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This study is designed to isolate and purify a novel anti-clotting protein component from the venom of Enhydrina schistosa, and explore its biochemical and biological activities. The active protein was purified from the venom of E. schistosa by ion-exchange chromatography using DEAE-cellulose. The venom protein was tested by various parameters such as, proteolytic, haemolytic, phospholipase and anti-coagulant activities. 80 % purity was obtained in the final stage of purification and the purity level of venom was revealed as a single protein band of about 44 kDa in SDS-polyacrylamide electrophoresis under reducing conditions. The results showed that the Potent hemolytic activity was observed against cow, goat, chicken and human (A, B and O positive) erythrocytes. Furthermore, the clotting assays showed that the venom of E. schistosa significantly prolonged in activated partial thromboplastin time, thrombin time, and prothrombin time. Venomous enzymes which hydrolyzed casein and gelatin substrate were found in this venom protein. Gelatinolytic activity was optimal at pH 5–9 and 1H NMR analysis of purified venom was the base line information for the structural determination. These results suggested that the E. schistosa venom holds good promise for the development of novel lead compounds for pharmacological applications in near future.  相似文献   
844.
Knowledge creation is one of the most important dynamic capabilities that firms can use to develop new assets, which can represent the basis for future innovations. Within a context of growing globalisation, the acquisition and creation of knowledge is one of the main objectives sought with international expansion. The consideration of intellectual capital within the knowledge creation process in subsidiaries offers an innovative way to undertake knowledge management practices in multinationals. Theoretical and empirical works can be found in the literature about intellectual capital. However, very few studies link intellectual capital to knowledge creation in multinationals. Seeking to fill this gap, the purpose of this paper is to develop and test a model that includes the main intangibles belonging to structural and relational capital that can influence knowledge creation in Spanish subsidiaries of foreign multinational firms belonging to high-technology and knowledge-intensive sectors. Theoretical, empirical and managerial contributions result from this paper.  相似文献   
845.
Are preservice teachers prepared to teach struggling readers?   总被引:1,自引:0,他引:1  
Reading disabilities such as dyslexia, a specific learning disability that affects an individual’s ability to process written language, are estimated to affect 15–20% of the general population. Consequently, elementary school teachers encounter students who struggle with inaccurate or slow reading, poor spelling, poor writing, and other language processing difficulties. However, recent evidence may suggest that teacher preparation programs are not providing preservice teachers with information about basic language constructs and other components related to scientifically based reading instruction. As a consequence preservice teachers have not exhibited explicit knowledge of such concepts in previous studies. Few studies have sought to assess preservice teachers’ knowledge about dyslexia in conjunction with knowledge of basic language concepts. The purpose of the present study was to examine elementary school preservice teachers’ knowledge of basic language constructs and their perceptions and knowledge about dyslexia. Findings from the present study suggest that preservice teachers, on average, are able to display implicit skills related to certain basic language constructs (i.e., syllable counting), but fail to demonstrate explicit knowledge of others (i.e., phonics principles). Also, preservice teachers seem to hold the common misconception that dyslexia is a visual perception deficit rather than a problem with phonological processing. Implications for future research as well as teacher preparation are discussed.  相似文献   
846.
This article examines a common problem in higher education – how to create more widespread use of improved practices, often commonly referred to as innovations. I argue that policy models of scale-up are often advocated in higher education but that they have a dubious history in community development and K-12 education and that higher education leaders should shirk policymakers’ push to use a scale-up model of change. These thoughts are conceptual and are based upon a critical review of literature in community development and K-12, but I also draw upon empirical data in reviewing examples of widespread use of innovations in higher education.  相似文献   
847.
The purpose of this study was to examine which emergent literacy skills contribute to preschool children's emergent writing (name-writing, letter-writing, and spelling) skills. Emergent reading and writing tasks were administered to 296 preschool children aged 4-5 years. Print knowledge and letter-writing skills made positive contributions to name writing; whereas alphabet knowledge, print knowledge, and name writing made positive contributions to letter writing. Both name-writing and letter-writing skills made significant contributions to the prediction of spelling after controlling for age, parental education, print knowledge, phonological awareness, and letter-name and letter-sound knowledge; however, only letter-writing abilities made a significant unique contribution to the prediction of spelling when both letter-writing and name-writing skills were considered together. Name writing reflects knowledge of some letters rather than a broader knowledge of letters that may be needed to support early spelling. Children's letter-writing skills may be a better indicator of children's emergent literacy and developing spelling skills than are their name-writing skills at the end of the preschool year. Spelling is a developmentally complex skill beginning in preschool and includes letter writing and blending skills, print knowledge, and letter-name and letter-sound knowledge.  相似文献   
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