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31.
Atherosclerotic cardiovascular disease is the most common cause of death in the United States. Investigation of atherosclerotic plaque morphology and composition is important because the findings may be useful in predicting prognosis or response to therapy. This study presents high-resolution magnetic resonance (MR) imaging techniques developed on a 1.5-T whole-body imager with a custom-built surface coil, for characterizing the composition and morphology of plaque removed at carotid endarterectomy. The initial comparison of MR imaging and histologic results showed good correlation. In conjunction with MR angiography, these techniques could be used in in vivo imaging to define the size, location, and contents of atherosclerotic plaque at the carotid bifurcation.  相似文献   
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Prolonged hypoxia induced transient drug resistance in Chinese hamster lung fibroblasts. Previously hypoxic cells were resistant to adriamycin and resistant to etoposide. Complete recovery of etoposide sensitivity was observed following re-aeration for 24 hr. A change in P-glycoprotein expression was unlikely to contribute to the resistance caused by hypoxia, since adriamycin resistance was not reversed by verapamil. However, alteration in the plasma membrane structure may be involved, since previously hypoxic cells were resistant to extracellular superoxide radical generated by the addition of xanthine/ xanthine oxidase. In contrast, adriamycin sensitivity was not altered by hypoxia in 3 human breast-cancer cell lines. MDA-468 and MCF-7/Adr differed in their response to EGF, independent of the presence of hypoxia. These results suggest that hypoxic-stress-induced drug resistance is not generalized.  相似文献   
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A national study was conducted between 1991 and 1994 to explore and describe the changing role of the nurse teacher following the introduction of Project 2000 pre-registration nursing courses. Multiple methods were used to collect data from a wide variety of respondents (nurse teachers, midwife teachers, clinical nurses, health service managers and higher education lecturers). This paper presents the findings relating to the impact of Project 2000 and the move into higher education on the continuing educational needs of nurse teachers. Views on college strategies for staff development, the changing nature of teachers'academic and professional development needs and the problems of the conflicting demands experienced are reported. The research highlights the need for clinical credibility to be clearly defined in relation to nurse teachers and for educational institutions to place more emphasis on teachers'clinical development if the rhetoric of policy is to become a reality.  相似文献   
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Alcoholic inpatients evaluated the level of empathy demonstrated by a purported alcoholism counselor. Forty-two detoxified subjects viewed a 15-min videotape of a simulated alcoholism counseling session. Subjects had been randomly assigned to one of two groups: Group 1 was told that the counselor they were about to see was a recovering alcoholic whose empathy they were to evaluate. The subjects in Group 2 were given the same instructions; however, the information concerning the counselor's drinking history was omitted. A form of the Barrett-Lennard Relationship Inventory (BLRI) was administered immediately after the viewing. No statistical differences between group means on the empathy subscale of the BLRI were found. This finding does not support the contention that a history of drinking and rehabilitation enhances the perception of counselor empathy among alcoholics.  相似文献   
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