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21.
G Egusa F Murakami C Ito Y Matsumoto S Kado M Okamura H Mori K Yamane H Hara M Yamakido 《Canadian Metallurgical Quarterly》1993,100(2):249-255
It has recently been reported that there exists a new 'RING-finger' protein family among the zinc-finger (Zf) proteins. Previously, we had isolated the mouse Mel-18 cDNA (mMel-18) encoding the nuclear RING-finger protein that exhibits an ability to bind to a nonspecific DNA column. Here, we have isolated and characterized the human Mel-18 cDNA (hMel-18) using the mMel-18 cDNA as a probe. The deduced hMel-18 protein contains 344 amino acids (38 kDa) with a RING-finger motif, a helix-loop-helix (HLH)-like structure and a Pro/Ser-rich region. The hMel-18 gene is conserved among vertebrates. Its mRNA is highly expressed in placenta, lung and kidney, but the level is low in liver, pancreas and skeletal muscle. Using in situ hybridization, we mapped hMel-18 to band q22 of chromosome 12. It is possible that the Mel-18/bmi-1 gene family represents a mammalian homologue of the Drosophila polycomb gene group. 相似文献
22.
S Murakami T Igarashi T Yuhiki T Tobe K Mikami S Akimoto J Shimazaki O Matsuzaki 《Canadian Metallurgical Quarterly》1994,85(8):1213-1217
In order to evaluate the significance of repeat transurethral resection (TUR) in differentiating stage A1 prostatic adenocarcinoma from those with stage A2, we performed repeat TUR in 34 patients with an initial diagnosis of stage A1 prostatic adenocarcinoma. It was found that residual adenocarcinoma was present in five cases (14.7%), but the diagnosis was changed from stage A1 to stage A2 in only one case (2.9%). In one patient with final diagnosis of stage A1 carcinoma, bone metastases were detected seven months after the repeat TUR. It was concluded that repeat TUR for stage A1 prostatic adenocarcinoma did not yield clinically significant information. 相似文献
23.
Yasuo Koide T. Kawakami Masanori Murakami N. Teraguchi Y. Tomomura A. Suzuki 《Journal of Electronic Materials》1998,27(6):772-775
Schottky barrier heights (SBHs) of a variety of metals (In, Cd, Nb, Ti, W, Cu, Ag, Au, Ni, Pt, and Se) contacting to p-ZnSe
grown by a molecular beam epitaxy method were determined by analyzing capacitance-voltage (C-V) and/or current density-voltage
(J-V) curves. The SBH values of the Au and Ni contacts were determined from intersections of straight lines of the C−2-V curves to be 1.23 and 1.13 eV, respectively. The J-V calculations provided a large SBH value of 1.2 ± 0.1 eV for a variety
of metals, indicating that the Fermi-level could be pinned at the contact interface. Reduction of the SBH values to a level
lower than 0.4 eV and/or increase of doping concentrations to a level higher than 1020 cm−3 are essential to obtain an ohmic contact with contact resistivity of around 10−3 Ω·cm2. 相似文献
24.
25.
Yukihisa Tanaka Jiro Hirano Tadashi Funada 《Journal of the American Oil Chemists' Society》1992,69(12):1210-1214
In an attempt to concentrate the content of DHA (docosahexaenoic acid) in a glyceride mixture containing triglyceride, diglyceride
and monoglyceride, fish oil was hydrolyzed with six kinds of microbial lipase. After the hydrolysis, free fatty acid was removed
and fatty acid components of the glyceride mixtures were analyzed. When the hydrolysis withCandida cylindracea lipase was 70% complete, the DHA content in the glyceride mixture was three times more than that in the original fish oil.
The EPA (eicosapentaenoic acid) content became almost 70% of the original fish oil. Hydrolysis with other lipases did not
result in an increase in the DHA content in the glyceride mixtures. Hydrolysis of DHA-rich tuna oil (DHA content is about
25%) withCandida cylindracea lipase resulted in 53% DHA in the glyceride mixture. The EPA content, however, remained close to that of the original tuna
oil. In this report, the acyl chain specificity of lipases is evaluated in terms of hydrolysis resistant value (HRV). HRV
is the ratio between the DHA contents in the glyceride mixture of hydrolyzed oil and original oil. HRV clearly indicates differences
in hydrolysis between DHA and other fatty acids (e.g., saturated and monoenoic acids). 相似文献
26.
The Bi2O31bM2O5 films (M=V, Nb and Ta) were prepared by a rapid quenching technique using a twin-roller type equipment. Quenched film of pure Bi2O3 partially precipitated a tetragonal phase which differs from well-known β-Bi2O3 in structure. In every (Bi2O3)0.975 (M2O5)0.025 composition (2.5% M2O5), the tetragonal phase was obtained as single phase, and the tetragonality became greater than that of the pure Bi2O3. Beyond this composition, the tetragonality decreased to form δ-phase with a fcc structure with increasing the M2O5 content. The lowest V2O5 content forming a δ-phase was 5%, while a slight tetragonality still remained in the samples containing 10% Nb2O5 and 10% Ta2O5, respectively. From the measurement of the photoconductivities of the quenched films, it was proved that a photoconduction appeared in the tetragonal phase while no photoconductivity was observed in the cubic phase. The characteristic of the photoconduction was that a remarkable decrease in the resistivity was observed when a light of ca. 500 nm in wave length was irradiated on the films. 相似文献
27.
Mitsuhiro Fukuta Tadashi Yanagisawa Hiroaki Iwata Kazutaka Tada 《International Journal of Refrigeration》2002,25(7)
This paper discusses the feasibility of a vapor compression/absorption hybrid refrigeration cycle for energy saving and utilization of waste heat. The cycle employs propane as a natural refrigerant and a refrigeration oil as an absorbent. A prototype of the cycle is constructed, in which a compressor and an absorption unit are combined in series. The performance of the cycle is examined both theoretically and experimentally. Although the solubility of the propane with the oil is not enough as a working pair in the absorption unit, the theoretical calculation shows that the hybrid cycle has a potential to achieve a higher performance in comparison with a simple vapor compression cycle by using the waste heat. In the experiment, the prototype cycle is operated successfully and it is found that an improvement of an absorber is necessary to achieve the good performance close to the theoretical one. The application of an AHE (absorber heat exchanger) can reduce the heat input to a generator. Further examinations on some other combinations of refrigerant/refrigeration oil and additives are desirable. 相似文献
28.
By employing a single thick molybdenum fibre-copper matrix composite with very weak interfacial bonding, it was confirmed that flow stress, internal stress, effective stress and change in flow stress due to change in strain rate of the composite obey the simple rule of mixtures; strain-hardening exponent, stress exponent of strain rate, effective stress exponent of dislocation velocity and activation volume obey the modified rule of mixtures in the whole range of plastic deformation of the composite. This means that the inherent features of the fibre in the present composite were conserved beyond the failure strain of the fibre tested alone, and the above deformation parameters of the composite were, to a first approximation, determined by the inherent parameters of the fibre and the matrix. 相似文献
29.
Since the natural estrogens 17 beta-estradiol (E2) and estron (E1), and the synthetic estrogen 17 alpha-ethynyl estradiol (EE2) have strong endocrine disrupting effects and the tendency to persist in effluent from wastewater treatment plants, effective measures are needed to remove them from wastewater. In this research, to gain an understanding of the characteristics of estrogen decomposition by ozonation, experiments were conducted using effluent from an actual wastewater treatment plant. In this experiment, estrogen was added to effluent at a concentration of 200 ng/l and 20 ng/l before the ozonation experiments. The results showed 90% or more of estrogen concentration and estrogenic activity of E2, El and EE2 to be removed at an ozone dose of 1 mg/l. At an ozone dose of 3 mg/l, the estrogen concentration and estrogenic activity of E2, El and EE2 in the treated water fell below the detection limit. The removal rate was not influenced by the kind of estrogen. No generation of byproducts with estrogenic activity was observed. The authors conclude that estrogen in secondary treated wastewater can be almost entirely removed at the practical ozone dose rate applied for the purpose of disinfection, which is up to about 5 mg/l. 相似文献
30.
T Ganbo K Hisamatsu H Inoue A Mizukoshi R Goto Y Murakami 《Canadian Metallurgical Quarterly》1995,33(4):199-202
The effects of leukotrienes C4 and D4 on ciliary activity of human paranasal sinus mucosa were investigated in vitro. Normal mucosa was surgically obtained from human paranasal sinuses and incubated in the form of tissue culture. Ciliated cells were magnified under an inverted microscope, and ciliary activity was photoelectrically measured. LTD4 progressively inhibited ciliary activity, and showed a more potent effect on ciliary activity compared to LTC4. The concentrations of LTC4 and LTD4 in the incubation medium were determined by radioimmunoassay when the mucosa was incubated with 10(-8) M LTC4. The concentration of LTD4 gradually increased and after 90 min reached the maximum of 0.71 x 10(-8) M, while that of LTC4 was reduced to about 10% of its initial concentration within 60 min. These results suggested the possible conversion of LTC4 to LTD4 on the mucosa, and that LTC4 can inhibit ciliary activity by means of LTD4. 相似文献