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Denise Frawley Selina McCoy Joanne Banks Maeve Thornton 《Child indicators research》2014,7(4):843-859
Internationally and in Ireland, much of the research around gender and educational engagement has centred on the academic differences between boys and girls (Warrington and Younger 2000; Francis 2009; O’Connor 2007). Less is known however about the factors shaping affective school engagement and student self-concept and how this can affect participation in learning. Children and young people emphasise the affective or emotional as much as the learning aspects of school life (Alexander 2008). Drawing on data from the 9-year cohort of the Growing Up in Ireland study, this paper examines self-concept among boys and girls in Irish primary schools. The findings show important differences in terms of the affective elements of school engagement, with boys more likely than girls to score significantly lower levels on measures of ‘good’ behaviour and intellectual school status, while girls score significantly lower on freedom from anxiety than boys. The findings also illustrate that predictors of disengagement are about more than the child’s gender – in that working class children and students with special educational needs are faring less well in terms of affective engagement in school. 相似文献
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Measuring dental drift and orthodontic tooth movement in response to various initial forces in adult rats 总被引:13,自引:0,他引:13
G J King S D Keeling E A McCoy T H Ward 《American journal of orthodontics and dentofacial orthopedics》1991,99(5):456-465
A method for the quantification of orthodontic tooth movement in the rat is presented. Reliability, sensitivity, and validity were assessed and tooth movement kinetics were determined for initial forces of 20, 40, and 60 gm. The appliance consisted of a 9 mm length of closed coil spring suspended between a cleat and bonded to the occlusal surface of the maxillary first molars and the maxillary incisors. Initial tipping forces were placed by suspending known weights from the anterior end of these coils before fixation to the incisors. Tooth movement was quantified from enlarged cephalograms by measuring the position of a reproducible landmark on the molar cleat with respect to either zygomatic amalgam implants or a barbed broach placed submucosally on the palate. All measurements were made along the molar-incisor vector by projecting at 90 degrees to this line. Validity and sensitivity were assessed by quantifying molar distal drift and comparing these results with reports of bone turnover rates adjacent to distally drifting adult rat molars. Reliability was obtained by estimating the error of a single measurement in a longitudinal study of 12 adult male Sprague-Dawley rats (180 to 200 days) receiving both amalgam and broach implants and a cross-sectional study of 72 animals divided equally into six groups to be killed at 1, 3, 5, 7, 10, and 14 days. No orthodontic forces were used in this portion of the study. Implant stability within the craniofacial complex was assessed by measuring bilateral broaches as a function of time with respect to each other. There were no systematic errors between replicate films for either the amalgam or the broach method. The 95% confidence limit for a single determination of molar position was 62 microns using the amalgams and 47 microns for the broach (p less than 0.001). The latter could be reduced to 23 microns when the average of four independent determinations was used. Homologous implants did not differ with respect to each other in the sagittal plane but did in the transverse plane (p less than 0.01), migrating laterally 9 microns/day. Linear regression analysis of molar distal movement over time predicted 7.7 microns/day distal drift (p less than 0.01), which compared favorably with reports of 6.7 microns/day of alveolar bone turnover during this drifting process. Characteristic three-part cumulative tooth movement kinetics were obtained for the 40 and 60 gm initial force groups. No individual time point at 60 gm differed from its counterpart at 40 gm.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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On the longevity of teeth 总被引:2,自引:0,他引:2
G McCoy 《The Journal of oral implantology》1983,11(2):248-267
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Jack E. Steiner Garrett N. McCoy Christopher P. Hess William B. Dobyns Denise W. Metry Beth A. Drolet Mohit Maheshwari Dawn H. Siegel 《American journal of medical genetics. Part A》2018,176(1):48-55
PHACE syndrome is the association of segmental facial hemangiomas with congenital arterial, brain, cardiac, and ocular anomalies. Structural brain malformations affect 41–52% of PHACE patients and can be associated with focal neurologic deficits, developmental delays, and/or intellectual disability. To better characterize the spectrum of structural brain and other intracranial anomalies in PHACE syndrome, MRI scans of the head/neck were retrospectively reviewed in 55 patients from the PHACE Syndrome International Clinical Registry and Genetic Repository. All registry patients with a diagnosis of definite PHACE syndrome who had MRI scans of satisfactory quality were included. Of 55 patients, 34 (62%) demonstrated ≥1 non‐vascular intracranial anomaly; structural brain malformations were present in 19 (35%). There was no difference in the prevalence of brain anomalies between genders. Brain anomalies were more likely in patients with S1 and/or S2 distribution of facial hemangioma. The most common structural brain defects were cerebellar hypoplasia (25%) and fourth ventricle abnormalities (13%). Dandy–Walker complex and malformations of cortical development were present in 9% and 7%, respectively. Extra‐axial findings such as pituitary anomalies (18%) and intracranial hemangiomas (18%) were also observed. Six patients (11%) had anomalies of the globes or optic nerve/chiasm detectable on MRI. Brain malformations comprise a diverse group of structural developmental anomalies that are common in patients with PHACE syndrome. Along with brain malformations, numerous abnormalities of the pituitary, meninges, and globes were observed, highlighting the need for careful radiologic assessment of these structures in the neuroimaging workup for PHACE syndrome. 相似文献
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Harald Renz Becky D. Adkins Sina Bartfeld Richard S. Blumberg Donna L. Farber Johan Garssen Peter Ghazal David J. Hackam Benjamin J. Marsland Kathy D. McCoy John Penders Immo Prinz Valerie Verhasselt Erika von Mutius Jeffrey N. Weiser Duane R. Wesemann Mathias W. Hornef 《The Journal of allergy and clinical immunology》2018,141(4):1212-1214
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Background
This report describes two cases with unexplained positive results for phencyclidine (PCP).Aims
This case will correlate lamotrigine (Lamictal®) use with false-positive results for PCP on a rapid urine toxicology screen.Methods
Case 1: A 62-year-old male arrived to the emergency department in extreme psychosis. All positive results on the urine drug screen could be accounted for except PCP. A comprehensive drug screen was performed to confirm PCP use, but returned negative. PCP was ruled out as the causative agent. The reason for the PCP false positive remained unknown. Case 2: A 49-year-old female presented to the ED with a history of seizures and depression. Despite positive PCP results on a rapid urine drug screen, PCP use was ruled out due to patient presentation and comprehensive history.Results
The differential diagnosis in case 1 included PCP abuse until PCP was ruled out by a comprehensive drug screen. A literature search failed to explain a reason for false-positive results. The patient in case 2 was not psychotic, but returned a positive urinalysis result for PCP. Case 2’s presentation combined with a comprehensive history at the facility ruled out PCP use. Both patients were taking the anti-seizure medication lamotrigine with nothing else in common.Conclusion
Lamotrigine has the potential to cause false-positive results for PCP on the Bio-Rad TOX/See urine toxicology screen. 相似文献10.
K W Miller K K Chan H G McCoy R P Fischer W G Lindsay D E Zaske 《Clinical pharmacology and therapeutics》1979,26(1):54-62
Cephalothin kinetics was studied in 5 patients the day before (PREOP), during (SURG), and the day after (POSTOP) cardiopulmonary bypass surgery. The PREOP (114 ml/min) and SURG (94 ml/min) renal clearances were of the same order but both were less than POSTOP renal clearance (248 ml/min). Cephalothin total body clearance during operation was lower (p less than 0.01) than PREOP or POSTOP clearance, with decreased metabolic clearance the primary cause. There was reduction in cephalothin elimination throughout the surgical procedure, not only in the period of extracorporeal circulation, indicating that general anesthesia had a significant influence on drug disposition. The metabolite deacetylcephalothin was rapidly formed on all 3 days and its kinetic behavior paralleled that of the parent drug. 相似文献