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排序方式: 共有2051条查询结果,搜索用时 15 毫秒
161.
CS Sommardahl RP Woychik WE Sweeney ED Avner JE Wilkinson 《Canadian Metallurgical Quarterly》1997,11(6):728-733
Studies on conscious Sprague-Dawley rats using intracerebral dialysis in live animals combined with high-performance liquid chromatography with electrochemical detection showed that administration of apomorphine into the nucleus accumbens decreased the levels of dihydroxyphenylacetic acid and 5-hydroxyindoleacetic acid in the extracellular space of the dorsal striatum throughout the observation period and produced a transient reduction in the level of homovanillic acid in the dialysate from this structure. The studies demonstrated that reversible exclusion of the nucleus accumbens with procaine produced a transient increase in the levels of dopamine metabolites, without an increase in serotonin metabolites, in the extracellular space of the dorsal striatum. These results demonstrate that the nucleus accumbens affects dopamine metabolism in the striatum, this being mediated by the dopamine-reactive system in the nucleus accumbens. 相似文献
162.
H Okazaki J Zhang MM Hamawy RP Siraganian 《Canadian Metallurgical Quarterly》1997,272(51):32443-32447
Aggregation of the FcepsilonRI, a member of the immune receptor family, induces the activation of proteintyrosine kinases and results in tyrosine phosphorylation of proteins that are involved in downstream signaling pathways. Here we report that Pyk2, another member of the focal adhesion kinase family, was present in the RBL-2H3 mast cell line and was rapidly tyrosine-phosphorylated and activated after FcepsilonRI aggregation. Tyrosine phosphorylation of Pyk2 was also induced by the calcium ionophore A23187, by phorbol myristate acetate, or by stimulation of G-protein-coupled receptors. Adherence of cells to fibronectin dramatically enhanced the induced tyrosine phosphorylation of Pyk2. Although Src family kinases are activated by FcepsilonRI stimulation and tyrosine-phosphorylate the receptor subunits, the activation and tyrosine phosphorylation of Pyk2 were downstream of Syk. In contrast, tyrosine phosphorylation of Pyk2 by stimulation of G-protein-coupled receptors was independent of Syk. Therefore, the FcepsilonRI-induced tyrosine phosphorylation of Pyk2 is downstream of Syk and may play a role in cell secretion. 相似文献
163.
Y Horie RP Chervenak R Wolf ME Gerritsen DC Anderson S Komatsu DN Granger 《Canadian Metallurgical Quarterly》1997,159(10):5053-5062
TNF-alpha is known to elicit a rapid increase in the expression of specific endothelial cell adhesion molecules (ECAMs) within different vascular beds. The aim of this study was to determine whether lymphocytes contribute to the increased ECAM expression elicited by TNF-alpha. A dual radiolabeled mAb technique was used to quantify constitutive and TNF-alpha-induced expression of ICAM-1, VCAM-1, E-selectin, and P-selectin in different vascular beds (lung, heart, stomach, mesentery, small intestine, large intestine, and muscle) in wild-type and SCID mice. In reconstitution experiments, either whole splenocytes, T cell-enriched splenocytes, or B cell-enriched splenocytes were injected into SCID mice 48 h before TNF-alpha administration. Although the constitutive expression of ECAMs differed only slightly between wild-type and SCID mice, TNF-alpha-induced ECAM expression was markedly blunted in SCID mice compared with wild-type mice. This blunted response to TNF-alpha was also demonstrated for VCAM-1 in recombination activating gene (RAG)-1 mutant mice. Reconstitution studies revealed that administration of 50 x 10(6) splenocytes in SCID mice at 48 h before cytokine treatment restored the TNF-alpha-induced expression of VCAM-1 to levels normally observed in wild-type mice. Reconstitution with T cell- but not B cell-enriched splenocytes, also restored the TNF-alpha-induced expression of VCAM-1 in SCID mice to wild-type levels. These results implicate circulating T lymphocytes as modulators of the increased ECAM expression elicited by TNF-alpha. 相似文献
164.
Concentrations and emission rates of aerial ammonia, nitrous oxide, methane, carbon dioxide, dust and endotoxin in UK broiler and layer houses 总被引:2,自引:0,他引:2
CM Wathes MR Holden RW Sneath RP White VR Phillips 《Canadian Metallurgical Quarterly》1997,38(1):14-28
Standard treatment for limited stage adenocarcinoma of the breast includes lumpectomy (or a quadrantectomy), axillary node dissection, regional radiation therapy and, if the prognostic factors are unfavourable, chemotherapy and/or hormone therapy. This is supported by the results of American and European randomised trials. There have been many attempts at improving the modalities of conservative surgery and postoperative radiation therapy in order to maximize local control and minimize late sequellae. It is also likely that induction chemotherapy and external beam radiotherapy applied in selected cases increase the proportion of patients who can be offered conservative surgery. 相似文献
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167.
McCall J.C. Wipf D.P. Trivedi M.M. Rao B.D. 《Intelligent Transportation Systems, IEEE Transactions on》2007,8(3):431-440
In this paper, we demonstrate a driver intent inference system that is based on lane positional information, vehicle parameters, and driver head motion. We present robust computer vision methods for identifying and tracking freeway lanes and driver head motion. These algorithms are then applied and evaluated on real-world data that are collected in a modular intelligent vehicle test bed. Analysis of the data for lane change intent is performed using a sparse Bayesian learning methodology. Finally, the system as a whole is evaluated using a novel metric and real-world data of vehicle parameters, lane position, and driver head motion. 相似文献
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169.
RP Fule 《Canadian Metallurgical Quarterly》1997,51(7):221-225
170.