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71.
Paracetamol (PCM) overdose can cause nephrotoxicity with oxidative stress as one of the possible mechanisms mediating the event. In this study, the effects of ethyl acetate extract of Zingiber zerumbet rhizome [200 mg per kg of body weight (mg/kg) and 400 mg/kg] on PCM-induced nephrotoxicity were examined. Rats were divided into five groups containing 10 rats each. The control group received distilled water while other groups were treated with extract alone (400 mg/kg), PCM alone (750 mg/kg), 750 mg/kg PCM+200 mg/kg extract (PCM+ 200-extract), and 750 mg/kg PCM+400 mg/kg extract (PCM+400-extract), respectively, for seven consecutive days. The Z. zerumbet extract was given intraperitoneally concurrent with oral administration of PCM. Treatment with Z. zerumbet extract at doses of 200 and 400 mg/kg prevented the PCM-induced nephrotoxicity and oxidative impairments of the kidney, as evidenced by a significantly reduced (P<0.05) level of plasma creatinine, plasma and renal malondialdehyde (MDA), plasma protein carbonyl, and renal advanced oxidation protein product (AOPP). Furthermore, both doses were also able to induce a significant increment (P<0.05) of plasma and renal levels of glutathione (GSH) and plasma superoxide dismutase (SOD) activity. The nephroprotective effects of Z. zerumbet extract were confirmed by a reduced intensity of renal cellular damage, as evidenced by histological findings. Moreover, Z. zerumbet extract administered at 400 mg/kg was found to show greater protective effects than that at 200 mg/kg. In conclusion, ethyl acetate extract of Z. zerumbet rhizome has a protective role against PCM-induced nephrotoxicity and the process is probably mediated through its antioxidant properties.  相似文献   
72.
The effects of environmental tobacco smoke (ETS) are less studied especially on neonates. This study evaluates the clinical and biochemical effects in neonates exposed to ETS during pregnancy. Two hundred pregnant women asked to complete the questioners about their ETS. Ninety from them were enrolled in biochemical assays as two groups according to ETS. The cotinine level determined in saliva and serum of mothers to confirm their tobacco exposure. The routine tracheal suction from the fetus was used to determine the level of neuron specific enolase (NSE), soluble E-cadherin, sApo-1/Fas, nitric oxide (NO) and cotinine. In clinical assessment, the percent of full term babies in non-exposed group (72 %) are higher compared to exposed group (67 %). Apgar score at the first min, admission to intensive care unit (ICU) and morbidity during the first month shows statistical significance increase in exposed compared to non-exposed group (p = 0.03, 0.05, 0.01, respectively). The new born weight in exposed group significantly decreased compared to non-exposed group (2,850 g ± 3.74 vs 2,967.67 g ± 3.34; p = 0.02). In biochemical assessment, NSE and sE-cadherin significantly increased, while NO significantly decreased (p = 0.000) in exposed compared to non-exposed group. There is a positive correlation between level of cotinine and both NSE, sE-cadherin (r = 0.7, 0.9; p = 0.000, 0.006, respectively). To our knowledge, this is the first study link between prenatal tobacco exposure (PTE) and biochemical parameters measured in tracheal suction. PTE will lead to decrease in birth weight most probably by decreasing NO, sFas, and increasing sE-cadherin. While, increased morbidity of neonates in the exposed group could be attributed to cessation of breast feeding and its complication and increased NSE in the studied markers.  相似文献   
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74.
The problem of finite-time stability for linear discrete-time systems with time-varying delay is studied in this paper. In order to deal with the time delay, the original system is firstly transformed into two interconnected subsystems. By constructing a delay-dependent Lyapunov–Krasovskii functional and using a two-term approximation of the time-varying delay, sufficient conditions of finite-time stability are derived and expressed in terms of linear matrix inequalities (LMIs). The derived stability conditions can be applied into analyzing the finite-time stability and deriving the maximally tolerable delay. Compared with the existing results on finite-time stability, the derived stability conditions are less conservative. In addition, for the stabilization problem, we design the state-feedback controller. Finally, numerical examples are used to illustrate the effectiveness of the proposed method.  相似文献   
75.
Despite the critical role of individuals’ perceived security in an online environment, previous research has not attempted to comprehensively study the influences and interrelations between the determinants of online individuals’ perceived security. This research employs five theories to examine the interrelations that might exist between the antecedents of individuals’ perceived security in online environment in Malaysia. It is the first attempt to empirically examine the interrelations of the confidentiality related factors identified in the literature which is a significant original contribution. A questionnaire was the primary research methodology and structural equation modeling was employed to test the hypotheses. The findings suggest that individuals’ perceptions about security are significantly influenced by their perceived technical protection while technical protection was found to be influenced by website design features. Moreover, it was found that individuals’ perceptions toward internally provided assurances are highly influenced by externally provided assurances. However, the results found no significant relations between internally and externally provided assurances about a website's security. The findings imply that e-retailers should launch well-designed websites and communicate the technical protection capabilities of their websites to address individuals’ security concerns. The results also suggest that e-traders should consider the factors influencing individuals’ security perceptions when designing/developing their websites.  相似文献   
76.
The paper identifies changes that have occurred in the Web environment over the last decade which have gradually rendered server logs, once the preeminent source of intelligence on usage and information‐seeking behaviour, an ineffective, impractical, and uneconomic resource. It also looks at the implications of these changes for information professionals and publishers who have come to rely on this data to understand the behaviour of clients and customers in the virtual environment. Ubiquitous and expanding, Google Analytics generates statistics about a website's traffic and traffic sources, albeit from a marketers' perspective, is evaluated as a possible replacement; something which might plug the user knowledge gap which is worryingly opening up, or maybe even, put us in a better position overall. The paper is built on the knowledge and experience of evaluating server logs for more than a decade, mostly for publishers and libraries, and also on two recent projects where server log analysis was supplemented with Google Analytics.  相似文献   
77.
Collaboration in science is a process in which two or more authors share their ideas, resources and data to create a joint work. This research compares coauthorship networks of Iranian articles in library and information science (LIS), psychology (PSY), management (MNG), and economics (ECO) in the ISI Web of Knowledge database during 2000–2009, and uses network analysis for the visualization of coauthorship networks. Data include all articles with at least one Iranian author and indexed in ISI's Social Science Citation Index (SSCI) for the fields of LIS, PSY, MNG, and ECO. Indicators such as the Collaborative Index (CI), Degree of Collaboration (DC) and Collaboration Coefficient (CC) were calculated for each discipline. Results show that two or three authors were the most common number of authors per paper, and authors of PSY tended to have more multi-authored articles, compared to the other disciplines. LIS had the lowest rank regarding CC. MNG had the densest coauthorship network, and PSY had the sparsest. Iranian authors in the field of PSY mostly collaborated with those in the U.S., while LIS and MNG authors tended to collaborate with U.K. authors, and ECO authors tended to collaborate with Canadians.  相似文献   
78.
Endothelial cell death due to increased reactive oxygen species(ROS) may contribute to the initial endothelial injury,which promotes atherosclerotic lesion formation.Piper sarmentosum(PS),a natural product,has been shown to have an antioxidant property,which is hypothesized to inhibit production of ROS and prevent cell injury.Thus,the present study was designed to determine the effects of PS on the hydrogen peroxide(H2O2)-induced oxidative cell damage in cultured human umbilical vein endothelial cells(HUVECs).In this experiment,HUVECs were obtained by collagenase perfusion of the large vein in the umbilical cord and cultured in medium M200 supplemented with low serum growth supplementation(LSGS).HUVECs were treated with various concentrations of H2O2(0-1000 μmol/L) and it was observed that 180 μmol/L H2O2 reduced cell viability by 50% as denoted by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay.Using the above concentration as the positive control,the H2O2-induced HUVECs were concomitantly treated with various concentrations(100,150,250 and 300 μg/ml) of three different extracts(aqueous,methanol and hexane) of PS.Malondialdehyde(MDA),superoxide dismutase(SOD),catalase(CAT) and glutathione peroxidase(GPX) levels showed a significant increase(P0.05) in HUVECs compared to the negative control.However,PS extracts showed a protective effect on HUVECs from H2O2-induced cell apoptosis with a significant reduction in MDA,SOD,CAT and GPX levels(P0.05).Furthermore,PS had exhibited ferric reducing antioxidant power with its high phenolic content.Hence,it was concluded that PS plays a beneficial role in reducing oxidative stress in H2O2-induced HUVECs.  相似文献   
79.
This research paper is a pilot study that investigated the suitability of adopting an automated balanced scorecard for managing and measuring the performance excellence of academic staffs in the higher education setting. A comprehensive study of related literature with requirements elicited from the target population in a selected premier university in Malaysia through document analysis, interviews and survey questionnaires provided the foundation for the system development. By adopting the balanced scorecard, the proposed system provided a means for top down alignment of organisational objectives while creating a medium of communication between the lecturers and management. Though the method suggested in this study primarily focuses on the academic staff, it addresses the lack of a representative form of performance measurement for lecturers that accommodates the complexities of the profession while providing the potential adoption of an unconventional method to encourage excellence and development amongst all levels of employees in the industry.  相似文献   
80.
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