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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86.
Rapezzi C Quarta CC Guidalotti PL Longhi S Pettinato C Leone O Ferlini A Salvi F Gallo P Gagliardi C Branzi A 《European journal of nuclear medicine and molecular imaging》2011,38(3):470-478
Purpose
We previously reported in a small series of patients that 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) scintigraphy tested positive in transthyretin-related (TTR) (both mutant and wild-type) but not in primary (AL) amyloidotic cardiomyopathy (AC). We extended our study to a larger cohort of patients with AC.Methods
We evaluated (1) 45 patients with TTR-related AC (28 mutant and 17 wild-type), (2) 34 with AL-related AC and (3) 15 non-affected controls. Myocardial uptake of 99mTc-DPD (740?MBq i.v.) was semiquantitatively and visually assessed at 5?min and at 3?h.Results
Heart retention (HR) and heart to whole-body retention ratio (H/WB) of late 99mTc-DPD uptake were higher among TTR-related AC (HR 7.8%; H/WB 10.4) compared with both unaffected controls (HR 3.5%; H/WB 5.7; p?0.0001) and AL-related AC (HR 4.0%; H/WB 6.1; p?0.0001). For the diagnosis of TTR-related AC, positive and negative predictive accuracy of visual scoring of cardiac retention were: 80 and 100% (visual score ??1); 88 and 100% (visual score ??2); and 100 and 68% (visual score = 3). At adjusted linear regression analysis, TTR aetiology turned out to be the only positive predictor of increasing 99mTc-DPD uptake in terms of both HR [?? 2.5, 95% confidence interval (CI) 1.5?C3.5; p?0.0001] and H/WB (?? 3.5, 95% CI 2.1?C4.9; p?0.0001).Conclusion
While 99mTc-DPD scintigraphy was confirmed to be useful for differentiating TTR from AL-related AC, diagnostic accuracy was lower than previously reported due to a mild degree of tracer uptake in about one third of AL patients. 99mTc-DPD scintigraphy can provide an accurate differential diagnosis in cases of absent or intense uptake evaluated by visual score. 相似文献87.
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88.
Rapezzi C Guidalotti P Salvi F Riva L Perugini E 《Journal of the American College of Cardiology》2008,51(15):1509-10; author reply 1510
89.
PL Perrotta ; L Baril ; C Tead ; J Chapman ; D Dincecco ; DH Buchholz ; EL Snyder 《Transfusion》1999,39(1):63-69
BACKGROUND: Photochemical methods can effectively inactivate extracellular viruses and bacteria found in blood components. Treatment of plasma with methylene blue (MB), a phenothiazine dye, and visible light inactivates enveloped viruses including HIV-1. The effects of MB- treated plasma on cellular components stored in vitro have not been well characterized. STUDY DESIGN AND METHODS: MB-treated plasma (83 microg MB/250 mL plasma) was added to single-donor platelets, stored AS- 1 red cells (RBCs), irradiated RBCs, and frozen-deglycerolized RBCs. In vitro platelet assays performed after 1 and 5 days of storage in MB- treated plasma included pH, pO2, pCO2, HCO3, platelet number, lactate dehydrogenase, glucose, osmotic recovery, and CD62 expression. RBC components were examined at specific intervals for leakage of potassium, plasma hemoglobin level, and percentage of hemolysis. Direct antiglobulin tests, osmotic fragilities, and RBC antigen stability tests were also performed on RBCs stored in MB-treated plasma. Components stored with autologous plasma or nontreated allogeneic plasma served as controls. RESULTS: Similar storage-induced changes in pH, glucose, and platelet numbers, as well as increases in lactate dehydrogenase, CD62 expression, and lactate were seen in single-donor platelets stored with MB-treated and control plasma. Platelet morphology scores and osmotic recoveries were not altered. Plasma hemoglobin and potassium and percentage of hemolysis increased equally in the various RBC components stored with MB-treated or nontreated plasma. Osmotic fragility and RBC antigen stability were not appreciably altered by MB-treated plasma. CONCLUSION: Plasma treated by MB photoinactivation can be used for in vitro resuspension and storage of platelets or RBCs, because of the lack of influence of MB-treated plasma on a variety of in vitro platelet and RBC assays. 相似文献
90.
PTEN is inversely correlated with the cell survival factor Akt/PKB and is inactivated via multiple mechanismsin haematological malignancies 总被引:8,自引:1,他引:7