| 1. |
- Belichenko, P, et al.
(author)
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Dendritic morphology in epileptogenic cortex from TRPE patients, revealed by intracellular Lucifer Yellow microinjection and confocal laser scanning microscopy.
- 1994
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In: Epilepsy research. - 0920-1211. ; 18:3, s. 233-47
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Journal article (peer-reviewed)abstract
- Biopsy material was obtained from cortical epileptogenic zones (eight temporal, one occipital, one parietal and one frontal) of eleven patients aged 1.5-47 years with therapy-resistant partial epilepsy (TRPE) undergoing epilepsy surgery. Control autopsy material (two temporal, two occipital, one parietal and one frontal) was removed from six neurologically healthy cases within 6-10 hours postmortem delay. In each specimen, 100-300 pyramidal and non-pyramidal neurons were visualized by intracellular Lucifer Yellow microinjection. Single neurons were imaged using CLSM generated serial optical sections; 2-D reconstruction of each neuron was made using z-projection of serial optical images, and 3-D reconstructions and rotations were computerized. Neuronal maps from TRPE biopsies, compared to control autopsies, show markedly increased numbers of dendritic abnormalities of single pyramidal and non-pyramidal neurons in layers I, II-III, V-VII, and in the subcortical white matter. The abnormalities include: (1) increased number of non-pyramidal cells in layer I; (2) many pyramidal cells with two or three dendrites originating apically, rather than one single apical dendrite, in layers II-III; (3) atypical orientation of oblique apical and basal dendrites in pyramidal neurons of layers II-VII; (4) increased number of atypical 'dinosaur-like' and fusiform cells in layers V-VII; (5) numerous neurons in the white matter. These abnormalities may be etiological in cases with early onset, and predisposing in cases with late onset.
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| 2. |
- Chen, W., et al.
(author)
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Electronic and geometric structure of clean Pt3Ti(111)
- 1994
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In: Physical Review B. - 0163-1829 .- 1095-3795. ; 50:8, s. 5620-5627
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Journal article (peer-reviewed)abstract
- Photoemission spectra and scanning tunneling microscopy (STM) images of the clean Pt3Ti(111) surface are presented. Grazing-emission core-level spectra show that the topmost layer is pure platinum, modified compared with the Pt(111) surface. The Pt 4f levels at the surface are shifted 0.4 eV toward the Fermi level relative to bulk Pt3Ti while the Pt 4f and Ti 2p levels in the bulk are shifted 0.4 and 1.3 eV to higher binding energy relative to pure bulk platinum and titanium, respectively, Tunneling measurements show a surface with only metallic atoms and a small p(2×2) buckling. Our observations of molecularly adsorbed CO are not compatible with metallic titanium atoms at the surface and the STM data thus indirectly confirm that only platinum atoms are present in the topmost layer. Linear muffin-tin-orbital calculations of the bulk band structure and valence-band photoemission spectra reveal highly hybridized electron states between the Pt d and Ti d levels. The calculations give a minor charge transfer from Ti to Pt, 0.37 electrons per Ti atom, but the large core-level shifts reflect the stability of the alloy and the response to the excitation rather than the amount of charge transfer. The observed segregation of platinum to the surface and the altered electronic structure of the topmost layer, due to interaction with the underlying alloy, are in full agreement with earlier conclusions based on low-energy electron-diffraction measurements and on the chemical properties of the surface. © 1994 The American Physical Society.
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| 3. |
- Chen, W., et al.
(author)
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Structure determination of Pt3Ti(111) by automated tensor LEED
- 1993
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In: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 5, s. 4585-4594
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Journal article (peer-reviewed)abstract
- An analysis of low-energy electron diffraction (LEED) I-V spectra from the clean Pt3Ti(111) surface was performed by comparing measured intensities with data calculated using an automated tensor LEED program, which employs a directed search optimization procedure. It was found that the topmost layer is pure Pt and that the other layers have the bulk composition. The first and second interlayer spacings are 2.23+or-0.03 AA and 2.21+or-0.03 AA respectively, corresponding to a contraction of 0.9% and 1.8% of the bulk value. The perpendicular buckling is 0.04 AA +or-0.05 AA in the top layer and 0.15 AA +or-0.04 AA in the second layer. The results are in full accordance with previous investigations of the physical and chemical properties of this surface.
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| 4. |
- McLoughlin, Paul, et al.
(author)
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Lung pathology in HIV positive patients
- 1990
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In: Irish Medical Journal. - Dublin : Irish Medical Association. - 0332-3102. ; 83:3, s. 109-111
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Journal article (peer-reviewed)abstract
- We describe the results of 43 bronchoscopic examinations carried out on 35 patients who were HIV positive. Of these, 13 were intravenous drug abusers, 13 were homosexual or bisexual, six were haemophiliacs, two were homosexual intravenous drug abusers and one was a heteroexual contact of a drug abuser. All underwent investigation because of respiratory symptoms. Aetiological diagnosis could not be made from physical examination, x-ray or routine laboratory tests but, was usually made using bronchoscopy and its associated investigations. Using these techniques, Pneumocystis carinii pneumonia was the commonest diagnosis (19 cases) followed by bacterial infection. Mycobacterial infection accounted for two cases and non-specific interstitial pneumonitis accounted for three. Kaposi's sarcoma was found in one instance and eight investigations were non-diagnostic.
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