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排序方式: 共有159条查询结果,搜索用时 196 毫秒
91.
Daisuke Kawaguchi Ayumi Kodama Naoko Abe Kei Takebuchi Fumitaka Hashiya Fumiaki Tomoike Kosuke Nakamoto Yasuaki Kimura Yoshihiro Shimizu Hiroshi Abe 《Angewandte Chemie (International ed. in English)》2020,59(40):17403-17407
Messenger RNAs (mRNAs) with phosphorothioate modification (PS‐mRNA) to the phosphate site of A, G, C, and U with all 16 possible combinations were prepared, and the translation reaction was evaluated using an E. coli cell‐free translation system. Protein synthesis from PS‐mRNA increased in 12 of 15 patterns when compared with that of unmodified mRNA. The protein yield increased 22‐fold when the phosphorothioate modification at A/C sites was introduced into the region from the 5′‐end to the initiation codon. Single‐turnover analysis of PS‐mRNA translation showed that phosphorothioate modification increases the number of translating ribosomes, thus suggesting that the rate of translation initiation (rate of ribosome complex formation) is positively affected by the modification. The method provides a new strategy for improving translation by using non‐natural mRNA. 相似文献
92.
Large Amplitude Motion in 9-Methylanthracene: High-Resolution Spectroscopy and Ab Initio Theoretical Calculation 下载免费PDF全文
Masaaki Baba Ayumi Kanaoka Akiko Nishiyama Masatoshi Misono Takayoshi Ishimoto Taro Udagawa 《化学物理学报(中文版)》2020,33(1):8-12
CH\begin{document}$_3$\end{document} internal rotation is one of the typical large amplitude motions in polyatomic molecules, the spectral analysis and theoretical calculations of which, were developed by Li-Hong Xu and Jon Hougen. We observed a Doppler-free high-resolution and high-precision spectrum of 9-methylanthracene (9MA) by using the collimated supersonic jet and optical frequency comb techniques. The potential energy curve of CH\begin{document}$_3$\end{document} internal rotation is expressed by a six-fold symmetric sinusoidal function. It was previously shown that the barrier height (\begin{document}$V_6$\end{document} ) of 9MA-\begin{document}$d_{12}$\end{document} was considerably smaller than that of 9MA-\begin{document}$h_{12}$\end{document} [M. Baba, et al., J. Phys. Chem. A 113 , 2366 (2009)]. We performed ab initio theoretical calculations of the multi-component molecular orbital method. The barrier reduction by deuterium substitution was partly attributed to the difference between the wave functions of H and D atomic nuclei. 相似文献
93.
Hiroshi Konno Yasutoshi Yajima Ayumi Ban 《Computational Optimization and Applications》1994,3(2):181-191
We will propose an algorithm for calculating a minimal sphere containing a polytope defined by a system of linear inequalities in low dimensional Euclidean space. This algorithm is a straightforward application of the algorithm for maximizing a convex quadratic function over a polytope. It will be shown that this algorithm successfully generates a minimal sphere when the dimensions of the underlying space is up to five.International Digital Communication Inc. 相似文献
94.
Satoh T Sato T Kubo A Tamura J 《Journal of the American Society for Mass Spectrometry》2011,22(5):797-803
In this study, we have developed a tandem time-of-flight mass spectrometry (TOF/TOF) technique involving the use of a matrix-assisted
laser desorption/ionization ion source that exhibits high precursor ion selectivity. An ion optical system with a 17 m spiral
ion trajectory was used in the first time-of-flight mass spectrometer. High precursor ion selectivity was achieved by realizing
a 15 m flight path, which is considerably longer than that of the conventional MALDI-TOF/TOF before the precursor ion selection
by an ion gate; monoisotopic ions could be selected properly up to m/z 2500. Furthermore, the first time-of-flight mass spectrometer was composed of electrostatic sectors and could eliminate post-source
decay (PSD) ions. Precursor ions with 20 keV kinetic energy were selected and injected into a collision cell, leading to the
generation of fragment ions by high-energy collision-induced dissociation (HE-CID). The optimized second time-of-flight mass
spectrometer included a post-acceleration region and an offset parabolic reflectron to record product ion spectra in the entire
mass range. Our system could generate a simple HE-CID product ion spectrum because each fragment pathway could be observed
as a single peak by the selection of monoisotopic ions of all precursor ions and HE-CID fragment pathways could be predominantly
observed by the PSD ion elimination. 相似文献
95.
Menaa F Braghini CA Vasconcellos JP Menaa B Costa VP Figueiredo ES Melo MB 《Molecules (Basel, Switzerland)》2011,16(7):5402-5421
MYOC encodes a secretary glycoprotein of 504 amino acids named myocilin. MYOC is the first gene to be linked to juvenile open-angle glaucoma (JOAG) and some forms of adult-onset primary open-angle glaucoma (POAG). The gene was identified as an up-regulated molecule in cultured trabecular meshwork (TM) cells after treatment with dexamethasone and was originally referred to as trabecular meshwork-inducible glucocorticoid response (TIGR). Elevated intraocular pressure (IOP), due to decreased aqueous outflow, is the strongest known risk factor for POAG. Increasing evidence showed that the modulation of the wild-type (wt) myocilin protein expression is not causative of glaucoma while some misfolded and self-assembly aggregates of mutated myocilin may be associated with POAG in related or unrelated populations. The etiology of the disease remains unclear. Consequently, a better understanding of the molecular mechanisms underlying POAG is required to obtain early diagnosis, avoid potential disease progression, and develop new therapeutic strategies. In the present study, we review and discuss the most relevant studies regarding structural characterizations, expressions, molecular interactions, putative functions of MYOC gene and/or its corresponding protein in POAG etiology. 相似文献
96.
97.
We report a unique class of dinitrogen complexes of iron featuring sulfur donors in the ancillary ligand. The ligands utilized are related to the recently studied tris(phosphino)silyl ligands (2-R(2)PC(6)H(4))(3)Si (R = Ph, iPr) but have one or two phosphine arms replaced with thioether donors. Depending on the number of phosphine arms replaced, both mononuclear and dinuclear iron complexes with dinitrogen are accessible. These complexes contribute to a desirable class of model complexes that possess both dinitrogen and sulfur ligands in the immediate iron coordination sphere. 相似文献
98.
Four new Erythrinan alkaloids (1-4) were isolated from the seeds of Erythrina velutina. The structures of these new compounds 1-4 were elucidated by spectroscopic methods including 2D-NMR. Three of four were found to be novel sulfated Erythrinan alkaloids. 相似文献
99.
Toshio Nishino Yasuyuki Yamada Ayumi Yamamoto Kentaro Tanaka 《Molecules (Basel, Switzerland)》2021,26(4)
A novel double-decker porphyrin complex, bis{meso-tetrakis(4-N-alkylpyridiniumyl)porphyrinato}cerium, was prepared. Electrochemical measurements revealed that this complex exhibited reversible redox waves corresponding to a 1e– redox reaction of the cerium center. Treating the complex alternately with an oxidant and a reductant resulted in the reversible redox switching between the oxidized and reduced states in an organic solvent. 相似文献
100.
Sharma Gyanendra Kato Yui Hachisu Ayumi Ishibashi Kojiro Ninomiya Kazuaki Takahashi Kenji Hirata Eishu Kuroda Kosuke 《Cellulose (London, England)》2022,29(5):3017-3024
Cellulose - A carboxylate-type liquid zwitterion, OE2imC3C, has been recently reported as a unique solvent as a class of ionic liquids with distinctive properties and functions such as cellulose... 相似文献