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991.
Free iron in serum has been found in several disease conditions including diabetes. In the present work, we studied the relationship between free iron, fasting blood glucose (FBG) and glycated haemoglobin (HbA1c). Study was carried out on 50 type 2 diabetes cases under poor glycemic control associated with complications, 53 type 2 diabetes cases under good glycemic control and 40 healthy controls. We estimated free iron, both ferrous (Fe+2) and ferric (Fe+3) form, protein thiols, lipid hydroperoxides, FBG, HbA1c and serum ferritin levels in serum. There was a significant increase in free iron in Fe+3 state (p <0.01), HbA1c (p<0.01), serum ferritin (p<0.01), lipid hydroperoxides (p<0.01) and significant decrease in protein thiols (<0.01) in diabetes cases under poor glycemic control compared to diabetes cases under good glycemic control and healthy controls. Free iron correlated positively with HbA1c (p<0.01). Poor glycemic control and increase in glycation of haemoglobin is contributing to the increase in free iron pool which is known to increase oxidant generation.  相似文献   
992.
This paper provides an in-depth analysis of the privacy rights dilemma surrounding radio frequency identification (RFID) technology. As one example of ubiquitous information system, RFID has multitudinous applications in various industries and businesses across society. The use of this technology will have to lead to a policy setting dilemma in that a balance between individuals’ privacy concerns and the benefits that they derive from it must be drawn. After describing the basic RFID technology some of its most prevalent uses, a definition of privacy is derived in the context of information systems. To illustrate current attempts at controlling the undesirable side effects of RFID, Lessig’s cyberspace framework is presented. It is found that each of Lessig’s components is inadequate at preventing individual privacy violations in RFID. The main focus within this framework is on the norms of society. The social norm mechanism that addresses privacy issues in cyberspace is the Fair Information Practices Principles (FIPP). After an analysis of these principles, it is posited that the FIPP only deal with procedural justice issues related to data collection and omit distributive and interactional justice reasoning related to the actual beneficial and detrimental outcomes to the individuals whose data is being obtained. Thus, RFID is presented in the context of the tension between the many benefits that are provided by the technology in social exchanges, and the risk it carries of the loss of privacy. The new, expanded framework recognizes both sides of the issue with the ultimate goal of providing a greater understanding of how privacy issues can be addressed with RFID technology.  相似文献   
993.
994.
Premature coronary artery disease (CAD) is common in India. We, therefore, studied oxidative stress, dyslipidemia, and high sensitivity-C reactive protein (hs-CRP) levels in young CAD patients. Present study consisted of male CAD patients below 40 years and age and sex matched healthy controls (n=30 each). Fasting blood samples were analyzed for serum lipid profile, malondialdehyde, antioxidant enzymes and hs-CRP levels. Dyslipidemia was observed in 90% of the young CAD patients, of which 72.2% showed increased serum triglycerides and decreased HDL-cholesterol. LDL-cholesterol levels were high in 77.8%. Serum malondialdehyde and hs-CRP levels were increased significantly (p<0.0001) as compared to controls. hs-CRP levels were in high risk range in all the young patients. However, glutathione peroxidase activity was reduced significantly (p<0.05). Our data suggests that elevated hs-CRP levels along with dyslipidemia and oxidative stress adds to the predictive value of premature CAD in young Indians.  相似文献   
995.
HER-2 is overexpressed in approximately 20–30% of invasive Breast Cancer. ECD of the HER-2 protein is frequently cleaved and released into the circulation, where it can be detected by ELISA in up to 45% of patients with metastatic breast cancer. The objective of our study was to compare the current methods for the detection of HER-2 protein. Tissue HER-2 levels were studied in 100 breast cancer patients by IHC and compared with serum HER-2 levels by ELISA. IHC frequency was 29%. Serum HER-2 ECD was positive in 42% of patients. A statistically significant correlation was observed. HER-2 detected by IHC correlates significantly with serum HER-2 levels detected by ELISA. Thus, ELISA is a reliable and economical tool to assess the HER-2 status in tumors, when breast tissue sample is not available.  相似文献   
996.
In recent decades, changes in society have deeply affected the internal organization and the main goals of schools. These changes are particularly important in science education because science is one of the major sources of change in peoples’ lives. This research provided the opportunity to investigate how these changes affect the way teachers develop their classroom activities. In this work, we focus on science as part of the cultural identity of a society and how this identity affects the process of teaching and learning inside the classroom. Other works have shown that certain social characteristics such as gender, race, religion, etc., can create a cultural barrier to learning science. This results in an obstacle between those particular students and the science that is taught, hindering their learning process. We first aim to present the notion of identity in education and in other related fields such as social psychology and sociology. Our main purpose is to focus on identity in a school setting and how that identity affects the relationship students have with the science content. Next, we present and analyze an intervention in the subject of Modern and Contemporary Physics composed by a sequence of activities in a private school in the region of Sao Paulo State, Brazil. This intervention serves to illustrate how scientific topics may be explored while considering aspects of cultural differences as an obstacle. The intervention was completed in two steps: first, in the classroom with a discussion concerning scientific works and nationality of scientists, with one being a Brazilian physicist; second, taking students to visit a particle collider at the University of São Paulo. One of the results of our research was realizing that students do not perceive science as something representative of the Brazilian cultural identity. At the same time, the activity gave the students the opportunity to make the connection between doing physical sciences at an international level and the national level in Brazil. The findings of this study suggest that it is possible to reshape the cultural identity of Brazilian students.  相似文献   
997.
998.
999.
Social media challenge knowledge management because of encouraging conversations, networking and participation in more distributed, diverse and dynamic ways of knowledge development and increasingly important individuals’ interests driving them. Hence, we need to understand the complex relationships between different qualities of knowledge developed in informal and formal processes as well as for overcoming misalignments in routines, tools and infrastructures supporting organizational knowledge creation. This paper contributes a maturation perspective towards explaining organizational knowledge creation and presents a knowledge maturing model, which is grounded in organizational practice and validated with qualitative and quantitative empirical and design studies. The results describe how characteristics of knowledge and support by IT change between phases of knowledge maturing. Our findings confirm theories of organizational knowledge creation with respect to expanding scopes from individuals through communities to organizations moving from interest-driven knowledge exploration in informal contexts to goal-driven knowledge exploitation in formal contexts. The maturation perspective adds to our understanding that organizational knowledge creation is not simply a continuous process. Phases that emphasize changeability alternate with phases concerned with stability. Knowledge develops in contexts that need to switch multiple times between opening up for new knowledge and filtering relevant knowledge and between de- and re-contextualization.  相似文献   
1000.
This paper presents an approach aimed at creating business ontologies for knowledge codification in company. It is based on the principles of ontological engineering and cognitive psychology. Ontologies that describe the main concepts of knowledge are used both for knowledge creation and codification. The proposed framework is targeted at the development of methodologies that can scaffold the process of knowledge structuring and orchestrating for better understanding and knowledge sharing. The orchestrating procedure is the kernel of ontology development. The main stress is put on using visual techniques of mind mapping. Cognitive bias and some results of Gestalt psychology are highlighted as a general guideline. The ideas of balance, clarity, and beauty are applied to the ontology orchestrating procedures. The examples are taken mainly from the project management practice. The paper contributes to managerial practice by describing the practical recommendations for effective knowledge management based on ontology engineering and knowledge structuring techniques.  相似文献   
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