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91.
Children with specific disorders of language have failed to develop normal means of spoken and written communication. International studies suggest that 5–10% of children enter school with a significant language disorder that puts them at risk educationally and also affects their social and emotional development.

The invisible nature of language disorders makes early detection and remediation difficult. In multilingual settings, such as Singapore, early detection may be particularly difficult, and remediation is complicated by the desirability of maintaining the range of languages used in the home and at school. Two case studies of specific spoken language disorder and two of written language disorder are presented to illustrate means of remediation and the importance of early intervention.  相似文献   

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Oxygen derived free radicals have been implicated in a number of clinical disorders including atherosclerosis (1), ischemic heart disease (IHD) (2), post ischemic reperfusion injury (3) and respiratory distress syndrome (4). These radical are generated by sequential reduction of molecular oxygen; the primary product being superoxide anion (O2 .−) which is subsequently reduced to hydrogen peroxide (H2O2), hydroxy1 radical (OH.) and singlet oxygen (1O2). However the evidence for ODFR induced cell damage in various clinical disorders is still debated and rests largely on free radical scavenging studies, through electron paramagnetic resonance spectroscopic (EPRS) studies have provided direct evidence for ODFR generation following coronary artery ligation (5). By definition, a free radical is an atom, ion or molecule with one or more unpaired electrons (the presence of unpaired electron in a free radical being represented by a superscribed bold dot-R.) and may be formed as a result of homolytic fission of a covalent bond or by electron transfer reactions, and may have cationic (NH3 +), anionic (O2 .−) or neutral (NO) characteristics. The most important in vivo source for these radical species have been found to be univalent biochemical redox reactions involving oxygen. (a) A:B→A.+B. (b) A:+B→A.+B.  相似文献   
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Electrical power supply has grown enormously during this century. In 1950 the total capacity of generators producing electricity in India was less than 3000 MW. Today, the power generating capacity is around 120,000 MW. The polyphase AC system, which is to a large extent the legacy of Nikola Tesla, is central to all power generation. Power systems these days are complex interconnected networks spread across the country. How are they structured? How have we been doing in India?  相似文献   
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A 50 year old male was admitted in our hospital with anemia and impaired renal function. He was subsequently found to have extremely elevated serum phosphate level (24 mg/dL, reference interval: 2.5–4.5 mg/dL) with normal serum calcium when assayed on a Beckman Coulter AU 480® analyser. Clinico-biochemical discrepancy led to the suspicion of spurious hyperphosphatemia. Serum total protein was grossly elevated with gross reversal of albumin to globulin ratio. Serum electrophoresis revealed a large M band and was confirmed as Ig G-Kappa type on immunofixation. Subsequently a bone marrow aspiration biopsy confirmed the diagnosis of multiple myeloma. The patient serum was then reassayed for phosphate on a Vitros® 250 Dry Chemistry platform and the result was within normal reference interval. Paraproteinemias are a common cause of analytical interference in clinical biochemistry laboratories and as multilayered film technology platforms like Vitros® assay most routine analytes on a protein free filtrate they are unaffected by paraprotein interference. Clinically discordant patient results should always be interpreted keeping such interferences in mind.  相似文献   
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Investigation of single molecule DNA dynamics in confined environments has led to important applications in DNA analysis, separation, and sequencing. Here, we studied the electrophoretic transport of DNA molecules through nanochannels shorter than the DNA contour length and calculated the associated translocation time curves. We found that the longer T4 DNA molecules required a longer time to traverse a fixed length nanochannel than shorter λ DNA molecules and that the translocation time decreased with increasing electric field which agreed with theoretical predictions. We applied this knowledge to design an asymmetric electric pulse and demonstrate the different responses of λ and T4 DNA to the pulses. We used Brownian dynamics simulations to corroborate our experimental results on DNA translocation behaviour. This work contributes to the fundamental understanding of polymer transport through nanochannels and may help in designing better separation techniques in the future.  相似文献   
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During the last few decades research activities have grown rapidly in Ethiopia. Introduction of higher education and foreign assistance for this purpose have led the Ethiopian Government to set up several research institutes in the country. The Institute of Ethiopian Studies is one of them, set up to enable research activities in various areas of Ethiopian culture as well as to provide a documentation centre for them. Information and documentation are considered to be the infrastructure of research work. The present state of information and documentation services of the Institute is briefly described along with its history, activities and sections. The importance of introducing some new devices, such as compiling bibliographies, cumulative indexes, book lists and starting a newsletter to keep the researchers abreast of new developments at the Institute.  相似文献   
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