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461.
High doses of light can cause damage to the retina, e.g. during intraocular surgery. Previously, thiols have been demonstrated to protect against retinal damage in various damage models. Such protection is very promising for clinical practice. Retinal light damage can be caused by a relatively short exposure to high irradiance levels. These conditions occur during intraocular surgery. In the current study we therefore investigated whether the thiol N-acetylcysteine protects against retinal light damage under high irradiance conditions in the rat retina. Two stereoisomers of this thiol were tested for protection against two spectrally defined types of retinal light damage. Shortly after administration N-acetyl-L-cysteine in doses of 270-1000 mg/kg intraperitoneally protected against 380 nm (UVA) light but not against 470 nm (blue) light. Two hours after injection the protection had diminished. We observed no protection by the stereoisomer N-acetyl-D-cysteine. From this study we conclude that N-acetyl-L-cysteine protects stereospecifically against retinal damage in the UV but not in the visible part of the spectrum. This limits the possible applications.  相似文献   
462.
Raman and infrared spectroscopy enabled insights into the molecular structure of the sampleite group of minerals. These minerals are based upon the incorporation of either phosphate or arsenate with chloride anion into the structure, and as a consequence the spectra reflect the bands attributable to these anions, namely, phosphate or arsenate with chloride. The sampleite vibrational spectrum reflects the spectrum of the phosphate anion and consists of ν1 at 964 cm−1, ν2 at 451 cm−1, ν3 at 1016 and 1088 cm−1 and ν4 at 643, 604, 591 and 557 cm−1. The lavendulan spectrum consists of ν1 at 854 cm−1, ν2 at 345 cm−1, ν3 at 878 cm−1 and ν4 at 545 cm−1. The Raman spectrum of lemanskiite is different from that of lavendulan consistent with a different structure. Low wavenumber bands at 227 and 210 cm−1 may be assigned to CuCl transverse/longitudinal (TO/LO) optic vibrations. Raman spectroscopy identified the substitution of arsenate by phosphate in zdenekite and lavendulan. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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In the framework of values for TU-games, it is shown that a particular type of consistency, called linear consistency, together with some kind of standardness for two-person games, imply efficiency, anonymity, linearity, as well as uniqueness of the value. Among others, this uniform treatment generalizes Sobolev's axiomatization of the Shapley value. Revised version: December 2001  相似文献   
467.
Every compact disconnected projective plane can be written as an inverse limit of finite discrete incidence structures. Every finite projective plane is a continuous epimorphic image of some compact disconnected projective plane. There exist compact disconnected projective planes of Lenz type V which do not admit any continuous epimorphism onto a finite projective plane.Supported in part by a travel grant of the Deutsche Forschungsgemeinschaft.  相似文献   
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