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Detrimental immune response has a crucially important role in the development and progression of inflammatory eye diseases. Inflammatory mediators and proteolytic enzymes released by activated immune cells induce serious injury of corneal epithelial cells and retinal ganglion cell which may result in the vision loss. Mesenchymal stem cells (MSCs) are regulatory cells which produce various immunosuppressive factors that modulate phenotype and function of inflammatory immune cells. However, several safety issues, including undesired differentiation and emboli formation, limit clinical use of MSCs. MSC-derived exosomes (MSC-Exos) are nano-sized extracellular vesicles which contain all MSC-derived immunoregulatory factors. Intraocular administration of MSC-Exos efficiently attenuated eye inflammation and significantly improved visual acuity in experimental animals without causing any severe side effects. As cell-free product, MSC-Exos addressed all safety issues related to the transplantation of MSCs. Therefore, MSC-Exos could be considered as potentially new remedy for the treatment of inflammatory eye diseases which efficacy should be explored in up-coming clinical trials.  相似文献   
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Forage grasses and legumes growing in the soil covering four coal fly ash landfill sites in Central New York were sampled and analyzed for 20 elements. Selenium, boron and molybdenum were most consistently higher in concentration in these crops than the corresponding control plants sampled from adjacent upwind locations. Legumes absorbed greater amounts of these elements than grasses probably owing to their deep-rooted penetration of the fly ash layer below. Factors affecting the extent of absorption of these elements by the crops and the agricultural significance as related to grazing farm animals are discussed.  相似文献   
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Self-knowledge is a concept that is present in several philosophies. In this article, we consider the issue of whether or not a learning algorithm can in some sense possess self-knowledge. The question is answered affirmatively. Self-learning inductive inference algorithms are taken to be those that learn programs for their own algorithms, in addition to other functions.
La connaissance de soi est un concept qui se retrouve dans plusieurs philosophies. Dans cet article, les auteurs s'interrogent à savoir si un algorithme d' apprentissage peut dans une certaine mesure posséder la connaissance de soi. lis apportent une reponse positive a cette question. Les algorithmes d'inference inductive autodidactes sont ceux qui font l'apprentissage de programmes pour leurs propres algorithmes, en plus d' autres fonctions.  相似文献   
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Transboundary impact assessment (TIA) has become an important environmental management tool, particularly where a project may have transboundary impacts. With the growing practice of TIA, it becomes important to consider the accuracy of the transboundary impact assessments that are being conducted. If TIA is a planning tool designed to provide a basis for making an informed decision, does it actually provide the necessary information? This paper summarizes lessons learned in pilot testing a methodology to assess the accuracy of TIAs.  相似文献   
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The phase equilibrium diagram for the system La2O3-B2O3 has been determined experimentally. The compounds La2O3-3B2O3and La2O3-B2O3 melt congruently at 1141°± 5°C. and 1660°± 15°C, respectively. At 1488°± 5°C, La2O3-B2O3 inverts from the aragonite-type structure to a high-temperature form. Trilanthanum borate, 3La2O3 B2O3, melts incongruently at 1386°± 5°C. to give liquid and La2O3. No solid solutions exist in the system. A region of liquid immiscibility exists in the system and extends at 1136°± 5°C. from almost pure B2O3 to 21.5 mole % La2O3. The experimental value for the extent of immiscibility agrees with that calculated from theoretical considerations. A second method for estimating immiscibility in the system is demonstrated, which requires experimentally only the determination of the index of refraction of the modifier-rich liquid. Principles governing immiscibility are discussed.  相似文献   
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