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Chronically elevated levels of corticotropin-releasing factor (CRF) in transgenic mice overexpressing CRF in the brain (CRF-OE) appear to be associated with alterations commonly associated with major depressive disorder, as well as with sensorimotor gating deficits commonly associated with schizophrenia. In the present study, we tested the hypothesis that antipsychotics may be effective in normalizing prepulse inhibition (PPI) of acoustic startle in CRF-OE mice, which display impaired sensorimotor gating compared to wild-type (WT) mice. The typical antipsychotic haloperidol and atypical antipsychotic risperidone improved PPI in the CRF-OE mice, but were ineffective in WT mice. The atypical antipsychotic clozapine did not influence PPI in CRF-OE mice, but reduced gating in WT mice. This effect of clozapine in the CRF-OE mice may thus be regarded as a relative improvement, consistent with the observed effect of haloperidol and risperidone. As expected, the anxiolytic, nonantipsychotic chlordiazepoxide was devoid of any effect. All four compounds dose-dependently reduced the acoustic startle response irrespective of genotype. These results indicate that antipsychotic drugs are effective in improving startle gating deficits in the CRF-OE mice. Hence, the CRF-OE mouse model may represent an animal model for certain aspects of psychotic depression, and could be a valuable tool for research addressing the impact of chronically elevated levels of CRF on information processing.  相似文献   
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The synthesis and properties of segmented ABA triblock and (AB)n multiblock copolymer systems with 6,6′-disubstituted 2,2′-bipyridine (bpy) building blocks B and poly(oxytetramethylene) soft segments A are described. The access to the disubstituted bipyridines in large scale quantities was achieved by modification of conventional synthetic routes. In the presence of copper(I) ions these polymers formed mononuclear [Cu(I)(bpy)2] complexes in solution through self-assembly. The complexed copolymers were microphase separated systems in bulk with nano to mesoscopic superstructures consisting of copper-bpy complex aggregates in a polyether matrix. The thermal, mechanical and elastomer properties of the block copolymers varied with composition.  相似文献   
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A report is presented on two patients who received surgery on a disc prolapse between the lumbar vertebrae 4 and 5 as treatment for compression of the fifth lumbar root, but in whom the clinically relevant disc prolapse was located higher (lumbar vertebrae 1/2 or thoracic vertebra 12/lumbar vertebra 1). Magnetic resonance tomography made a major contribution to the later diagnosis of the high disc prolapses. Besides precise localization of the lesion, MRT made it easier to understand why such a high disc prolapse can cause a compression syndrome of the fifth lumbar root.  相似文献   
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BACKGROUND: In LBP patients, the relationship between pain and physical activity remains unclear. Whereas a negative relationship between pain and self-reported physical activity was found, this relation disappeared in the case of overt behavioral data (e.g., accelerometer). Cognitive-behavioral models of the development of chronic pain suggest subgroups with signs of physical underuse and overuse. AIMS: To examine if patients with pain-related adaptive, endurance and fear-avoidance coping differ in pain, self-reported physical function and overt physical activity 6 months after disc surgery. METHODS: 24 patients completed questionnaires (Von Korff chronic pain grade (CPG), Kiel pain inventory (KPI), Funktionsfragebogen Hannover-Rücken FFbH-R) and underwent an 8-h accelerometer assessment in their daily life (physical activity level (PAL), number of constant postures (CP)). The KPI differed between adaptive coping (AC) (N=9), fear avoidance coping (FAC) (N=1) and endurance coping (EC) (N=14). RESULTS: In the whole group, pain intensity was negative related to self-reported physical activity whereas PAL and CP displayed no correlation with pain. EC patients showed significantly higher pain scores and lower self-reported physical functioning compared to AC but the same level of PAL and furthermore, a significantly higher number of CPs in daily life. The visual inspection of the FAC patient revealed also high pain, low physical functioning and low overt physical activity. CONCLUSIONS: The assessment of pain-related coping modes yielded an important differentiation between subgroups of LBP patients 6 months after surgery. Endurance copers displayed signs of overuse in their daily behavior in spite of pain than adaptive copers. The one fear avoidance coper tends to do less physical activity in the sense of underuse.  相似文献   
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The complement system (C) is one of the main humoral components of innate immunity. Three major tasks of C against invading pathogens are: (i) lysis of pathogens by the formation of the membrane attack complex (MAC); (ii) opsonization of pathogens with complement fragments to favor phagocytosis; and (iii) attraction of inflammatory cells by chemotaxis. Like other particles, HIV activates C and becomes opsonized. To escape complement-mediated lysis, HIV has adopted various properties, which include the acquisition of HIV-associated molecules (HAMs) belonging to the family of complement regulators, such as CD46, CD55, CD59, and the interaction with humoral regulatory factors like factor H (fH). Opsonized virus may bind to complement receptor positive cells to infect them more efficiently or to remain bound on the surface of such cells. In the latter case HIV can be transmitted to cells susceptible for infection. This review discusses several aspects of C-HIV interactions and provides a model for the dynamics of this process.  相似文献   
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