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Background: Tyrosine protein kinase proteins exert a prominent control on signaling pathways and may couple rapid events, such as action potential and neurotransmitter release, to long-lasting changes in synaptic strength and survival. Whether anesthetics modulate tyrosine kinase activity remains unknown. The aim of the current study was therefore to examine the effects of intravenous and volatile anesthetics on the phosphorylation of focal adhesion kinase (pp125FAK), a functionally important nonreceptor tyrosine kinase, in the rat hippocampus.

Methods: Phosphorylation of pp125FAK was examined in hippocampal slices by immunoblotting with both antiphosphotyrosine and specific anti-pp125FAK antibodies. Experiments were performed in the absence (control) or presence of various concentrations of pharmacologic or anesthetic agents or both.

Results: Clinically relevant concentrations of thiopental, propofol, etomidate, isoflurane, sevoflurane, and desflurane induced a concentration-related increase in tyrosine phosphorylation. In contrast, ketamine (up to 100 [mu]m) and the nonimmobilizer F6 (1,2-dichlorohexafluorocyclobutane, 25 [mu]m) did not significantly affect pp125FAK phosphorylation. The anesthetic-induced increase in pp125FAK phosphorylation was blocked by GF 109203X, RO 318220, and chelerythrin (100 [mu]m), three structurally distinct inhibitors of protein kinase C and U 73122 (50 [mu]m), an inhibitor of phospholipase C. The propofol- and isoflurane-induced increase in pp125FAK phosphorylation was reversible and showed nonadditivity of effects with phorbol 12-myristate 13-acetate (an activator of protein kinase C, 0.1 [mu]m). In contrast, ketamine (up to 100 [mu]m), MK801 (10 [mu]m, an N-methyl-d-aspartate receptor antagonist), bicuculline (10 [mu]m, a [gamma]-aminobutyric acid type A receptor antagonist), and dantrolene (30 [mu]m, an inhibitor of the ryanodine receptor) were ineffective in blocking anesthetic-induced activation of tyrosine phosphorylation.  相似文献   

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Subtraction and conventional radiography were evaluated for their diagnostic potential to assess interradicular bone lesions in the mandibular premolar region. Both conventional radiographs and subtraction images were interpreted by 10 observers. The receiver-operating characteristic (ROC) technique was used to compare the two techniques. The diagnostic validity was higher for the subtraction technique, both for lesions confined to cancellous bone and for lesions including the cortical bone, than for the conventional technique. For bone defects confined to cancellous bone the diagnostic accuracy was lower than those reported from periapical bone lesions irrespective of whether subtraction or conventional radiography was used. We conclude that subtraction radiography improves the detectability of bone lesions, shallow ones in particular. Lesions in the interradicular bone are more difficult to detect than those in the periapical bone.  相似文献   
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Caring for a child in a body cast is a stressful situation for most families and many families state they do not receive adequate information on how to care for their child. This paper presents a comprehensive guide on caring for a child in a body cast. It examines the physical care issues, transportation and cast care. An instrument for assessing the family’s ability to cope with caring for a child in a body cast is described, and further resources for parents and nurses are presented.  相似文献   
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A multiple Robertsonian fission chromosomal race of the Liolaemus monticola complex in Chile is described and is shown to be the most derived and the most complex among the Liolaemus examined thus far. The 29 karyotyped lizards analysed from the locality of Mina Hierro Viejo, Petorca, Provincia de ValparaUso, Chile, exhibited a diploid chromosomal number ranging from 42 to 44, and several polymorphisms. The polymorphisms included: a pair 1 fission; a pair 2 fission plus a pericentric inversion in one of the fission products, which moved the NOR and satellite from the tip of the long arm of the metacentric 2 to the short arm of the fission product; a fission in pair 3; a polymorphism for an enlarged chromosome pair 6; and a polymorphism for a pericentric inversion in pair 7. This population is fixed for a fission of chromosome pair 4. A total of 76% of the lizards analysed were polymorphic for one or more pairs of chromosomes. We have compared these data with other Liolaemus monticola chromosomal races and calculated the Hardy–Weinberg ratios for the polymorphic chromosome pairs in this Multiple-Fission race. Karyotypic differences between the Northern (2n = 38–40) and the Multiple-Fission (2n = 42–44) races were attributed mainly to Robertsonian fissions, an enlarged chromosome and pericentric inversions involving the macrochromosomes and one microchromosome pair.  相似文献   
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