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11.
Abstract  Preference utilitarians are concerned to maximize the autonomous choices of individuals; for this reason, they argue that nurses ought to advocate for those patients who desire assistance with ending their lives. This approach prompts us to consider, then, the moral validity of nursing involvement in measures intended to end the lives of patients. In this article, the terms of preference utilitarianism are set out and considered in order to determine whether this approach offers sufficient philosophical support for sanctioning a role for nursing in euthanasia. Ultimately, it is found that preference utilitarianism is lacking in this respect, as well as in its fitness for guiding nursing activity in general. In particular, it is found that nurses are required to exchange a handmaiden relationship with the medical profession for an equally undignified relationship with patients. If nursing involvement in measures intended to end the lives of patients is to find sufficient philosophical support, then we need to look elsewhere.  相似文献   
12.
本文对160名有正常生育力的男性精液标本同时进行了精子尾部低渗肿胀率(HOS)、精子头部DNA荧光染色的有效精子计数(ESC)、前向运动精子百分率(PMS)、活动精子百分率(MS)的检测,分析它们之间的一致性。结果发现:HOS与PMS或MS间的符合率分别为74%与88%;ESC与PMS或MS间的符合率分别为63%与66%;ESC与HOS间的符合率为67%。提示HOS或ESC可从不同角度去反映被测精子的生育力。  相似文献   
13.
The present paper reports on the inaugural meeting of the Mental Health Special Interest Research Group (SIRG) of the International Association for the Scientific study of Intellectual disability which was held at Fitzwilliam College, Cambridge, UK, in March 1998. The meeting was organized in conjunction with the Ninth Annual SIRG on ageing and intellectual disability. Representatives from North America, several European and Scandinavian countries, Australia, and Israel attended. Two broad themes had been determined prior to the meeting: ‘Improving the detection of mental health problems’ and ‘Research strategies for identifying risk factors for mental health problems’. In the presentations and subsequent discussions, it was apparent that there were extrenely diverse perspectives both across and within the different countries represented. Not only were individuals' experiences very different, but most strikingly, the theoretical frameworks were very diverse. This was partly a function of there being understandable differences in perspectives across disciplines, but at its most marked, there were fundamental differences in the way both intellectual disability and mental health were conceptualized.  相似文献   
14.
BACKGROUND: Sperm DNA integrity (SDI) is an important factor in the prognosis of male fertility. Here we compare the toluidine blue (TB) image cytometry test, recently proposed by us for SDI assessment, with two other tests-the sperm chromatin structure assay (SCSA) and the terminal nick-end labelling (TUNEL) assay. METHODS: Sperm samples from 35 men were evaluated for standard sperm parameters and subjected to the TB test and SCSA. Eighteen of the 35 samples were also subjected to the TUNEL assay. RESULTS: The proportion of sperm cells with abnormal DNA integrity assayed by the TB test correlated strongly with the proportion of abnormal cells detected by the SCSA and TUNEL assay (rho=-0.84 and rho=0.80, P<0.001, respectively). Furthermore, the fractions of abnormal cells by the TB test corresponded closely to the sum of two SCSA parameters, the DNA fragmentation index (DFI) and the fraction of highly DNA-stainable cells (HDS) (medians 33.0 versus 32.0%, P=0.6). CONCLUSIONS: Abnormal cells in a TB test correspond to the sum of DFI and HDS fractions in the SCSA. TB-positive cells may represent sperm with fragmented DNA and/or abnormal chromatin structure. Because the TB test is an easy and inexpensive method, its potential use as a routine test for sperm DNA integrity, complementary to standard semen parameters, should be investigated further.  相似文献   
15.
Perepletchikova and Kazdin's (this issue) analysis of the treatment integrity literature should guide future research and practice on this vital issue facing clinical research and practice. This commentary considers the construct of treatment integrity and those factors that moderate the relationship between treatment integrity and treatment outcome. Specifically, this paper examines the three components of treatment integrity specified by Perepletchikova and Kazdin (treatment adherence, therapist competence, treatment differentiation), the relationship between treatment integrity and treatment outcome, and measurement and validation issues involving treatment integrity.  相似文献   
16.

Introduction

The usage of formalin-fixed paraffin embedded (FFPE) tissue is characterized by its long shelf-life and simple handling. Therefore it is the most commonly available tissue specimen in routine diagnostics and histological studies. Formaldehyde fixation may result in RNA degradation and cross linking with proteins, while storage conditions also affect RNA integrity. The present study was designed to investigate the influence of these factors on RNA analysis.

Design

FFPE-derived RNA from sections of 23 patients with spontaneous pneumothoraxes was used. Unstained sections of FFPE tissue were stored at various temperatures (?80?°C, ?20?°C, 4?°C, 24?°C) prior to RNA extraction. The potential impact on RNA quality of semi-automatic and manual RNA isolation and three different deparaffinization agents (mineral oil, xylene and d-limonene) were compared.

Results

The storage temperature of FFPE sections affects RNA concentration and fragmentation, with the optimal storage temperature below -20?°C. The RNA extracted with d-limonene shows equivalent quality to the RNA extracted using more toxic standard agents. The manual isolation provides a higher RNA yield compared to the semi-automatic isolation. However, no differences in the amount of longer RNA fragments were observed. Furthermore, the semi-automatic isolation showed an enhanced RNA quality.

Conclusion

FFPE sections not directly used for RNA extraction should be stored below -20?°C to increase quality and yield of the RNA. Usage of semi-automatic isolation produces superior results and simplifies routine processes by having less hands-on-time. Replacement of toxic xylene by d-limonene may contribute to improved occupational safety while not influencing analytical results.  相似文献   
17.
The naive Bayes model makes the often unrealistic assumption that the feature variables are mutually independent given the class variable. We interpret a violation of this assumption as an indication of the presence of latent variables, and we show how latent variables can be detected. Latent variable discovery is interesting, especially for medical applications, because it can lead to a better understanding of application domains. It can also improve classification accuracy and boost user confidence in classification models.  相似文献   
18.
【目的】 介绍《国家科学评论》(National Science Review,NSR)的办刊实践,以期促进我国英文科技期刊办刊经验的交流。【方法】 以NSR为研究对象,结合办刊特色及发展实践,探讨建设高水平期刊的策略与举措。【结果】 NSR在重要研究成果组约和发表、访谈和论坛举办、学术质量控制、学术影响提升等方面开展了大量卓有成效的工作,有效地提高了期刊的品牌声誉,较好地服务了学术传播与交流。【结论】 NSR初步实现了全方位、多角度反映中外自然科学研究重要成就的定位和目标,学术指标和影响力得到快速提升,其办刊实践可为我国科技期刊的高质量发展提供参考与借鉴。  相似文献   
19.
【目的】 对我国学术期刊关联数据出版与共享中的信息安全管理的概念、政策及其存在的问题进行梳理,有助于科学数据出版与共享工作的推进。【方法】 基于我国科学数据出版与共享的演化过程,以及地理资源期刊在科学数据共享方面的现状与发展情况,对期刊论文关联数据出版和安全管理情况进行分析,对平台间合作的模式进行探讨。【结果】 为实现科学数据的价值最大化,中国自上而下建立起了科学数据共享系统,包括网络基础设施、数据库、数据中心、数据服务平台等,制定了一系列数据获取和管理规范,并制定了保障科学数据信息安全的相关法律。【结论】 科学数据出版与共享应建立在安全的基础上。经过初期的大规模建设后,数据出版与共享及其安全管理应走向“提质增效”阶段,要注重高新技术的注入和专业人才的培养。在管理措施上要以保证数据安全为基础,以数据质量为核心,从而提升信息安全管理水平,提高数据再应用效率。  相似文献   
20.
【目的】 总结科技期刊封面设计流程管理模式并探讨其中的相关问题,为同行提供经验借鉴。【方法】 从版面、设计风格等方面对科技期刊封面图片的特征进行归纳。以中国激光杂志社期刊封面为例,总结封面设计流程管理模式,探讨封面设计过程中的相关问题。【结果】 期刊应对封面的主题策划、生产流程、版权保护等方面进行有效的流程管理。此外,就封面设置及风格、元素文化、版权意识、与设计公司合作等问题进行思考总结。【结论】 科技期刊可通过合理的封面设计流程,将科技与艺术融合,更准确地传播前沿科技成果,并弘扬中国传统文化。  相似文献   
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