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61.
Previous studies at an oil refinery in Saint John, New Brunswick, Canada, found a diminished fish community downstream of the effluent outfall that appeared to be associated with periodic low dissolved oxygen concentrations due to episodic discharges of contaminated transport vessel ballast water. This study was initiated after the ballast water was removed from the effluent to further investigate the potential causes of residual effects in the study stream, Little River. We used field caging of fish, laboratory bioassays, and chemical analysis of effluents and sediments from the field site to determine if the effluent or contaminated sediments were affecting the recovery of the fish community in Little River. The field studies suggested that exposed, caged fish were affected, displaying >40 % increases in liver sizes and increased liver detoxification enzyme activity (cytochrome P450 1A, CYP1A); however, similar responses were absent in laboratory exposures that used effluent only. Adding sediments collected from the vicinity of the refinery’s outfall to the laboratory bioassays reproduced some of the field responses. Chemical analyses showed high concentrations of PAHs in sediments but low concentrations in the effluent, suggesting that the PAHs in the sediment were contributing more to the impacts than the effluent. Application of effects-based monitoring is suggested as beneficial to identify impacts to fisheries where refinery effluents of this type are involved.  相似文献   
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Grover disease (GD) is an idiopathic dermatosis that typically manifests as itchy papules over the trunk in middle‐aged men. Bullous pemphigoid (BP) is an autoimmune bullous disease that affects older people. Not only are the two diseases easily distinguishable on clinical grounds, they are also characterized by differences in histopathology, pathogenesis and response to treatment Thus, the co‐occurrence of these two conditions in the same patient is usually considered coincidental. In this report, we present a multicentre retrospective analysis of six patients who developed both GD and BP over a short period of time, and in all cases but one, GD preceded BP. We discuss the clinical and histopathological features of these patients, and the suggested mechanisms of the diseases. We conclude that GD might predispose to the development of BP.  相似文献   
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The purpose of this study was to examine the extent to which distinct patterns of fidelity of implementation emerged for 5331 schools over a 5-year course of implementing school-wide positive behavioral interventions and supports (SWPBIS). We used latent class analysis to classify schools based on their likelihood of implementing SWPBIS with fidelity each year, then assessed school and district predictors of classifications. A four-class solution fit the model well, with two patterns of sustained implementation (Sustainers and Slow Starters) and two patterns of practice abandonment (Late Abandoners and Rapid Abandoners). Significant predictors of group membership included grade levels served, enrollment, proportion of schools implementing SWPBIS in the district (“critical mass”), and size of the implementation cohort (“community of practice”). Elementary schools, larger schools, schools in districts with more schools already implementing SWPBIS, and those starting within a larger initial district cohort were more likely to be in the sustaining classes. Results are discussed in terms of understanding patterns of implementation in schools to enhance sustained implementation of school practices.  相似文献   
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