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1.
There has been a long‐standing debate about how ‘English’ can be defined. Educational policy changes have typically been driven by differing representations of the subject, and have ranged from broad ‘aesthetic’ definitions to more narrow ‘functional’ views. The present study aims to analyse areas of consensus and contention in stakeholders' discourse regarding English. A questionnaire‐based survey and focus groups were used to explore how teachers and employers viewed English as a subject. Their views were conceptualised into three themes: the importance of functional English; English as atomistic versus holistic study; and English as critical thought. These themes are discussed in relation to historical definitions of ‘English’, and their implications for the future reform of English qualifications.  相似文献   
2.
Evaluation of serum SOD and MDA level was done in 21 first episode renal stone formers, 9 recurrent stone formers, 20 patients with obstructive uropathy other than urolithiasis and 12 patients with urinary infection. Twenty-two healthy volunteers were taken as controls. The level of SOD in respective groups was 2.12±0.84, 2.78±0.85, 1.42±0.31, 1.98±0.70 and 2.32±0.62 units/ml and of MDA was 2.61±1.07, 2.69±1.15, 1.65±0.33, 1.33±0.34 and 1.55±0.48 n mol/ml respectively. The results indicate increased peroxidative stressin nephrolithiasis only. Since SOD level was normal in all groups, this increased peroxidative stress in nephrolithiasis should be due to factors other than this one.  相似文献   
3.
Objective: To study the effect of halo substitution on disubstituted aryl semicarbazones on the anticonvulsant potential and model the activity based on quantum mechanics. Methods: A series of twenty-six compounds of N^4-(4-bromo-3-methylphenyl) semicarbazones were synthesized and evaluated for the anticonvulsant activity in the maximal electroshock seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure threshold tests. Some potential compounds were also tested in the subcutaneous strychnine (scSTY) and subcutaneous picrotoxin (scPIC) seizure threshold tests. The synthesized compounds were tested for behavioral impairment and CNS (central nervous system) depression in mice. Quantum mechanical modelling was carried out on these compounds to gain understanding on the structural features essential for activity. Results: Some compounds possessed broad spectrum anticonvulsant activity as indicated by their effect in pentylenetetrazole, strychnine, picrotoxin and maximal electroshock seizures models in resemblance to other aryl semicarbazone derivatives reported earlier. The higher the difference in HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy levels was, the greater was the activity profile. Conclusion: The pharmacophoric requirements for compounds to exhibit anticonvulsant activity that includes one aryl unit in proximity to a hydrogen donor-acceptor domain and an electron donor have been justified with the molecular orbital surface analysis of the synthesized compounds.  相似文献   
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5.
This study deals with the effects of freeze dried rhizome powder of Curcuma longa (C. longa) dissolved in milk on normal as well as diabetic models. Diabetes of type II and type I was within 3 days of a single administration of doses of 45 and 65 mg kg−1 of streptozotocin respectively. Various parameters such as blood glucose levels, triglycerides, total cholesterol, high density lipoprotein, very low density lipoprotein, low density lipoprotein, serum glutamic oxaloacetic transaminase, serum glutamic pyruvate transaminase, alkaline phosphatase, creatinine, hemoglobin, urine protein and urine sugar in addition to body weight were taken in to consideration and were analyzed after administration of variable doses of rhizome powder. The dose of 200 mg kg−1 was identified as the most effective dose as it increased HDL, Hb and bw (P<0.05) with significant decrease in the levels of blood glucose, lipid profile and hepatoprotective enzymes (P<0.001).  相似文献   
6.
An overview of cricket ball swing   总被引:1,自引:0,他引:1  
The aerodynamic properties of a cricket ball have intrigued cricket players and spectators for years, arguably since the advent of the game itself. The main interest is in the fact that the ball can follow a curved flight path that may not always be under the control of the bowler. The basic aerodynamic principles responsible for the nonlinear flight or ‘swing’ of a cricket ball were identified decades ago and many papers have been published on the subject. Over the last 25 years or so, several empirical investigations have also been conducted on cricket ball swing, which revealed the amount of attainable swing and identified the parameters that affect it. Those findings are reviewed here with emphasis on phenomena such as late swing and the effects of humidity on swing. The relatively new concept of ‘reverse swing’, how it can be achieved in practice, and the role in it of ‘ball tampering’, are also discussed in detail. In particular, the ability of some bowlers to effectively swing an old ball in the conventional, reverse and the newly termed ‘contrast’ swing mode is addressed. A discussion of the ‘white” cricket ball used in the 1999 and 2003 World Cup tournaments, which supposedly possesses different swing properties compared to a conventional red ball, is also included. This is a current overview of cricket ball swing rather than a detailed review of all research work performed on the topic. The emphasis is on presenting scientific explanations for the various aerodynamic phenomena that affect cricket ball swing on a cricket ground.  相似文献   
7.
From January 1992-January 1998, 1404 patients attended the “Breast Clinic” of R.N.T. Medical College M.B. Hospital, Udaipur. Out of these, 11% and 81% patients had breast cancer (B.C.) and benign breast cancer (B.B.D.) respectively. The oxidative load in B.C. was 2.32 times higher than controls, but comparable to B.B.D. β-Carotene deficiency was uncommon in patients, whereas vitamin A deficiency was almost equally common in both B.C. and controls. Most of the patients had almost depleted levels of α-tocopherol and ascorbic acid but their TBAR levels were in normal range. The data in the present study when compared with B.B.D. and other local normal subjects point out: a) oxidative burden in B.C. is a consequence and not the cause of the disease, (b) oxidative stress could be one of the etiological factors in tumor expression, which need not to be malignant and c) α-tocopherol and ascorbic acid are not importantly responsible for higher oxidative burden in B.C.  相似文献   
8.
Vitamin A status was measured in 50 pre-school children with acute and persistent diarrhoea. It was measured by (a) Fluorometric micromethod and (b) Conjunctival impression cytology (CIC). The results were compared with 25 normal children. Vitamin A status was lower in children with persistent diarrhoea whereas the results were comparable between the children with acute diarrhoea and control subjects.  相似文献   
9.
Resistance to interference was examined in rats that received a complex negative patterning discrimination in which XA and XB were followed by food reinforcement and XAB was not. Retention of the discrimination was evident after separate reinforcement of both A and B (Experiment 3), but not after reinforcement of either AB (Experiments 1 and 3) or XAB (Experiments 2 and 3). These data suggest that complex negative patterning discriminations are acquired configurally and that the relative similarity of the original discrimination and subsequent interference trials dictates the final degree of retention observed.  相似文献   
10.
A rational approach for developing effective filaricides awaits greater knowledge on the biochemical pathways operating in filarial parasites. For example, metabolic pathways or key enzymes that are so pivotal to the parasite that their interruption or inhibition causes spontaneous death, could be exploited to develop effective chemotherapeutic agents. Similarly, developing a safe and nontoxic filaricidal will require precise understanding of whether or not the potential molecular target in the parasite is unique or at least different enough from the host system. Recently, we identified a novel transglutaminase enzyme (EC2.3.2.13; TGase) in filarial parasites that plays an important role during their normal growth and development. Based on these principles, TGase may serve as a new target for the development of effective chemotherapeutic agent and vaccine for controlling and preventing the infections caused by these parasites.  相似文献   
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