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1.
We report two patients with severe hypoglycorrhachia after a subarachnoid hemorrhage. They had no obvious meningeal infection, and they spontaneously recovered within a few weeks. Such cases have previously been reported in neonates, but exceptionally in adults. Contrary to detailed cases from the literature, our patients recovered without antibiotics, and hypoglycorrhachia was very severe.  相似文献   
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Chronic thalamic-VIM stimulation was performed in 9 parkinsonian patients with disabling tremor and poor response to drugs. Neuropsychological assessment was performed before and after deep brain electrode implantation and stimulation. Mild cognitive disorders were observed prior to thalamic implantation. Neuropsychological testing failed to show intellectual function worsening after implantation and stimulation. We conclude that thalamic stimulation could be an appropriate treatment of untractable tremor as this could provide less neuropsychological side-effects than thalamotomy, especially in Parkinson's disease.  相似文献   
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Summary: The most common human viruses have different abilities to establish persistent chronic infection. Virus‐specific T‐cell responses are critical in the control of virus replication and in the prevention of disease in chronic infection. A large number of phenotypic markers and a series of functions have been used to characterize virus‐specific CD4+ and CD8+ T‐cell responses, and these studies have shown great phenotypic and functional heterogeneity of the T‐cell responses against different viruses. The heterogeneity of the T‐cell response has been proposed to be specific to each virus. However, over the past 2 years, several studies have provided evidence that the phenotypic and functional heterogeneity of CD4+ and CD8+ T‐cell responses is predominantly regulated by the levels of antigen load. The levels of antigen load modulate the phenotypic and functional patterns of the T‐cell response within the same virus infection. Furthermore, the functional characterization of virus‐specific CD4+ and CD8+ T‐cell responses has identified signatures of protective antiviral immunity. Polyfunctional, i.e. interleukin‐2 and interferon‐γ (IFN‐γ) secretion and proliferation, and not monofunctional, i.e. IFN‐γ secretion, CD4+ and CD8+ T‐cell responses represent correlates of protective antiviral immunity in chronic virus infections.  相似文献   
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Progressive multifocal leukoencephalopathy (PML) occurs in patients with profound immunosuppression. Although lesions are usually devoid of lymphoplasmocytic infiltrates, inflammatory forms of PML have been described, in both human immunodeficiency virus (HIV)-seropositive (HIV+) and-seronegative (HIV?) patients. In addition, PML has been shown to develop in HIV+ patients shortly after introduction of highly active antiretroviral therapy (HAART), despite a recovery of the immune system. Therefore, one could postulate that PML might arise in the context of an immune reconstitution syndrome. To examine the clinical and neuroradiological characteristics of inflammatory forms of PML, the authors performed a retrospective analysis of the patients seen at their institution since 1996 as well as a review of the literature. Of 39 HIV+ and HIV?PML patients, 5 (13%) presented with an inflammatory form of this disease. Two HIV+ patients developed PML soon after the onset of HAART, concomitant to immune recovery, as demonstrated by a decrease of HIV viral load (VL) and an increase of CD4+ T-cell count. Three patients (2 HIV+ and 1 HIV?) had signs of inflammation in the central nervous system (CNS) characterized by contrast-enhancing lesions on neuroimaging studies, and/or inflammatory infiltrates on brain biopsy. The presence of JC virus-specific cytotoxic T lymphocytes was demonstrated in 4/4 patients tested and the outcome was favorable in 3 of them. In agreement with previously published case reports, the data indicate that inflammatory reactions in PML are not infrequent, and that they are generally associated with a favorable prognosis. Therefore clinicians should not disregard the diagnosis of PML in presence of contrast-enhancing brain lesions, and should use caution before treating these immunosuppressed individuals with steroids.  相似文献   
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Tadpole and adult Xenopus, manipulated to be of comparable size, exhibited stagespecific antibody expression. The production of adult-type higher-affinity anti-DNP antibodies proved to be independent of the age and size of the individual and is concomitant with the completion of metamorphosis. The appearance of new antibody specificities at such a time suggests that their expression occurs with the cell turnover and renewal during a period of morphological changes.  相似文献   
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A spontaneous lymphoid thymus tumor was discovered in a male Xenopus of the MHC ff genotype. The tumor cell can be transplanted in histocompatible larval ff hosts, but not in ff adults unless irradiated (3000 rad). The tumor is rejected by allogeneic hosts. The tumor cells express neither markers of the B-cell lineage nor MHC encoded molecules; they express only markers of the T-cell lineage. Its lymphoid population is clonal as revealed by the existence of a stable rearrangement pattern of the immunoglobulin genes. Cell lines growing continuously in vitro have been derived from the tumor.  相似文献   
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