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141.
Krimer LS; Hyde TM; Herman MM; Saunders RC 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(8):722-731
The entorhinal cortex (ERC) has been implicated in the pathophysiology of
Alzheimer's disease, schizophrenia and other disorders affecting cognitive
functions. While powerful anatomical and histochemical methods
(immunohistochemistry, in situ hybridization, etc.) may be applied
(although with limitations) to postmortem human brain, each analysis should
utilize a cytoarchitectonic approach to provide appropriate comparisons
within the subdivisions of the ERC. Accordingly, we describe here the
normal cyto- and myeloarchitecture of the human ERC as a prerequisite for
the accompanying study of this region in schizophrenia. Our parcellation of
this cortex differs from previous treatments in three ways. First, we
adopted specific criteria of inclusion to define each subdivision of the
region. Although distinctive ERC features are most prominent in the
intermediate portion of this region, at least one of these features was
considered the minimum necessary criterion to include adjacent tissue in
the entorhinal area. Second, we used morphometric measurements (neuronal
size and density as well as subdivisional volume and laminar thickness) to
support our qualitative evaluation. Third, we have applied to the human ERC
the conventional cytoarchitectonic nomenclature of the entorhinal cortex
used previously in studies of non-human primates. This allows a more
accurate extrapolation of the available numerous experimental anatomical,
physiological and psychological data on this region to the human. As in the
monkey, the five main subareas were recognized in the human (prorhinal,
lateral, intermediate, sulcal and medial) but three required further
subdivision (intermediate, sulcal and medial). The morphometric results
obtained suggested a progression of the human entorhinal cortex from the
peripheral to the central subareas, with the intermediate subarea (281) as
the most complete entorhinal subdivision. Compared with non-human primates,
the human ERC not only retains the basic periallocortical organization but
also demonstrates further evolution. Taken together with available
experimental data on the connectivity of this brain region, these results
provide an anatomical basis for evaluating the ERC in human behavior.
相似文献
142.
Hepatic tumors: comparison of CT during arterial portography, delayed CT, and MR imaging for preoperative evaluation 总被引:6,自引:0,他引:6
Forty-three patients with known primary or secondary neoplastic involvement of the liver underwent evaluation to determine the number, size, and location of focal lesions before possible tumor resection. Imaging studies included computed tomography (CT) during arterial portography (CTAP), delayed CT, and magnetic resonance (MR) imaging at various pulse sequences. Results of radiologic studies were compared with surgical and pathologic findings. In the combined group of surgical and nonsurgical patients, CTAP was significantly more sensitive (85%) than all other techniques except 1.5-T T2-weighted spin-echo imaging (64%). Combining the information from all MR pulse sequences yielded a cumulative sensitivity of 68%. Combining the information from two modalities yielded sensitivity of 96% for CTAP plus MR imaging, 85% for CTAP plus delayed CT, and 77% for delayed CT plus MR imaging. The authors conclude that when it is vital to know the precise number, size, and location of focal hepatic lesions before tumor resection, CTAP has the highest sensitivity, but MR imaging is an important adjuvant. 相似文献
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Anterior temporal lobes and hippocampal formations: normative volumetric measurements from MR images in young adults 总被引:25,自引:0,他引:25
Jack CR Jr; Twomey CK; Zinsmeister AR; Sharbrough FW; Petersen RC; Cascino GD 《Radiology》1989,172(2):549-554
Volumes of the right and left anterior temporal lobes and hippocampal formations were measured from magnetic resonance images in 52 healthy volunteers, aged 20-40 years. Subjects were selected by age, sex, and handedness to evaluate possible effect of these variables. Data were normalized for variation in total intracranial volume between individuals. Right-left asymmetry in the volumes of the anterior temporal lobes and hippocampal formations was a normal finding. The anterior temporal lobe of the non-dominant (right) hemisphere was larger than the left by a small (mean right-left difference, 2.3 cm3) but statistically significant amount (P less than .005) in right-handed subjects. No significant effect of age or sex was seen in normalized right or left anterior temporal lobe volume. The right hippocampal formation was larger than the left for all subjects by a small (mean right-left difference, 0.3 cm3) but statistically significant amount (P less than .001). No effect of age, sex, or handedness was seen in normalized hippocampal formation volumes. 相似文献
146.
A family showing inheritance of the Inab phenotype 总被引:2,自引:0,他引:2
An 86-year-old white American woman was found to have a very rare red cell phenotype, the Inab phenotype. Her cells were Cr(a-), Tc(a-b-c-), Dr(a-), Es(a-), WES(a-b-), and IFC-. Unlike the two other Inab phenotype patients, she has no history of protein-losing enteropathy or any similar intestinal disorder. One of her four siblings also has the Inab phenotype, providing the first evidence that this phenotype may be inherited. Serum inhibitions showed that anit-Cra, -TCa, -Dra, -WESb, and -IFC are partially inhibited by sera from three siblings with the common red cell phenotype but not by serum from the Inab phenotype sibling. The serum of the proposita contained an antibody to a high-frequency antigen that showed characteristics of being a Cromer-related antibody. 相似文献
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