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排序方式: 共有393条查询结果,搜索用时 25 毫秒
81.
Hiromi Kubagawa Christopher M. Skopnik Khlowd Al-Qaisi Rosaleen A. Calvert Kazuhito Honjo Yoshiki Kubagawa Ruth Teuber Pedram Mahmoudi Aliabadi Philipp Enghard Andreas Radbruch Brian J. Sutton 《International journal of molecular sciences》2021,22(13)
Both non-immune “natural” and antigen-induced “immune” IgM are important for protection against pathogens and for regulation of immune responses to self-antigens. Since the bona fide IgM Fc receptor (FcµR) was identified in humans by a functional cloning strategy in 2009, the roles of FcµR in these IgM effector functions have begun to be explored. In this short essay, we describe the differences between human and mouse FcµRs in terms of their identification processes, cellular distributions and ligand binding activities with emphasis on our recent findings from the mutational analysis of human FcµR. We have identified at least three sites of human FcµR, i.e., Asn66 in the CDR2, Lys79 to Arg83 in the DE loop and Asn109 in the CDR3, responsible for its constitutive IgM-ligand binding. Results of computational structural modeling analysis are consistent with these mutational data and a model of the ligand binding, Ig-like domain of human FcµR is proposed. Serendipitously, substitution of Glu41 and Met42 in the CDR1 of human FcµR with mouse equivalents Gln and Leu, either single or more prominently in combination, enhances both the receptor expression and IgM binding. These findings would help in the future development of preventive and therapeutic interventions targeting FcµR. 相似文献
82.
This paper proposes an engineering ethics education method for students on the basis of continuous education to improve communication ability. First, through the process of debate, the students acquire the fundamental skills necessary to marshal their arguments, to construct rebuttals, and to summarize debates. Second, the students study the fundamental techniques to make a presentation on technical subjects related to electrical engineering. Following these classes, in lectures on engineering ethics, the students probe the causes of various accidents and consider better approaches for avoiding such accidents with each other. In most cases, the students can express good and commonsensical opinions from an ethical standpoint. However, they can hardly make judgments when the situations, such as the human relations in the above accidents, are set up in concrete terms. During the engineering ethics class, the students come to know that the human relations behind the case make ethical matters more complicated. Furthermore, they come to understand that facilitating daily communications with co‐workers and/or supervisors is very important in order to avoid such accidents. The recognition of the students is primarily the result of the continuous education during 3 years. It can be said that the engineering ethics education thus constructed increases in the students this kind of spontaneous awareness as well as their ethical qualities as engineers. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(3): 1–8, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22283 相似文献
83.
Crack growth behaviour under static and cyclic loading was investigated using anisotropic plates of PMMA oriented by hot-stretching. Both tests were performed at room temperature for samples with different degrees of orthotropy. A slight increase in the degree of orthotropy considerably improves the resistance to both static and cyclic crack growth in the case where the crack propagates perpendicularly to the hot-stretched direction. A power law relationship between crack growth rate and stress intensity factor may hold for both types of crack growth in the ranges of orthotropy tested. The experimental data for static crack growth were compared with a viscoelastic criterion based on the crack opening displacement theory for fracture. The criterion discussed here explains comparatively not only the beginning of cracking from a pre-introduced crack, but also the crack growth rate in oriented PMMA. 相似文献
84.
85.
S Nomura T Orita T Tsurutani K Kajiwara A Izumihara 《Canadian Metallurgical Quarterly》1997,21(6):351-353
The study of a modified minilaparotomy technique of interval female sterilization is reported. The modified minilaparotomy technique of interval female sterilization is performed under local anesthesia using the Ramathibodi uterine manipulator, bivalve speculum, and a low midline incision. Sixty cases were treated with this technique. From the study, it was revealed that the mean age of patients +/- SD was 31.2 +/- 5.6 years, the mean body weight +/- SD was 43.3 +/- 5.1 kg, and the mean height +/- SD was 152.1 +/- 8.2 cm. The mean operating time was 24.3 +/- 5.5 min with a range from 15 to 35 min. All patients recovered and were allowed home within 2 h after operation. No immediate or late complications were observed. It was concluded that this technique is quick, safe, inexpensive, and easy to perform as an outpatient procedure. 相似文献
86.
We have demonstrated a novel heterostructure device with functions of both a semiconductor laser and a heterojunction bipolar transistor, which is applicable to highly multifunctional optoelectronic integrated circuits. It can control both lasing power and output current. CW operation of the InGaAsP/InP transverse current injection laser at around room temperature has been achieved for the first time. 相似文献
87.
Fatty acid hydroperoxide lyase (HPO lyase) is an enzyme that cleaves hydroperoxides of polyunsaturated fatty acids to form short chain aldehydes and omega-oxoacids. Spectrophotometric analyses of HPO lyase highly purified from green bell pepper fruits indicate that it is a heme protein. The heme species was revealed to be heme b (protoheme IX) from the absorption spectrum of the pyridine hemochromogen. Although the spectrum highly resembles that of a plant cytochrome P450, allene oxide synthase from flaxseed, CO treatment of the enzyme caused no appearance of a peak at 450 nm, which is an essential diagnostic feature of a cytochrome P450. Internal amino acid sequences determined with peptide fragments obtained from the lyase showed no homology with any reported sequences. 相似文献
88.
This paper presents an anti-multipath fading scheme employing a circular polarized wave for line-of-sight (LOS) indoor radio communications. The circular polarized wave transmission/reception significantly mitigates the multipath fading caused by reflections from walls, ceiling, and floor since the energies of single-bounce reflected waves do not appear at the receiver, thereby resulting in significant amplitude fade and delay spread reduction. The received signal intensity variations and delay spread are investigated numerically using a 14-path propagation model and the usefulness is confirmed by comparing with a linear polarized wave transmission/reception under a same LOS condition 相似文献
89.
H. Taniguchi H. Sannomiya K. Kajiwara K. Nomoto Y. Yamamoto K. Hiyoshi H. Kumada M. Murakami T. Tomita 《Solar Energy Materials & Solar Cells》1997,49(1-4)
The surface morphology and the optical property of sandblasted glasses and the photovoltaic property of amorphous-silicon solar cells fabricated on them were investigated. The results suggest that the cell performance is related to the surface micro roughness of glass substrate, especially the short period undulation and the surface fractal dimension. Consequently, the amorphous-silicon solar cell on the tempered glass substrate which had the short-circuit current of 14.26 mA/cm2 and the efficiency of 8.00% was obtained. 相似文献
90.
N Yanagihara K Hara K Kajiwara K Minami Y Toyohira Y Uezono S Ueno H Hirano U Yamashita F Izumi 《Canadian Metallurgical Quarterly》1998,243(1-3):25-28
The effects of lymphocytes and their conditioned medium on catecholamine efflux and uptake were examined in cultured bovine adrenal medullary cells. Co-culture of adrenal medullary cells with lymphocytes for 3 days caused an increase in appearance of catecholamines in the culture medium. Treatment of adrenal medullary cells with a conditioned medium prepared from lymphocytes also enhanced the appearance of catecholamines in culture medium in time- (8-48 h) and concentration-dependent manners. Heat treatment of the conditioned medium at 60 and 100 degrees C for 10 min reduced its stimulatory effect to 59 and 20% of control, respectively. After gel filtration on a Sephadex G-25 column or dialysis (<8 kDa molecular mass cutoff), the stimulatory activity of the conditioned medium was found in a high molecular fraction. The conditioned medium had little effect on the activity of lactate dehydrogenase in the medium of cultured adrenal medullary cells and on desipramine-sensitive [3H]norepinephrine uptake by the cells. These findings suggest that lymphocytes release a heat-sensitive factor(s) (molecular mass of more than 8 kDa) which increases efflux of catecholamines from cultured adrenal medullary cells. 相似文献