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51.
BACKGROUND & AIMS: Malondialdehyde and acetaldehyde react together with proteins and form hybrid protein conjugates designated as MAA adducts, which have been detected in livers of ethanol-fed rats. The aim of this study was to examine the immune response to MAA adducts and other aldehyde adducts during long-term ethanol exposure. METHODS: Rats were pair-fed for 7 months with a liquid diet containing either ethanol or isocaloric carbohydrate. Circulating antibody titers against MAA adducts and acetaldehyde adducts were measured and characterized in these animals. RESULTS: A significant increase in antibody titers against MAA-adducted proteins was observed in the ethanol-fed animals. Competitive inhibitions of antibody binding indicated that the circulating antibodies against MAA-modified proteins in the ethanol-fed rats recognized mainly a specific, chemically defined MAA epitope. Antibody titers to reduced and nonreduced acetaldehyde adducts were very low, and no significant differences were observed between ethanol-fed and control animals. Significant plasma immunoreactivity to not only MAA-adducted but also unmodified rat liver proteins (cytosol, microsomes, and especially plasma membrane) were also observed in the ethanol-fed rats. CONCLUSIONS: Long-term ethanol feeding generates circulating antibodies not only against MAA epitopes but possibly also against unmodified, native (self) protein epitopes, suggesting that MAA adducts could trigger harmful autoimmune responses.  相似文献   
52.
The measurement of intraoperative blood-loss during TUR is concerned as a compulsory procedure for this kind of operation. After testing so far known methods for measuring blood-volume in blood-water-mixtures and demonstrating greater disadvantages of these methods, we developed a new photometer, which allows an immediate and exact estimation of the blood-loss. We compared this new method with other also exact but more complicated methods, had laboratory tests and tests in the daily operative routine and excluded possible mistakes.  相似文献   
53.
Female patients suffering from perioral dermatitis were given the Raven Test, two personality inventories (MMPI and FPI) and the Rorschach Test. The results of these four tests show statistically significant differences from controls, indicating emotional immaturity combined with high intelligence level, inability to achieve satisfactory interpersonal relationships contrasting with an overemphasis upon social conformity, and a tendency to 'hysteriform' reactions.  相似文献   
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We present parameter estimation results for a full three-dimensional model of the human body with nearly 100 degrees of freedom. This task could only be achieved by the use of sophisticated numerical techniques not only for optimization but also for the model setup. We have developed an object-oriented biomechanical modeling library based on a special form of natural coordinates that does not only serve to establish the full set of equations of motion of highly complex biome-chanical systems, but also to efficiently compute all the derivative information that is required in the parameter estimation context. Our parameter estimation algorithm is based on a multiple shooting state discretization and uses a generalized Gauss–Newton method. Eight experiments are combined in a multiple experiment setting. Inconsistent initial values are treated by a special form of non-stiff Baumgarte relaxation.  相似文献   
56.
Separating the complex mixture that makes up brown-coal tar is very difficult if it consists largely of phenols, resins and carboxylic acids. By ethoxylating the ingredients that possess active hydrogen, they become water-soluble and can easily be removed from the mixture by aqueous extraction. Hydrocarbons can then be recovered and used. The extracted ingredients are valuable raw materials for industry.  相似文献   
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Comparative Analysis of Volatile Constituents from Mice and their Urine   总被引:1,自引:0,他引:1  
We report the volatile composition of the body scent of male C57BL/6J mice in comparison to the volatile composition of their urine. From a total of 67 components, nitromethane, propanoic acid, dimethyldisulfide, 1-octene, 1-hexanol, hexanoic acid, indole, α- and β-farnesene, and one unidentified component were observed only in the volatiles from the body of mice. On the other hand, 3-penten-2-one, 3-methyl-2-buten-1-ol, 3-methyl-cyclopentanone, p-xylene, 3-hepten-2-one, 2,3-dehydro-exo-brevicomin, benzylmethylketone, and 13 unidentified components were only found in urine volatiles. All other substances were present in the volatiles of both mice and their urine. Aliphatic aldehydes from pentanal to decanal were prominent mouse odor components. Because receptors for these aldehydes have been extensively characterized in the main olfactory organ, these components may be important for mice in recognizing their conspecifics.Electronic Supplementary Material Supplementary material is available in the online version of this article at and is accessible for authorized users.  相似文献   
59.
Pb(Zr,Ti)O3 (PZT) thin films deposited on insulating ZrO2 buffered silicon wafer are intended to be employed for in-plane polarized piezoelectric MEMS devices. Multi-target reactive sputtering system for large area deposition of in-situ crystallized PZT thin films and the ZrO2 buffer layer has been employed. The interface analysis of multilayer structures by high resolution transmission microscope, X-ray diffraction, optical refraction, and absorption spectra studies has been presented. At a substrate temperature of 520°C and excess lead deposition condition, the formation of a PZT superstructure has been revealed. The substrate temperature of 580°C leads to the crystallization of PZT directly into a single phase perovskite crystal structure. A pronounced Urbach behavior in our PZT thin films has been observed by optical absorption studies. The surface roughness of PZT films deposited on a ZrO2 buffer layer is much higher than that on conducting platinized silicon wafer.  相似文献   
60.
Selective targeting of DNA by means of fluorescent labeling has become a mainstay in the life sciences. While genetic engineering serves as a powerful technique and allows the visualization of nucleic acid by using DNA-targeting fluorescent fusion proteins in a cell-type- and subcellular-specific manner, it relies on the introduction of foreign genes. On the other hand, DNA-binding small fluorescent molecules can be used without genetic engineering, but they are not spatially restricted. Herein, we report a photocaged version of the DNA dye Hoechst33342 (pcHoechst), which can be uncaged by using UV to blue light for the selective staining of chromosomal DNA in subnuclear regions of live cells. Expanding its application to a vertebrate model organism, we demonstrate uncaging in epithelial cells and short-term cell tracking in vivo in zebrafish. We envision pcHoechst as a valuable tool for targeting and interrogating DNA with precise spatiotemporal resolution in living cells and wild-type organisms.  相似文献   
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