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971.
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Claudio Luchinat 《Angewandte Chemie (International ed. in English)》2012,51(42):10445-10445
974.
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A Semisynthetic Approach to New Immunoadjuvant Candidates: Site‐Selective Chemical Manipulation of Escherichia coli Monophosphoryl Lipid A 下载免费PDF全文
Dr. Daniele D'Alonzo Manuela Cipolletti Giulia Tarantino Marcello Ziaco Dr. Giuseppina Pieretti Prof. Alfonso Iadonisi Prof. Giovanni Palumbo Dr. Alberto Alfano Dr. Mariateresa Giuliano Prof. Mario De Rosa Prof. Chiara Schiraldi Dr. Marcella Cammarota Prof. Michelangelo Parrilli Dr. Emiliano Bedini Prof. Maria M. Corsaro 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):11053-11063
A semisynthetic approach to novel lipid A derivatives from Escherichia coli (E. coli) lipid A is reported. This methodology stands as an alternative to common approaches based exclusively on either total synthesis or extraction from bacterial sources. It relies upon the purification of the lipid A fraction from fed‐batch fermentation of E. coli, followed by its structural modification through tailored, site‐selective chemical reactions. In particular, modification of the lipid pattern and functionalization of the phosphate group as well as of the sole primary hydroxyl group were accomplished, highlighting the unusual reactivity of the molecule. Preliminary investigations of the immunostimulating activity of the new semisynthetic lipid A derivatives show that some of them stand out as promising, new immunoadjuvant candidates. 相似文献
976.
Pavel Bedrikovetsky Fernando D. Siqueira Claudio A. Furtado Antonio Luiz S. Souza 《Transport in Porous Media》2011,86(2):353-383
Particle detachment from the rock during suspension transport in porous media was widely observed in laboratory corefloods
and for flows in natural reservoirs. A new mathematical model for detachment of particles is based on mechanical equilibrium
of a particle positioned on the internal cake or matrix surface in the pore space. The torque balance of drag, electrostatic,
lifting and gravity forces, acting on the particle from the matrix and the moving fluid, is considered. The torque balance
determines maximum retention concentration during the particle capture. The particle torque equilibrium is determined by the
dimensionless ratio between the drag and normal forces acting on the particle. The maximum retention function of the dimensionless
ratio (dislodging number) closes system of governing equations for colloid transport with particle release. One-dimensional
problem of coreflooding by suspension accounting for limited particle retention, controlled by the torque sum, allows for
exact solution under the assumptions of constant filtration coefficient and porosity. The explicit formulae permit the calculation
of the model parameters (maximum retention concentration, filtration and formation damage coefficients) from the history of
the pressure drop across the core during suspension injection. The values for maximum retention concentration, as obtained
from two coreflood tests, have been matched with those calculated by the torque balance on the micro scale. 相似文献
977.
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Mahdi Sadeghi Omid Kiavar S. Hamed Hosseini Rozhin Fatehi Claudio Tenreiro 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):565-571
The Nitinol stent was bombarded in a cyclotron at a flux rate of 4 μA/cm2 to produce 48V via 48Ti (p, n) 48V reaction. In this study dose distribution of 48V radioactive stent was investigated for renal arteries. Version X-2.6 of the MCNP Monte Carlo radiation transport system
code was employed to calculate dose distribution around the stent. As 48V is a mixed gamma and beta particle emitter, two separate runs of MCNP for both beta and gamma particles were performed and
the total deposited dose was acquired by adding the two mentioned values. In order to verify the simulation, the calculated
results have been compared with previous published data for the source. Calculated results show high dose gradient near the
stent and the maximum amount of dose deposits at the vessel wall. According to (AAPM) TG-60/149 protocol, the dosimetric parameters,
including geometry function, G(ρ,z), radial dose function, g
L
(ρ), and anisotropy function, F(ρ,z), were also determined. 相似文献
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980.