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91.
The coenzyme specificity of 3isopropylmalate dehydrogenasefrom an extreme thermophile, Thermus thermophilus HB8, was changedfrom NAD to NADP by sitedirected mutagenesis Based onsequence comparison of 3isopropylmalate dehydrogenasesfrom various organisms with NAD and NADPdependentisocitrate dehydrogenases, Ser226, Ser253 and De279 of 3isopropylmalatedehydrogenase were suggested as determining the coenzymespecificity. These residues were replaced with the correspondingresidues of NADPdependent isocitrate dehydrogenases;Arg, Gly and Tyr respectively. The singlemutated enzymes,S226R and I279Y, enhanced the activities towards NADP 10and 3fold respectively, whereas S253G reduced the activity.Among the multiplemutated enzymes, the doublemutatedS226R/I279Y increased the catalytic efficiency against NADP( fold) and shifted the specificity for NAD towards NADP mostsignificantly ( 173fold). 相似文献
92.
Sensory evaluation of beef patties and sausages containing lipids with various component fatty acids 总被引:1,自引:0,他引:1
Sensory scores of beef patties and emulsion-type sausages containing varying levels of lipids with various component fatty acids were investigated. Sensory scores of beef patties containing solid fat were relatively constant at every fat level examined. However, scores of beef patties containing liquid oil decreased with increasing level of added oil. In the case of sausages, on the other hand, sensory evaluation scores markedly decreased with increasing the level of solid fat, while no significant change was observed in panel scores when liquid oil was mixed into sausages. Even 10% level of added lipids satisfactorily gave preferable acceptability to beef patties and sausages. 相似文献
93.
Tamada Tsutomu Ueda Yu Kido Ayumu Yoneyama Masami Takeuchi Mitsuru Sanai Hiroyasu Ono Kentaro Yamamoto Akira Sone Teruki 《Magma (New York, N.Y.)》2022,35(4):549-556
Magnetic Resonance Materials in Physics, Biology and Medicine - Image quality (IQ) of diffusion-weighted imaging (DWI) with single-shot echo-planar imaging (ssEPI) suffers from low signal-to-noise... 相似文献
94.
95.
Correlation between Chemical Dopants and Topological Defects in Catalytically Active Nanoporous Graphene 下载免费PDF全文
96.
AIM: To introduce the "starlight" test which was devised to check binocular vision in normal conditions of seeing in a rapid, easy, and cost effective manner and to estimate the possibility of its clinical use in screening the binocular visual field of patients. METHOD: The Bagolini striated glass test consists of optically plano lenses with imperceptible parallel scratches that barely blur the environment but produce two perpendicular luminous stripes (right eye stripe of 45 degrees and left eye stripe of 135 degrees) when subjects with normal binocular vision view one light source. Unlike the original Bagolini test, the starlight test uses three light sources in horizontal or vertical lines according to the testing purposes and the subject is asked to fixate upon the centre light. Through Bagolini glasses, the subject observes the resulting grid-like pattern and the state of binocular visual field of the subject can be roughly estimated. RESULTS: Normal subjects and patients with strabismus, visual field loss from intracranial diseases, glaucoma, retinitis pigmentosa, and functional visual loss were examined using the starlight test and findings from each case were discussed. CONCLUSIONS: The starlight test, which was made by hand at a low cost, is a simple test that can be used clinically. It provides information about the state of binocular vision of patients in normal conditions of seeing. It is also useful because it enables the examiner to share similar experiences with the examinee. The results suggest it can be effective in visual field screening. 相似文献
97.
Research findings and various published studies point to interleukin 4 (IL-4) and CD23 antigen as instrumental in allergic reactions of allergy patients because these two substances are part of the main triggering mechanisms in cells producing IgE antibodies. In this study it was investigated whether the control of IL-4 and CD23 levels result in a decrease of the severity of allergic reactions. It is well known that azelastine hydrochloride (AZ, CAS 79307-93-0) suppresses symptoms of nasal allergy. The antiallergic activity of this drug includes the suppression of IgE antibody production, antigen-antibody reactions, liberation of mediators and mediator antagonism. One report states that the cytokines IL-2, IL-3, and IL-4 were suppressed by AZ in cultured cells. There have been no reports regarding cytokines in clinical treatment using AZ. Therefore, the effects of AZ treatment on IL-4, soluble CD23, and RAST (radioallergosorbent test) levels in the sera of allergic rhinitis patients were studied. The results show that the levels of IL-4 and soluble CD23 were significantly reduced by the administration of AZ over a 4-week period, especially in patients with "excellent" or "good" efficacy of therapy. 相似文献
98.
Kazushi Yawata Daisuke Ito Hiroki Ikegami Hidehiko Ishimoto Hiroshi Fukuyama 《Journal of Low Temperature Physics》1998,113(5-6):769-774
Experimental methods and preliminary results of high-precision measurements of the
3
He melting curve in high magnetic fields have been described. The purpose of this work is twofold. One is to establish a reliable millikelvin temperature scale in high fields (T 10 mK, B 15 T), The other is to investigate a high field region of the magnetic phase diagram of solid
3
He by measuring the melting pressure down to temperatures below 1 mK. Besides the two superfluid transitions, the phase transition temperatures between the spin ordered solid and the paramagnetic solid, T
HFP
, were determined at B = 12 and 10 T with good accuracy, which is an extension of previous measurements up to 8 T. The present T
HFP
(B) line can not be scaled to that at a higher density with a single Grüneisen parameter, indicating a variation of density dependencies of the multiple-spin exchange interactions. 相似文献
99.
Takayuki Ito Hiroyuki Yamaguchi Katsuya Okabe Taizo Masumi 《Journal of Materials Science》1998,33(14):3555-3566
We have prepared a large number of crystals of cuprous oxide (Cu2O) by various procedures. Photoluminescence spectra of these crystals were studied to examine the concentration of defects, especially copper vacancy VCu to seek favourable conditions for growing Cu2O crystal. High-quality single crystals of Cu2O were prepared by the floating-zone melting method in air. Several synthetic crystals (specimens FA, FZ and GZ) and also a natural crystal were studied by X-ray analysis, inductively coupled plasma spectroscopy analysis, optical absorption, photoluminescence, photoconductivity and cyclotron resonance absorption, photoluminescence, photoconductivity and cyclotron resonance absorption to characterize their optical and electrical qualities. The best values of mobility and scattering time of photocarriers at T = 4.2 K are estimated to be h1.8 × 105 cm2 V–1 s–1 and h60 ps for positive holes, and 1.3 × 105 cm2 V–1 s–1 and 70 ps for electrons in Cu2O. Further, we report preliminary experimental results on transport property of crystals also of cupric oxide (CuO) purified by the floating-zone melting method. 相似文献
100.
Kazuto Okazaki Tatsuya Ogiwara Dongshin Yang Kentaro Sakata Ken Saito Yoshifumi Sekine Fumio Uchikoba 《Artificial Life and Robotics》2011,16(2):229-233
This article presents the micro-electro-mechanical systems (MEMS) microrobot which demonstrates locomotion controlled by hardware
neural networks (HNN). The size of the microrobot fabricated by the MEMS technology is 4 × 4 × 3.5 mm. The frame of the robot
is made of silicon wafer, and it is equipped with a rotary-type actuator, a link mechanism, and six legs. The rotary-type
actuator generates rotational movement by applying an electrical current to artificial muscle wires. The locomotion of the
microrobot is obtained by the rotation of the rotary-type actuator. As in a living organism, the HNN realized robot control
without using any software programs, A/D converters, or additional driving circuits. A central pattern generator (CPG) model
was implemented as an HNN system to emulate the locomotion pattern. The MEMS microrobot emulated the locomotion method and
the neural networks of an insect with the rotary-type actuator, the link mechanism, and the HNN. The microrobot performed
forward and backward locomotion, and also changed direction by inputting an external trigger pulse. The locomotion speed was
0.325 mm/s and the step width was 1.3 mm. 相似文献