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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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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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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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Yap AU  Sau CW  Lye KW 《Operative dentistry》1999,24(6):371-376
The effect of age of a poly-acid-modified composite resin on repair bond strength after different methods of surface conditioning was studied. Surface conditioning methods included the following: maleic acid with resin application; polyacrylic acid with resin application; sand-blasting with resin application. Shear bond testing between the aged and new material was carried out with an Instron Universal Testing Machine. Although repair bonds strengths after all surface conditioning methods were significantly higher than the control group at 1 week, no statistically significant differences in bond strengths were noted after aging the material for 6 months. After all aging periods, surface conditioning with sand-blasting and resin application resulted in the highest repair bond for poly-acid-modified composite resins. Specimens with cohesive failure in the material gave significantly higher repair bond strengths than specimens with adhesive failure at the repaired interface.  相似文献   
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Acupuncturehasbeenusedforover2000years forawidevarietyofcomplaintswithminimalsideef fects.Clinicallyithasbeenobservedthatpatients havingsimilarailmentsrespondtoacupuncturethera pyinvaryingdegrees.Tofindoutthebasisofsuch variationofefficacyofacupuncturetherapy,surveyof patientswithABObloodgroupswastakenup.Inhu manbeingthechromosome9isaverypopulargene(ABOgene)thatdeterminesourbloodgroups.Link ofbloodgroupswithsomediseasesisknown,e.g.carcinomaofstomachismostfrequentlyseeninpeo plewithgroupA[1]…  相似文献   
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