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111.
Perianal findings in prepubertal children selected for nonabuse: a descriptive study 总被引:6,自引:0,他引:6
The results of the perianal portion of a project designed to collect normative data of the anogenital anatomy from a representative sample of prepubertal children is presented. A total of 318 children were examined by three physicians from a child sexual abuse evaluation program. After screening for the onset of puberty and the possibility of undetected abuse, 267 subjects remained. The sample included 161 girls and 106 boys ranging in age from 2 months to 11 years. The perianal findings that were encountered with the greatest frequency included erythema (41%), increased pigmentation (30%), and venous engorgement (52%) after two minutes in the knee-chest position. Wedge-shaped smooth areas in the midline, with or without depressions, were found both anterior and posterior to the anus in 26% of the children. Anal skin tags/folds were discovered anterior to the anus in 11%. In 49% of the children there was some dilatation of the anus which opened and closed intermittently in 62%. Flattening of the anal verge and rugae occurred during dilatation by the midpoint of the examination in 44% and 34%, respectively. Perianal findings that were found infrequently in all subgroups included skin tags/folds (0%) and scars (1%) outside the midline, anal dilatation greater than 20 mm without the presence of stool in the rectal ampulla (1.2%), irregularity of the anal orifice after complete dilatation (3%), and prominence of the anal verge (3%). No abrasions, hematomas, fissures, or hemorrhoids were encountered. Less commonly detected findings within specific subgroups included perianal erythema in girls (32%) as compared to boys (57%), pigmentation in the lighter skinned white children (22%) when compared to black (53%) and Hispanic (58%) children, and venous congestion at the beginning of the examination (7%) when compared to the same findings after four minutes in the knee-chest position (73%). There were no perianal skin tags/folds found in the boys. The relatively high incidence of perianal soft tissue changes that were found in this study, when compared to the frequency of similar observations in children suspected of having been sexually abused, reemphasizes the caution medical examiners must exercise in rendering an opinion as to the significance of medical findings. 相似文献
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Mark G. Simkin William L. Kuechler 《Decision Sciences Journal of Innovative Education》2005,3(1):73-98
Instructors can use both “multiple‐choice” (MC) and “constructed response” (CR) questions (such as short answer, essay, or problem‐solving questions) to evaluate student understanding of course materials and principles. This article begins by discussing the advantages and concerns of using these alternate test formats and reviews the studies conducted to test the hypothesis (or perhaps better described as the hope) that MC tests, by themselves, perform an adequate job of evaluating student understanding of course materials. Despite research from educational psychology demonstrating the potential for MC tests to measure the same levels of student mastery as CR tests, recent studies in specific educational domains find imperfect relationships between these two performance measures. We suggest that a significant confound in prior experiments has been the treatment of MC questions as homogeneous entities when in fact MC questions may test widely varying levels of student understanding. The primary contribution of the article is a modified research model for CR/MC research based on knowledge‐level analyses of MC test banks and CR question sets from basic computer language programming. The analyses are based on an operationalization of Bloom's Taxonomy of Learning Goals for the domain, which is used to develop a skills‐focused taxonomy of MC questions. However, we propose that their analyses readily generalize to similar teaching domains of interest to decision sciences educators such as modeling and simulation programming. 相似文献
115.
Adults are typically required to make values‐based decisions multiple times each day.Why, then, should a discussion of values not be explicit across the college curriculum and intentionally integrated into the cocurriculum? The authors describe a place where the work of values education is widely shared. 相似文献
116.
B.M. Thompson K.P. Ribera G.J. Wingenbach T.A. Vestal 《Journal of Food Science Education》2007,6(2):24-29
ABSTRACT: The purpose of this study was to use a validated instrument to determine the attitudes and knowledge of high school teachers regarding food irradiation, and to determine the correlations among their knowledge and attitudes and certain demographic variables. Knowledge and attitudes about food irradiation were measured in selected high school family and consumer sciences teachers ( n = 121) who taught Food and Nutrition, Food Science and Technology, and/or Food Production Management and Services, via a 24-item instrument with 6 factors. Results revealed these teachers held neutral to positive attitudes about the safety of irradiated foods, their perception of the risk of foodborne illness, and learning about food irradiation, and neutral to negative perceptions of their understanding of food irradiation and their competence to teach about it. These teachers had a moderate knowledge base regarding food irradiation. Teachers' attitudes regarding the safety of food irradiation were positively correlated with their perceived understanding of food irradiation, actual knowledge of it, and competence to teach about it. Their perceived understanding of food irradiation was positively correlated with competence to teach about it, knowledge, and attitudes toward the safety of food irradiation. The only demographic variable correlated with knowledge or attitudes was teachers' previous food irradiation educational experiences. These data suggest the importance of education for family and consumer sciences teachers concerning food irradiation. 相似文献
117.
G. Marimuthu 《Resonance》1996,1(5):40-48
Bats are capable of avoiding obstacles that they encounter, even in complete darkness. This is because they emit ultrasound (high frequency sound) and analyse the echo produced when the sound hits objects on their path. This article describes the hunting flight of bats and how echolocation is useful in prey capture. Prey capture without the aid of echolocation by some bats is also described. 相似文献
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Rajput ZI Hu SH Arijo AG Habib M Khalid M 《Journal of Zhejiang University. Science. B》2005,6(11):1057-1062
INTRODUCTION The world population of buffaloes(Bubalus bubalis)has been estimated at over172million head,more than97%(167.6million)of which are in Asia and the Pacific region,mainly in India(97.7million)and Pakistan(25.5million)(FAO,2004).About98%of buffaloes in the region are raised by small farmers owning less than two hectares of land and less than five buffaloes(Mudgal,1992).In general,the water buffalo is regarded as more productive,healthier and more useful than the cow,especiall… 相似文献
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