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571.
Cultures of glial cell lines (C6) were exposed to 10-micromilligram Dexamethasone which is known to cause morphological differentiation and induction of 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) in these cells. Ethanol in a concentration of 1.5% abolished these responses, and at 1% diminished them.  相似文献   
572.
Allergic asthma is dependent on chemokine-mediated Th2 cell migration and Th2 cytokine secretion into the lungs. The inducible T cell tyrosine kinase Itk regulates the production of Th2 cytokines as well as migration in response to chemokine gradients. Mice lacking Itk are resistant to developing allergic asthma. However, the role of kinase activity of Itk in the development of this disease is unclear. In addition, whether distinct Itk-derived signals lead to T cell migration and secretion of Th2 cytokines is also unknown. Using transgenic mice specifically lacking Itk kinase activity, we show that active kinase signaling is required for control of Th2 responses and development of allergic asthma. Moreover, dominant suppression of kinase Itk activity led to normal Th2 responses, but significantly reduced chemokine-mediated migration, resulting in prevention of allergic asthma. These observations indicate that signals required for Th2 responses and migration are differentially sensitive to Itk activity. Manipulation of Itk's activity can thus provide a new strategy to treat allergic asthma by differentially affecting migration of T cells into the lungs, leaving Th2 responses intact.  相似文献   
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Senescence of Detached Fern Leaves   总被引:1,自引:0,他引:1  
Detached fern leaves show a loss in the content of pigments,protein and a decline in 2,6-dichlorophenol indophenol Hillreaction of isolated chloroplasts during aging. Light treatmentof leaves could considerably retard aging induced loss in 2,6-dichlorophenolindophenol photoreduction but it exhibits less effect on pigmentand protein loss. (Received February 7, 1983; Accepted July 14, 1983)  相似文献   
575.
Plasmonics - A complementary metal oxide semiconductor (CMOS) compatible photonic-plasmonic waveguide with nanoscale dimensions and better optical confinement has been proposed for the infrared...  相似文献   
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Self-association of α-synuclein (αS) into pathogenic oligomeric species and subsequent formation of highly ordered amyloid fibrils is linked to the Parkinson’s disease. So most of the recent studies are now focused on the development of potential therapeutic strategies against this debilitating disease. β-synuclein (βS), a presynaptic protein that co-localizes with αS has been recently reported to act as an inhibitor of αS self-assembly. But the specificity of molecular interaction, nature and location between αS/βS is not known despite the potential importance of βS as an inhibitor of αS. We used molecular dynamics and potential of mean force (PMF) to study association of αS/βS and αS/αS. The calculated PMF indicates that contact wells are significantly deeper and presence of a minimum at αS/βS separation of 13.5 Å with a free energy barrier of 40 kcal/mol. We observed the dissociation energy barrier to be two times higher for the hetero-dimer (αS/βS) than the homo-dimer (αS/αS). We also carried out umbrella samplings involving two degrees of freedom (one being the distance between the monomeric units and the other angle between the long axes of the two monomeric chains) and observed similar PMF profile. We noticed relatively stronger range of transient interactions between the monomeric units in hetero-dimer (αS/βS) than homo-dimer (αS/αS). So our findings suggest that αS readily combines with βS to form hetero-dimer than combining with itself in forming homo-dimer. Hence we see predominant transient interactions between αS and βS can be used to drive inhibition of αS aggregation.  相似文献   
579.
We investigated the utility of the fluorescent dye Deep Red Anthraquinone 5 (DRAQ5) for digital staining of optically sectioned skin in comparison to acridine orange (AO). Eight fresh-frozen thawed Mohs discard tissue specimens were stained with AO and DRAQ5, and imaged using an ex vivo confocal microscope at three wavelengths (488 nm and 638 nm for fluorescence, 785 nm for reflectance). Images were overlaid (AO + Reflectance, DRAQ5 + Reflectance), digitally stained, and evaluated by three investigators for perceived image quality (PIQ) and histopathological feature identification. In addition to nuclear staining, AO seemed to stain dermal fibers in a subset of cases in digitally stained images, while DRAQ5 staining was more specific to nuclei. Blinded evaluation showed substantial agreement, favoring DRAQ5 for PIQ (82%, Cl 75%-90%, Gwet's AC 0.74) and for visualization of histopathological features in (81%, Cl 73%-89%, Gwet's AC 0.67), supporting its use in digital staining of multimodal confocal micrographs of skin.  相似文献   
580.
Intracranial hypotension (IH) is a pathophysiological condition of reduced intracranial pressure caused by low cerebrospinal fluid (CSF) volume due to dural injuries from lumbar puncture, surgery, or trauma. Understanding the prognosis of IH in small animal models is important to gain insights on the complications associated with it such as orthostatic headache, cerebral venous thrombosis, coma, and so forth. Photoacoustic tomography (PAT) offers a novel and cost‐effective way to perceive and detect IH in small animal models. In this study, a pulsed laser diode (PLD)‐based PAT imaging system was used to examine the changes in the venous sinuses of the rat brain due to IH, induced through CSF extraction. After the CSF extraction, an increase in the sagittal sinus area by ~30% and width by 40% ± 5% was observed. These results provide supportive evidence that the PLD‐PAT can be employed for detecting changes in sagittal sinus due to IH in rat model.  相似文献   
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