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991.
Munzir M. E. Ahmed J. A. S. Al-Obosi H. M. Osman M. E. Shayoub 《Indian journal of clinical biochemistry : IJCB》2016,31(2):162-170
Acetaminophen (APAP) a commonly used drug for decrease the fever and pain but is capable to induced hepatotoxicity at over dose. This study was carried out to investigate the effect of APAP on the expression of anti-apoptotic and antioxidative defense genes, and whether aldose reductase over-expressing plasmid capable to protect against APAP-induced oxidative stress and cell death. APAP treatment induced oxidative stress and hepatotoxicity, and significantly increased aldose reductase mRNA and protein expression in mouse hepatocyte (AML-12). Unexpectedly, AML-12 cells over-expressing aldose reductase augmented APAP-induced reduction in cell viability, reactive oxygen species (ROS) production, glutathione (GSH) depletion and glutathione S-transferase A2 expression. Moreover, over-expression of aldose reductase potentiated APAP induced reduction on proliferating cell nuclear antigen, B cell lymphoma-extra large (bcl-xL), catalase, glutathione peroxidase-1 (GPx-1) and abolished APAP-induced B-cell lymphoma 2 (bcl-2) inductions. Further, over-expression of aldose reductase significantly abolished AMP activated protein kinase (AMPK) activity in APAP-treated cells and induced p53 expression. This results demonstrate that APAP induced toxicity in AML-12, increased aldose reductase expression, and over-expression of aldose reductase render this cell more susceptible to APAP induced oxidative stress and cell death, this probably due to inhibition AMPK or bcl-2 activity, or may due to competition between aldose reductase and glutathione reductase for NADPH. 相似文献
992.
993.
Globalization has contributed to the dismantling of national boundaries, which have enabled firms to compete and conduct business on a wider scale [Held, D., McGrew, A., Goldblatt, D., & Perraton, J. (1999). Global transformations. Politics, economics and culture. Cambridge: Polity Press]. Firms can move freely between different markets using Internet-based technology. While access to such markets can provide firms with greater choice of suppliers and cost efficiencies, they need to be aware of challenges that can influence their business performance. With this in mind, we examine how these factors influenced Alcoa Alumina's drive to a global procurement platform through a global marketplace. The staged adoption process experienced at Alcoa Alumina offers a learning opportunity for other firms considering the transition to global marketplace. 相似文献
994.
Yogita S. Raut Uma S. Bhartiya Purushottam Kand Rohini W. Hawaldar Ramesh V. Asopa Lebana J. Joseph MGR Rajan 《Indian journal of clinical biochemistry : IJCB》2016,31(1):99-103
The aim was to study the genotoxic effect of high concentration of thyroxine (T4) in vivo in peripheral blood lymphocytes (PBL) of the patients suffering from thyroid disorders. The effect was compared by performing in vitro experiments with addition of increasing concentration of T4 (0.125–1 µM) in whole blood samples from healthy donors. Cytokinesis-blocked micronuclei (CBMN) assay method was used to assess the DNA damage in the PBL. The study included 104 patients which were grouped as control (n = 49), hyperthyroid (n = 31) and hypothyroid (n = 24). A significant increase in micronuclei (MN) frequency was observed in hyperthyroid patients when compared with the hypothyroid and euthyroid group thereby suggesting increased genotoxicity in hyperthyroidism (p < 0.001). A significant increase in MN frequency was observed at T4 concentration of 0.5 µM and above when compared to lower T4 concentrations (0.125 and 0.25 µM) and basal in in vitro experiments (p = 0.000). The results indicate that the T4 in normal concentration does not exhibit the genotoxic effect, as observed in both the in vivo and in vitro experiments. The toxicity of T4 increases at and above 0.5 μM concentration in vitro. Therefore acute T4 overdose should be handled promptly and effectively so as to avoid the possible genotoxic effect of high concentration of T4 in vivo. 相似文献
995.
Akila V. Prashant H. Harishchandra Vivian D'souza Benedicta D'souza 《Indian journal of clinical biochemistry : IJCB》2007,22(1):131-134
Advanced age is associated with an accumulation of free radical damage, which leads to physiological and clinical modifications.
Age related changes resulting from free radical reactions include increasing levels of lipid peroxides, alterations in enzyme
activities and greater osmotic fragility. The present study was conducted to estimate the level of lipid peroxidation product-Malondialdehyde
and antioxidants Catalase and Glutathione in elderly people. An increase in lipid peroxidation and decrease in antioxidants
was observed in normal elderly people. Highly significant increase in MDA and decrease in antioxidants was observed in elderly
people when complicated with diabetes and hypertension. Supplementation of antioxidants may prevent further oxidative injury
in elderly people. 相似文献
996.
997.
Bhupendra Pal Singh Shailendra Dwivedi Urmila Dhakad Ramesh Chandra Murthy Vimal Kumar Choubey Apul Goel Satya Narayan Sankhwar 《Indian journal of clinical biochemistry : IJCB》2016,31(1):50-56
Deficiency or excess of certain trace elements has been considered as risk factor for prostate cancer. This study was aimed to detect differential changes and mutual correlations of selected trace elements in prostate cancer tissue versus benign prostatic hyperplasia tissue. Zinc, copper, iron, calcium and selenium were analysed in histologically proven 15 prostate cancer tissues and 15 benign prostatic hyperplasia tissues using atomic absorption spectrophotometer. Unpaired two tailed t test/Mann–Whitney U test and Pearson correlation coefficient were used to compare the level of trace elements, elemental ratios and their interrelations. As compared to benign prostatic tissue, malignant prostatic tissue had significantly lower selenium (p = 0.038) and zinc (p = 0.043) concentrations, a lower zinc/iron ratio (p = 0.04) and positive correlation of selenium with zinc (r = 0.71, p = 0.02) and iron (r = 0.76, p = 0.009). Considerably divergent interrelationship of elements and elemental ratios in prostate cancer versus benign prostatic hyperplasia was noted. Understanding of differential elemental changes and their interdependence may be useful in defining the complex metabolic alterations in prostate carcinogenesis with potential for development of element based newer diagnostic, preventive and therapeutic strategies. Further studies may be needed to elucidate this complex relationship between trace elements and prostate carcinogenesis. 相似文献
998.
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
999.
We explore a financial returns dimension of the exploration-exploitation dilemma. Using 1277 R&D announcements by 178 listed bio-pharmaceutical firms, we examine whether investors are myopic along the continuum of exploration (patenting and preclinical trials) to exploitation (human clinical trials and NDA). We find that investors respond positively at every stage, but there are differences between small and large firms. For small firms exploration is favored, provided it is focused. For large firms, there is value in both exploration and exploitation. Projects which are part of an alliance are no more likely to generate abnormal returns. Policy implications are discussed. 相似文献
1000.