered conformation of the aberrant p53 protein present in a primary lesion was maintained in its metastasis. These data indicate that alterations in the p53 gene result in a relatively stable phenotype and that progression of disease is not usually accompanied by either further mutation or loss of the mutant allele. 相似文献
127.
128.
S Kawai T Fujimoto Z Zha K Asami T Oka Y Kaneko Y Takaue T Ninomiya K Nishikawa T Tsuchiya 《Canadian Metallurgical Quarterly》1993,34(2):128-136
One hundred and eighty eight children with acute lymphoblastic leukemia (ALL) were treated in a Children's Cancer and Leukemia Study Group high-risk ALL 874 study from April, 1987 to September, 1991. These patients received a four-drug induction regimen followed by the early consolidation regimen, cranial irradiation at 6 months of remission and three years of continuation therapy with rotational administration of four drugs. The patients were randomized into two regimens. In regimen A, the consolidation chemotherapy consisted of the intermediate dose cytosine arabinoside (Ara-C), cyclophosphamide (CPM) plus 6MP, and in regimen B, it consisted of high-dose Ara-C plus CPM. Regimen A was given to 106 patients and 82 patients received regimen B. The complete remission induction rate for regimen A and B was 89.4% (93/104) and 98.7% (78/79), respectively. The 3-year event-free-survival (EFS) rate was 70.6% for regimen A, which was higher than the 56.7% for regimen B. The 3-year EFS rate was 44.4% for the 53 patients with an initial leukocyte count > or = 10 x 10(4)/microliters and 72.2% for 132 patients with a leukocyte count < 10 x 10(4)/microliter. We considered that Ara-C plus L-asp, added to the conventional high-risk ALL 811 protocol, improved the prognosis of the high risk ALL patients. However, further intensive chemotherapy was required for improvement of the outcome of the patients with hyperleukocytosis (> or = 10 x 10(4)/microliters). 相似文献
129.
The letter reports the concept of a new switching/amplifying network, and its basic performance, for scanning the down-link beam rapidly in multibeam satellite systems. Experiments in the K-band have shown 85% power-combining efficiency, more than 17 dB isolation and 400 ns switching speed. 相似文献
130.
Paveena Srirangsan Kiyoshi Kawai Naoko Hamada-Sato Manabu Watanabe Toru Suzuki 《Food chemistry》2010,119(1):209-213
In order to improve the remaining activity of a practically important freeze-dried enzyme, xanthine oxidase (XOD), the effects of disaccharide (sucrose and trehalose), polymer (bovine serum albumin: BSA and dextran) and a mixture of them on the loss of XOD activity during freeze-drying and subsequent storage were investigated. All samples were amorphous solids and their glass transition temperatures (Tg) were evaluated by using differential scanning calorimetry. Although dextran showed no stabilizing effect on the freeze-dried XOD, the others protected XOD from the activity loss during freeze-drying to a certain extent. It was found that the mixture of disaccharide (sucrose or trehalose) and BSA improved the XOD activity synergistically. The XOD activity of the samples decreased gradually during storage at a temperature range of between 25 and 60 °C. Samples stored at temperatures below the Tg showed a lower loss of XOD activity than those stored at just the Tg. 相似文献