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1.
In previous studies, we have reported first in vivo evidence of copper deposition in the choroid plexus, cognitive impairments, astrocytes swelling (Alzheimer type II cells) and astrogliosis (increase in number of astrocytes), and degenerated neurons coupled with significant increase in the hippocampus copper and zinc content in copper-intoxicated Wistar rats. Nonetheless, hippocampus iron levels were not affected by chronic copper-intoxication. Notwithstanding information on distribution of copper, zinc and iron status in different regions of brain due to chronic copper exposure remains fragmentary. In continuation with our previous study, the aim of this study was to investigate the effects of intraperitoneally injected copper lactate (0.15 mg Cu/100 g body weight) daily for 90 days on copper, zinc and iron levels in different regions of the brain using atomic absorption spectrophotometry. Copper-intoxicated group showed significantly increased cortex, cerebellum and striatum copper content (76, 46.8 and 80.7 % increase, respectively) compared to control group. However, non-significant changes were observed for the zinc and iron content in cortex, cerebellum and striatum due to chronic copper exposure. In conclusion, the current study demonstrates that chronic copper toxicity causes differential copper buildup in cortex, cerebellum and striatum region of central nervous system of male Wistar rats; signifying the critical requirement to discretely evaluate the effect of copper neurotoxicity in different brain regions, and ensuing neuropathological and cognitive dysfunctions.  相似文献   
2.
This paper examines perceptions of professional and organizational identity of teacher educators in a ‘new’ University of Technology in South Africa, resulting from several recent mergers of colleges of education and colleges of technology mainly serving formerly disadvantaged students and schools. The findings show that most staff consider teaching and research as dichotomous. Research activities are seen to satisfy the institutional requirements for securing research funding and producing publications. Professional identities could be strengthened by a faculty-wide debate on the specific profile of teacher education in a University of Technology, resulting also in an agreed research ethos. Peer support in collaborative research groups with a focus on own practice is seen as an opportunity to strengthen research expertise.  相似文献   
3.
Montgomery multiplication over rings   总被引:1,自引:0,他引:1  
Montgomery multiplication of two elements a and b of a finite field Fq is defined as abr-1 where r is a fixed field element in . In this paper we define Montgomery multiplication of elements a(x) and b(x) in a polynomial ring modulo the ideal generated by a reducible polynomial f(x). We then show that Montgomery multiplication over a field represented by a polynomial ring modulo an irreducible pentanomial can be performed more efficiently in terms of time delay by embedding the field in a quotient of a polynomial ring modulo a reducible trinomial. The trinomial has a degree that is slightly higher than that of the pentanomial, thereby increasing the number of gates in the multiplier by a small amount.  相似文献   
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Psoriasis is a common and an inflammatory skin disease. Trace elements play an important role in the skin metabolism such as keratinisation and melanin formation as well as immunological and inflammatory reactions. Henceforth, the present study was aimed to evaluate the essential metals with special reference to Cu and Zn. In this study, 72 psoriatic patients and 50 controls were enrolled. On the basis of PASI score psoriatic group comprising of 48 mild and 24 severe psoriatic patients were grouped. The serum trace elements analysis in the subjects revealed that serum Cu levels and Cu/Zn ratio was significantly higher in the psoriatic patients as compared to controls. Interestingly, severity of the psoriasis was well correlated with the serum Cu levels. Taking together, all these findings suggest that Cu may be a major culprit in the pathogenesis as well as in the severity of the disease.  相似文献   
7.
Evidence of the value of constructivist theory in the classroom is especially important for educational practice in areas of poverty and social challenge. Research was undertaken in 2010 into the application of constructivist theory on instructional design. The findings of this research are particularly relevant to the current curricular crisis in South Africa which threatens to side-line constructivist priorities and return learners to rote learning from textbooks. The findings are situated here within the national debate over curricular design and instructional models. Placing instructional design within the larger context of national pedagogical contestation provides important evidence of the central role of Freirean imperatives for South Africa’s educational future. This article indicates that a constructivist framework, when pertinently arranged, provides holistic and sustainable procedures for knowledge creation. The findings from the research project showed that, in an environment conducive to learning, learners become self-motivated and better able to master the next phase of the curriculum. As a result of the constructivist framing, participants grew into strategic and effective learners who took responsibility for their own learning. These findings add weight to the call for reconsideration of constructivist foundations in national curriculum design.  相似文献   
8.
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   
9.
Drawing on evidence from a wider study on the cost and cost-effectiveness of sexuality education programmes in six countries, and focusing on the examples of India and Nigeria, this paper argues that advocacy is a key, yet often neglected component of school-based sexuality education programmes, especially where sex and sexuality are politically or culturally sensitive issues. It also suggests that advocacy is not a one-off activity but needs to be carried out continuously and adapted as contexts and needs change. Overall, this piece recommends that advocacy should be a key component of sexuality education work, and needs to be planned and budgeted for. Without such investment, country-level sexuality education programmes are likely to fail.  相似文献   
10.
Renal cell carcinoma is the most common form of the kidney cancer accounting for more than 85% of the cases of which clear cell renal cell carcinoma (ccRCC) is the major histological subtype. The central molecular signature for ccRCC pathogenesis is the biallelic inactivation of VHL gene due to the presence of mutations/hyper-methylation/complete gene loss, which results in the downstream HIF activation. These events lead to increased tyrosine kinase receptor signalling pathways (RAS/MEK/ERK pathway, PI3K/AKT/mTOR pathway and NF-κB pathway), which through their downstream effector proteins causes the cell to proliferate and migrate. Recent studies have shown that VHL inactivation alone is not sufficient to induce the tumor. Mutations in numerous other genes that codes for chromatin modifiers (PBRM1, SETD2 and BAP1) and signalling proteins (PTEN and mTOR) have been identified along with activation of alternate signalling pathways like STAT and Sonic Hedgehog (SHH) pathway. It has also been shown that STAT pathway also works cooperatively with HIF to enhance the tumor progression. However, SHH pathway reactivation resulted in tumor regardless of the VHL status, indicating the complex nature of the tumor at the molecular level. Therefore, understanding the complete aetiology of ccRCC is important for future therapeutics.  相似文献   
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