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101.
Tumor necrosis factor (TNF) is a cytokine that possesses many biological activities, including enhancement of non-rapid-eye-movement sleep (NREMS). The role of endogenous TNF in the regulation of spontaneous sleep is unknown. If TNF is involved in sleep regulation, then reduction of endogenous TNF should suppress spontaneous sleep. A soluble TNF-binding protein I (TNF-BP I) and a synthetic fragment of TNF-BP I, TNF-R-(159–178), that contains the biologically active region of TNF-BP I, were used. These substances bind TNF and possess TNF-inhibitory activity; their effects on rabbit sleep after intracerebroventricular injection were determined across a 6-h recording period. Two doses of TNF-BP I (0.05 g and 0.5 g) were administered; the higher dose of TNF-BP I significantly decreased NREMS. Four doses of TNF-R-(159–178) (0.25 g, 2.5 g, 25 g and 50 g) were used. The 25 g and 50 g doses significantly suppressed NREMS. The highest dose (50 g) also decreased REM sleep. These results are consistent with the hypothesis that endogenous brain TNF is involved in the regulation of normal sleep.  相似文献   
102.
Lack of efficient culture systems for hepatitis C virus (HCV) has been a major obstacle in HCV research. Human liver cells grown in a three-dimensional radial-flow bioreactor were successfully infected following inoculation with plasma from an HCV carrier. Subsequent detection of increased HCV RNA suggested viral replication. Furthermore, transfection of HCV RNA transcribed from full-length cDNA also resulted in the production and release of HCV virions into supernatant. Infectivity was shown by successful secondary passage to a new culture. Introduction of mutations in RNA helicase and polymerase regions of HCV cDNA abolished virus replication, indicating that reverse genetics of this system is possible. The ability to replicate and detect the extracellular release of HCV might provide clues with regard to the persistent nature of HCV infection. It will also accelerate research into the pathogenicity of HCV, as well as the development of prophylactic agents and new therapy.  相似文献   
103.
In order to investigate superoxide production by pulmonary macrophages in the rat, a route was created by ligating both the inferior and superior venae cavae and resecting the aorta after cannulation through the inferior vena cava into the right atrium of the heart. Lung perfusion was performed via this route with nitro blue tetrazolium. Although there was no formazan deposition throughout the lung, it became detectable in both alveolar and interstitial macrophages when phorbol myristate acetate was added to the perfusate. This deposition was markedly enhanced by previous injection of Corynebacterium parvum. The deposition disappeared after further addition of Cu(Lys)2, a scavenger of superoxide anions. This procedure may be useful for estimating in situ the ability of pulmonary macrophages to produce superoxide in the rat.  相似文献   
104.
The caudal part of the fastigial nucleus, or the fastigial oculomotor region (FOR), plays an important role in executing accurate saccades. Inactivation of a monkey FOR leads to dysmetric saccades. Currently available data suggest that the dysmetria could be described as a parametric, uniform change in saccadic gain or, alternatively, as a constant error in the specification of the saccadic goal. To discriminate between these two possibilities, we examined the effect of FOR inactivation in the monkey. After a unilateral injection of muscimol into the FOR, ipsiversive saccades overshot a target. Gains were similar for movements of different sizes. The overshoot increased proportionately with the target distance and had a very small constant component. The present study indicates that the hypermetria of ipsiversive saccades after inactivation of the monkey FOR is primarily due to a uniform gain increase for all sizes of saccades.  相似文献   
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To evaluate the potential role of NK1.1 (CD161c) cells in autoimmune uveoretinitis, we treated experimental autoimmune uveoretinitis (EAU)-susceptible mice with anti-CD161c antibodies (PK136) to deplete natural killer (NK) cells. Injection of anti-CD161c antibodies deleted NK cells from the peripheral blood of EAU-susceptible mice. The T cell proliferative response against the ocular autoantigen K2 was not suppressed in mice treated with anti-CD161c antibody when compared with T cells from control mice. Although mice treated with anti-CD161c developed EAU, the clinical severity on days 17 and 19 after induction of EAU was significantly mild in anti-CD161c-treated mice compared with control mice. In addition, the histopathological severity of EAU was significantly milder in mice treated with anti-CD161c antibodies than controls 21 days after induction of EAU. Our results indicate that the severity of EAU is augmented by NK1.1(+) NK cells.  相似文献   
108.
A simple membrane immunoassay assay system, Quik Pack, for the detection of hepatitis C virus antibody was compared with two enzyme-linked immunosorbent assays (ELISAs) in a study of 600 serum samples. Quik Pack exhibited excellent sensitivity and specificity: 96.0 and 99.7%, respectively, versus the ELISA-2 and 99.7 and 99.4%, respectively, versus the ELISA-3.  相似文献   
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