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211.
F. Itoh O. Saitoh M. Kita H. Nagamori H. Oike 《Solar Energy Materials & Solar Cells》1998,50(1-4):119-125
Quaternary chalcopyrite compounds Cu(In1−xAlx)Se2 were prepared by vacuum evaporation method. It is found that the ratio of In/Al determines the nature of semiconducting properties from n-type in the region of In/Al 1 to p-type in the region of In/Al > 1. 相似文献
212.
The aim of this study was to isolate algicidal bacteria so as to control harmful cyanobacterium Microcystis aeruginosa (M.aeruginosa) blooms using biological methods. Nine bacterial strains were isolated to inhibit the growth of M. aeruginosa, among which the MaI11-5 bacterial strain exhibited remarkable algicidal activity against M. aeruginosa cells during the test. Based on the 16S rDNA analysis, the isolated MaI11-5 was identified as Pedobacter sp. through morphology and homology research. The results of cocultivation of the cyanobacteria with MaI11-5 algicidal isolates showed obvious algicidal activity against cyanobacterial cells. The algicidal effect of MaI11-5 exceeded 50% after two days, exceeded 70% after four days, and reached 80% after seven days. The observation results with a scanning electron microscope showed that the cyanobacterial cells aggregated and produced mucous-like substances when cocultivated with the algicidal bacteria. The results indicated that the MaI11-5 bacterial strain may possess a novel function for controlling harmful blooms and further studies will provide new insights into its role in water environment. 相似文献
213.
Shoji Seki Mami Iwasaki Hiroto Makino Yasuhito Yahara Miho Kondo Katsuhiko Kamei Hayato Futakawa Makiko Nogami Kenta Watanabe Nguyen Tran Canh Tung Tatsuro Hirokawa Mamiko Tsuji Yoshiharu Kawaguchi 《International journal of molecular sciences》2022,23(9)
The role of the ligamentum flavum (LF) in the pathogenesis of adolescent idiopathic scoliosis (AIS) is not well understood. Using magnetic resonance imaging (MRI), we investigated the degrees of LF hypertrophy in 18 patients without scoliosis and on the convex and concave sides of the apex of the curvature in 22 patients with AIS. Next, gene expression was compared among neutral vertebral LF and LF on the convex and concave sides of the apex of the curvature in patients with AIS. Histological and microarray analyses of the LF were compared among neutral vertebrae (control) and the LF on the apex of the curvatures. The mean area of LF in the without scoliosis, apical concave, and convex with scoliosis groups was 10.5, 13.5, and 20.3 mm2, respectively. There were significant differences among the three groups (p < 0.05). Histological analysis showed that the ratio of fibers (Collagen/Elastic) was significantly increased on the convex side compared to the concave side (p < 0.05). Microarray analysis showed that ERC2 and MAFB showed significantly increased gene expression on the convex side compared with those of the concave side and the neutral vertebral LF cells. These genes were significantly associated with increased expression of collagen by LF cells (p < 0.05). LF hypertrophy was identified in scoliosis patients, and the convex side was significantly more hypertrophic than that of the concave side. ERC2 and MAFB genes were associated with LF hypertrophy in patients with AIS. These phenomena are likely to be associated with the progression of scoliosis. 相似文献
214.
Large Magnetovolume Effect Induced by Embedding Ferromagnetic Clusters into Antiferromagnetic Matrix of Cobaltite Perovskite 下载免费PDF全文
Ping Miao Xiaohuan Lin Akihiro Koda Sanghyun Lee Yoshihisa Ishikawa Shuki Torii Masao Yonemura Takashi Mochiku Hajime Sagayama Shinichi Itoh Kazutaka Ikeda Toshiya Otomo Yinxia Wang Ryosuke Kadono Takashi Kamiyama 《Advanced materials (Deerfield Beach, Fla.)》2017,29(27)
Materials that show negative thermal expansion (NTE) have significant industrial merit because they can be used to fabricate composites whose dimensions remain invariant upon heating. In some materials, NTE is concomitant with the spontaneous magnetization due to the magnetovolume effect (MVE). Here the authors report a new class of MVE material; namely, a layered perovskite PrBaCo2O5.5+x (0 ≤ x ≤ 0.41), in which strong NTE [β ≈ ?3.6 × 10?5 K?1 (90–110 K) at x = 0.24] is triggered by embedding ferromagnetic (F) clusters into the antiferromagnetic (AF) matrix. The strongest MVE is found near the boundary between F and AF phases in the phase diagram, indicating the essential role of competition between the F‐clusters and the AF‐matrix. Furthermore, the MVE is not limited to the PrBaCo2O5.5+x but is also observed in the NdBaCo2O5.5+x . The present study provides a new approach to obtaining MVE and offers a path to the design of NTE materials. 相似文献
215.
M Kojima S Nakamura Y Kurabayashi H Itoh K Yoshida S Asano T Suchi T Joshita 《Canadian Metallurgical Quarterly》1995,191(11):1072-1077
To clarify the clinicopathological significance of the suppurative lesions without an epithelioid granulomatous response (SLs without Ep) in lymph nodes and their relationship to abscess-forming granulomatous lymphadenitis (AGL) and cat scratch disease (CSD), 10 cases were assessed clinicopathologically and immunohistologically. SLs without Ep were located in the subcapsular sinus, paracortical area and medullary cords, but not in the germinal centers. The microabscesses were surrounded by collections of monocytoid B-lymphocytes (MBLs), histiocytes without epithelioid features, neutrophils, small lymphocytes and small numbers of plasma cells. The majority of the MBLs seen in the SLs without Ep were of the large cell type. The histological triad of toxoplasmic lymphadenitis, i.e., reactive follicular hyperplasia, small clusters of epithelioid cells and aggregates of MBLs, were also seen in all cases. Some of the clinical and pathological findings in our 10 cases were characteristic of CSD, i.e., (1) cat exposure before the lymphadenopathy was in four of the 10 cases, (2) occurrence in autumn and winter months in all cases, (3) typical suppurative granulomas surrounded by palisaded epithelioid cells were in four of the 10 cases, and (4) Warthin-Starry silver stain-positive bacteria were detected in seven of the 10 cases. The results of our study suggest that SLs without Ep are an early stage of CSD. 相似文献
216.
Opportunistic infections are common and major causes of morbidity in patients with AIDS. Endemic mycoses pose serious risks for patients in certain parts of the world. Histoplasmosis occurs in 2-5% of patients with AIDS in the Ohio and Mississippi River valleys of the United States and in over 25% of patients from a few cities. Antigen testing has become a highly useful method for diagnosing histoplasmosis rapidly, evaluating the response to treatment and diagnosing relapse. Treatment with amphotericin B or itraconazole is effective (90% or higher) if the patient is not seriously ill at the time of diagnosis but the mortality approaches 50% for those with multiorgan failure. Itraconazole blood levels should be monitored and drugs that impair the absorption or accelerate the metabolism of itraconazole should be avoided. Prophylaxis with itraconazole may be appropriate in areas with an incidence of histoplasmosis. A recently completed study in cities which have unusually high rates of histoplasmosis will provide greater insight into the role of prophylactic antifungal therapy. 相似文献
217.
N Okayama M Itoh T Joh T Miyamoto T Takeuchi A Moriyama T Kato 《Canadian Metallurgical Quarterly》1998,43(12):2744-2749
We have investigated the effects of dibutyryl cAMP, forskolin, carbamylcholine chloride (carbachol), ionomycin, and 12-O-tetradecanoylphorbol-13-acetate (TPA) on the expression of guinea pig pepsinogen mRNA in monolayer cultured gastric chief cells. After exposure of the cells to each of these compounds for 4 to 24 hr, and at 48 hr after primary culture, total cellular RNA was isolated using acid guanidium-phenol-chloroform and then was reverse transcribed to cDNA. Obtained cDNA was amplified by polymerase chain reaction (PCR) using primers detecting guinea pig pepsinogen mRNA and human beta-actin mRNA as an internal standard. The PCR products were separated and quantified using capillary electrophoresis. Dibutyryl cAMP and forskolin significantly increased pepsinogen mRNA, but carbachol, ionomycin, and TPA failed to increase that. These findings suggested that pepsinogen gene expression was up-regulated by intracellular cAMP, but not by intracellular calcium or protein kinase C in guinea pig chief cells. 相似文献
218.
219.
The key intermediate of a 20(S)-camptothecin 1 synthesis was obtained in a highly enantioselective fashion using an enzyme-catalyzed resolution. A commercially available protease was found to exhibit the highest enantioselectivity with moderate activity, and (S)-ethyl 2-acetoxy-2-[6-(acetoxymethyl)-1,1-(ethylenedioxy)-5-oxo- 1,2,3,5-tetrahydroindolizin-7-yl]butanoate 7c of 98% e.e. was obtained as the remaining substrate. 相似文献
220.
Hideaki Itoh Hisaaki Takao Hiroyasu Iwahara 《Journal of the American Ceramic Society》1993,76(11):2889-2895
Reaction sintering behavior of cBN, which is accompanied by the transformation from hBN to cBN in the presence of 30 wt% diamond seed grains, was investigated under high pressure conditions (6.0–7.5 GPa, 1400–1700°C, 0–30 min) using volatile catalysts such as NH4 NO3 , NH4 Cl, and NH2 NH2 . Fully dense sintered compacts having a Vickers microhardness of more than 5000 kg/mm2 were prepared with no residual catalytic solid components. The activation energy for the conversion from hBN to cBN was 200–230 kJ/mol. Adsorbed N2 , H2 , and/or NH x components which were formed by decomposition of these catalysts during high pressure and temperature treatments, would have a favorable kinetic effect on cBN formation from hBN and its simultaneous sintering. 相似文献