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排序方式: 共有482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94.
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95.
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
96.
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
97.
Survival in HIV‐infected patients with lymphoma according to the choice of antiretroviral treatment: an observational multicentre study
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98.
Floor WT Vergouwe Madeleine Gottrand Bas PL Wijnhoven Hanneke IJsselstijn Guillaume Piessen Marco J Bruno René MH Wijnen Manon CW Spaander 《World journal of gastroenterology : WJG》2018,24(9):1056-1062
Esophageal atresia(EA) is one of the most common congenital digestive malformations and requires surgical correction early in life. Dedicated centers have reported survival rates up to 95%. The most frequent comorbidities after EA repair are dysphagia(72%) and gastroesophageal reflux(GER)(67%). Chronic GER after EA repair might lead to mucosal damage, esophageal stricturing, Barrett's esophagus and eventually esophageal adenocarcinoma. Several long-term follow-up studies found an increased risk of Barrett's esophagus and esophageal carcinoma in EA patients, both at a relatively young age. Given these findings, the recent ESPGHAN-NASPGHAN guideline recommends routine endoscopy in adults born with EA. We report a series of four EA patients who developed a carcinoma of the gastrointestinal tract: three esophageal carcinoma and one colorectal carcinoma in a colonic interposition. These cases emphasize the importance of lifelong screening of the upper gastrointestinal tract in EA patients. 相似文献
99.
Homer R. Wolfe Wenatchee Wash William F. Durham PhD Perrine Fla John F. Armstrong 《Archives of environmental & occupational health》2013,68(6):711-716
The urinary excretion of p-nitrophenol and of dichlorodiphenylacetic acid (DDA) was measured in spraymen applying fo·rmulations containing both parathion and DDT" In each instance, excretory level of metabolite correlated well with exposure to the pesticide. Para-nitrophenol excretion levels showed changes of greater magnitude in response to a specific exposure than did DDA excretion. However, in general the excretory patterns for p-nitrophenol and DCA were similar. Both metabolites reached peak levels at about the same time interval (p-nitrophenol, 8m7 hours; DCA, 10m1 hours) after exposure beganm Excretion of both p-nitrophenol and DDA tended to increase with an increase in ambient temperature. Excretion curves for both metabolites showed diurnal variation during the period after exposure had ended. On the average for a specific exposure, more parathion-derived material than DDTderived material was recovered in the urine. 相似文献
100.
Aetiological factors for oral manifestations of HIV 总被引:2,自引:0,他引:2
GD Palmer PG Robinson SJ Challacombe W Birnbaum D Croser PL Erridge T Hodgson D Lewis A McLaren JM Zakrzewska 《Oral diseases》1996,2(3):193-197
OBJECTIVES: Describe the oral diseases in HIV-infected individuals in London, UK and identify social and medical factors related to the presence of specific oral diseases.
DESIGN: Cross-sectional analytic study.
SETTING: Dental clinics.
SUBJECTS: Consecutive sample of 456 patients with HIV infection.
METHODS: Social and medical history and clinical examinations. Univariate and logistic regression analysis.
OUTCOMES: Presence of HIV-associated oral disease.
RESULTS: 80% of patients with AIDS and 50% of patients with HIV had a specific oral disease. The most common diseases were hairy leukoplakia (30%), erythematous candidiasis (24%), pseudomembranous candidiasis (14%), angular chielitis (6%), necrotising periodontal disease (8%) and non-recurrent ulceration (6%).
CONCLUSIONS: The presence of erythematous candidiasis was not related to advanced HIV disease. Pseudomembranous candidiasis, hairy leukoplakia and mucosal ulceration were significantly associated with advanced HIV disease. Smoking was also identified as a strong aetiological factor in oral diseases. Longitudinal studies are required to further explore the prognostic significance of oral diseases in HIV infection. 相似文献
DESIGN: Cross-sectional analytic study.
SETTING: Dental clinics.
SUBJECTS: Consecutive sample of 456 patients with HIV infection.
METHODS: Social and medical history and clinical examinations. Univariate and logistic regression analysis.
OUTCOMES: Presence of HIV-associated oral disease.
RESULTS: 80% of patients with AIDS and 50% of patients with HIV had a specific oral disease. The most common diseases were hairy leukoplakia (30%), erythematous candidiasis (24%), pseudomembranous candidiasis (14%), angular chielitis (6%), necrotising periodontal disease (8%) and non-recurrent ulceration (6%).
CONCLUSIONS: The presence of erythematous candidiasis was not related to advanced HIV disease. Pseudomembranous candidiasis, hairy leukoplakia and mucosal ulceration were significantly associated with advanced HIV disease. Smoking was also identified as a strong aetiological factor in oral diseases. Longitudinal studies are required to further explore the prognostic significance of oral diseases in HIV infection. 相似文献