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91.
Nancy L. Williams Karen H. Larwin 《Journal of Research on Technology in Education》2016,48(3):143-158
This study explores the impact of one-to-one computing on student achievement in Ohio high schools as measured by performance on the Ohio Graduation Test (OGT). The sample included 24 treatment schools that were individually paired with a similar control school. An interrupted time series methodology was deployed to examine OGT data over a period of 5 to 8 years. Overall student performance and content-specific achievement in math, reading, science, social studies, and writing were not significantly affected by the introduction of 1:1 computing. Treatment schools using a netbook device produced the greatest overall change in scores. 相似文献
92.
J. I. Anetor F I Ajose T. S Akingbola 《Indian journal of clinical biochemistry : IJCB》2005,20(1):193-197
A 64-year-old security guard and longstanding known hypertensive presented with hypertensive heart disease (HHD), weight loss,
an enlarged prostate, and a spontaneously fractured rib. Malignancy of the prostate with possible metastases to the ribs was
strongly suspected. Biochemical profiling revealed a paraprotein. Other biochemical and hematological correlates that were
on hand before serum protein electrophoresis were rather atypical. Paraprotein studies by immunofixation revealed IgA myelomatosis.
Unlike previous reports from Caucasians there was normocalcaemia, normal protein level, microcytic hypochromia, low MCHC,
cholesterol level at the lower limit of the reference range and normal urea level (in the face of markedly raised creatinine
level). Nutritional modulation of the classical laboratory features of this disease may account for the fairly atypical laboratory
picture.
The need to appreciate the influence of nutritional status on the laboratory (especially biochemical) features of a disease
and thus interpretation of diagnostic tests appears of exceptional current importance, given the widening gap in socioeconomic
status and the level of poverty between the resource poor and developed countries from which the classical, clinical and laboratory
features of most diseases were first described.
This case report reminds of the need not only to recognize theoretically the impact of nutritional status on the laboratory
characteristics of a disease but of the practical application of the nutritional perspective in the interpretation of diagnostic
investigations, especially in nutritionally disadvantaged communities. 相似文献
93.
Robert J.P. Williams 《Endeavour》1984,8(2):65-70
Zinc is as common as iron in biology. It is usually thought to be a trace element required only for catalysis. Here it is shown that the role of zinc is much more fundamental not only in catalysis but in inhibitory control. There may well be several such control elements—calcium, iron, manganese, magnesium, and zinc. 相似文献
94.
G. M. Sankolli M. I. Khatkhatay M. P. Desai D. K. Pardhe P. C. Ishrad U. M. Joshi 《Indian journal of clinical biochemistry : IJCB》1992,7(1):71-74
Aprototype kit for the detection of occurrence of ovulation based on urinary pregnanediol glucuronide estimations by ELISA
was developed in our laboratory. This kit was sent for evaluation at 4 centres in Bombay and Pune, India. The diagnosis of
ovulation/anovulation based on the results of the kit is comparable with that based on reference parameters commonly used
(ultrasonography of ovarian follicles and serum progesterone estimations). The accuracy of the test was 93.5%, specificity
was 87.5% and sensitivity was 95.7%. This rapid indigenous test can be very useful in assessing ovulatory status of the woman
by the clinicians in their offices. 相似文献
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Externalities as conventionally defined miss many of the spillovers that are both causes and consequences of the technological changes that underlie economic growth. We introduce a much wider concept called technological complementarities. New general purpose technologies (GPTs) rejuvenate the growth process by creating technological complementarities, which are adequately measured neither by total factor productivity (TFP) nor by externalities. There would be major gains from technological change even if the returns on capital invested in innovation never exceeded the returns on investing in existing technologies so that there were neither externalities nor positive changes in TFP. 相似文献
100.
Three aspects of the most important problem questionused in agenda-setting research to measure issue salience amongthe public were examined. A split-ballot design in a state-widesurvey compared versions of the public agenda with a socialframe of reference versus a personal frame of reference, versionsusing the traditional term problem versus issue,and the effects of question order. High correlations betweenthe different versions were found in all three sets of comparisons. 相似文献