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31.
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RATIONALE AND OBJECTIVES: Effective communication is essential for high quality care, yet little is known about radiologists' communication with patients, what constitutes "best communication practices," and how best to teach and evaluate it. We piloted educational strategies and an assessment instrument to teach and evaluate radiologists' communication skills. We focused on communication in the diagnostic mammography suite, where patient-radiologist interactions are often intense and stressful. MATERIALS AND METHODS: We adapted existing instruments to create a Radiology Communication Skills Assessment Tool (RCSAT). We piloted an educational program that included patients as teachers and raters of interpersonal and communication skills, and implemented a radiology objective structured clinical examination (OSCE). We measured radiology residents' self-assessed skills, confidence and stress, as well as patient-rated communication skills using the RCSAT. RESULTS: Residents' baseline self-assessed communication skills regarding abnormal mammograms were fair, confidence in their communication was minimal, and they found this communication stressful. Overall baseline communication skills, rated by patient-teachers using the RCSAT, were 3.62 on a 5-point scale (1 = poor to 5 = excellent). Analysis of post-OSCE debriefing comments yielded nine themes regarding effective radiology communication, as well as residents' reflections on the communication challenges they experience. The themes were integrated into subsequent RCSAT revisions. Residents' reflections were used to inform teaching workshops. CONCLUSION: Educational curricula on communication about difficult information can be implemented in radiology training programs. Radiology residents' performance can be assessed using a communication skills assessment tool during standardized patient-teacher encounters. Further research is necessary in this important domain.  相似文献   
33.
阿克拉霉素A聚氰基丙烯酸异丁酯毫微粒的冻干针剂,能明显抑制体外培养人肝癌细胞株7703的生长,IC50为0.28μg·ml-1。在0.8μg·ml-1浓度时,克隆形成抑制率为90%,抑制作用有明显剂量依赖关系而未见明显时间依赖关系。静脉给药后,对常位移植人肝癌模型裸小鼠的抑瘤率为86.84%,肿瘤细胞增殖活性阳性率为20.83%。体内外均显示明显的抗肝癌活性,且体内抗肝癌活性比阿克拉霉素A冻干针剂强。  相似文献   
34.
The differentiation state of CD8+ T cells has emerged as a crucial determinant of their ability to respond to tumor and infection. Signals from T-cell receptors, co-stimulatory molecules and cytokine receptors direct the differentiation process. These signals 'program' sustained and heritable gene expression patterns that govern progressive differentiation and lineage commitment. The epigenetic mechanisms by which T cells are programmed are just beginning to be elucidated. Understanding the mechanisms that control CD8+ T-cell differentiation is important in the development of novel immunotherapy strategies.  相似文献   
35.
Aim: Findings of hypoxia prior to death and involvement of a dysregulation of the serotonergic network in sudden infant death syndrome (SIDS) may indicate that brain‐derived neutrophic factor (BDNF) also is of importance with regard to sudden unexpected infant death. Based on this, the purpose of this study was to investigate the BDNF val66met polymorphism in SIDS cases, cases of infectious death and controls. Methods: The polymorphism was investigated in 163 SIDS cases, 34 cases of infectious death and 121 controls, using real‐time PCR and fluorescence melting curve analysis. Results: There were no differences in val66met genotype distribution between neither the SIDS cases nor the cases of infectious death and controls (p = 0.95 and p = 0.52, respectively). Conclusion: The study indicates that the val66met polymorphism is not important for sudden unexpected infant death. However, several other SNPs in the BDNF gene, as well as in other genes involved in this pathway, including G‐protein, have to be investigated to fully exclude any involvement of BDNF in SIDS.  相似文献   
36.
37.
Abstract

There are many useful medical treatment devices today, which are indispensable in health care. However, in some emergency situations and in prehospital care mobile, easy-to-use devices could further improve the patient-centred care. For example, a mobile, easy-to-use home-monitoring EEG-system would be useful for monitoring diseases like epilepsy and for treating diseases like attention deficit disorder (ADHD) using biofeedback. Such a device should be equipped with the ability to start self-performed by user recordings and provide high signal quality, while having an affordable price. Here, we used in-ear-EEG technology and state of the art electronic components to develop such a system. This paper presents a portable, all-in-one EEG-system, capable to record biosignals on the external ear. An amplifier was developed with ADS1299 and optimised to be coupled with a smartphone. The system has a low price and at the same time provides high signal quality, has very effective common-mode-rejection, performs a fast cold start and shows low power consumptions which ensures a long time of operation. The system is easy to use and could be self-mounted and controlled by unskilled users as well. Results of test measurements are compared to a conventional EEG-System and show comparable records results quality.  相似文献   
38.
The goal of this study was to apply temperature-mediated heteroduplex analysis using denaturing high-performance liquid chromatography to identify pyrazinamide (PZA) resistance in Mycobacterium tuberculosis isolates and simultaneously differentiate between M. tuberculosis and Mycobacterium bovis. Features that contributed to an optimal assay included the use of two different reference probes for the pncA gene targets from wild-type M. tuberculosis and wild-type M. bovis, optimization of the column temperature, increasing the starting concentration of the elution buffer, and reducing the rate of elution buffer increase (slope). A total of 69 strains were studied, including 48 wild-type M. tuberculosis strains (13 were PZA-resistant strains) and 21 M. bovis strains (8 were BCG strains). In all isolates tested, wild-type M. tuberculosis generated a single-peak pattern when mixed with the M. tuberculosis probe and a double-peak pattern with the M. bovis probe. In contrast, all M. bovis isolates generated a double-peak pattern when mixed with the M. tuberculosis probe and a single-peak pattern with the M. bovis probe. PZA-resistant mutant M. tuberculosis isolates generated characteristic patterns that were easily distinguishable from both wild-type M. tuberculosis and M. bovis isolates. Chromatographic patterns generated by the two reference probes allowed the rapid detection of PZA resistance with the simultaneous ability to distinguish between M. tuberculosis and M. bovis. This approach may allow the detection of drug resistance-associated mutations, with potential application to clinical and epidemiological aspects of tuberculosis control.  相似文献   
39.
Purpose

To define the effect of sperm agglutination, associated with incubation under capacitating conditions, on accuracy of membrane assessment via flow cytometry and to develop methods to mitigate that effect.

Methods

Sperm motility was measured by CASA. Sperm were stained with PI-PSA or a novel method, LD-PSA, using fixable live/dead stain and cell dissociation treatment, before flow-cytometric analysis. Using LD-PSA, acrosome reaction and plasma membrane status were determined in equine sperm treated with 10 μm A23187 for 10 min, followed by 0, 1, or 2 h incubation in capacitating conditions.

Results

Using PI-PSA, measured membrane integrity (MI; live sperm) was dramatically lower than was total motility (TMOT), indicating spurious results (“zombie sperm”). Sperm aggregates were largely of motile sperm. Loss of motility after A23187 treatment was associated with disaggregation and increased MI. On disaggregation using LD-PSA, MI rose, and MI then corresponded with TMOT. In equine sperm incubated after A23187 treatment, as the percentage of live acrosome-reacted sperm increased, TMOT decreased to near 0.

Conclusion

Flow cytometry assesses only individualized sperm; thus, agglutination of viable sperm alters recorded membrane integrity. As viable sperm become immotile, they individualize; therefore, factors that decrease motility, such as A23187, result in increased measured MI. Disaggregation before assessment allows more accurate determination of sperm membrane status; in this case we documented a mismatch between motility and live acrosome-reacted equine sperm that may relate to the poor repeatability of A23187 treatment for equine IVF. These findings are of profound value to future studies on sperm capacitation.

  相似文献   
40.
Infection of BALB/c mice with Listeria monocytogenes stimulates an antilisterial immune response evident by the appearance of H2-Kd-restricted CD8+ cytotoxic T lymphocytes (CTLs) specific for the nanomer peptides amino acids (aa) 91 to 99 of listeriolysin O (LLO 91–99) and aa 217 to 225 of the p60 molecule (p60 217–225). We have introduced point mutations at anchor residues within LLO 91–99 (92F) or p60 217–225 (218F), and BALB/c mice infected with L. monocytogenes strains containing these point mutations do not develop CTLs specific for LLO 91–99 or p60 217–225, respectively. We have used these strains to test whether primary CTL responses against L. monocytogenes-derived determinants can be stimulated within an environment of existing antilisterial immunity. We found that the development of a primary L. monocytogenes-specific CTL response is not altered by existing immunity to L. monocytogenes. For example, primary immunization with the p60 218F strain of L. monocytogenes followed by a secondary immunization with wild-type L. monocytogenes results in stimulation of p60 217–225-specific CTLs at primary response levels and LLO 91–99-specific effectors at levels consistent with a memory CTL response. Similarly, primary immunization with the 92F strain of L. monocytogenes followed by a secondary immunization with wild-type L. monocytogenes results in stimulation of LLO 91–99-specific CTLs at primary response levels and p60 217–225-specific effectors at levels consistent with a memory CTL response. These results provide additional support for the use of L. monocytogenes as a recombinant vaccine vector and show that antivector immunity does not inhibit the development of a primary CTL response when the epitope is delivered by L. monocytogenes as the vaccine strain.  相似文献   
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