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A Garg  R Buckman  Y Kason 《CMAJ》1997,156(8):1159-1164
PROGRAM OBJECTIVE: To teach medical students to break bad news to patients and their families empathically and competently. SETTING: Seven teaching hospitals affiliated with the University of Toronto since 1987. PARTICIPANTS: All medical students in their third preclinical year. PROGRAM: The course presents a 6-point protocol to guide students in breaking bad news and comprises 2 half-day (3-hour) teaching sessions. Each session incorporates a video presentation, a discussion period and small-group teaching, consisting of exercises followed by 4 different role-playing scenarios conducted with the use of standardized patients. The course was evaluated through 2 questionnaires, 1 administered before and 1 after the course, which measured changes in the students'' attitude and strategy. Questionnaires were administered during 5 of the years since the course was started. A total of 914 precourse and 503 postcourse questionnaires were completed, of which 359 matched pairs of precourse and postcourse questionnaires were analysed to study any changes due to the course. OUTCOMES: Precourse questionnaires showed that 68% of the students had thought about the task of breaking bad news often or very often. Of the 56% of students who had seen clinicians performing this task, 75% felt that they had seen good examples. The proportion of the students who had a plan for how to conduct such an interview rose from 49% before the course to 92% after it, and the proportion who felt they might be reasonably competent in breaking bad news rose from 23% before the course to 74% after it. CONCLUSIONS: The subject of breaking bad news is important to medical students, and it is practicable to design a course to teach the basic techniques involved. Most students perceive such a course as enjoyable and useful and find that it increases their sense of competence and their ability to formulate a strategy for such situations.  相似文献   
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Foraminifera have one of the best known fossil records among the unicellular eukaryotes. However, the origin and phylogenetic relationships of the extant foraminiferal lineages are poorly understood. To test the current paleontological hypotheses on evolution of foraminifera, we sequenced about 1,000 base pairs from the 3' end of the small subunit rRNA gene (SSU rDNA) in 22 species representing all major taxonomic groups. Phylogenies were derived using neighbor- joining, maximum-parsimony, and maximum-likelihood methods. All analyses confirm the monophyletic origin of foraminifera. Evolutionary relationships within foraminifera inferred from rDNA sequences, however, depend on the method of tree building and on the choice of analyzed sites. In particular, the position of planktonic foraminifera shows important variations. We have shown that these changes result from the extremely high rate of rDNA evolution in this group. By comparing the number of substitutions with the divergence times inferred from the fossil record, we have estimated that the rate of rDNA evolution in planktonic foraminifera is 50 to 100 times faster than in some benthic foraminifera. The use of the maximum-likelihood method and limitation of analyzed sites to the most conserved parts of the SSU rRNA molecule render molecular and paleontological data generally congruent.   相似文献   
24.

Background  

Most studies examining the commensal human oral microbiome are focused on disease or are limited in methodology. In order to diagnose and treat diseases at an early and reversible stage an in-depth definition of health is indispensible. The aim of this study therefore was to define the healthy oral microbiome using recent advances in sequencing technology (454 pyrosequencing).  相似文献   
25.

Background  

The past several years have seen a flurry of papers seeking to clarify the utility and limits of DNA barcoding, particularly in areas such as species discovery and paralogy due to nuclear pseudogenes. Heteroplasmy, the coexistence of multiple mitochondrial haplotypes in a single organism, has been cited as a potentially serious problem for DNA barcoding but its effect on identification accuracy has not been tested. In addition, few studies of barcoding have tested a large group of closely-related species with a well-established morphological taxonomy. In this study we examine both of these issues, by densely sampling the Hawaiian Hylaeus bee radiation.  相似文献   
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Platelet activation is tightly regulated by products of the endothelium and platelets including nitric oxide (NO). Excess vascular oxidative stress has been associated with impaired NO release, and antioxidant status has been shown to alter endothelium-derived NO bioactivity. Although physiological levels of a-tocopherol are known to inhibit platelet function, the effect of a-tocopherol on platelet NO release is unknown. Loading platelets with physiologic levels of a-tocopherol increased platelet NO production approximately 1.5-fold (Pa-tocopherol, platelet NO release increased 50% (Pa-Tocopherol-loaded platelets also produced 74% less superoxide as compared with control (Pa-tocopherol inhibited PKC-dependent eNOS phosphorylation as determined by immunoprecipitation. Lastly, platelets isolated from NOS3-deficient mice released 80% less superoxide as compared with control animals (P=0.011), and incubation of NOS III-deficient platelets with 500 mM a-tocopherol only caused a modest additional decrease in platelet superoxide release (NS). Thus, a-tocopherol appears to enhance platelet NO release both in vitro and in vivo through antioxidant- and PKC-dependent mechanisms.  相似文献   
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We report here the design and synthesis of a novel series of benzylamines that are potent and selective inhibitors of uPA with promising oral availability in rat. Further evaluation of one representative (ZK824859) of the new structural class showed that this compound lowered clinical scores when dosed in either acute or chronic mouse EAE models, suggesting that uPA inhibitors of this type could be useful for the treatment of multiple sclerosis.  相似文献   
29.
Analysis of copia sequence variation within and between Drosophila species   总被引:1,自引:0,他引:1  
The sequences of the 5' long-terminal repeat (LTR) and adjacent leader regions of 27 full-length copia elements isolated from natural populations of Drosophila melanogaster, D. simulans, and D. mauritiana are presented. Phylogenetic analyses indicate that although D. melanogaster copia elements are distinct from those of D. simulans and D. mauritiana, the elements of these latter two species are not distinguishable from one another. LTRs and adjacent 5' leader regions of elements isolated from D. simulans and D. mauritiana are structurally similar to one another and carry substantial deletional variation mapping to regions previously identified as being of potential importance for copia expression.   相似文献   
30.
We examine rate heterogeneity among evolutionary lineages of the grass family at two plasmid loci, ndhF and rbcL, and we introduce a method to determine whether patterns of rate heterogeneity are correlated between loci. We show both that rates of synonymous evolution are heterogeneous among grass lineages and that are heterogeneity is correlated between loci at synonymous sites. At nonsynonymous sites, the pattern of rate heterogeneity is not correlated between loci, primarily due to an aberrant pattern of rate heterogeneity at nonsynonymous sites of rbcL. We compare patterns of synonymous rate heterogeneity to predictors based on the generation time effect and the speciation rate hypotheses. Although there is some evidence for generation time effects, neither generation time effects nor speciation rates appear to be sufficient to explain patterns of rate heterogeneity in the grass plastid sequences.   相似文献   
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