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991.
992.
Summary Degeneration of heterogeneous systems in the central nervous system, with widespread distribution of argyrophilic neuronal fibrillary inclusions, was found in a patient with presenile dementia. Atrophy was circumscribed in the frontal and temporal lobes. Neuronal loss was severe in the basal ganglia, subthalamic nucleus, and substantia nigra. Immunocytochemical study using anti-phosphorylated tau and anti-ubiquitin antibodies in conjunction with ultrastructural observations revealed two types of inclusions: neurofibrillary tangles (NFTs) of progressive supranuclear palsy (PSP) in the Edinger-Westphal nucleus, locus coeruleus, cerebellar dentate nucleus, inferior olivary nucleus, and posterior horn of the spinal cord; and Pick bodies (PBs) in the atrophied cerebral cortex and red nucleus. PSP-type NFTs and PBs have been demonstrated in a single case for the first time. Despite their pathognomonic significance in certain disorders, we suggest that these inclusions may reflect a form of cytoskeletal disorganization, which is not entirely restricted to a single disease entity. 相似文献
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994.
995.
The spinal reflex potentials elicited by electrical stimulation of the tibial nerve were recorded from the lumbo-sacral ventral root in spinal cats. When the thoracic aorta and the bilateral internal mammary arteries were occluded for 10 min, the potentials were completely depressed. Reappearance of these potentials could be observed at about 10 min after removal of the occlusion and they gradually recovered. Intravenous injection of naloxone (1 or 10 mg/kg) or levallorphan (0.1 mg/kg) together with removal of occlusion significantly promoted the recovery of the polysynaptic reflex potential. Morphine (5 mg/kg) showed no particular effect on the recovery of potentials. Furthermore, pretreatment with morphine (5 mg/kg) did not influence the effects of these opioid antagonists. These results suggest that naloxone and levallorphan may preserve or potentiate the interneuronal activities of the lumbo-sacral spinal cord under the ischemic condition and that the effects may not be mediated through morphine-like opioid receptors. 相似文献
996.
Observation of the ocular fundus by an infrared-sensitive video camera after vitreoretinal surgery assisted by indocyanine green. 总被引:1,自引:0,他引:1
Shigeki Machida Takamitsu Fujiwara Toshihiro Gotoh Yutaka Hasegawa Akiko Gotoh Yutaka Tazawa 《Retina (Philadelphia, Pa.)》2003,23(2):183-191
PURPOSE: To investigate how long indocyanine green (ICG) dye remains in the ocular fundus and how the remaining dye interferes with ICG angiographic findings after vitreoretinal surgery assisted by ICG. METHODS: Eight eyes with macular hole, three with epiretinal membrane, and one with an intraocular foreign body were included. Those patients underwent vitrectomy facilitated by an intraocular administration of ICG. An infrared sensitive video camera was used to take fundus pictures pre- and postoperatively. In 2 of 12 cases, the authors performed ICG angiography at 2 weeks and at 3 months after the surgery. RESULTS: At 1 month after surgery, diffuse hyperfluorescence was observed throughout the posterior pole of the ocular fundus in all cases. The area where macular hole existed before the surgeries revealed hyperfluorescence in 6 of 8 eyes with macular hole (75%). These hyperfluorescent findings became less prominent with time postoperatively, while optic disk hyperfluorescence persisted for 12 months in all cases. In the early phase of ICG angiography at 2 weeks postoperatively, the retinal and choroidal circulation could be depicted. However, in the middle phase the choroidal veins were hardly visible. The angiographic pictures of the late phase mimicked those seen without intravascular administration of ICG. Even at 3 months after surgery, the optic nerve head revealed hyperfluorescence in the middle and late phases. CONCLUSIONS: The residual ICG in the ocular fundus produced prolonged hyperfluorescence after surgery. This abnormal condition affected ICG angiographic findings in the middle and late phases. 相似文献
997.
998.
An artificial amino acid, 4-iodo-L-meta-tyrosine: biodistribution and excretion via kidney. 总被引:1,自引:0,他引:1
Naoto Shikano Keiichi Kawai Leo Garcia Flores Ryuichi Nishii Nobuo Kubota Nobuyoshi Ishikawa Akiko Kubodera 《Journal of nuclear medicine》2003,44(4):625-631
We evaluated the use of radiolabeled 4-iodo-L-meta-tyrosine as an amino acid transport marker. The pharmacologic features of this compound, particularly the biodistribution and excretion, were examined by conducting in vivo and in vitro studies using 4-(125)I-iodo-L-meta-tyrosine (4-(125)I-mTyr). Results obtained for L-(14)C-Tyr and 3-(125)I-iodo-alpha-methyl-L-tyrosine ((125)I-IMT) were used for comparison. METHODS: In vivo biodistribution studies of 4-(125)I-mTyr were performed in male ddY mice. Urinary excretion of 4-(125)I-mTyr and (125)I-IMT with administration of probenecid was studied. Local distribution of 4-(125)I-mTyr and (125)I-IMT in kidney was visualized by autoradiography. We performed metabolite analysis of 4-(125)I-mTyr in mice. For in vitro studies, reabsorption mechanisms of 4-(125)I-mTyr were compared with those of (125)I-IMT and the parent L-(14)C-Tyr using superconfluent monolayers of the porcine kidney epithelial cell line LLC-PK(1) in medium containing inhibitor (L-Tyr, D-Tyr, and 2,4-dinitrophenol), in Na(+)-free medium, and at 4 degrees C. RESULTS: 4-(125)I-mTyr demonstrated high accumulation in the pancreas and kidney and comparable brain uptake to that of (125)I-IMT. Blood clearance of 4-(125)I-mTyr was faster than that of (125)I-IMT. Three hours after administration, >70% of 4-(125)I-mTyr was excreted via the urine, whereas <5% was found in the feces. Renal autoradiography revealed moderate accumulation of 4-(125)I-mTyr and high accumulation of (125)I-IMT in the renal cortex. Probenecid further reduced accumulation of 4-(125)I-mTyr and (125)I-IMT in the kidney as well as urinary excretion. At 30 min after tracer injection, intact free 4-(125)I-mTyr accounted for >98.1% of the total present in kidney and >96.3% in urine. Protein incorporation was not observed. Uptake of 4-(125)I-mTyr into LLC-PK(1) cell monolayers was remarkably reduced by 5 mmol/L L-Tyr (4.6%) and incubation at 4 degrees C (15.6%) but was reduced by 5 mmol/L D-Tyr (50.0%). L-(14)C-Tyr and (125)I-IMT showed similar results; however, uptake of (125)I-IMT was enhanced by 0.1 mmol/L 2,4-dinitrophenol (165.1%), an inhibitor of generation of energy-rich phosphates. CONCLUSION: The artificial amino acid 4-(125)I-mTyr demonstrated high metabolic stability, rapid blood clearance, rapid urinary excretion, and similar biodistribution to other radiolabeled L-Tyr analogs. 4-(125)I-mTyr can be a competitive substrate of L-Tyr reabsorption. However, 4-(125)I-mTyr demonstrates different pharmacologic features than those of (125)I-IMT, particularly in renal handling. 4-(125)I-mTyr may potentially be applied as a new amino acid transport marker. 相似文献
999.
We report our rehabilitation experience for two patients with Churg-Strauss syndrome (CSS). To improve their functional prognoses, we started rehabilitation program compensating for their activity of daily livings from their early stage. Also, we paid special attention to prescribed drug effect and adverse effect. Since patients with the mononeuritis multiplex have restricted weakness in the muscles ruled by a specific nerve, rehabilitation approaches including orthoses should start to improve the compensatory ability of normal adjacent muscles even in their early stages. In addition, since functional improvement may be gradual and take some years from onset, we should start rehabilitation in their early stage to improve their functional prognoses. 相似文献
1000.
Yi Wang Ichiro Fujita Hiroshi Tamura Yusuke Murayama 《Cerebral cortex (New York, N.Y. : 1991)》2002,12(1):62-74
Receptive field (RF) structures of neurons in area TE of the monkey inferior temporal cortex were investigated under blockade of inhibition mediated by gamma-aminobutyric acid (GABA). Bicuculline methiodide, a GABA(A) receptor antagonist, was microiontophoretically administered to TE neurons. Blockade of inhibition enhanced responses to a particular range of visual stimuli not only at the RF center, but also at the periphery of or outside RFs where the stimuli originally evoked little or no response, enlarging the RFs. The strongest responses under normal and uninhibited conditions occurred at the RF center in most neurons. The largest increase in responses, reflecting the strongest inhibitory input, usually occurred at the RF center, but in some neurons it occurred in the periphery. A neuron had a silent region within its RF where some stimuli effective at adjacent locations could not elicit responses even under blockade of inhibition. We suggest that (i) afferent information to individual TE neurons originates from a wide retinotopic region beyond their normal RF; (ii) the afferent convergence is not necessarily complete throughout a RF; and (iii) GABAergic inhibition contributes to the generation of RF structures of TE neurons. 相似文献