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81.
Leukemia inhibitory factor (LIF) and oncostatin M (OSM), two pleiotropic cytokines involved in bone remodeling, have both anabolic and catabolic activities. This study analyzed the effects of LIF and OSM on the physicochemical characteristics of mineral phases formed in a rat bone-marrow stromal cell culture model. Stromal cells were cultured for three weeks in the presence of 10(-8) M dexamethasone, 50 microgram/mL ascorbic acid and 10 mM Na beta-glycerophosphate with or without 10 ng/ml LIF or OSM. Subsequently, the physicochemical characteristics of the mineralization nodules formed were analyzed by energy dispersive X ray microanalysis (EDX) and Fourier transform-infrared (FT-IR) and FT-Raman spectroscopy. EDX and FT-IR spectroscopy revealed the influence of LIF and OSM on the physicochemical characteristics of mineral phases. FT-Raman spectroscopy showed modifications of the main vibrational modes of the organic matrix. These alterations induced by growth factors could help define new strategies for the prevention and treatment of skeletal disorders.  相似文献   
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Abstract

C60 was treated at room temperature, in air with intense ultrasound in the following solvents; decalin, tetralin. cyclohexane and CCl4. It is shown by UV-VIS and FT-IR spectroscopy that in decalin and in tetralin the dominant reaction seems to be a sono-oxidation, although more complex reactions involving the solvent take place. In CC14 sono-oxidation is accompanied by an extensive sono-polymerization. Products in CCl4 are C60O, C60O2 and others; the sonopolymer collected from sonicated CCl4 was easily identified by FT-IR spectroscopy. Sonopolymerization occurs also in decalin and tetralin and is promoted by free radicals as in the case of CCl4. No reactions are observed in cyclohexane due to the very low solubility of C60 in this solvent and the poor cavitation ability of cyclohexane under the action of ultrasound.  相似文献   
84.
Nowadays it is possible to unravel complex information at all levels of cellular organization by obtaining multi-dimensional image information. At the macromolecular level, three-dimensional (3D) electron microscopy, together with other techniques, is able to reach resolutions at the nanometer or subnanometer level. The information is delivered in the form of 3D volumes containing samples of a given function, for example, the electron density distribution within a given macromolecule. The same situation happens at the cellular level with the new forms of light microscopy, particularly confocal microscopy, all of which produce biological 3D volume information. Furthermore, it is possible to record sequences of images over time (videos), as well as sequences of volumes, bringing key information on the dynamics of living biological systems. It is in this context that work on BioImage started two years ago, and that its first version is now presented here. In essence, BioImage is a database specifically designed to contain multi-dimensional images, perform queries and interactively work with the resulting multi-dimensional information on the World Wide Web, as well as accomplish the required cross-database links. Two sister home pages of BioImage can be accessed at http://www. bioimage.org and http://www-embl.bioimage.org  相似文献   
85.
A search was made for C60 fullerene by High Performance Liquid Chromatography in char formed on a Norway Spruce struck by lightning. Firm proof that C60 occurs in the char was not obtained. However, the evidence showed the possible presence of 1 ppb C60.  相似文献   
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Image texture features as indicators of beef tenderness   总被引:3,自引:0,他引:3  
Li J  Tan J  Martz FA  Heymann H 《Meat science》1999,53(1):17-22
Image processing techniques were developed to predict cooked-beef tenderness from fresh-beef image characteristics. Cattle from different finishing treatments were processed in a commercial plant. Two short loin steaks were sampled from each carcass; one used for sensory evaluation and the other for imaging. The samples varied significantly in both US quality grades and sensory tenderness scores. Color, marbling and texture features were extracted from the beef images. Statistical and neural network analyses were performed to relate the image features to sensory tenderness scores. Image texture features were found to be useful indicators of beef tenderness. Partial least squares and neural network models were able to predict beef tenderness from color, marbling and image texture features to R(2)-values up to 0.70.  相似文献   
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A noise model based on an equivalent circuit is applied to an HEMT. Besides the frequency dependence of the most important noise parameters (F/sub min/, R/sub opt/, X/sub opt/, R/sub N/) two apparent experimental facts are explained: the limited R/sub opt/, X/sub opt/ and the increase of R/sub N/ with decreasing frequency.<>  相似文献   
90.
An absorbable, non-toxic, easy gliding, cross-linked gelatine tube has been developed to prevent and to treat chronical adhesion ileus. The tube is patterned upon the interior intestinal splinting with long tubes. By doing a small enterotomy it was possible to splint the whole intestine in pigs or endangered parts within a few minutes. The flexible gelatine tube does not kink and is melting off from the surface. It prevents the intestine from kinking and does not cause any lesions even on previously damaged intestinal walls. Possible complications seen by insertion and extraction of conventional tubes were not observed.  相似文献   
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