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991.
992.
Kurasaki M; Yamaguchi R; Linde Arias AR; Okabe M; Kojima Y 《Protein engineering, design & selection : PEDS》1997,10(4):413-416
In order to evaluate the significance of alpha- and beta-fragments of
metallothionein with regard to Cd binding in biosynthetic processes, the
Cd-binding ability of four mutant metallothioneins was examined using the
Escherichia coli expression system. The features of the mutant
metallothioneins were proteins in which cysteine residues in the alpha- or
beta-fragment were replaced with alanine residues, or that the sequential
order of the fragments was altered. The expressed mutant metallothioneins
having an intact alpha-fragment showed the constructive abilities of the
Cd-thiolate cluster. On the other hand, mutant metallothionein having an
alpha-fragment lacking metal-binding sites exhibited no Cd-binding ability.
The condition for maintaining the Cd-binding capability of metallothionein
was that the alpha- fragment remains intact irrespective of the sequential
order of the two fragments. The alpha-fragment is an indispensable
component in metal- binding processes of Cd-metallothionein.
相似文献
993.
A differential optical switch based on parallel-connected AlGaAs-GaAs pnpn structures is presented. Continuous input light makes it possible to discriminate between two optical inputs with a power difference of as low as 0.1 nW. The minimum operating energy with pulse inputs was 400 fJ. With the introduction of a storage operation of pnpn structures, the optical S -R flip-flop operation is also demonstrated with a 7.2-pJ optical input energy. The expansibility of the 2-D array is attractive in optical parallel processing systems, especially in optical neural networks 相似文献
994.
Design experience of the base-isolated new computer center of the Tohoku Electric Power Co. is described. This building after completion will be the largest isolated building in Japan with a total floor space of ≈10,000m2. High-damping laminated rubber bearings are used as base-isolation devices. 相似文献
995.
A new transmission electron microscope that allows for stereoscopic observations in real time at a video rate has been developed. In order to make stereo pairs at a high speed, illumination of a specimen from two directions instead of specimen tilting is adopted. Two electrostatic deflectors make it possible to alternate the illumination direction within a blank period of 1.2 ms between two adjacent video fields. Three dimensional displays give observers a stereo impression without the need for special glasses. By considering the circle of least confusion due to spherical aberration, a lateral resolution <1 nm and a longitudinal resolution of 6.3 nm are possible with a proper defocused condition. This improvement of the resolution is confirmed for the image of Au fine particles. The motion of objects in the lateral direction can be detected up to a speed of 8.3 nm s(-1). Using this microscope fine particles of ZnO were observed. 相似文献
996.
Kojima M Shioiri H Nogawa M Nozue M Matsumoto D Wada A Saiki Y Kiguchi K 《Journal of Bioscience and Bioengineering》2004,98(2):136-139
Kenaf was transformed by inoculation of Agrobacterium tumefaciens onto the meristems of young plants in pots. The transformation was demonstrated by three lines of evidence: a phenotypic inheritance from T(0) to T(1) plants, detection of the transgene in both T(0) and T(1) plants, and rescue of plasmids composed of T-DNA of the binary vector and flanking plant genomic DNA from T(1) plants. 相似文献
997.
998.
High-resolution 3-D shape integration of dentition and face measured by new laser scanner 总被引:1,自引:0,他引:1
Sohmura T Nagao M Sakai M Wakabayashi K Kojima T Kinuta S Nakamura T Takahashi J 《IEEE transactions on medical imaging》2004,23(5):633-638
Face and dentition were measured using a high-resolution three-dimensional laser scanner to circumvent problems of radiation exposure and metal-streak artifacts associated with X-ray computed tomography. The resulting range data were integrated in order to visualize the dentition relative to the face. The acquisition interval for dentition by laser scanner was 0.18 mm, and complicated morphologies of the occlusal surface could be sufficiently reproduced. Reproduction of occlusal condition of upper and lower dentitions was conducted by matching the surface of the occlusal impression record with upper dentition data. To integrate dentition and face, a marker plate interface was devised and adopted on the lower dental cast or by the subject directly. Integration was performed by matching both sets of interface data. Reproduction of the occlusal condition and integration of the dentition and face were accomplished and visualized satisfactorily by computer graphics. The integration accuracy was examined by changing the attachment angle of the marker plate, and the marker plate attached at 45 degrees showed the smallest error of 0.2 mm. The current noninvasive method is applicable to clinical examination, diagnosis and explanation to the patient when dealing with the physical relationship between face and dentition. 相似文献
999.
1000.
Magnetic properties of SmFe10(Ti,M )2 melt-spun ribbons were studied, where M is V, Cr, Mn, and Mo. The ribbons (M =V/Cr/Mo) quenched at 20 m/s exhibit the high coercivities of 4.2-5.5 kOe. Annealing the ribbons quenched at 40 m/s enhances their coercivities in the range of 5.9-10.0 kOe. In particular, SmFe10 (TiV) and SmFe10(TiCr) ribbons yield coercivities of 10.0 kOe and 7.9 kOe, respectively. This is the highest value among the reported melt-spun ThMn12-type structure ribbons. The importance of Sm atmosphere during annealing in minimizing the Sm evaporation from ribbons is also demonstrated 相似文献