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61.
Inhibition of HeLa cell messenger RNA translation by 7-methylguanosine 5'-monophosphate 总被引:2,自引:0,他引:2
LA Weber ER Feman ED Hickey MC Williams C Baglioni 《Canadian Metallurgical Quarterly》1976,251(18):5657-5662
Translation of HeLa cell RNA containing poly(A) in a wheat germ cell-free system is markedly but incompletely inhibited by 7-methylguanosine 5'-monophosphate (m7G5'p). We have analyzed the translation products synthesized in the presence of different concentrations of m7G5'p and find that translation of all mRNAs is equally inhibited. To demonstrate the specificity of the inhibitor for RNAs with 5'-terminal m7G5' ppp... we show that specific translation products of satellite tobacco necrosis virus RNA, which does not have this 5' terminus, are synthesized in the presence of m7G5' p. Protein synthesis programmed by endogenous mRNA in a HeLa cell-free system is inhibited after a 10-min lag by m7G5' p. Other guanosine nucleotides without the 7-methyl group or with the phosphate in a different position are not inhibitor. We show that translation of all mRNAs is inhibited to a similar extent by m7G5'p in the HeLa cell-free system, by synthesizing 35S-labeled proteins in the presence of different inhibitory concentrations of this nucleotide and analyzing the translation products by electrophoresis and autoradiography. Translation of encephalomyocarditis virus RNA added to the HeLa cell-free system is not inhibited by m7"g5p; this viral RNA does not have this nucleotide at the 5' terminus. This indicates that m7G5'p specifically inhibits translation of mRNAs with the 5' terminus m7G5'ppp... and suggests that initiation of translation of picornavirus RNA may proceed via a mechanism different from that of cellular mRNAs. 相似文献
62.
E. H. Brandt 《Journal of Low Temperature Physics》1976,24(3-4):409-426
From Gor'kov's theory a functional for the free energy of the flux line lattice is derived which depends explicitly on the potentials andA. It may be interpreted as an extension of the Ginzburg-Landau functional to arbitrary temperatures. For periodic ||
2
andH=rotA, the functional is a rapidly converging series, of which often the main term (corresponding to the Brandt-Pesch-Tewordt approximation) plus a correction term depending on the lattice structure suffices. From the cutoff series all previously known results for the special casesT T
c
,B H
c2
,orB 0 are reproduced by minimization with respect to ||
2
andH. 相似文献
63.
Of 160 patients who underwent Nissen fundoplication for treatment of symptomatic peptic reflux esophagitis, five patients (3.1%) developed gastric ulcers. Four of these five patients experienced the "gas-bloat" syndrome. All ulcers were located on the lesser curvature of the stomach. Analyses of our experience with use of various types of hiatal hernia repair suggests that creation of the valvuloplastic mechanism unique to the Nissen procedure may be of etiologic significance in the development of gastric ulcers following this procedure. 相似文献
64.
S. Rudtsch H. P. Ebert F. Hemberger G. Barth R. Brandt U. Groß W. Hohenauer K. Jaenicke-Roessler E. Kaschnitz E. Pfaff W. Pößnecker G. Pottlacher M. Rhode B. Wilthan 《International Journal of Thermophysics》2005,26(3):855-867
The results of an inter laboratory comparison of thermal conductivity, thermal diffusivity, specific heat capacity, and thermal
expansion measurements on austenitic stainless steel in the temperature range between 20 and 1000°C are presented here. Mean
values are presented for the physical properties studied. Reliable relative expanded uncertainties can be stated for the properties
determined, which were achieved by applying good measurement practice, i.e., 3% for thermal expansion, 5% for specific heat
capacity and thermal diffusivity, and 6% for thermal conductivity. The mean values derived from this intercomparison agree
well with the results of a previous intercomparison in 1990.
An erratum to this article is availabale at . 相似文献
65.
为了更好地辨识和控制非线性动态系统,在FNN基础上对其进行优化和改进,形成了动态模糊神经网络(DFNN)。给出了基于BP梯度算法的参数迭代学习算法,并应用于某非线性动态系统仿真试验中。仿真试验表明,该网络比单纯的FNN具有更强的辨识和控制能力,应用于非线性动态系统的控制中可以有效解决系统的非线性和不确定性,提高系统的跟踪性能,并且控制系统具有很强的鲁棒性。 相似文献
66.
Production Rate‐Dependent Key Performance Indicators for a Systematic Design of Biochemical Downstream Processes 下载免费PDF全文
Key performance indicators have become a common tool in bioprocess development, as they allow an objective and independent rating and ranking of process alternatives screened. A disadvantage of all key performance indicators developed so far is their strong focus on costs, which makes them neglect the influence of the production rate on the profit of the process. But, since both production costs and production rate have an equally strong impact, both should be considered when decisions have to be made. Therefore, two new key performance indicators are introduced in this work, one for batch and one for continuous processing. They combine product yield, purity performance, variable manufacturing costs, and production rate to one objective. Thereby, misguided trade‐offs between these four individual measures can be replaced by one key performance indicator. This ensures a systematic development of biochemical downstream processes. 相似文献
67.
J.J. BorgerS.R. Hashemi-Nezhad D. AlexievR. Brandt W. WestmeierB. Thomauske J. AdamM. Kadykov S. Tiutiunnikov 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2012,664(1):103-110
The Energy plus Transmutation (EpT) set-up of the Joint Institute for Nuclear Research (JINR), Dubna, Russia is composed of a lead spallation target surrounded by a blanket of natural uranium. The resultant neutron spectrum is a combination of spallation and fission spectra, modified by a reflective external layer of polyethylene and an internal absorbing layer of cadmium. The EpT set-up was irradiated with a beam of 4 GeV deuterons from the Nuclotron Accelerator at JINR. The spatial distribution of thorium fission rate within the assembly was determined experimentally, using a fission track detector technique, and compared with Monte Carlo predictions of the MCNPX code. Contributions of neutrons, protons, deuterons, photons and pions to total fission were taken into account. Close agreement between the experimental and calculated results was found. 相似文献
68.
Pleurotus ostreatus laccase recovery from residual compost using aqueous two‐phase systems 下载免费PDF全文
69.
Dr. Yuriy V. Sheludko Dr. Jascha Volk Dr. Wolfgang Brandt Prof. Heribert Warzecha 《Chembiochem : a European journal of chemical biology》2020,21(14):1976-1980
Human drug-metabolizing cytochrome P450 monooxygenases (CYPs) have enormous substrate promiscuity; this makes them promising tools for the expansion of natural product diversity. Here, we used CYP3A4 for the targeted diversification of a plant biosynthetic route leading to monoterpenoid indole alkaloids. In silico, in vitro and in planta studies proved that CYP3A4 was able to convert the indole alkaloid vinorine into vomilenine, the former being one of the central intermediates in the ajmaline pathway in the medicinal plant Rauvolfia serpentina (L.) Benth. ex Kurz. However, to a much larger extent, the investigated conversion yielded vinorine (19R,20R)-epoxide, a new metabolite with an epoxide functional group that is rare for indole alkaloids. The described work represents a successful example of combinatorial biosynthesis towards an increase in biodiversity of natural metabolites. Moreover, characterisation of the products of the in vitro and in planta transformation of potential pharmaceuticals with human CYPs might be indicative of the route of their conversion in the human organism. 相似文献
70.
Howard E. Brandt 《Quantum Information Processing》2012,11(3):787-839
An introduction is first given of recent developments in the Riemannian geometry of quantum computation in which the quantum
evolution is represented in the tangent space manifold of the special unitary unimodular group for n qubits. The Riemannian
right-invariant metric, connection, curvature, geodesic equation for minimal complexity quantum circuits, Jacobi equation,
and the lifted Jacobi equation for varying penalty parameter are reviewed. Sharpened tools for calculating the geodesic derivative
are presented. The geodesic derivative may facilitate the numerical investigation of conjugate points and the global characteristics
of geodesic paths in the group manifold, the determination of optimal quantum circuits for carrying out a quantum computation,
and the determination of the complexity of particular quantum algorithms. 相似文献