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61.
At the early onset of the 20th century, several studies already reported that the gray matter was implicated in the histopathology of multiple sclerosis
(MS). However, as white matter pathology long received predominant attention in this disease, and histological staining techniques
for detecting myelin in the gray matter were suboptimal, it was not until the beginning of the 21st century that the true extent and importance of gray matter pathology in MS was finally recognized. Gray matter damage was
shown to be frequent and extensive, and more pronounced in the progressive disease phases. Several studies subsequently demonstrated
that the histopathology of gray matter lesions differs from that of white matter lesions. Unfortunately, imaging of pathology
in gray matter structures proved to be difficult, especially when using conventional magnetic resonance imaging (MRI) techniques.
However, with the recent introduction of several more advanced MRI techniques, the detection of cortical and subcortical damage
in MS has considerably improved. This has important consequences for studying the clinical correlates of gray matter damage.
In this review, we provide an overview of what has been learned about imaging of gray matter damage in MS, and offer a brief
perspective with regards to future developments in this field. 相似文献
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On the origins of esterases 总被引:8,自引:0,他引:8
Comparisons among the primary sequences of five cloned eukaryotic esterases
reveal two distinct lineages, neither bearing any significant overall
sequence similarity to the functionally related serine protease multigene
family. We have not eliminated the possibility that the esterases may have
residual conformational similarities to the serine proteases. However, our
profile analysis and analyses of the predicted conformations of the
esterases reveal little similarity to the serine proteases. Four of the
esterase proteins share 27%-53% overall sequence similarity and evidence of
a catalytic mechanism involving the same Arg- Asp-Ser or His-Asp-Ser charge
relay. We propose that these four esterases, three of them cholinesterases,
form part of a multigene family essentially separate from the serine
proteases.
相似文献
65.
Nicholas JG Webster Lui-Guojing Evans Matt Caples Laura Erker Shern L Chew 《BMC molecular biology》2004,5(1):7-15
Background
Incorporation of exon 11 of the insulin receptor gene is both developmentally and hormonally-regulated. Previously, we have shown the presence of enhancer and silencer elements that modulate the incorporation of the small 36-nucleotide exon. In this study, we investigated the role of inherent splice site strength in the alternative splicing decision and whether recognition of the splice sites is the major determinant of exon incorporation. 相似文献66.
67.
Using zonal sucrose density gradient centrifugation methods to fractionate the subcellular components in gastric mucosal homogenates have been developed. Methods are described which give high yield or rapidity in fractionation. A procedure is described which enables large-scale preparations of smooth walled vesicular membranes containing HCO3?-ATPase activity free from mitochondrial contamination as assessed by electron microscopic morphology and undetectable succinic dehydrogenase or monoamine oxidase activity. A method to purify gastric mitochondria is also described. 相似文献