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31.
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Soma Gupta K. K. Singh V. J. Vyas V. N. Chaturvedi M. V. R. Reddy B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2000,15(1):52-55
Oxidative stress was studied by estimating plasma levels of malondialdehyde (MDA), beta carotene, vitamin E and erythrocytic
superoxide dismutase(E-SOD) activity in 50 cases of carcinoma of upper digestive tract which included carcinoma of oral cavity,
pharynx and oesophagus. While plasma MDA level was found to be increased (3.5±1.0 nmole/ml), a significant decrease in beta
carotene (81.2±14.5mg%), vitamin E (8.5±1.1 mg/L) level and E-SOD activity (657.0±80.6 U/G Hb) were observed in carcinoma
of upper digestive tract. Patients were treated with radiotherapy which itself was toxic enough and produced its deleterious
effects by generation of reactive oxygen species (ROS). As antioxdiants can detoxify ROS, beneficial effect if any, of antioxidant
administration during radiotherapy was studied in two groups of patients, group A (n=5, supplemented with antioxidants) and
group B (n=5, without antioxidant supplementation). Plasma MDA level was found to be elevated in both the groups but the increase
in group B was significant, compared to pretreatment level. Further, body weight was found to be significantly decreased in
group B patients, which was maintained in group A patients. Moreover, group A patients showed significant elevation in beta
carotene concentration, thus showing beneficial effect of administration of antioxidants during radiotherapy without disturbing
the desirable therapeutic effect of radiotherapy. 相似文献
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Anders Albrechtslund 《Ethics and Information Technology》2007,9(1):63-72
This article offers a discussion of the connection between technology and values and, specifically, I take a closer look at
ethically sound design. In order to bring the discussion into a concrete context, the theory of Value Sensitive Design (VSD)
will be the focus point. To illustrate my argument concerning design ethics, the discussion involves a case study of an augmented
window, designed by the VSD Research Lab, which has turned out to be a potentially surveillance-enabling technology. I call
attention to a “positivist problem” that has to do with the connection between the design context and the use context, which
VSD seems to presuppose, and I argue that it is necessary to clearly distinguish between the two, since the designers’ intentions
do not always correspond with the users’ practice; in fact, the relation between design and use is very complex and principally
unpredictable. Thus, a design theory must accept that foresight is limited to anticipation rather than prediction. To overcome
the positivist problem, I suggest a phenomenological approach to technology inspired by Don Ihde’s concept of multistability.
This argument, which is general in nature and thus applies to any theory of design ethics, is intended as a constructive criticism,
which can hopefully contribute to the further development of design ethics. 相似文献
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The purpose of this study was to describe and understand the range of outcomes of class visits to natural history museums.
The theoretical framework is based on the multifaceted process of learning in free choice learning environments, and emphasizes
the unique and individual learning experience in museum settings. The study’s significance is in highlighting several possible
cognitive as well as non-cognitive learning effects in museums class visits, by providing the student’s point of view. Data
was collected by semi-structured interviews with 50 students in grades 6–8 on the day following the visit. We present evidence
that students expressed several learning outcomes, connected directly and indirectly to the scientific content of the visit.
Content oriented outcomes included acquiring scientific knowledge and making connections to prior knowledge; social oriented
outcomes were identified in students’ statements regarding communicating knowledge and social aspects of learning; and interest
oriented outcomes were evidenced by students’ expressions about emotions, interest and curiosity. The aggregate data addressed
the common outcomes and the impact of class visits to natural history museums in the short term. Comparisons between two types
of museums show significant differences in several aspects, regarding the exhibit and/or the activity type. Practical ideas
for structuring the ultimate experience are included. 相似文献
40.
This article investigates the intertwined constructs of metacognition and self-regulation as they emerge in the works and
theories of James, Piaget, and Vygotsky. To coordinate this exploration, we use an interpretive framework based on the relation
of subject and object. In this framework, James’s perspective on metacognition and self-regulation is aligned with the Self,
Piaget’s with the other and object, and Vygotsky’s with the medium or agency of language. We explore how metacognition and
self-regulation function within the realm of human behavior and development as described in the works of each of these theorists.
Key questions or issues that emerge for current research are outlined, and the limitations and benefits of each theorist’s
perspective vis-à-vis metacognition and self-regulation are discussed. 相似文献