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71.
Hayashi M Maeda Y Hashimoto Y Murooka Y 《Journal of Bioscience and Bioengineering》2000,89(6):550-553
The transformation of Mesorhizobium huakuii subsp. rengei B3 with either pBBR122 or pKT230 was carried out. We determined the optimal conditions required for transformation by electroporation and obtained up to 10(5) CFU/microg pBBR122. Plasmids prepared from strain B3 yielded higher transformation efficiency than those from various dam or dcm mutant strains of Escherichia coli. This result suggests that a high transformation efficiency is not related to the methylation of plasmid DNA in E. coli. Using the optimal conditions for electroporation, we performed transformation of several species of Rhizobium, Mesorhizobium and Sinorhizobium. All tested strains of these species were transformed with pBBR122. Strains of M. huakuii and R. phaseoli AHU1133 were transformed at high efficiency, whereas transformation efficiencies of Rhizobium sp. NGR234 and S. meliloti strains were less than 2 x 10(3) CFU/microg plasmid DNA. 相似文献
72.
Adaptive control of surviving symbol replica candidates in QRM-MLD for OFDM MIMO multiplexing 总被引:2,自引:0,他引:2
Kawai H. Higuchi K. Maeda N. Sawahashi M. 《Selected Areas in Communications, IEEE Journal on》2006,24(6):1130-1140
This paper proposes adaptive control of the number of surviving symbol replica candidates, S/sub m/ (m denotes the stage index), based on the minimum accumulated branch metric of each stage in maximum-likelihood detection employing QR decomposition and the M-algorithm (QRM-MLD) in orthogonal frequency-division multiplexing with multiple-input-multiple-output (MIMO) multiplexing. In the proposed algorithm, S/sub m/ at the mth stage (1/spl les/m/spl les/N/sub t/, N/sub t/ is the number of transmission antenna branches) is independently controlled using the threshold value calculated from the minimum accumulated branch metric at that stage and the estimated noise power. We compared the computational complexity of QRM-MLD employing the proposed algorithm with that of conventional methods at the same average packet error rate assuming the information bit rate of 1.048 Gb/s in a 100-MHz channel bandwidth (i.e., frequency efficiency of approximately 10 bit/s/Hz) using 16QAM modulation and turbo coding with the coding rate of 8/9 in 4-by-4 MIMO multiplexing. Computer simulation results show that the average computational complexity of the branch metrics, i.e., squared Euclidian distances, of the proposed adaptive independent S/sub m/ control method is decreased to approximately 38% that of the conventional adaptive common S/sub m/ control and to approximately 30% that of the fixed S/sub m/ method (S/sub m/=M=16), assuming fair conditions such that the maximum number of surviving symbol replicas at each stage is set to M/spl circ/=16. 相似文献
73.
In order to study the role of IL-4 and IL-5 in allergen-induced airway hyperresponsiveness in mice, the effect of the combined administration of anti-IL-4 and anti-IL-5 monoclonal antibodies (mAbs) on IgE response, airway inflammation and airway hyperresponsiveness was studied in sensitized Balb/c mice. Three inhalations of antigen caused an increase in the number of eosinophils in bronchoalveolar lavage fluid and in airway responsiveness to acetylcholine, with a significant elevation in the serum antigen-specific IgE level. Anti-IL-4 mAb inhibited IgE production but did not affect airway eosinophilia or hyperresponsiveness. Moreover, anti-IL-5 mAb inhibited airway eosinophilia but did not affect IgE production or airway hyperresponsiveness. The combined administration of anti-IL4 and anti-IL-5 mAbs, however, inhibited IgE antibody production, airway eosinophilia and hyperresponsiveness. These results suggest that inhibitory action of IL-4 and IL-5 in combination can effectively suppress the onset of antigen-induced airway hyperresponsiveness in mice. 相似文献
74.
K Ueda M Konishi K Maeda K Hamada M Sakamoto E Yoshimoto T Majima K Mikasa E Kita R Sano T Masutani N Narita 《Canadian Metallurgical Quarterly》1998,72(12):1325-1329
A 78-year-old female was admitted with complaints of malaise and fatigue in the legs. The patient was diagnosed as severe aplastic anemia and treatment was started with metenolone and steroid pulse therapy. Administration of antibiotics and granulocyte-colony stimulating factor which led to a resolution of the high fever. About four months after admission, the patient developed vomiting and abdominal pain with a spiking fever. The next day after suddenly losing consciousness, she died. B. cereus was isolated from blood cultures. Autopsy specimens of the liver, cardiac muscle and lung showed changes due to B. cereus. This pathogen is widely distributed in nature. We should not overlook B. cereus as a contamination, but rather should consider it a potential pathogen in immunocompromised hosts, when it is isolated from blood cultures. 相似文献
75.
Primary biliary cirrhosis associated with cholangiocarcinoma 总被引:1,自引:0,他引:1
76.
A Taketomi R Tamada K Takenaka R Kawano T Maeda K Sugimachi 《Canadian Metallurgical Quarterly》1998,5(4):833-835
Biliary cystadenoma is a rare cause of obstructive jaundice. We report a case of a 78-year-old Japanese man with biliary cystadenoma presenting repetitive abdominal pain and jaundice. Ultrasound sonography revealed a hyperechoic mass in the left lateral lobe of the liver. Histological examination revealed a biliary cystadenoma. Intracystic hemorrhage was assumed to be the cause of obstruction of the bile ducts. 相似文献
77.
The fine specificity of the cellular immune response to Candida albicans (i.e., recognition of different antigenic components) between normal controls and human immunodeficiency virus-infected patients in various stages of disease was compared. C. albicans-specific T cells, enriched by antigen stimulation and interleukin-2 expansion, were challenged with antigenic fractions of different molecular weight obtained by SDS-gel fractionation of C. albicans extracts in the presence of autologous mononuclear cells as antigen-presenting cells. Proliferative responses showed similar patterns of reactivity between controls and category A and B seropositive subjects. Category C patients with concurrent C. albicans infections did not give rise to C. albicans-specific T cell lines, confirming the T cell defect. Patients without clinically evident C. albicans infection had a low but broad reactivity pattern of C. albicans-specific T cells. These results suggest that depletion of C. albicans-specific T cells, independent of their fine specificity, occurs along with disease progression. 相似文献
78.
This letter discusses the problem of designing a feedback compensator that attains the infinite gain margin under the uncertainties of feedback gains. A sufficient condition is given for the existence of compensators and then it is shown that the condition becomes necessary subject to the requirement that the feedback system is decoupled. The nonlinear case is also discussed. 相似文献
79.
Antitumor activity of degraded products of lentinan: its correlation with molecular weight 总被引:1,自引:0,他引:1
Twelve of 25 patients with mixed connective tissue disease complained of xerostomia and/or ocular symptoms of keratoconjunctivitis sicca. In addition to the clinical features of mixed connective tissue disease, all 12 patients had high titers of antibody to the ribonuclease-sensitive component of the extractable nuclear antigen. Eight patients had both clinical xerostomia and keratoconjunctivitis sicca, one had keratoconjunctivitis sicca and salivary gland enlargement, while there had xerostomia but no ocular complaints. Sj?rgren's syndrome was confirmed in all 12 patients by means of Schirmer's tests, Rose Bengal staining tests, salivary gland scintiscans, radionuclide excretion studies in saliva, parotid sialographies, and lip biopsies. At least three of these tests were abnormal in all patients. 相似文献
80.
Fumitaka Horii Ryozo Kitamaru Shiro Maeda A. Saika Takehiko Terao 《Polymer Bulletin》1985,13(2):179-184
Summary High-resolution solid-state 13C NMR spectra and 13C relaxation times T1 and T1 have been measured at 40–100° C for uniaxially oriented polyethylene films with the drawing direction parallel to the magnetic field; this sample has a unique morphological structure that the noncrystalline chains are nearly disordered irrespective of the high degree of drawing. A sharp resonance line(line A) appears at the position corresponding to the principal value 33 of the chemical shift tensor for the CH2 carbons with the trans-trans conformation. Another sharp linedine B) is observed at almost the same chemical shift as for the CH2 carbons of polyethylene in solution. Although these observations are similar to those for a cold-drawn polyethylene sample reported previously, line B is much enhanced in intensity and the linewidth is narrower in the present sample, reflecting the disorientation of the noncrystalline component. It is found from T1 measurements that line A contains two components with different molecular mobility, both being assigned to the crystalline components. On the other hand, the line B is composed of a single component assignable to the noncrystalline component with liquid-like molecular mobility. 相似文献