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101.
K. Pratibha Usha Anand Rajni Agarwal 《Indian journal of clinical biochemistry : IJCB》2004,19(2):128-131
Serum adenosine deaminase (ADA), 5′ nucleotidase (5′NT) and malondialdehyde (MDA) were estimated in patients with acute infective
hepatitis (AIH) along with the routine parameters of liver disease. Present study is done to evaluate these special parameters
in patients with clinical history of AIH and to assess the utility of these parameters as diagnostic/ prognostic indices of
liver function and to correlate special parameters with routine live function tests (LFT). ADA, 5′NT and MDA along with routine
LFT was estimated in 25 patients with AIH and 25 samples from healthy voluntary blood donars served as the control group.
Routine LFT was estimated by standard clinical chemistry procedures on dade behring analyser and ADA, 5′NT and MDA were estimated
by berthlot reaction, fiske and subbarao method and thiobarbituric acid method respectively.
Statistical analysis showed that serum ADA, 5′NT and MDA were significantly higher in patients as compared with the controls.
There was a significant positive correlation between ADA and total bilirubin and MDA and total bilirubin. Hence we can conclude
that these tests would be more sensitive to diagnose the patients with AIH and that the raised bilirubin levels could be looked
upon, as a protective mechanism which the liver has evolved in order to combat oxidative stress. 相似文献
102.
Amanda Jarrell Jason M. Harley Susanne Lajoie Laura Naismith 《Educational technology research and development : ETR & D》2017,65(5):1263-1284
Students experience a variety of emotions following achievement outcomes which stand to influence how they learn and perform in academic settings. However, little is known about the link between student outcome emotions and dimensions of performance feedback in computer-based learning environments (CBLEs). Understanding the dynamics of this relationship is particularly important for high-stakes, competency-based domains such as medical education. In this study, we examined the relationship between medical students’ (N = 30) outcome emotion profiles and their performance on a diagnostic reasoning task in the CBLE, BioWorld. We found that participants could be organized into distinct emotion groups using k-means cluster analyses based on their self-reported outcome emotion profiles: an expected positive emotion cluster and negative emotion cluster and an unexpected low intensity emotion cluster. A clear relationship was found between emotion clusters and diagnostic performance such that participants classified to the positive emotion cluster had the highest performance; those classified to the negative emotion cluster had the lowest performance; and those classified to the low intensity emotion cluster had performance outcomes that fell between the other two. Our discussion focuses on the theoretical implications of emotion classification and design recommendations for learning environments and emotional interventions in computer-based contexts. 相似文献
103.
Xue-fen Yang Yue-qin Qiu Li Wang Kai-guo Gao Zong-yong Jiang 《Journal of Zhejiang University. Science. B》2018,19(11):884-894
Because of their physiological similarity to humans, pigs provide an excellent model for the study of obesity. This study evaluated diet-induced adiposity in genetically lean pigs and found that body weight and energy intake did not differ between controls and pigs fed the high-fat (HF) diet for three months. However, fat mass percentage, adipocyte size, concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), insulin, and leptin in plasma were significantly higher in HF pigs than in controls. The HF diet increased the expression in backfat tissue of genes responsible for cholesterol synthesis such as Insig-1 and Insig-2. Lipid metabolism-related genes including sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthase 1 (FASN1), diacylglycerol O-acyltransferase 2 (DGAT2), and fatty acid binding protein 4 (FABP4) were significantly up-regulated in backfat tissue, while the expression of proliferator-activated receptor-α (PPAR-α) and carnitine palmitoyl transferase 2 (CPT2), both involved in fatty acid oxidation, was reduced. In liver tissue, HF feeding significantly elevated the expression of SREBP-1c, FASN1, DGAT2, and hepatocyte nuclear factor-4α (HNF-4α) mRNAs. Microarray analysis further showed that the HF diet had a significant effect on the expression of 576 genes. Among these, 108 genes were related to 21 pathways, with 20 genes involved in adiposity deposition and 26 related to immune response. Our results suggest that an HF diet can induce genetically lean pigs into obesity with body fat mass expansion and adipose-related inflammation. 相似文献
104.
Reinforced concrete (RC) columns lacking adequately detailed transverse reinforcement do not possess the necessary ductility to dissipate seismic energy during a major earthquake without severe strength degradation. In this paper, a new retrofit method, which utilized fiber-reinforced plastics (FRP) confinement mechanism and anchorage of embedded bars, was developed aiming to retrofit non-ductile large RC rectangular columns to prevent the damage of the plastic hinges. Carbon FRP (CFRP) sheets and glass FRP (GFRP) bars were used in this test, and five scaled RC columns were tested to examine the function of this new method for improving the ductility of columns. Responses of columns were examined before and after being retrofitted. Test results indicate that this new composite method can be very effective to improve the anti-seismic behavior of non-ductile RC columns compared with normal CFRP sheets retrofitted column. 相似文献
105.
Kodjo Attikpoé 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2007,53(1):23-37
YOUTH LITERATURE IN THE CONTEXT OF PEDAGOGIC AND LITERARY NORMS: THE FRENCH-SPEAKING COUNTRIES OF AFRICA – There are two approaches to children’s and youth literature, one didactic, the other aesthetic. This gives rise to the following question: taking into account the fact that children’s literature aspires to be a literary form in its own right, should more weight be attibuted to its aesthetic value when evaluating it? This paper examines this question – which has in the past been the subject of highly controversial discussions in the German-speaking regions – by focusing on youth literature in the French-speaking coutries of Africa. The pedagogic dimension cannot be ignored when considering this literary context because it is so much a part of the post-colonial dynamic. Youth literature in the French-speaking countries of Africa echoes current realities. Examples are used to demonstrate how literature can deal with vital questions without neglecting the literary aspect. 相似文献
106.
107.
Researchers have long debated the meaning of mathematical understanding and ways to achieve mathematical understanding. This study investigated experienced Chinese mathematics teachers’ views about mathematical understanding. It was found that these mathematics teachers embrace the view that understanding is a web of connections, which is a result of continuous connection making. However, in contrast to the popular view which separates understanding into conceptual and procedural, Chinese teachers prefer to view understanding in terms of concepts and procedures. They place more stress on the process of concept development, which is viewed as a source of students’ failures in transfer. To achieve mathematical understanding, the Chinese teachers emphasize strategies such as reinventing a concept, verbalizing a concept, and using examples and comparisons for analogical reasoning. These findings draw on the perspective of classroom practitioners to inform the long-debated issue of the meaning of mathematical understanding and ways to achieve mathematical understanding. 相似文献
108.
Peter Danielson 《Ethics and Information Technology》2010,12(3):251-261
We can learn about human ethics from machines. We discuss the design of a working machine for making ethical decisions, the
N-Reasons platform, applied to the ethics of robots. This N-Reasons platform builds on web based surveys and experiments,
to enable participants to make better ethical decisions. Their decisions are better than our existing surveys in three ways.
First, they are social decisions supported by reasons. Second, these results are based on weaker premises, as no exogenous
expertise (aside from that provided by the participants) is needed to seed the survey. Third, N-Reasons is designed to support
experiments so we can learn how to improve the platform. We sketch experimental results that show the platform is a success
as well as pointing to ways it can be improved. 相似文献
109.
P-selectin, a cell adhesion molecule is elevated in many inflammatory conditions including preeclampsia which is characterized
by generalized endothelial dysfunction and vasoconstriction presumably due to free radicals or mediators released by defective
placentation. Vitamin E has been documented to protect cell membranes from oxidative damage and also decrease platelet aggregation.
The role of vitamin E in pre-eclampsia is contradictory and hence the study was undertaken. Soluble P-selectin was measured
by ELISA and Vitamin-E levels in plasma was estimated spectrofluorometrically. In our study the effect of supplementation
of 400 IU/day of Vitamin E (a-tocopheryl acetate) to patients of pre-eclampsia showed significant decreased levels of soluble
P-selectin by 2nd week as compared to patients given placebo (P = 0.005). In this short period of study no direct correlations were observed between Vitamin E or P-selectin levels with
blood pressure as well as with proteinuria. Future studies may focus on the effect of a-tocopheryl acetate or the phosphate
form of Vitamin-E, recently proposed to be the more active form on other inflammatory markers like IL-6, an important stimuli
of P-selectin release in pre-eclampsia. 相似文献
110.
Participation,financial support and the marginal student 总被引:2,自引:0,他引:2
This paper examines differences between the decision-making of marginal and nonmarginal students about participation in higher
education (HE). We distinguish between two kinds of marginality: being ‘borderline’ on account of prior achievements in school
and being ‘unsure’ after taking prior achievement into account. We identify a significant minority of students in their final
year of schooling who are unsure about participation in higher education even though they have prior school achievements typical
of entrants to HE. Being ‘unsure’ is found to be unrelated to socioeconomic background, but it is associated with significantly
different attitudes towards the potential benefits and risks of participation, different levels of knowledge about financial
support that is available and different approaches to information search about participation in HE.
相似文献
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