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11.
Real-time ultrasonic echo imaging of peripheral arteries promises to facilitate the management of selected patients with peripheral and extracranial arterial disease. This report outlines the technique of imaging the carotid system and portions of the arteries that supply the lower extremities. It also discusses the normal and pathologic anatomy of these arteries.  相似文献   
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Peroxisome proliferator-activated receptors (PPAR) are members of a nuclear hormone receptor superfamily that includes receptors for steroids, retinoids, and thyroid hormone, all of which are known to affect the immune response. Previous studies dealing with PPAR-gamma expression in the immune system have been limited. Recently, PPAR-gamma was identified in monocyte/macrophage cells. In this study we examined the role of PPAR-gamma in experimental autoimmune encephalomyelitis (EAE), an animal model for the human disease multiple sclerosis. The hypothesis we are testing is whether PPAR-gamma plays an important role in EAE pathogenesis and whether PPAR-gamma ligands can inhibit the clinical expression of EAE. Initial studies have shown that the presence of the PPAR-gamma ligand 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ2) inhibits the proliferation of Ag-specific T cells from the spleen of myelin basic protein Ac(1-11) TCR-transgenic mice. 15d-PGJ2 suppressed IFN-gamma, IL-10, and IL-4 production by both Con A- and myelin basic protein Ac(1-11) peptide-stimulated lymphocytes as determined by ELISA and ELISPOT assay. Culture of encephalitogenic T cells with 15d-PGJ2 in the presence of Ag reduced the ability of these cells to adoptively transfer EAE. Examination of the target organ, the CNS, during the course of EAE revealed expression of PPAR-gamma in the spinal cord inflammatory infiltrate. Administration of 15d-PGJ2 before and at the onset of clinical signs of EAE significantly reduced the severity of disease. These results suggest that PPAR-gamma ligands may be a novel therapeutic agent for diseases such as multiple sclerosis.  相似文献   
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In this study we designed, implemented, and evaluated an outreach programme for high-school biology students rooted in the ‘science as inquiry’ approach. Accordingly, students learn about science from experts in the field, as well as through in-class exposure to the history and philosophy of science. Our sample consisted of 11th graders (n?=?497), ages 16–17, attending advanced biology classes. Our goal was to determine whether this programme had a significant effect on students’ understanding of the ‘nature of science’ (NOS) and on their attitudes towards science. Using a controlled pre-post research design, we asked participants to complete a Likert-like questionnaire. Also, we conducted post-programme semi-structured interviews with 35 of the participants. Results show that completion of the programme significantly enhanced participants’ NOS understanding and improved their attitudes towards science. Participants expressed a deep level of NOS understanding and explicitly stated that the field visits to experts’ labs had changed their attitude towards science. We believe that our outreach programme can be adapted for teaching other sciences and for societies worldwide, as long as there is access to university laboratories and researchers willing to interact with young citizens and potential future scientists.  相似文献   
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Protein homeostasis depends on a balance of translation, folding, and degradation. Here, we demonstrate that mild inhibition of translation results in a dramatic and disproportional reduction in production of misfolded polypeptides in mammalian cells, suggesting an improved folding of newly synthesized proteins. Indeed, inhibition of translation elongation, which slightly attenuated levels of a copepod GFP mutant protein, significantly enhanced its function. In contrast, inhibition of translation initiation had minimal effects on copepod GFP folding. On the other hand, mild suppression of either translation elongation or initiation corrected folding defects of the disease-associated cystic fibrosis transmembrane conductance regulator mutant F508del. We propose that modulation of translation can be used as a novel approach to improve overall proteostasis in mammalian cells, as well as functions of disease-associated mutant proteins with folding deficiencies.  相似文献   
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The structure–activity relationships for a series of heteroaryl urea inhibitors of fatty acid amide hydrolase (FAAH) are described. Members of this class of inhibitors have been shown to inactivate FAAH by covalent modification of an active site serine with subsequent release of an aromatic amine from the urea electrophile. Systematic Ames II testing guided the optimization of urea substituents by defining the structure–mutagenicity relationships for the released aromatic amine metabolites. Potent FAAH inhibitors were identified having heteroaryl amine leaving groups that were non-mutagenic in the Ames II assay.  相似文献   
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The early stages of sporulation in Bacillus subtilis incorporate a modified, highly asymmetric cell division. It is now clear that most, if not all, of the components of the vegetative division machinery are used also for asymmetric division. However, the machinery for chromosome segregation may differ significantly between vegetative growth and sporulation. Several interesting checkpoint mechanisms couple cell cycle events to gene expression early in sporulation. This review summarises important advances in the understanding of chromosome segregation and cell division at the onset of sporulation in B.subtilis in the past three years.  相似文献   
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