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71.
With the fast development, in the last ten years, of a large choice of set-ups dedicated to routine in vivo measurements in rodents, fluorescence imaging techniques are becoming essential tools in preclinical studies. Human clinical uses for diagnostic and image-guided surgery are also emerging. In comparison to low-molecular weight organic dyes, the use of fluorescent nanoprobes can improve both the signal sensitivity (better in vivo optical properties) and the fluorescence biodistribution (passive "nano" uptake in tumours for instance). A wide range of fluorescent nanoprobes have been designed and tested in preclinical studies for the last few years. They will be reviewed and discussed considering the obstacles that need to be overcome for their potential everyday use in clinics. The conjugation of fluorescence imaging with the benefits of nanotechnology should open the way to new medical applications in the near future. 相似文献
72.
Ion Grosu Loïc Toupet Gerard Plé Sorin Mager Eugen Mesaros Andreea Varga Elena Bogdan 《Monatshefte für Chemie / Chemical Monthly》2000,131(3):277-286
Summary. The synthesis and stereochemistry of new dibrominated spiro-1,3-dioxane derivatives are reported. Investigations by means
of NMR methods and single crystal X-ray diffraction for two compounds revealed the high regio- and diastereoselectivity of
the bromination reaction of some new spiro-1,3-dioxanes and the asymmetric induction of the chiral carbon atom located in
the spiro skeleton.
Received July 13, 1999. Accepted October 21, 1999 相似文献
73.
Mathilde Briday Franois Hall Lauriane Lecoq Sylvie Radix Juliette Martin Roland Montserret Marie Dujardin Marie-Laure Fogeron Michael Nassal Beat H. Meier Thierry Lomberget Anja Bckmann 《Chemical science》2022,13(30):8840
Hepatitis B virus (HBV) is a small enveloped retrotranscribing DNA virus and an important human pathogen. Its capsid-forming core protein (Cp) features a hydrophobic pocket proposed to be central notably in capsid envelopment. Indeed, mutations in and around this pocket can profoundly modulate, and even abolish, secretion of enveloped virions. We have recently shown that Triton X-100, a detergent used during Cp purification, binds to the hydrophobic pocket with micromolar affinity. We here performed pharmacomodulation of pocket binders through systematic modifications of the three distinct chemical moieties composing the Triton X-100 molecule. Using NMR and ITC, we found that the flat aromatic moiety is essential for binding, while the number of atoms of the aliphatic chain modulates binding affinity. The hydrophilic tail, in contrast, is highly tolerant to changes in both length and type. Our data provide essential information for designing a new class of HBV antivirals targeting capsid–envelope interactions.Small-molecule binding to the Hepatitis B virus core protein hydrophobic pocket, a possible strategy for targeting viral particle assembly. 相似文献
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76.
The infrared spectrum of gaseous cyclopropane has been measured in the regions 980–1080 and 1400–1500 cm?1, containing the ν10 and ν9E′ fundamental bands, respectively, using a high-resolution Fourier transform instrument. Deconvolution was used to enhance the resolution in the crowded parts of the spectrum to ~0.0020–0.0025 cm?1. Apart from the rotational l-resonance affecting mainly the low-K subbands, the ν9 band is strongly perturbed by Fermi resonance with the 2ν142 state lying ~41 cm?1 above. The effects of the Fermi resonance are most pronounced in the high-KΔK = +1 subbands as the 2ν14?2 levels would cross the ν9+ levels near K = 30. rR lines of 2ν14?2 for K = 24 to 36, enhanced by the resonance, have been identified in the region 1469–1475 cm?1 of the spectrum. Two extra perturbation-enhanced subbands are found adjacent to the K = 16?17 and K = 17?16 subbands of ν9: these have been ascribed to the K = 18?17 transitions in 2ν14?2 and to the K = 19?16 transitions in , respectively, as their upper states coincide with the corresponding levels ν9?(K = 16) and ν9+(K = 17). A combination of l-resonance and Fermi resonance is mainly responsible for the interactions causing the perturbations and appearance of the extra subbands, but a direct rotational interaction 〈ν9?(K)|h3|2ν14?2(K + 2)〉 also had to be introduced to accurately account for the observations. In contrast, the ν10 band is not appreciably perturbed by other states and merely exhibits effects of strong l-resonance in the low-K subbands, and K-doubling of the high-J lines of the K = 2–3 subband. A detailed analysis of the spectrum and of the perturbations is described and sets of accurate spectroscopic constants are reported for ν10 and ν9 as well as for the perturbing state 2ν142, which reproduce 3020 observed lines of the ν10 band with a standard deviation of 0.0008 cm?1 and 1810 lines of ν9 with a standard deviation of 0.0010 cm?1. 相似文献
77.
Pl. Muthuramalingam 《Mathematische Nachrichten》1986,127(1):145-163
We prove asymptotic completeness using ENSS' method for h0(P) + WS(Q) + WL(Q) where h0: Rn → R is a polynomial of degree 2 with lim lim|ξ|→∞h0(ξ)| + |Δh0(ξ)| = ∞, WS a short range potential and WL a smooth long range potential. 相似文献
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79.
Souhir Boujday Dr. Juliette Blanchard Dr. Richard Villanneau Dr. Jean‐Marc Krafft Christophe Geantet Prof. Catherine Louis Dr. Michèle Breysse Dr. Anna Proust Prof. 《Chemphyschem》2007,8(18):2636-2642
We use polyoxometalates as precursors for the preparation of heterogeneous catalysts. In the starting molecular precursor [{Ru(C6Me6)}2Mo5O18{Ru(C6Me6)(H2O)}], three ruthenium arene fragments are supported on a formally lacunary Lindqvist‐type polyoxomolybdate. This species was introduced by incipient wetness impregnation into the porosity of a SBA‐15‐type mesoporous silica. The evolution of the system under reducing atmosphere is followed by several methods, such as temperature‐programmed reduction (TPR), Raman, and X‐ray absorption spectroscopy (XAS). The results indicate that the polyoxometalate structure is retained after grafting on silica and allows the stabilization of Ru0 nanoparticles after reduction. The resulting system exhibits interesting catalytic activity in benzene hydrogenation. 相似文献
80.