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We have developed an on-line archive of neuronal geometry to encourage the use of realistic dendritic structures in morphometry and for neuronal modeling, located at web address www.neuro.soton.ac.uk. Initially we have included full three-dimensional representations of 87 neurons from the hippocampus, obtained following intracellular staining with biocytin and reconstruction using Neurolucida. The archive system includes a structure editor for correcting any departures from valid branching geometry and which allows simple errors in the digitisation to be corrected. The editor employs a platform-independent file format which enforces the constraints that there should be no isolated branches and no closed loops. It also incorporates software for interconversion between the archive format and those used by various neuronal reconstruction and modelling packages. The raw data from digitisation software can be included in the archive as well as edited reconstructions and any further information available. Cross-referenced tables and indexes are updated automatically and are sorted according to a number of fields including the cell type, contributor, submission date and published reference. Both the archive and the structure editor should facilitate the quantitative use of full three-dimensional reconstructions of neurons from the hippocampus and other brain regions.  相似文献   
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Children's Fright Reactions to Television News   总被引:1,自引:0,他引:1  
In a random survey of parents of kindergarten, second, fourth, and sixth grade children, 37% of the children were reported to have been frightened or upset by a news story on television. The percentage of children being frightened by news increased from kindergarten to the elementary school years, whereas the tendency to be frightened by fantastic, unreal content showed a decreasing trend. The top categories of stories producing fear were violence between strangers, foreign wars and famines, and natural disasters. me tendency to respond with fright to violence between strangers increased with age, and the tendency to be upset by natural disasters decreased with age. Proposed explanations for the observed age differences were based on developmental differences in children's understanding of the fantasy-reality distinction and in their responsiveness to perceptually salient stimuli.  相似文献   
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46 patients with coronary heart disease with hypercholesterolemia were exposed to therapeutic plasmapheresis (TP) in combination with alpha-tocopherol treatment (AT). The results of 3-month follow-up with assessment of the clinical status, lipid spectrum, lipid peroxidation, concentration of ceruloplasmin indicated high hypolipidemic effectiveness of TP 2-3 weeks after the treatment as shown by inhibition of lipid peroxidation and antioxidant system. The addition of AT prolonged the hypolipidemic effect of TP, promoted optimization of plasma antioxidant potential (a rise in HDL, stabilization of ceruloplasmin levels).  相似文献   
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Antibodies that neutralize primary isolates of human immunodeficiency virus type 1 (HIV-1) appear during HIV-1 infection but are difficult to elicit by immunization with current vaccine products comprised of monomeric forms of HIV-1 envelope glycoprotein gp120. The limited neutralizing antibody response generated by gp120 vaccine products could be due to the absence or inaccessibility of the relevant epitopes. To determine whether neutralizing antibodies from HIV-1-infected patients bind to epitopes accessible on monomeric gp120 and/or oligomeric gp140 (ogp140), purified total immunoglobulin from the sera of two HIV-1-infected patients as well as pooled HIV immune globulin were selectively depleted of antibodies which bound to immobilized gp120 or ogp140. After passage of each immunoglobulin preparation through the respective columns, antibody titers against gp120 and ogp140 were specifically reduced at least 128-fold. The gp120- and gp140-depleted antibody fraction from each serum displayed reduced neutralization activity against three primary and two T-cell line-adapted (TCLA) HIV-1 isolates. Significant residual neutralizing activity, however, persisted in the depleted sera, indicating additional neutralizing antibody specificities. gp120- and ogp140-specific antibodies eluted from each column neutralized both primary and TCLA viruses. These data demonstrate the presence and accessibility of epitopes on both monomeric gp120 and ogp140 that are specific for antibodies that are capable of neutralizing primary isolates of HIV-1. Thus, the difficulties associated with eliciting neutralizing antibodies by using current monomeric gp120 subunit vaccines may be related less to improper protein structure and more to ineffective immunogen formulation and/or presentation.  相似文献   
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