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Survivin is a multitasking protein that can inhibit cell death and that is essential for mitosis. Due to these prosurvival activities and the correlation of its expression with tumor resistance to conventional cancer treatments, survivin has received much attention as a potential oncotherapeutic target. Nevertheless, many questions regarding its exact role at the molecular level remain to be elucidated. In this study we ask whether the extreme C- and NH2 termini of survivin are required for it to carry out its cytoprotective and mitotic duties. When assayed for their ability to act as a cytoprotectant, both survivin1–120 and survivin11–142 were able to protect cells against TRAIL-mediated apoptosis, but when challenged with irradiation cells expressing survivin11–142 had no survival advantage. During mitosis, however, removing the NH2 terminal 10 amino acids (survivin11–142) had no apparent effect but truncating 22 amino acids from the C-terminus (survivin1–120) prevented survivin from transferring to the midzone microtubules during anaphase. Collectively the data herein presented suggest that the C-terminus is required for cell division, and that the NH2 terminus is dispensable for apoptosis and mitosis but required for protection from irradiation.  相似文献   
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Treatment of rats with mirex (40 ppm in diet) caused hypoglycemia, liver enlargement, and inhibition of adrenal corticosteroid-synthesizing enzyme activity. At toxic dosages (20,000 ppm mirex in diet, which has a lethal toxicity-50 [LT-50] of ten days) poisoned female rats showed severe hypoglycemia, fatty liver, adrenal hyperplasia, hypophagia, lipid mobilization, and body weight (bw) loss. A 50 μg/kg intraperitoneal (IP) dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in male rats caused similar effects two days posttreatment. Hypoglycemia could be overcome by prednisone (which also inhibited adrenocorticoid-synthesizing enzyme activities) but not by streptozotocin treatment, indicating that hypoglycemia may be related to glucocorticoid deficiency resulting from inhibition of their synthesis and not by direct effects on pancreatic β-cells. Glucocorticoid deficiency could also cause increased release of adrenocorticoid hormone (ACTH), which may enhance fat mobilization caused by hypophagia.  相似文献   
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Summary In ethanol production with immobilized yeast a major problem is the provision of nutrients to these highly concentrated cells. O2 being one of the nutrients of utmost importance to yeast cells, was fed into a column packed with beads with a cell loading of more than 40 g/l. Since addition of large volume of air or O2 to a cylindrical column reactor would aggravate the problems of pressure build up and channelling caused by the evolving CO2 gas, a tapered-column reactor and pulsed flow of oxygen gas was used. The supplement of O2 gas to the tapered column increased the productivity from 21.1 g ethanol x (l gel x h)-1 to 26.7 g x (l gel x h)-1, when the ethanol concentration at the outlet was about 80 g/l. The yield coefficient of ethanol was also increased from 0.41 g ethanol/g glucose to 0.43 after O2 supplement was started. The effects of frequency and duration of O2 supplement were also determined.  相似文献   
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The new urban social order depends on a complex combination of systems of punishment, discipline, and security. Scholars drawing on Foucault's analysis of the art and rationality of governance, or govemmentality, have explored how urban social orders are increasingly based on the governance of space rather than on the discipline of offenders or the punishment of offenses. The new urban social order is characterized by privatized security systems and consumer-policed spaces such as malls. Gender violence interventions represent another deployment of spatial forms of govemmentality. Over the last two decades, punishment of batterers has been augmented by disciplinary systems that teach batterers new forms of masculinity and by security systems for women based on spatial separation. In the postmodern city, spatial govemmentality is integrally connected with punishment and discipline. These new forms of governance circulate globally along with neoliberal ideas of the diminished state, [gender violence, govemmentality, urban society, globalization, law]  相似文献   
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