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As audience reception scholars commute from audiences to literacies, both of which share the concept of interpretation, this article sets out to draw together themes around the changing nature of interpretive work, from 6 texts that have reflected recently, in different ways, on interpretation in new media environments. In reviewing a multithreaded conversation across 4 books from literacy studies, media and communications, and user studies, I select 2 essays, written at a crucial moment for reception studies, to provide her a narrative. Speaking from diverse fields, these works suggest a widespread agreement that there is a need to rethink terminologies and concepts from mass-mediated communication in the age of interactive media, not because they no longer prove useful, but because they provide constructive intellectual challenges in thinking through the changing natures of texts and readers, genres and interpretation, literacies, and legibilities, as we await new modes every day, for all of these, but also perhaps, new modes of interpretative engagement.  相似文献   
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Nicotine, responsible for the addictive properties of tobacco, is widely used in nicotine replacement therapy for tobacco use cessation. We investigated the time-dependent effect of treatment with nicotine on the tumor suppressor, DNA repair and immune responses. Swiss Albino mice (laca strain) of both sexes received nicotine dissolved at a dose of 100 µg/ml in 2% sucrose for 24 weeks, by oral gavage, while age- and gender-matched controls received only 2% sucrose for the same period. Nicotine-treated and control mice were sacrificed 6, 16 and 24 weeks post-treatment, and their tissues evaluated for alterations in histology, oxidative stress, TNF-α levels, nitric oxide (NO) and myeloperoxidase (MPO) release, tumor suppressor response and DNA repair response. Statistical significance of results was determined using Students’ t test. The tissues of nicotine treated mice exhibited a large number of multinucleated and binucleated cells, enlarged nuclei and non-uniform distribution of cells, significant increase in expression of TNF-α gene and serum TNF-α, and time-dependent significant increase in lipid peroxidation, protein carbonylation, NO and MPO release when compared to age-and gender-matched controls. The mRNA expression of the tumor suppressor gene p53, its primary regulator Mdm2, and the DNA repair genes Brca2 and Ape1 were significantly elevated, but the corresponding protein levels remained largely unaltered. In conclusion, treatment with nicotine caused oxidative stress and inflammation which can cause widespread cellular damage from the very onset of treatment, without subverting the tumor suppressor and DNA repair responses.Electronic supplementary materialThe online version of this article (10.1007/s12291-020-00903-8) contains supplementary material, which is available to authorized users.  相似文献   
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The circadian periodicity of plasma lipid peroxide levels and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were studied in 50 clinically, bacteriologically and radiologically proven fresh cases of pulmonary tuberculosis (age: 21–45 years) and 60 age-matched healthy volunteers with diurnal activity from 06∶00 to about 22∶00 and nocturnal rest. A marked circadian variation in plasma lipid peroxide level was recorded in healthy subjects and pulmonary tuberculosis patients with significant amplitude and acrophase around 16∶21 and 17∶12 respectively. The acrophase tended to be delayed in tuberculosis patients. Furthermore, a statistically significant circadian rhythm was found in SOD, CAT and GPx activities in normal volunteers and pulmonary tuberculopsis patients. SOD and CAT enzyme activity was noted to be maximum at 06∶00 and minimum at 00∶00 in tuberculosis patients. The circadian acrophase for GPx activity was recorded at 16∶15 in normals and around 22∶45 in patients. Moreover, the activity was found to be decreased at all sampling hours during 24-hours sleep-awake period in patients in comparison to healthy counterparts. The MESOR and circadian amplitude also decreased markedly. The decreased activity of measured antioxidant enzymes in pulmonary tuberculosis patients could probably be associated with oxidative stress and/or decreased anti-oxidant defensive mechanism in such patients.  相似文献   
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The present study was undertaken to evaluate antidiabetic and antioxidant activities of Cassia tora (C. tora) seeds extract against streptozotocin induced diabetes in experimental rats to scientifically validate its use against diabetes. Ethanolic extract of C. tora seeds extract and standard drug (glibenclamide) prepared in aqueous gum acacia (2 %, w/v) suspension and fed orally to streptozotocin induced male adult diabetic rats of Charles Foster strain for 15 days. Biochemical parameters in normal, diabetic control, standard (600 μg/kg bw p.o.) and treated (500 mg/kg bw p.o.) animal groups were quantified and compared. Treatment of streptozotocin induced diabetic rats with ethanolic seeds extract caused significant (p < 0.001) reduction in blood glucose (270–220 mg/dl), total cholesterol (140–104 mg/dl), triglyceride (149–99 mg/dl), phospholipids (100–74 mg/dl), free fatty acid (2.39–2.00 μmol/l), lipid peroxide (9–5.63 nmol MDA/dl) and significantly increased post heparin lipolytic activity (11–14 nmol FFA released/h/l plasma) (p < 0.001). Furthermore, the seeds extract (100–400 μg) when tested for its antioxidant activity in vitro, showed significant (p < 0.001) inhibition in the generation of super oxide anions in enzymic system a (46–37, 33, 23, 21 nmol uric acid formed/min), in enzymic system b (113–91, 77, 60, 51 nmol formazon formed/min), non-enzymic system (324–230, 211, 161, 141 nmol uric acid formed/min) and hydroxyl radicals in enzymic system (544–501, 411, 319, 291 nmol 2,3-dihydroxybenzoate formed/h) and non-enzymic system (28–21, 17, 14, 12). The results of the present study demonstrated antidiabetic, antidyslipidemic and antioxidant activities of C. tora seeds which could help in prevention of diabeticdyslipidemia and related complications.  相似文献   
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The hypolipidemic activity of Cassia tora (Chakvat, Chakunda) (Family: Caesalpiniaceae) seeds extract have been studied in two models of hyperlipidemia in rats. In an acute model, hyperlipidemia was induced by injecting a single dose of Triton WR-1339 (400 mg/kg, b.w.) intraperitonially in rats. Feeding with C. tora seed extract at the dose of 500 mg/kg, b.w. exerted significant lipid lowering effect as assessed by the reversal of plasma levels of total cholesterol, phospholipids, triglyceride and reactivation of post heparin lipolytic activity. In the chronic model, hyperlipidemia was induced by feeding with cholesterol rich-HFD in rats. The treatment with seeds extract of C. tora (500 mg/kg, b.w.) simultaneously for 15 days also caused lowering of lipid levels in plasma and liver following reactivation of plasma post heparin lipolytic activity and hepatic lipoprotein lipase activity in animals. The hypolipidemic activity of C. tora seeds was compared with a standard drug guggulipid (200 mg/kg, b.w.) in both models.  相似文献   
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Cytokines, viral load and opportunistic infections play an important role in HIV-disease progression. Hundred children vertically infected with HIV were enrolled to determine mRNA levels of TNF-α, IL-10, IL-4 and IFN-γ. These levels were estimated by amplifying cytokine mRNA from peripheral blood mononuclear cells. Severity of HIV was staged by the reduction in CD4 + T cells and the onset of opportunistic infections. IL-10 mRNA levels were observed to increase with the severity. Despite the rising IL-10 mRNA levels, TNF-α mRNA levels increased with severity of HIV and decrease in CD4 + T cell counts. IL-4 mRNA levels increased with the reduction in CD4 + T cell numbers. Depleting mRNA levels of IFN-γ contributed to the worsening of HIV disease. Increase in TNF-α and IL-4 levels appended to the disease severity by upregulation of the viral replication. Increased IL-10 levels and decreased IFN-γ levels predisposed the children to HIV associated opportunistic infections, which in return contributed to cytokine disarray.  相似文献   
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The antidyslipidemic activity of Hibiscus rosa sinensis (Malvaceae) root extract has been studied in alloxan induced diabetic rats. In this model, oral administration of root extract (500 mg/kg bw. p.o.) for 15 days resulted in significant decreased in the levels of blood glucose, plasma lipids and reactivated post heparin lipoprotein lipase activity in alloxan induced diabetic rats. Furthermore, the root extract (50–500 μg) when tested for its antioxidant activity, inhibited the generation of super oxide anions and hydroxyl radicals, in both enzymic and non enzymic systems in vitro. The results of the present study demonstrated antidyslipidemic and antioxidant activities in root extract of H. rosa sinensis which could be used in prevention of diabetic-dyslipidemia and related complications.  相似文献   
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