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Background: In order to better understand the recent rise in nonprescribed use of psychostimulants on college campuses, motives, outcomes, and acceptability of nonprescribed psychostimulants have been evaluated. Despite knowledge that students use nonprescribed medical stimulants for improved academic performance and recreational use, gender differences in these motives have not been examined, despite the fact that the social construction of gender may well affect motives for use. Objectives: The goal of the present study was to examine gender differences in motives, outcomes, and acceptability of nonprescribed psychostimulant use. Methods: 2716 undergraduates (1448 male) between the ages of 17 and 57 years (M = 19.43 years, SD = 1.7 years) completed an online survey examining subjective motives of nonprescribed psychostimulant use, as well as behaviors after use and moral views of nonprescribed use. Results: Consistent with hypotheses and known gender differences in social motivation, results suggested that while females are more likely to use nonprescribed psychostimulants for reasons related to schoolwork, males are typically more likely to use psychostimulants for reasons related to partying and socializing. Additional gender differences were that males are more likely to take part in other risky behaviors after use of psychostimulants, as well as view nonprescribed use as more moral and less physically dangerous than females. Conclusions/Importance: This work suggests that there are striking gender differences in motivation and outcomes of use of nonprescribed psychostimulants, which may have implications for personalized approaches for prevention of nonprescribed psychostimulant use on campuses based on gender. 相似文献
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Romina Mizrahi Ivonne Suridjan Miran Kenk Tony P George Alan Wilson Sylvain Houle Pablo Rusjan 《Neuropsychopharmacology》2013,38(4):673-682
A number of addictions have been linked with decreased striatal dopamine (DA) receptor availability and DA release. Stress has a key role in cannabis craving, as well as in modulation of dopaminergic signaling. The present study aimed to assess DA release in response to a laboratory stress task with [11C]-(+)-PHNO positron emission tomography in cannabis users (CU). Thirteen healthy CU and 12 healthy volunteers (HV) were scanned during a sensorimotor control task (SMCT) and under a stress condition using the validated Montreal imaging stress task (MIST). The simplified reference tissue model (SRTM) was used to obtain binding potential (BPND) in striatal subdivisions: limbic striatum (LST), associative striatum (AST), and sensorimotor striatum (SMST). Stress-induced DA release (indexed as a percentage of reduction in [11C]-(+)-PHNO BP ND) between CU and HV was tested with analysis of variance. SMCT BPND was significantly higher in CU compared with HV in the AST (F=10.38, p=0.003), LST (F=4.95, p=0.036), SMST (F=4.33, p=0.048), and whole striatum (F=9.02, p=0.006). Percentage of displacement (change in BPND between SMCT and MIST PET scans) was not significantly different across groups in any brain region, except in the GP (−5.03±14.6 in CU, compared with 6.15±12.1 in HV; F=4.39, p=0.049). Duration of cannabis use was significantly associated with stress-induced [11C]-(+)-PHNO displacement by endogenous DA in the LST (r=0.566, p=0.044), with no effect in any other brain region. In conclusion, despite an increase in striatal BPND observed during the control task, chronic cannabis use is not associated with alterations in stress-induced DA release. 相似文献
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Romaric Loffroy Sylvain Favelier Pierre Pottecher Pierre-Yves Genson Louis Estivalet Sophie Gehin Jean-Pierre Cercueil Denis Krausé 《World journal of radiology》2015,7(7):143-148
Visceral artery aneurysms (VAA) include splanchnic and renal artery aneurysms. They represent a rare clinical entity, although their detection is rising due to an increased use of cross-sectional imaging. Rupture is the most devastating complication, and is associated with a high morbidity and mortality. In addition, increased percutaneous endovascular interventions have raised the incidence of iatrogenic visceral artery pseudoaneurysms (VAPAs). For this reason, elective repair is preferable in the appropriately chosen patient. Controversy still exists regarding their treatment. Over the past decade, there has been steady increase in the utilization of minimally invasive, non-operative interventions, for vascular aneurysmal disease. All VAAs and VAPAs can technically be fixed by endovascular techniques but that does not mean they should. These catheter-based techniques constitute an excellent approach in the elective setting. However, in the emergent setting it may carry a higher morbidity and mortality. The decision for intervention has to take into account the size and the natural history of the lesion, the risk of rupture, which is high during pregnancy, and the relative risk of surgical or radiological intervention. For splanchnic artery aneurysms, we should recognize that we are not, in reality, well informed about their natural history. For most asymptomatic aneurysms, expectant treatment is acceptable. For large, symptomatic or aneurysms with a high risk of rupture, endovascular treatment has become the first-line therapy. Treatment of VAPAs is always mandatory because of the high risk of rupture. We present our point of view on interventional radiology in the splanchnic arteries, focusing on what has been achieved and the remaining challenges. 相似文献
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Marie Gauthier Melanie Vincent Sylvain Morneau Isabelle Chevalier 《European journal of pediatrics》2012,171(12):1839-1844
Acute bronchiolitis has been associated with an increasing hospitalization rate over the past decades. The aim of this paper was to estimate the impact of home oxygen therapy (HOT) on hospital stay for infants with acute bronchiolitis. A retrospective cohort study was done including all children aged ??12?months discharged from a pediatric tertiary-care center with a diagnosis of bronchiolitis, between November 2007 and March 2008. Oxygen was administered according to a standardized protocol. We assumed children with the following criteria could have been sent home with O2, instead of being kept in hospital: age ??2?months, distance between home and hospital <50?km, in-hospital observation ??24?h, O2 requirement ??1.0?L/min, stable clinical condition, no enteral tube feeding, and intravenous fluids <50?mL/kg/day. Children with significant underlying disease were excluded. A total of 177 children were included. Median age was 2.0?months (range 0?C11), and median length of stay was 3.0?days (range 0?C18). Forty-eight percent of patients (85/177) received oxygen during their hospital stay. Criteria for discharge with HOT were met in 7.1?% of patients, a mean of 1.8?days (SD 1.8) prior to real discharge. The number of patient-days of hospitalization which would have been saved had HOT been available was 21, representing 3.0?% of total patient-days of hospitalization for bronchiolitis over the study period (21/701). Conclusions: In this study setting, few children were eligible for an early discharge with HOT. Home oxygen therapy would not significantly decrease the overall burden of hospitalization for bronchiolitis. 相似文献
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