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111.
Krimer LS; Herman MM; Saunders RC; Boyd JC; Hyde TM; Carter JM; Kleinman JE; Weinberger DR 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(8):732-739
The entorhinal cortex (ERC) has been implicated in schizophrenia by a
number of studies. There is anatomical observation of neuronal heterotopias
in the rostral ERC, which is consistent with a hypothesis of
neurodevelopmental abnormalities in this disease. In view of the
significant cytoarchitectonic variation of the ERC throughout its
rostro-caudal extent, we performed a detailed subareal analysis of the
rostral two-thirds of the entorhinal cortex (ERCr) in 14 postmortem
schizophrenic brains and 14 matched controls (mean ages of 48 and 47
respectively). This systematic evaluation included both a qualitative
microscopic analysis of morphogenetic anomalies that would be consistent
with neurodevelopmental pathology and quantitative measurements of total
neuronal number, average neuronal density, laminar volume and laminar depth
from the cortical surface in cytoarchitectonically matched subareas of
schizophrenic and control brains. Parcellation of the entire ERC on the
basis of cytoarchitectonic criteria identified five distinct regions,
similar to those described in the macaque, except that in the human brain
three of the regions were further divisible into two or three subareas,
yielding nine distinct cellular compartments. Five rostral areas, prorhinal
(Pr), lateral (28L), intermediate rostral and caudal (281r and 281c), and
sulcal (28S), comprise the ERCr. Gross and microscopic examination of these
subdivisions throughout the ERCr failed to reveal laminar disorganization
in any of the schizophrenic brains. The brains also did not differ
significantly with respect to total neuronal number, total volume and
neuronal density per laminar and subareal subdivision, or laminar thickness
per entorhinal subarea. However, neuronal number and density were reduced
by 12-18% in Pr and 28L, suggesting that mild quantitative abnormalities
may exist in the ERCr and might possibly be revealed in a larger sample of
schizophrenic brains. We have failed to confirm previous reports of laminar
disorganization in the ERCr in brains of patients with schizophrenia; to
the extent that this region is implicated in schizophrenia, the structural
changes are likely to consist of more subtle cellular disturbances.
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S Le P Langlois RC Vytialingam NA Aziz 《Journal of Medical Imaging and Radiation Oncology》1999,43(2):201-205
With increasing budgetary restraints on the health system, it is apparent that the main contribution that radiology departments can make to significant cost reduction in hospitals is to decrease the length of time between requesting an X-ray examination and receiving the report (and images). Digital radiography (DR) was introduced into the Radiology Department at the Royal Adelaide Hospital as a pilot project to research the cost–benefits and efficiency of the system, and to determine future directions for planning a digital department. The business plan developed prior to implementation of this pilot project predicted a saving of one bed-day per inpatient when a fully digital department with a picture archiving and communication system (PACS) is installed. This initial study comparing DR and conventional radiography (convR) provides baseline data and shows encouraging results for more rapid transmission of reports to clinicians. 相似文献
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J.W. Oldham L.E. Allred G.E. Milo O. Kindig C.C. Capen 《Toxicology and applied pharmacology》1980,52(1):159-168
Normal human fibroblasts in vitro were used as a system to examine the cellular effects of potentially toxic compounds. In addition to tests for viability, indices of toxicity were included which would demonstrate functional and structural alterations associated with specific subcellular components. Fibroblast cultures derived from human neonatal foreskin were treated with various doses of the mycotoxins T-2 and T-2 tetraol. Methods for demonstrating viability showed T-2 to be 10-fold more toxic than its hydroxylated derivative, T-2 tetraol. Both compounds induced a dose-dependent reduction in protein and scheduled DNA synthesis, as well as an induction of unscheduled DNA synthesis (DNA repair). However, no qualitative alterations in the activity of cytoplasmic, lysosomal or membrane-associated enzymes were observed with T-2 or T-2 tetraol-treated cells. Transmission electron microscopy revealed structural alterations predominantly associated with the nucleus and the endoplasmic reticulum with associated ribosomes. Multiple biochemical parameters with ultrastructural and cytotoxicity studies were therefore effective in demonstrating the mechanisms as well as the degree of toxicity induced by these chemical compounds. 相似文献
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