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排序方式: 共有810条查询结果,搜索用时 15 毫秒
1.
Patricia Lye Charlotte Heidenreich Rebekah Wang-Cheng Dawn Bragg Deborah Simpson 《Ambulatory Pediatrics》2003,3(2):93-97
OBJECTIVES: To determine if experienced clinical educators (CEs) can improve their teaching by incorporating 4 literature-based teaching methods into their instruction. METHODS: We trained 7 experienced CEs on the teaching methods during a monthly faculty development program. Each CE recorded use of these methods during 10 months on a personal digital assistant. We compared the CEs' teaching evaluations with those of nonparticipating faculty by analysis of variance at baseline, during the study period, and for 1 year after the study. RESULTS: Reported use of 2 teaching methods (priming and feedback) increased significantly over use at baseline; use of 2 other methods (teaching in the patient's presence and 1-2 focal teaching points) remained constant. Scores on the CEs' teaching evaluations were significantly higher during the study period on 1 item, whereas the comparison group showed no changes. The changes persisted during the follow-up period. CEs reported that the teaching methods focused the learner and teacher, making subsequent encounters more productive. They also found that the act of entering data daily prompted them to reflect on their teaching. CONCLUSIONS: Experienced teachers can be persuaded to incorporate new methods into their daily teaching. Reflection on teaching is enhanced with group support and daily reminders. With these interventions, teaching effectiveness of these experienced educators improved. 相似文献
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Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
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E. T. Whalley Y. O. Amure R. H. Lye 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(4):433-437
Summary Bradykinin (BK) initially produced concentration-related relaxations of human basilar artery in vitro. Concentration-effect curves constructed at 2 h intervals to BK over an 8 h period were reproducible. The rank order of potency of three kinins on the human basilar artery was found to be BK > methionyl-lysyl-BK > des-Arg9-BK. The B2-receptor antagonist Thi5,8
d-Phe7-BK but not the B1-receptor antagonist des-Arg9-Leu8-BK selectively blocked BK-induced relaxations of the human basilar artery.The relaxant effects of bradykinin and acetylcholine but not papaverine were attenuated after removal of the endothelium or treating the tissues with BW755C. Indomethacin was without effect. Concentration-effect curves to angiotensin I were markedly attenuated by captopril at a concentration which had no effect on BK, angiotensin II or 5-hydroxytryptamine responses. It is concluded that BK induced relaxations of the human basilar artery are mediated via activation of a B2 receptor and the response is dependent upon the release of a factor present in the endothelium. Angiotensin converting enzyme is present in the human basilar artery and is important for the conversion of angiotensin I to angiotensin II but apparently not for the degradation of BK. It is likely that other kininases are present and active in the tissue.
Send offprint requests to E. T. Whalley at the above address 相似文献
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Anti-angiogenic effects of Hypericin-photodynamic therapy in combination with Celebrex in the treatment of human nasopharyngeal carcinoma 总被引:4,自引:0,他引:4
Photodynamic therapy (PDT) is being investigated as an alternative treatment modality in cancer treatment. It has been shown to induce tumor hypoxia and upregulation of cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF). The objective of this study was to improve in vivo tumor growth control of nasopharyngeal carcinoma (NPC), treated at a subcurative dosage by using a combination of Hypericin-PDT and COX-2 inhibitor, Celebrex (CX). The effect of an initial CX dose at 6- and 24-h post-PDT was investigated simultaneously. It was observed that hypoxic NPC/CNE2 cells upregulate both COX-2 and VEGF A genes in vitro. In vivo studies, down-regulation of COX-2 and hypoxia inducible factor-1alpha (HIF-1alpha) genes at 24-h post-PDT and bulk tumor ablation at 48-h post-PDT was observed. However, 24-28 days later regrowth was observed. In a combination treatment, 1st CX dose at 6-h post-PDT had the highest tumor control in which tumors were 相似文献
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Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献
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