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1.
根据信息传递中我们需要准确可靠的信息这种实际情况,利用双向S-粗集理论提出了一种动态粗传递模型,即双向S-下近似动态粗传递模型.分析了该模型的特性,得到了信息保持不变、信息发生损失与知识的关系,给出了提高信息传递精确性的方法以及该模型的应用.  相似文献   
2.
More than wisdom     
This paper presents and interprets empirical findings from field studies in a Bambara village in the Republic of Mali in order to place the traditional position of the elderly in cultural context. The significance of a seniority principle underlying the social structure of African society is emphasized. Thus attitude and behavioral changes which affect the status of the elderly have wider ramifications for the society as a whole. Attention centers on the role of age sets, myth and ritual, ancestor worship and socialization practices as elements of a total cultural system in which the rules of seniority provide an organizing force. In the last section, the ways in which social change threatens the viability of a social system governed by the seniority principle are reviewed. Signs of breaks in the solidarity of the traditional community are noted. Finally, two strategies for improving the position of the elderly in the African countryside as the traditional system disintegrates are proposed.To the people of Sonongo in gratitude.  相似文献   
3.
目的:为眼部热力及化学性烧伤导致的睑球粘连寻找一种新的治疗方法。方法:用残留的结膜行1次或多次后退重建结膜囊。结果:1998年以来用此法为38例(40只眼)睑球粘连者进行了治疗,其中13例(13只眼)行2次,19例(21只眼)行3次,仅6例(6只眼)行1次结膜后退成功,其中1例失败。结论:结膜后退法是矫治睑球粘连的一些种有效的方法。  相似文献   
4.
The reversal learning capacity of young rhesus monkeys in visual discrimination tasks was examined during daily exposure to dietary lead acetate throughout the first year of life. While not affected in physical development, all lead-treated monkeys showed performance deficits on reversal learning tasks. These deficits were independent of lead-induced changes in motivation. Over a series of problems, the overall learning rate of monkeys with blood lead concentrations in the range of 70-90 microgram/dl was retarded, which resulted partly from a pronounced difficulty in attaining criterion on the first of a series of reversals within a given problem. This latter deficit resulted from an increase in errors, balks, and total trials to criterion on the first reversal. Monkeys exposed to blood lead concentrations of 40-60 microgram/dl required significantly more trials to finish all problems, but did not show the first-reversal deficit. Theoretical implications of these data were discussed.  相似文献   
5.
分析了某些一次性使用输液(血)器中部分化学性能测定结果重现性差并常常引起不合格的原因,提出生产工艺改进的建议.  相似文献   
6.
郑小霞  钱锋 《医学教育探索》2006,(12):1458-1462
提出一种基于变精度粗糙-模糊集模型的诊断知识获取算法,利用相似性聚类方法自动获取模糊隶属函数,将连续属性表示成模糊值,通过定义模糊相似关系和模糊相似类给出了变精度粗糙-模糊模型的近似表示,并引入蚁群算法求取模糊相似关系下的属性约简,进行诊断知识的获取。将其应用于精对苯二甲酸生产过程尾氧浓度故障诊断知识获取中,结果表明:该算法可以从故障数据中提取更客观有效的诊断规则,在实际故障诊断中具有很好的应用价值。  相似文献   
7.
Abstract

Objective: To identify relevant aspects of functioning, disability, and contextual factors for adults with hearing loss (HL) from hearing health professional perspective summarized using the ICF classification as reference tool. Design: Internet-based cross-sectional survey using open-ended questions. Responses were analysed using a simplified content analysis approach to link concept to ICF categories according to linking rules. Study sample: Hearing health professionals (experts) recruited through e-mail distribution lists of professional organizations and personal networks of ICF core set for hearing loss steering committee members. Stratified sampling according to profession and world region enhanced the international and professional representation. Results: Sixty-three experts constituted the stratified sample used in the analysis. A total of 1726 meaningful concepts were identified in this study, resulting in 209 distinctive ICF categories, with 106 mentioned by 5% or more of respondents. Most categories in the activities & participation component related to communication, while the most frequent environmental factors related to the physical environment such as hearing aids or noise. Mental functions, such as confidence or emotional functions were also frequently highlighted. Conclusions: More than half (53.3%) of the entire ICF classification categories were included in the expert survey results. This emphasizes the importance of a multidimensional tool, such as the ICF, for assessing persons with hearing loss.  相似文献   
8.
Canine breast cancer was considered as an ideal model of comparative oncology for the human breast cancer, as there is significant overlap between biological and clinical characteristics of the human and canine breast cancer. We attempt to clarify expression profile of the embryonic stem cell (ES) gene signatures in canine breast cancer. Using microarray datasets (GSE22516 and GSE20718), expression of the three major ES gene signatures (modules or gene‐sets), including Myc, ESC‐like, and PRC modules, was primarily analyzed through Gene‐Set Enrichment Analysis (GSEA) method in tumor and healthy datasets. For confirmation of the primary results, an additional 13 ES gene‐sets which were categorized into four groups including ES expressed (ES exp1 and ES exp2), NOS targets (Nanog targets, Oct4 targets, Sox2 targets, NOS targets, and NOS TFs), Polycomb targets (Suz12 targets, Eed targets, H3K27 bound, and PRC2 targets), and Myc targets (Myc targets1, and Myc targets2) were tested in the tumor and healthy datasets. Our results revealed that there is a valuable overlap between canine and human breast cancer ES gene‐sets expression profile, where Myc and ESC‐like modules were up‐regulated and PRC module was down‐regulated in metastatic canine mammary gland tumors. Further analysis of the secondary gene‐sets indicated overexpression of the ES expressed, NOS targets (Nanog targets, Oct4 targets, Sox2 targets, and NOS targets), and Myc targets and underexpression of the Polycomb targets in metastatic canine breast cancer.  相似文献   
9.
目的:研制一种新型多功能面套,应用于颅颌面创伤患者,以达到快速、简便、通用、舒适、牢固和安全的对患者进行包扎.方法:42例患者包括额部、颏部、人中、面颊部、头顶部损伤及合并伤,使用颅颌面创伤多功能面套对其进行包扎治疗.结果:颅颌面创伤多功能面套对42例患者均一次性包扎成功,且提高了包扎的效果.结论:该多功能面套可快速、简便、通用、舒适、牢固和安全的对患者进行包扎,是一种新型的颅颌面创伤包扎面套.  相似文献   
10.
Introduction: Activity landscapes (ALs) are graphical representations that integrate compound structure and potency relationships. These computer-generated models enable the interactive large-scale analysis of structure–activity relationships (SARs) and complement traditional approaches to study SARs of individual compound series in a qualitative or quantitative manner. A variety of AL designs have been reported.

Areas covered: The concept of activity landscapes is introduced and different methodologies to represent 2D or 3D AL representations of large compound data sets are described on the basis of original literature references. Several AL variants and extensions have been generated for special applications in medicinal chemistry. These include, for example, AL views of evolving data sets with constant topology, selectivity landscapes and multi-target ALs, or molecular mechanism and multi-property maps. Furthermore, the applicability domain of the AL concept is discussed including specific requirements for practical utility in medicinal chemistry opportunities for further developments.

Expert opinion: AL modeling has substantially extended conventional ways to study SARs. The AL concept is inseparable from the notion of activity cliffs that are of high interest in SAR analysis. AL design is an area of active research at the interface between chemoinformatics and medicinal chemistry with potential for further growth. Special emphasis must be put on increasing the usability of AL models for practicing medicinal chemists.  相似文献   
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