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Benzo[k]fluoranthene (B[k]F) is one of numerous polycyclic aromatic hydrocarbons (PAHs) which is a persistent environmental contaminant in air and water. Upon B[k]F exposure, differential gene expression profiling was conducted in marine medaka fish (Oryzias javanicus) using subtractive hybridization. As a result, forty two differentially expressed candidate genes were induced in B[k]F-exposed fish as compared to control group, and the genes were associated with general metabolism, signal transduction, cell cycle, immune response, cytoskeleton, development, nucleotide/protein binding and some were non-categorized. These identified gene candidates have great potential to be developed as biomarkers for the identification of effects of B[k]F exposure in the environment. The results obtained in this study will offer insight to the physiological change induced by B[k]F exposure and will help assess the molecular mechanisms of B[k]F toxicity.  相似文献   
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Compression neuropathies   总被引:1,自引:0,他引:1  
Nerve compression, frequently from entrapment at specific anatomic locations, is a common clinical entity, especially in patients with predisposing occupations or with certain medical disorders. It should be pointed out that a nerve can be compressed at more than one level. Early recognition and treatment are the most effective means of preventing long-lasting disability, since, despite the capacity for regeneration bestowed on the peripheral nervous system, functions lost as a result of denervation are never fully restored.  相似文献   
96.
Cat sciatic nerves containing 2 and 4 cm nerve grafts were subjected to tensile testing with the finding that a significant decrease in force at failure occurs at the distal suture line at a time after surgery that is graft length dependent. Tritiated labeling of regenerating axons and qualitative electromyography demonstrated that this effect was unrelated to the leading edge of the axonal growth cone, but temporally related to the functional reinnervation of denervated muscle.  相似文献   
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In general, resistance to fluoroquinolones (FQs) in gram-negative bacteria is acquired either by mutations in DNA gyrase and topoisomerase IV or by active export of the agents via antibiotic efflux pumps. Reduced porin expression is also proposed to be another mechanism leading to resistance. In this study, interaction between levofloxacin, ofloxacin, and ciprofloxacin with MC-207,110 (multidrug efflux pump inhibitor) was investigated by a checkerboard assay using Pseudomonas aeruginosa. Levofloxacin, ofloxacin, and ciprofloxacin were tested at different concentrations (0.06-64 microg/ml) and MC-207,110 was tested at a concentration range of 4-128 microg/ml. In the presence of MC-207,110 (at 128, 64, 32, 16 microg/ml) resistance to FQs was inhibited significantly and MIC values were decreased, except at 8 and 4 microg/ml of MC-207,110. When MC-207,110 was used, resistance of P. aeruginosa to FQs in vitro was inhibited significantly, suggesting that MC-207,110 may be useful for use in clinical treatment protocols to overcome FQs resistance.  相似文献   
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The data about the fatty acid (FA) status of non-Hodgkin lymphoma (NHL) patients are poor. Therefore, the aim of this study was to investigate the FA profile of serum phospholipids in NHL patients related to the aggressiveness and clinical stage of NHL. We analyzed the FA profile of serum phospholipids in 47 newly diagnosed, untreated NHL patients and in 29 healthy subjects. Significantly higher (p?<?0.001) levels of palmitic (16:0), oleic (18:1 n-9) and arachidonic acids (20:4 n-6), saturated and monounsaturated FA were found in NHL patients, while linoleic acid (18:2 n-6) and the levels of total polyunsaturated FA (PUFA), n-3 PUFA, eicosapentaenoic (20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3) were significantly reduced (p?<?0.01). The level of oleic acid in patients with indolent NHL was significantly lower (p?<?0.05) than in more aggressive types of disease. Contents of palmitoleic acid, docosatetraenoic (22:4 n-6), and PUFA was lower in very aggressive NHL. According to clinical stage (CS), patients with CS I had significantly higher SFA and lower n-6 FA than other three groups, and group with CS IV showed significantly decreased DHA and n-3 PUFA. Our results showed an abnormal FA profile in serum phospholipids in NHL patients.  相似文献   
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