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11.
J. I. Anetor F I Ajose T. S Akingbola 《Indian journal of clinical biochemistry : IJCB》2005,20(1):193-197
A 64-year-old security guard and longstanding known hypertensive presented with hypertensive heart disease (HHD), weight loss,
an enlarged prostate, and a spontaneously fractured rib. Malignancy of the prostate with possible metastases to the ribs was
strongly suspected. Biochemical profiling revealed a paraprotein. Other biochemical and hematological correlates that were
on hand before serum protein electrophoresis were rather atypical. Paraprotein studies by immunofixation revealed IgA myelomatosis.
Unlike previous reports from Caucasians there was normocalcaemia, normal protein level, microcytic hypochromia, low MCHC,
cholesterol level at the lower limit of the reference range and normal urea level (in the face of markedly raised creatinine
level). Nutritional modulation of the classical laboratory features of this disease may account for the fairly atypical laboratory
picture.
The need to appreciate the influence of nutritional status on the laboratory (especially biochemical) features of a disease
and thus interpretation of diagnostic tests appears of exceptional current importance, given the widening gap in socioeconomic
status and the level of poverty between the resource poor and developed countries from which the classical, clinical and laboratory
features of most diseases were first described.
This case report reminds of the need not only to recognize theoretically the impact of nutritional status on the laboratory
characteristics of a disease but of the practical application of the nutritional perspective in the interpretation of diagnostic
investigations, especially in nutritionally disadvantaged communities. 相似文献
12.
This paper presents a classifier for text data samples consisting of main text and additional components, such as Web pages and technical papers. We focus on multiclass and single-labeled text classification problems and design the classifier based on a hybrid composed of probabilistic generative and discriminative approaches. Our formulation considers individual component generative models and constructs the classifier by combining these trained models based on the maximum entropy principle. We use naive Bayes models as the component generative models for the main text and additional components such as titles, links, and authors, so that we can apply our formulation to document and Web page classification problems. Our experimental results for four test collections confirmed that our hybrid approach effectively combined main text and additional components and thus improved classification performance. 相似文献
13.
To become competent professionals, students should work on both their strengths and weaknesses. Considering students' limited amount of time and energy to work on multiple subjects, it is important to know what determines their allocation of effort to their perceived relative strengths or weaknesses. In a series of five studies, we examined the moderating effect of instructional strategy (i.e., self-directed versus test-directed) on the within-person relation between perceived relative strength (i.e., strengths versus weaknesses) and allocated effort across multiple subjects. We used different methodologies (scenario, field, and experimental studies), research designs (within-person and mixed factorial), populations (secondary school, college, and university students), and measures of effort (intentions, self-reported, and behavioral). The results consistently indicate that students in a self-directed instructional strategy condition tend to allocate more effort to their relative strengths, whereas students in a test-directed instructional strategy condition tend to allocate more effort to their relative weaknesses. 相似文献
14.
形成性评价是开放教育教学过程质量控制的一个重要途径。从开放教育课程学习目标,即知识性学习目标、学习能力目标和情感性目标出发,构建了多元形成性评价指标体系、管理运行机制及系统架构。并根据多元形成性评价系统架构,设计了题库和作业库结构,提出了基于六维约束的自动组卷算法。针对真实数据集进行的大量实验表明,该算法具有较高的效率,从而为多元形成性评价系统的成功应用奠定了基础。随着互联网的飞速发展,社会性评价、发展性评价以及个性化、智能化评价将是形成性评价的发展方向。 相似文献
15.
Continued advancement in the field of physical activity and health promotion relies heavily on the synthesis of rigorous scientific evidence. As such, systematic reviews and meta-analyses of randomized controlled trials have led to a better understanding of which intervention strategies are superior (i.e., produce the greatest effects) in physical activity-based health behavior change interventions. Indeed, standard meta-analytic approaches have allowed researchers in the field to synthesize relevant experimental evidence using pairwise procedures that produce reliable estimates of the homogeneity, magnitude, and potential biases in the observed effects. However, pairwise meta-analytic procedures are only capable to discerning differences in effects between a select intervention strategy and a select comparison or control condition. In order to maximize the impact of physical activity interventions on health-related outcomes, it is necessary to establish evidence concerning the comparative efficacy of all relevant physical activity intervention strategies. The development of network meta-analysis (NMA)—most commonly used in medical-based clinical trials—has allowed for the quantification of indirect comparisons, even in the absence of direct, head-to-head trials. Thus, it stands to reason that NMA can be applied in physical activity and health promotion research to identify the best intervention strategies. Given that this analysis technique is novel and largely unexplored in the field of physical activity and health promotion, care must be taken in its application to ensure reliable estimates and discernment of the effect sizes among interventions. Therefore, the purpose of this review is to comment on the potential application and importance of NMA in the field of physical activity and health promotion, describe how to properly and effectively apply this technique, and suggest important considerations for its appropriate application in this field. In this paper, overviews of the foundations of NMA and commonly used approaches for conducting NMA are provided, followed by assumptions related to NMA, opportunities and challenges in NMA, and a step-by-step example of developing and conducting an NMA. 相似文献
16.
17.
陈琼 《衡阳师范学院学报》2008,29(6)
基于奇异值分解理论的数字水印技术是一种新的值得探讨和研究的变换域水印技术,它的提出为数字水印技术的发展开拓了新的思路和方法.本文对传统的基于奇异值分解理论的数字水印技术进行了深入分析和研究,并提出了改进方法,给出了一种新的基于奇异值分解的数字水印方案.仿真实验证明,新的方法比较好的满足了数字水印的透明性和鲁棒性,能经受住通常的图像处理操作且具有较大的应用潜力. 相似文献
18.
本文基于文本数字水印的特征编码思想,通过设置Word文档中字符的下划线格式以嵌入和检测水印。实验表明,该算法有较强的不可见性,能较好的嵌入和检测水印,从而达到数字水印的一般要求。 相似文献
19.
马在《诗经》中的具有多重涵义。《诗经》中常以马喻人,特别是君子贤人,有时还用马来代指财富和战争。 相似文献
20.
【】本文根据2004年-2013年《高等学校科技统计资料汇编》的相关数据对政府科技投入以及高校创新产出进行了相关研究。本文首先将全国高校按照学校类型进行分类,并依据此对其政府科技投入以及高校创新产出进行了定性分析以及实证分析。实证结果显示无论是利用总量数据、人均数据还是增长率数据发现高校的政府科技投入与高校创新产出在呈现出正相关性关系外,也同时存在一定的滞后性,且对于不同类型高校来说,其边际效益以及滞后性都存在一定差异。最后,本文根据研究结果提出了对相关政策的建议。 相似文献