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排序方式: 共有508条查询结果,搜索用时 15 毫秒
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Background
People forget much of what they learn, therefore students could benefit from learning strategies that yield long-lasting knowledge. Yet surprisingly, little is known about how longterm retention is most efficiently mastered. We studied the value of teacher made in class tests as learning aids and compared two types of teacher-made tests (multiple choice and short-answer tests) with a no test (control) to determine their value as aids to retention learning.Method
The study was conducted on two separate batches of medical undergraduate students. This study compared two types of tests [multiple choice questions (MCQs) and short answer questions (SAQs)] with a no test (control) group. The investigation involved initial testing at the end of the lecture (post instruction), followed by an unannounced delayed retention test on the same material three weeks later. The unannounced delayed test comprising of MCQs and SAQs on the same material was given three weeks later to all the three groups.Results
In batch I, the MCQ group had a higher mean delayed retention score of 10.97, followed by the SAQ group (8.42) and the control group (6.71). Analysis of variance (ANOVA) test and least significance difference (LSD) post hoc test revealed statistically significant difference between the means of the three groups. Similar results were obtained for batch IIConclusion
Classroom testing has a positive effect on retention learning; both short-answer and multiple-choice tests being more effective than no test in promoting delayed retention learning, however, multiple-choice tests are better. 相似文献84.
85.
Background
The care of special children suffering from cerebral palsy, deaf mutism, mental retardation (MR) and post encephalitic sequelae etc. is done in the armed forces at “ASHA” centre supported by Army Wives Welfare Association (AWWA).Methods
The clinical profile and underlying etiological factors in these children were studied.Result
Out of 30 children studied, majority were males. The commonest disability was cerebral palsy, seen in 13 (43%) cases followed by mental retardation in six (20%) and post encephalitic sequlae in four (13%) cases. Convulsions were noticed in 12 (40%) cases. The delayed speech was a significant handicap observed in 27 (90%) cases.Conclusion
Among the etiological factors, natal causes and infections are leading factors in these children and there is an urgent need to strengthen the existing maternal and child health services in our country.Key Words: Cerebral palsy 相似文献86.
87.
Benjamin M. Ellingson Timothy F. Cloughesy Albert Lai Phioanh L. Nghiemphu Whitney B. Pope 《Magnetic resonance in medicine》2012,67(1):237-245
Diffusion‐weighted imaging estimates of apparent diffusion coefficient (ADC) have shown sensitivity to brain tumor cellularity as well as response to therapy. Functional diffusion maps (fDMs) exploit these principles by examining voxelwise changes in ADC within the same patient over time. Currently, the fDM technique involves linear image registration of ADC maps from subsequent follow‐up times to pretreatment ADC maps; however, misregistration of ADC maps due to geometric distortions as well as mass effect from growing tumor can confound fDM measurements. In this study, we compare the use of a nonlinear registration scheme to the current linear fDM technique in 70 patients with recurrent glioblastoma multiforme treated with bevacizumab. Results suggest that nonlinear registration of pretreatment ADC maps to post‐treatment ADC maps improves the clinical predictability, sensitivity, and specificity of fDMs for both progression‐free and overall survival. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
88.
不同氮量全胃肠外营养支持对脓毒症病人蛋白质代谢的影响 总被引:2,自引:0,他引:2
如何提高脓毒症闰人营养支持的效果是当前的热点和难点之一。本实验前瞻性地对比观察了不同蛋白质供应负荷0.25g/V(kg.d)vs0.35gN/(kg.d),在脓毒症病人全有肠外营养支持中对蛋白质代谢状况的影响。结果发现,与低氮量TPN相比,高氮量TPN支持可改善血浆蛋白水平,增加累积氮平衡,但尿中3-MH排出量也有相应增加。 相似文献
89.
Mitchell PL; Clutterbuck RD; Powles RL; De Lord C; Morilla R; Hiorns LR; Titley J; Catovsky D; Millar JL 《Blood》1996,87(11):4797-4803
Human interleukin-4 (huIL-4) has been shown to inhibit the growth in vitro of cells from patients with acute lymphoblastic leukemia (ALL). With the aim of determining whether this cytokine might be useful in the treatment of patients with ALL, the effects of huIL-4 on human B- cell precursor ALL engrafted in severe combined immunodeficient (SCID) mice were examined. The inhibition of [3H] thymidine uptake of primary ALL cells by huIL-4 was maintained following engraftment and passage of leukemia in SCID mice. Five of seven xenograft leukemias showed significant inhibition in vitro by huIL-4 at concentrations as low as 0.5 ng/mL; furthermore, huIL-4 counteracted the proliferative effects of IL-7. When used to treat two human leukemias engrafted in SCID mice, huIL-4 200 microgram/kg/d, as a continuous 14-day subcutaneous infusion, suppressed the appearance of circulating lymphoblasts and extended survival of mice by 39% and 108%, respectively, the first demonstration of IL-4 activity against human leukemia in vivo. The mean steady-state huIL-4 level in mouse plasma during the infusion was 1.46 ng/mL (SEM +/- 0.14 ng/mL), which was similar to concentrations found to be effective in vitro. ALL cells obtained from mice relapsing after huIL-4 treatment continued to show inhibition by the cytokine in vitro. These data suggest that IL-4 may be useful in the treatment of patients with ALL. 相似文献
90.
Taryar M. Zaw Whitney B. Pope Timothy F. Cloughesy Albert Lai Phioanh L. Nghiemphu Benjamin M. Ellingson 《Journal of neuro-oncology》2014,116(3):601-608
Cell invasion, motility, and proliferation level estimate (CIMPLE) mapping is a new imaging technique that provides parametric maps of microscopic invasion and proliferation rate estimates using serial diffusion MRI data. However, a few practical constraints have limited the use of CIMPLE maps as a tool for estimating these dynamic parameters, particularly during short-interval follow-up times. The purpose of the current study was to develop an approximation for the CIMPLE map solution for short-interval scanning involving the assumption that net intervoxel tumor invasion does not occur within sufficiently short time frames. Proliferation rate maps created using the “no invasion” approximation were found to be increasingly similar to maps created from full solution during increasingly longer follow-up intervals (3D cross correlation, R 2 = 0.5298, P = 0.0001). Results also indicate proliferation rate maps from the “no invasion” approximation had significantly higher sensitivity (82 vs. 64 %) and specificity (90 vs. 80 %) for predicting 6 month progression free survival and was a better predictor of time to progression during standard radiochemotherapy compared to the full CIMPLE solution (log-rank; no invasion estimation, P = 0.0134; full solution, P = 0.0555). Together, results suggest the “no invasion” approximation allows for quick estimation of proliferation rate using diffusion MRI data obtained from multiple scans obtained daily or biweekly for use in quantifying early treatment response. 相似文献