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61.
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   
62.
The present study has been conducted in 80 cases, out of which 28 were of strangulated and 52 of non-strangulated intestinal obstruction. It has been observed that serum lactate dehydrogenase of more than 300 I. U./litre in first 24 hours to 72 hours is highly suggestive of strangulated intestinal obstruction.  相似文献   
63.
The construct validity of maternal mind-mindedness (MM) was investigated in the context of its relations with children's later understanding of mind. MM measures were obtained from infant-mother (N = 52) interactions at 6 months, and from maternal interviews at 48 months. Children's understanding of mind was assessed using theory of mind (ToM) tasks at 45 and 48 months, and a stream of consciousness (SoC) task at 55 months. One of the early MM measures--mothers' appropriate mind-related comments--was a positive independent predictor of: (a) MM at 48 months, and (b) ToM and SoC performance at 45 to 55 months. Path analyses suggested direct links between mothers' use of appropriate mind-related comments and children's later understanding of mind.  相似文献   
64.
Students in a physical sciences course were introduced to cooperative learning at the University of Queensland, Gatton Campus. Groups of four to five students worked together in tutorial and practical sessions. Mid-term and practical examinations were abolished and 40% of total marks were allocated to the cooperative learning activities. A peer- and self-assessment system was successfully adapted to account for individual performance in cooperative learning group assignments. The results suggest that cooperative learning was very well received by students, and they expressed willingness to join cooperative learning groups in other courses. In addition, cooperative learning offered many benefits to students in terms of graduate attributes such as teamwork, communication, lifelong learning and problem-solving.  相似文献   
65.
66.
Singapore English can be described as diglossic, that is, most of the proficient adult users of English in Singapore use two grammatically distinct varieties of English: (1) Singapore Colloquial English, which is used with close friends, to children, and informally in general and (2) Standard English, which is used in writing, in formal situations, and is associated with education. Singapore Colloquial English is informally learnt, while the teaching of Standard English is a primary responsibility of the school.

Students at the National University of Singapore, and especially those taking courses in the Department of English Language and Literature, can be expected to show the highest attainment levels in Standard English of those coming from the education system. The oral skills of these students are generally very good, both in comprehension and production. Their control of vocabulary is outstanding. While some students still have problems producing Standard English (especially in the area of tenses) most students make few grammatical errors. However, they do have problems with the organisation of material, report writing, and techniques of argumentation. Students also tend to write in a uniformly journalistic style, having little control over the use of different styles for different types of writing. Awareness of the functions of English in Singapore may help teachers to understand the importance of stylistic appropriacy.  相似文献   

67.
We cannot really understand how to create computer support for collaborative learning without first becoming clearer about what we mean by communication, collaboration, and learning. After distinguishing several conceptions of communication, and highlighting transformative communications for learning, I consider how, via broadband telepresence, distributed multimedia learning environments may establish such communications by adequately acknowledging the social and material embeddedness of everyday communication. I then describe high-priority areas for advancing this agenda: in sociocultural theory, in examining conceptual change by means of conversational analysis, and in technically establishing affordances of tools to sustain and potentially enhance joint activity beyond the here-and-now and the face-to-face.  相似文献   
68.
At Curtin University, student perceptions of teaching and learning are gathered and reported online through eVALUate, a system that includes separate unit and teaching surveys. This article reports the development and validation of one of those surveys, the eVALUate teaching survey, which was developed based on the research literature on excellent teaching and evaluation. Since its development in 2006, repeated statistical testing using progressively larger samples has shown that the survey is valid and reliable. Moreover, the way in which the teaching survey is deployed within eVALUate, appended to the unit survey, which provides crucial institutional data, has significantly increased university response rates. This validated instrument is used for self-reflection, professional development, and rewarding staff.  相似文献   
69.
Cloud computing has become the buzzword in the industry today. Though, it is not an entirely new concept but in today's digital age, it has become ubiquitous due to the proliferation of Internet, broadband, mobile devices, better bandwidth and mobility requirements for end-users (be it consumers, SMEs or enterprises). In this paper, the focus is on the perceived inclination of micro and small businesses (SMEs or SMBs) toward cloud computing and the benefits reaped by them. This paper presents five factors influencing the cloud usage by this business community, whose needs and business requirements are very different from large enterprises. Firstly, ease of use and convenience is the biggest favorable factor followed by security and privacy and then comes the cost reduction. The fourth factor reliability is ignored as SMEs do not consider cloud as reliable. Lastly but not the least, SMEs do not want to use cloud for sharing and collaboration and prefer their old conventional methods for sharing and collaborating with their stakeholders.  相似文献   
70.
Non-alcoholic fatty liver disease shares many features of metabolic syndrome and its presence could signify a substantial cardiovascular risk above and beyond that conferred by individual risk factors. This study is an attempt to investigate the association of non-alcoholic fatty liver disease with carotid intima-media thickness and plaque as surrogate measures of increased cardiovascular risk. The study was conducted on 645 non diabetic, non alcoholic subjects in the age range of 20–60 years. Metabolic syndrome was assessed by using ATP III and ADA (2005) criteria. Anthropometric factors—waist circumference and blood pressure were measured. Fasting serum samples were analyzed for glucose, triglyceride, cholesterol and its fractions, insulin, alanine and aspartate transaminases, gamma glutamyl transferase and free fatty acids. Insulin resistance and secretion were calculated by homeostasis model and insulin sensitivity by QUICKI index. Liver ultrasonographic scanning was used for assessing fatty liver. Carotid atherosclerosis was assessed by B-mode ultrasonography of common carotid artery and internal carotid artery. The prevalence of non-alcoholic fatty liver disease was 15.6 % in non alcoholic population and 68.5 % of non-alcoholic fatty liver disease had metabolic syndrome, which was associated with hyperinsulinemia, insulin resistance, insulin insensitivity along with elevated levels of waist circumference, blood pressure, triglyceride, FFA and decreased HDL cholesterol. NAFLD patients had markedly greater carotid intima media thickness than non NAFLD subjects with MCIMT of 591.6 ± 108 and 489.5 ± 132.4 μm (P < 0.001) and plaque prevalence of 19.2 and 2.2 %, respectively, thus the carotid intima media thickness is associated with NAFLD.  相似文献   
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