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81.
The authors report the relevance of Constrained Spherical Deconvolution (CSD)-based tractography in demonstrating and quantitatively assessing a complex midline structure malformation in a 9-year-old girl with moderate intellectual disability and thickening of corpus callosum (CC) body discovered through conventional MRI (cMRI). Color-encoded fractional anisotropy (FA) maps clearly demonstrated what the cMRI showed as a thicknening of CC: a green, longitudinal bundle running dorsally to the body of CC. A more complex midline maldevelopmental disorder was suspected. CSD-based tractography was performed to virtually dissect the anomalous supracallosal longitudinal bundle (SLB), CC, fornix, anterior commissure (AC) and cingula. In addition, DTI-derived metrics were calculated for each virtually dissected fiber tract.  相似文献   
82.
83.
The multicomponent reaction between 2-naphthol, aryl aldehydes and ammonia or amines yields aminobenzylnaphthols in a process known as the Betti reaction, which was first uncovered at the beginning of the 20th century. The aminobenzylnaphthols could be easily resolved into their enantiomers. After a long silence, the results of our research a decade ago on this useful reaction and on the chiral materials produced has stimulated further work in a number of other laboratories. As a result, novel applications of the Betti reaction to produce new chiral aminobenzylnaphthols were reported together with the evaluation of these chiral bases in asymmetric synthesis. Herein, we present a selection of the relevant studies on this topic.  相似文献   
84.
85.
The adsorption properties of a new nanoporous organic zeolite with respect to acetylene and Ar were studied by volumetric adsorption analysis, microcalorimetric experiments, and synchrotron high-resolution X-ray powder diffraction. This allowed us to locate the guest molecules inside the host channels and characterize the host-guest interactions.  相似文献   
86.
An extensive study was carried out on HSA and non-enzymatically glycated HSA by enzymatic digestion with trypsin and endoproteinase Lys-C, with the aim of identifying specific glycated peptides deriving from enzymatic digestion of glycated HSA. They may be considered, in pectore, as advanced glycation end products/peptides. These compounds, important at a systemic level in diabetic and nephropathic subjects, are produced by enzymatic digestion of in vivo glycated proteins: They are related to the pathological state of patients and have been invoked as responsible for tissue modifications. The digested mixtures obtained by the two enzymes were analyzed by MALDI/MS and LC/ESI/MSn, and clear cut differences were found. First of all, the digestion products of glycated HSA are generally less abundant than those observed in the case of unglycated HSA, accounting for the lower proclivity of the former to enzymatic digestion. MS/MS experiments on doubly charged ions, comparisons with a protein database, and molecular modeling to identify the lysine NH2 groups most exposed to glycation, identified some glycated peptides in digestion mixtures obtained from both types of enzymatic digestion. Residues 233K, 276K, 378K, 545K, and 525K seem to be privileged glycation sites, in agreement with the fractional solvent accessible surface values calculated by molecular modeling.  相似文献   
87.
Benzyl p-bromophenyl sulfoxide 1 was obtained on a multigram scale and in an enantiomerically pure form by an enantioselective catalytic oxidation, using tert-butyl hydroperoxide in the presence of chiral titanium complexes. Some mechanistic and stereochemical features of interest were studied in this process. Compound 1 was then subjected to two different substitution reactions with Grignard reagents, which caused two sequentially stereocontrolled carbon-for-carbon displacements, leading to chiral nonracemic dialkyl sulfoxides.  相似文献   
88.
89.
The theory of the experimental apparatus used for producing and revealing magnetomechanical waves, was elaborated. It was demonstrated that, in the investigated case, the measured amplitude of the elastomagnetic waves is a function of the reversible permeability as well as the elastic and piezomagnetic coefficients. All the last parameters are sensitive to both structure changes and magnetic interaction variations. Therefore during the heat treatment the magnetoelastic wave amplitude is a physical sensor with which we can investigate phase transitions. On this basis the effects of the structural relaxation, the ferro-paramagnetic state transition and the amorphous-crystalline structure development, were investigated in samples of metallic glass.  相似文献   
90.
The structural investigation of the products arising from 28 days incubation of albumin with high glucose concentration and further enzymatic hydrolysis has been carried out by means of high-performance liquid chromatography/mass spectrometry (HPLC/MS) under plasmaspray conditions. By this approach many different compounds have been detected, and for most of them, possible structures have been proposed on the basis of literature data and molecular weight assignments.  相似文献   
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