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921.
S. Narayanan 《Indian journal of clinical biochemistry : IJCB》1996,11(1):12-16
A number of pre analytical variables affect lipid determinations. These include posture during blood sampling, the duration of tourniquet application and fasting, the time of day when blood is collected, the concentration and type of anticoagulant used for blood collection to name just a few. Effect of life style such as diet, alcohol and caffeine consumption, smoking, and exercise influence lipid determinations. Disease states such as infection, diabetes, nephrotic syndrome and heart disease culminating in myocardial infarction and conditions such as obesity and pregnancy influence lipid profiles. A variety of drugs ranging from diuretics to oral contraceptives to immunosuppressive drugs induce alterations in the patient's lipid profile. Post analytical variables impacting on the interpretation of laboratory data such as in the determination of the true mean of a lipid constituent would depend on the number of specimens analyzed, the analytical variability of the method and approaches to handling data such as the use of relative range to estimate the effect of biological variability on the computed mean value. 相似文献
922.
R. Kumar S. B. Pachori G. K. Senger Satyanand L. D. Joshi 《Indian journal of clinical biochemistry : IJCB》1994,9(2):72-74
Aim of present study was to compare the adenosine deaminase (ADA) activity in various types of arthritis conditions with synovial
effusion. No. significant difference was observed in ADA activity in serum of control and study groups but results have shown
a definite pattern of ADA activity in synovial fluid in various arthritic conditions. The highest value of ADA activity was
observed in synovial fluid of patients with tubercular arthritis followed by rheumatoid, septic, osteo and post traumatic
arthritis. Thus measurement of ADA activity in synovial fluid can be used as a parameter of differential diagnosis of arthritis
specially tubercular in initial stages. 相似文献
923.
The structure of a retrospective information retrieval system that uses equifrequent word or text fragments is described, and its advantages over word oriented systems are mentioned briefly. Word fragments are proposed as retrieval elements, and a discussion is given of the changes required in order to process a query. Some necessary modifications in the treatment of logical operators are described, and two conditions are postulated as necessary for the successful operation of the system. Aspects of query processing are illustrated by experimental results obtained from single and two-term queries applied to a portion of the MARC tapes. 相似文献
924.
Nomographs for determining the filter order of classical filters based on selectivity requirements are presented. The selectivities for a variety of standard classical filters are summarized in equation form and the general selectivity nomograph is constructed. The selectivity equations are then converted into nomograph form by applying the relationship between the transfer function and the response slope. Design examples are presented to demonstrate the usefulness of the selectivity nomographs. These nomographs can be used to gauge filter performance and combined with optimization techniques can yield superior classical filter designs. 相似文献
925.
A study is made of the orthogonal polynomials on certain curves in the complex plane. Necessary and sufficient conditions for a set of polynomials to be orthogonal on the curves are obtained in terms of symmetric matrices. The relations of the symmetric matrices to Toeplitz matrices and innerwise matrices are shown. 相似文献
926.
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
927.
928.
Profiles of emergent literacy skills among preschool children who are at risk for academic difficulties 总被引:1,自引:0,他引:1
Sonia Q. Cabell Laura M. JusticeTimothy R. Konold Anita S. McGinty 《Early childhood research quarterly》2011,26(1):1
The purpose of this study was to explore patterns of within-group variability in the emergent literacy skills of preschoolers who are at risk for academic difficulties. We used the person-centered approach of cluster analysis to identify profiles of emergent literacy skills, taking into account both oral language and code-related skills. Participants were 492 preschoolers (aged 42-60 months) enrolled in needs-based programs. In the fall of the academic year, children were administered eight measures of emergent literacy: four oral language measures (i.e., expressive and receptive grammar, expressive and receptive vocabulary) and four code-related measures (i.e., print concepts, alphabet knowledge, name writing, and rhyme). Controlling for age, hierarchical-agglomerative and K-means cluster analysis procedures were employed. Five psychometrically sound profiles emerged: highest emergent literacy (prevalence = 14%); three profiles with average oral language and differential code-related abilities (16%, 24%; 23%); and lowest oral language with broad code-related weaknesses (23%). Profiles were then compared on midyear teacher ratings of emergent literacy as well as end-of-kindergarten literacy performance; results provided convergent evidence of predictive validity. This study highlights the considerable heterogeneity of emergent literacy abilities within an “at-risk” group. The resulting profiles have theoretical and practical relevance when examining both concurrent relationships between oral language and code-related skills as well as longitudinal relationships between early patterns of performance and later reading achievement. 相似文献
929.
The purpose of this study was to concurrently examine the development of written language across different writing tasks and
to investigate how writing features develop in preschool children. Emergent written language knowledge of 372 preschoolers
was assessed using numerous writing tasks. The findings from this study indicate that children demonstrate knowledge about
writing before beginning school and receiving formal instruction. There was clear evidence to support the claim that universal
writing features develop before language-specific features. Children as young as 3 years possess knowledge regarding universal
and language-specific writing features. Preschoolers appear to progress along a continuum from scribbling to conventional
spelling. Although this progression is sequential, children’s writing proficiency is task dependent. Implications of these
findings on writing development are discussed. 相似文献
930.