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1.
Considerable variations in the suppression of graft-versus-host disease with monoclonal anti-Thy-1 antibodies were found to relate to substantial differences noted in the expression of mouse Thy-1 marker on lymph node and spleen cells of Thy-1.1 (AKR/J, C57BL/6.Thy-1.1) and Thy 1.2 (AKR/Cu, C57BL/6) mice. Thy-1.1 mice showed a population of 22% (AKR/J) or 13% (C57BL/6-Thy-1.1) of Thy-1 negative cells among peripheral T cells carrying Ly-1 marker. This was in sharp contrast with Thy-1.2 mice, where as expected practically all peripheral T cells expressed both Thy-1 and Ly-1. Double-marker analysis on FACScan revealed that the Thy-1-/Ly-1+ cell population identified in Thy-1.1 but not in Thy-1.2 mice doubtless represents T cells because they express CD3 and either the L3T4 (CD4) or Lyt2 (CD8) phenotype. Using quantitative fluorescence-measurement techniques, it was found in addition that the Thy-1 antigen-binding sites on Thy-1+ cells from Thy-1.1 mice are considerably fewer than those present in Thy-1.2 mice. In fact, the Thy-1 antigen-binding sites approximate the level of Ly-1 density. Consequences of the reduced expression of Thy-1 became apparent in vivo: (1) lymphnode and splenic T cell areas in Thy-1.1 mice were clearly less depleted when Thy-1.1 and Thy-1.2 mice had been injected with rat IgG2b anti-Thy-1 mAb; and (2) GvHD was prevented completely in fully mismatched mice by anti-Thy-1 mAb if the donor mice expressed Thy-1.2 but was barely delayed if the donors expressed Thy-1.1. Thus the present study provides a transplantation model for comparing differences in T antigen density and their consequences for antibody-induced immunosuppression. 相似文献
2.
Markus Donix Bettina Beuthien-Baumann Rüdiger von Kummer Georg Gahn Fatima Thomas Vjera Holthoff 《Journal of clinical neuroscience》2007,14(6):601-603
Waldenstrom's macroglobulinemia (WM) is an uncommon low-grade lymphoma. Cognitive impairment due to central nervous system infiltration by lymphoplasmocytoid cells (Bing-Neel syndrome) has been rarely reported. We describe a 54-year-old man who was referred to a memory disorder clinic with a 9-month history of clinically obvious nonfluent aphasia and WM. He underwent extensive neuropsychological testing, clinical examination and structural and functional brain imaging. The diagnosis of the diffuse form of the Bing-Neel syndrome was supported by abnormal lymphoid cells found in the cerebrospinal fluid. Structural and functional brain imaging revealed impairment of brain areas due to white matter changes and subsequent functional deficits mimicking the neuropsychological syndrome encountered in progressive nonfluent aphasia. The diffuse form of Bing-Neel syndrome and neurological deficits are assumed to be the result of leptomeningeal infiltration by malignant cells and/or neoplastic vascular obstruction. 相似文献
3.
Birgit Herting MD Bettina Beuthien‐Baumann MD Katrin Pöttrich PhD Markus Donix MD Antje Triemer PhD Johannes B. Lampe MD Rüdiger von Kummer MD Karl Herholz MD Heinz Reichmann MD Vjera A. Holthoff MD 《Movement disorders》2007,22(4):490-497
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction. 相似文献
4.
This study was carried out to determine the ultrastructure and origin of previously described neurotensin-like immunoreactive (NT-LI) nerve fibres in the wall of the carotid sinus of the guinea pig. In our degeneration experiments, these NT-LI axons were unaffected by surgical sympathectomy but disappeared in response to transection of the carotid sinus nerve, thus suggesting a sensory origin. This assumption could be supported by combined retrograde tracing and immunohistochemistry. Primary afferent neurons of the sensory glossopharyngeal (petrosal) ganglion projecting to the carotid sinus were identified by injecting the retrograde fluorescent tracer, Fluoro-Gold, into the sinus wall, and some of these neurons displayed NT-LI. Within the carotid sinus, the terminals of these NT-LI sensory neurons exhibited ultrastructural features characteristic of baroreceptor endings, i.e. axonal swellings filled with mitochondria and closely associated to elastin. However, many endings also fulfilling the ultrastructural criteria for baroreceptors were devoid of immunolabelling. Thus, we conclude that the NT-LI terminals constitute a subgroup rather than the entire population of baroreceptor endings within the guinea pig carotid sinus. With respect to the established pharmacological effects of NT in guinea pig, we propose an involvement of NT-LI fibres in the modulation of baroreception at the peripheral level. 相似文献
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7.
The stability of the basic unit for fixation of the Ilizarov external fixation system was tested in several loading modes. The effects of varying the number of wires and the orientation of wire placement were studied. The fixation units were mounted on a plastic, simulated, long bone and tested by loading in several directions. The Ilizarov fixation ring was found to be relatively stiff in axial compression and torsion. Its stiffness in this mode was directly proportional to the number of wires in the system and independent of the configuration of wire placement. Loading in bending and in shear provided much lower levels of stiffness, and this was dependent on the angles formed between the wires. The addition of a wire at a minimum distance of 4 cm from the primary ring significantly improved bending stiffness. The use of opposed olive wires also improved shear stiffness. 相似文献
8.
In an open, non-randomized 3-way cross-over study, the bioavailability of 2-oxo-pyrrolidine-1-acetamide (piracetam, Encetrop) from two solid oral formulations and one liquid formulation was tested in 8 healthy male volunteers. The area under the concentration time curve, which is defined to be a measurement for bioequivalence among the three tested galenic formulations correlated very well with the area under the effect intensity-time curve, which was estimated in the same volunteers using electro-physiological methods. The different methods of estimation of bioequivalence show similarity between both solid galenic formulations, while the liquid form exhibits superiority in respect to the oral solid formulations. 相似文献
9.
Summary. The ACL in the rabbit is innervated by three types of nerve fibres. These subserve vasoconstriction, nociceptive and proprioceptive
purposes. The aim of this paper was to investigate the revascularisation and reinnervation of cyropreserved ACL allografts
in 22 New Zealand white rabbits. Cyropreserved grafts were used as they may excite less host immune response. Both microangiographic
and immunohistochemical methods were used. We found that cryopreserved allografts exhibited little immune response, revascularisation
was considerable by the 24th postoperative week and reinnervation was essentially complete by then. No mechanoreceptors were
found in ACL allografts. In rabbits, the anatomical basis for the participation of ACL allografts in sensorimotor reflexes
is not given before the twelfth week after transplantation.
Accepted: 11 May 1995 相似文献
Résumé. Nous avons examiné par méthodes micro-angiographiques et immuno-histo-chimiques la revascularisation et l’innervation d’un allogreffon cryopréservé (os – ligament croisé antérieur – os), chez 22 lapins de Nouvelle Zélande. Au sein de la greffe, existe une hypervascularisation maximale à 6 semaines, persistante à 12 semaines et se normalisant 24 semaines après la transplantation. Le panicule adipeux du genou était une source importante pour la revascularisation du greffon. L’immuno-histo-chimie a montré la présence de 3 types de fibres nerveuses au sein du ligament croisé: des afférents sensoriels mécano-réceptifs, des afférents sensoriels nociceptifs et des efférents sympathiques vaso-moteurs. Les contr?les ont montré l’existence de plusieurs fibres des 3 types de nerf; les terminaisons sensitives étaient toutes des corpuscules de Ruffini. Il n’y avait pas de fibre nerveuse au sein de l’allogreffe du ligament croiséà 3 et 6 semaines après la transplantation. Des fibres d’aspect cicatriciel étaient détectées à 12 semaines, tandis que des contr?les plus tardifs montraient un nombre et une distribution presque normale des filets nerveux. Aucun récepteur mécanique ne fut trouvé dans l’allogreffe. Chez le lapin, les bases anatomiques de la participation sensitivo-motrice de l’allogreffe du ligament croisé antérieur n’existent pas avant la 12ème semaine après la transplantation.
Accepted: 11 May 1995 相似文献
10.
胫骨外侧髁骨折塌陷对关节轴线及接触压力的影响 总被引:1,自引:0,他引:1
目的:研究在胫骨外侧髁骨折中关节面塌陷和外侧半月板切除对膝关节轴线、接触面积及压力的影响。方法:6个新鲜尸体膝关节标本制成胫骨外侧髁劈裂骨折模型,通过使用支撑垫片制成关节面塌陷0、1、2、4和6mm。膝关节在屈膝0°,负荷500N和屈膝30°,负荷350N。通过数码相机记录关节轴线的变化;而关节内外间隙的压力和压力扩散则由F-Scan感应器记录。每个标本在保留和切除外侧半月板下进行测试。结果:随着关节面塌陷高度的增加,膝关节外翻角度、外侧间隙的平均和最大的接触压力逐渐增加,而接触面积则逐渐减少。在屈膝0°,关节面塌陷6mm时,外翻角度平均增加7.6°,平均接触压力和最大接触压力分别增加208%和97%;而接触面积则减少33%。在同一关节面塌陷高度,切除半月板平均增加38%的外翻角度和外侧间隙45%的接触压力;而接触面积则减少26%。结论:研究结果表明在治疗胫骨外髁劈裂骨折中,减少关节面的塌陷十分重要,特别是在需切除半月板的时候。 相似文献