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111.
Our previous study indicated that 5-hydroxytryptamine (5-HT) immunoreactive fiber densities were decreased in specific areas of the brain in alcohol-preferring rats (P) when compared with alcohol-nonpreferring rats (NP). The results of our current study show that there are quantitative and qualitative differences in 5-HT innervation in other selected regions of the forebrains of P rats. The 5-HT fiber density in the brains of young adult P and NP rats was measured by immunocytochemistry and quantitative image analysis. A routine error of two-dimensional quantitation of nerve fiber was addressed and an adjustment was made. The amount of 5-HT fibers was significantly lower in CA4 and fasciola cinereum of the dorsal hippocampus, caudate-putamen, and hypothalamus of the P as compared with NP rats (unpaired Student's t tests). In examining the fiber types, we found that, in the frontal cortical and hippocampal regions, where normally fine 5-HT fibers with small varicosities and thick 5-HT fibers with large varicosities coexist, fewer fine 5-HT fibers were seen in P rats as compared with NP rats. The fine fibers are known to be vulnerable to abusive drugs. These observations indicate that (a) there are quantitative differences in 5-HT innervation or that the 5-HT in some 5-HT fibers is reduced to a level undetectable by immunocytochemistry, and (b) the fine 5-HT fibers are specifically reduced to a greater degree in the selected brain regions of P rats when compared with that of NP rats. The involvement of the 5-HT system in the alcohol abuse is discussed. 相似文献
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R Coszach T Delbar W Galster P Leleux I Licot E Liénard P Lipnik C Michotte A Ninane J Vervier CR Bain T Davinson RD Page AC Shotter PJ Woods D Baye F Binon P Descouvemont P Duhamel J Vanhorenbeeck M Vincke P Decrock M Huyse Van Duppen P G Vancraeynest FC Barker 《Canadian Metallurgical Quarterly》1994,50(3):1695-1701
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The wrist is a common site of injury in sports, both acute and chronic. Evaluation of wrist injuries requires knowledge of anatomy kinematics, attention to the mechanism of injury, the intensity of training, and a focus on the physical examination for specific injuries. 相似文献
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The presence of angiotensin II receptors was found on cells of three colorectal carcinoma cell lines. The binding assays with 125I-labelled angiotensin II and ligands specific for angiotensin AT1 or AT2 receptors showed that angiotensin receptors on colorectal cancer cells are mostly of the AT2 type. The binding capacity of tumor cells was not significantly changed by butyrate-induced differentiation. 相似文献