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21.
Protein fraction termed P2 was obtained from sonicates of Mycobacterium smegmatis, subjected to ammonium sulphate precipitation. P2 fraction was further fractionated into 4 fractions (PeakI-IV) by DEAE cellulose ion-exchange chromatography. ELISA was performed on the sera of 104 tuberculous cases and 62 controls, using P2 fractions Peak I as test antigens. Though the mean ELISA values in tuberculous cases were higher than the controls, no statistically significant difference was found between the two. Antigens P2, Peak I and IV were tested on Western blots with pooled sera from tuberculous cases as well as controls. P2 fraction, Peak-I and IV were separated on PAGE-SDS, electroblotted onto nitrocellulose Sheets and the blots were subjected to ELISA. Peak IV appeared as a single band (M.W. 55,000). P2 fraction exhibited some discriminatory bands on development of blots.  相似文献   
22.
Sixteen weeks of chronic vitamin C deficiency, induced in guinea pigs by restricted vitamin C intake, resulted in a marked increase in the serum total LDL- and VLDL- cholesterol, triglycerides and total lipids. HDL-cholesterol decreased resulting in a highly significant increase in LDL/HDL ratio. The results reconfirm that vitamin C deficiency causes changes in blood lipid profile which could promote atherogenesis.  相似文献   
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This paper focuses on the perspectives of Years 7 and 8 Pasifika students on mathematics learning, in particular their views about the communication of solution strategies with others (their peers), and their teacher. Pasifika students' ideas about the importance of communicating their mathematical reasoning and strategies to peers and teachers were analysed and themes identified. While most students were in agreement about the importance of explaining their thinking to others, there was considerable variation in the reasons they gave for their views. The findings are interpreted in relation to socio-cultural theory and recent writing about requirements for citizenship in the twenty-first century.  相似文献   
25.
In the present study which was aimed to see the effect of zinc on pentylenetetrazole induced convulsive threshold in rats we found that zinc sulfate 100 μg intracerebroventricularly) and pentylenetetrazole (50 mg/kg intraperitoneally) produced dose related seizure activity; however, pretreatment with zinc decreased the threshold, increased the severity, incidence of multiple seizures and total duration of pentylenetetrazole induced seizures. Diazepam (5 mg/kg intraperitoneally) pretreatment increased the threshold and lowered the incidence of convulsions in zinc induced seizures which further confirms that the convulsive effect of zinc is through inhibition of gamma aimino butyric acid.  相似文献   
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Everybody is familiar with the ubiquitous term ‘species’. But what is a species? Undeniably, this is one of the most complex dilemmas in the history of biology. There is no other concept in biology as elementary yet controversial as the concept of species. In practice, a species is regarded as the fundamental unit of comparison in all biological disciplines like systematics, evolution, ecology, ethology, physiology, and genetics. However, little agreement exists in the scientific community regarding the nature of species, whether it is a real entity or a cultural artifact, its biological significance or how to delineate a species. This article is a review of the seemingly endless debate on the species concept and its implications.  相似文献   
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Premature coronary artery disease (CAD) is common in India. We, therefore, studied oxidative stress, dyslipidemia, and high sensitivity-C reactive protein (hs-CRP) levels in young CAD patients. Present study consisted of male CAD patients below 40 years and age and sex matched healthy controls (n=30 each). Fasting blood samples were analyzed for serum lipid profile, malondialdehyde, antioxidant enzymes and hs-CRP levels. Dyslipidemia was observed in 90% of the young CAD patients, of which 72.2% showed increased serum triglycerides and decreased HDL-cholesterol. LDL-cholesterol levels were high in 77.8%. Serum malondialdehyde and hs-CRP levels were increased significantly (p<0.0001) as compared to controls. hs-CRP levels were in high risk range in all the young patients. However, glutathione peroxidase activity was reduced significantly (p<0.05). Our data suggests that elevated hs-CRP levels along with dyslipidemia and oxidative stress adds to the predictive value of premature CAD in young Indians.  相似文献   
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This article reports on the third phase of a larger study that explored the perceptions of teachers about distributed leadership practices for inclusive education (IE) in primary schools involved in IE reform in Bangladesh. The Distributed Leadership Practice for Inclusive Education scale was developed specifically for this study to collect data. Participants for the present study were head teachers and teachers from 308 public primary schools. The results of this study indicate that teachers perceived that distributed leadership practices for IE were present in primary schools in Bangladesh. The findings indicate that teachers' perceptions about distributed leadership practices for IE have a significant positive correlation with their satisfaction about the implementation of IE policy.  相似文献   
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The purpose of this paper was to investigate Malaysian primary pre-service teachers’ perceptions of students’ disruptive behaviour and their self-reported strategies to prevent and to manage such behaviours. Results indicate that Malaysian pre-service teachers understand disruptive behaviours to be those that disrupt the learning and teaching process. They identified the cause of student disruptive behaviour as factors residing within the individual student. Pre-service teachers here reported preventative strategies in terms of changing teaching strategies and threats to use punishment. When addressing students’ disruptive behaviour, pre-service teachers reported that they would use one-to-one counselling with students and remove tokens or hold back rewards. A discussion regarding the implications for teacher education institutions and future research concludes this paper.  相似文献   
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