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71.
Russian Journal of Bioorganic Chemistry - DNA-substrates containing fluorescent DNA base analogs are widely used to study protein–nucleic acid interactions. In the case of DNA-recognizing...  相似文献   
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A detailed protocol for the synthesis of core/shell semiconductor nanocrystal, their encapsulation into phospholipid micelles, their purification and their coupling to a controlled number of small molecules is given. The protocol for the core/shell quantum dot (QD) CdSe/CdZnS synthesis has been specifically designed with two constraints in mind: green and reproducible core/shell QD synthesis with thick shell structure and QDs that can easily be encapsulated in poly(ethylene glycol)-phospholipid micelles with one QD per micelle. We present two procedures for the QD purification that are suitable for the use of QD micelles for in vivo imaging: ultracentrifugation and size-exclusion chromatography. We also discuss the different coupling chemistry for covalently linking a controlled number of molecules to the QD micelles. The total time durations for the different protocols are as follows: QD synthesis: 6 h; encapsulation: 15 min; purification: 1-4 h; coupling: reaction dependent.  相似文献   
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We present a new non-rigid registration algorithm estimating the displacement field generated by articulated bodies. Indeed the bony structures between different patient images may rigidly move while other tissues may deform in a more complex way. Our algorithm tracks the displacement induced in the column by a movement of the patient between two acquisitions. The volumetric deformation field in the whole body is then inferred from those displacements using a linear elastic biomechanical finite element model. We demonstrate in this paper that this method provides accurate results on 3D sets of computed tomography (CT), MR and positron emission tomography (PET) images and that the results of the registration algorithm show significant decreases in the mean, min and max errors.  相似文献   
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It is well known that simultaneous presentation of incongruent audio and visual stimuli can lead to illusory percepts. Recent data suggest that distinct processes underlie non-specific intersensory speech as opposed to non-speech perception. However, the development of both speech and non-speech intersensory perception across childhood and adolescence remains poorly defined. Thirty-eight observers aged 5 to 19 were tested on the McGurk effect (an audio-visual illusion involving speech), the Illusory Flash effect and the Fusion effect (two audio-visual illusions not involving speech) to investigate the development of audio-visual interactions and contrast speech vs. non-speech developmental patterns. Whereas the strength of audio-visual speech illusions varied as a direct function of maturational level, performance on non-speech illusory tasks appeared to be homogeneous across all ages. These data support the existence of independent maturational processes underlying speech and non-speech audio-visual illusory effects.  相似文献   
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Beginning in the early 1990s, the balsam fir sawfly (Neodiprion abietis) became a significant defoliating insect of precommercially thinned balsam fir (Abies balsamea (L.) Mill.) stands in western Newfoundland, Canada. In 1997, a nucleopolyhedrovirus (NeabNPV) was isolated from the balsam fir sawfly and, as no control measures were then available, NeabNPV was developed for the biological control of balsam fir sawfly. In order to register NeabNPV for operational use under the Canadian Pest Control Products Act, research was carried out in a number of areas including NeabNPV field efficacy, non-target organism toxicology, balsam fir sawfly ecology and impact on balsam fir trees, and NeabNPV genome sequencing and analysis. As part of the field efficacy trials, approximately 22 500 hectares of balsam fir sawfly-infested forest were aerially treated with NeabNPV between 2000 and 2005. NeabNPV was found to be safe, efficacious, and economical for the suppression of balsam fir sawfly outbreak populations. Conditional registration for the NeabNPV-based product, Abietiv™, was received from the Pest Management Regulatory Agency (Health Canada) in April 2006. In July 2006, Abietiv was applied by spray airplanes to 15 000 ha of balsam fir sawfly-infested forest in western Newfoundland in an operational control program.   相似文献   
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