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排序方式: 共有1443条查询结果,搜索用时 15 毫秒
71.
Cholangiocarcinoma: the "other" liver cancer on the rise 总被引:1,自引:0,他引:1
72.
Chen Du Mary Adjepong Megan Chong Hueh Zan Min Jung Cho Jenifer I. Fenton Pao Ying Hsiao Laura Keaver Heesoon Lee Mary-Jon Ludy Wan Shen Winnie Chee Siew Swee Jyothi Thrivikraman Felicity Amoah-Agyei Emilie de Kanter Wenyan Wang Robin M. Tucker 《Nutrients》2022,14(5)
Background: Obesity is a growing epidemic among university students, and the high levels of stress reported by this population could contribute to this issue. Singular relationships between perceived stress; engagement in restrained, uncontrolled, and emotional eating; sleep; dietary risk; and body mass index (BMI) have been reported in the current body of literature; however, these constructs interact with each other, and the complex relationships among them are infrequently examined. Therefore, the aim of the present study was to explore the complex relationships between these constructs using mediation and moderation analyses stratified by gender. Methods: A cross-sectional study, enrolling university students from the United States (U.S.), the Netherlands, South Korea, Malaysia, Ireland, Ghana, and China, was conducted between October 2020 and January 2021 during the COVID-19 pandemic. Perceived stress; maladaptive eating behaviors including restrained, uncontrolled, and emotional eating; sleep duration and quality; dietary risk; and BMI were assessed using validated questionnaires, which were distributed through an online platform. Results: A total of 1392 students completed the online survey (379 male, 973 female, and 40 who self-identified as “other”). Uncontrolled and emotional eating mediated the relationship between perceived stress and dietary risk for both males and females; higher sleep quality weakened this relationship among female students but not males. Emotional eating mediated the relationship between perceived stress and BMI for both males and females, but higher sleep quality weakened this relationship only among females. Conclusions: Our findings suggest that students in higher education are likely to benefit from interventions to reduce uncontrolled and emotional eating. Programs that improve sleep quality, especially during highly stressful periods, may be helpful. 相似文献
73.
74.
Anterior teeth may have aberrant anatomical variations in the number of roots and root canals. A review of the literature was conducted using appropriate key words in major endodontic journals to identify the available reported cases as well as experimental and clinical investigations on accessory roots and root canals in anterior teeth. After retrieving the full text of related articles, cross‐citations were identified, and the pooled data were then discussed. Results revealed a higher prevalence in accessory root/root canal variations in mandibular anterior teeth than in maxillary counterparts. However, maxillary incisor teeth revealed the highest tendency for accessory root/root canal aberrations caused by anomalies such as dens invaginatus and palato‐gingival groove. Primary anterior teeth may also exhibit external and internal anatomical variations in the root, especially maxillary canines. Therefore, dental practitioners should thoroughly assess all teeth scheduled for root canal treatment to prevent the undesirable consequences caused by inadequate debridement of accessory configurations of the root canal system. 相似文献
75.
Hala E. Hashem Manal R. Abd El-Haleem Mona G. Amer Ashraf Bor’i 《Ultrastructural pathology》2017,41(5):346-357
Oxidative stress is one mechanism involved in the pathogenesis of ischemia/reperfusion (/R) retinal injury. The histological, biochemical, and functional changes associated with pomegranate (PMG) treatment prior to retinal I/R were analyzed using 40 adult male albino rats. Rats were divided into four groups: Groups I and II (sham operated and received saline or PMG, respectively); Groups III and IV (I/R rat models with prior administration of saline or 250 mg/kg/day PMG, respectively). Electroretinogram (ERG) results were recorded and eye specimens were taken and processed for light and electron microscopic examinations and for assessment of oxidative status in retinal homogenate. I/R lead to degenerative changes in retinal layers with a significant reduction in nuclear factor erythroid 2-related factor 2 (Nrf2) immunoreactivity in concomitant with significant oxidant–antioxidant disturbance and decreased a- and b-wave amplitude in the ERG. These alterations were ameliorated with prior PMG treatment. In conclusion, PMG treatment, as an antioxidant, attenuated retinal structural and functional I/R injury through activation of Nrf2 which could be a base for future therapy designs. 相似文献
76.
We evaluated two putative moderators of treatment outcome as well as the role of Headache Management Self-Efficacy (HMSE) in mediating treatment outcomes in the drug and non-drug treatment of chronic tension-type headache (CTTH). Subjects were 169 participants (M = 38 yrs.; 77% female; M headache days/mo. = 22) who received one of four treatments in the treatment of CTTH trial (JAMA, 2001; 285: 2208–15): tricyclic antidepressant medication, placebo, (cognitive-behavioral) stress-management therapy plus placebo, and stress-management therapy plus antidepressant medication. Severity of CTTH disorder and the presence of a psychiatric (mood or anxiety) disorder were found to moderate outcomes obtained with the three active treatments and with placebo, as well as to moderate the role of HMSE in mediating improvements. Both moderator effects appeared to reflect the differing influence of the moderator variable on each of the three active treatments, as well as the fact that the moderator variables exerted the opposite effect on placebo than on the active treatments. HMSE mediated treatment outcomes in the two stress-management conditions, but the pattern of HMSE mediation was complex, varying with the treatment condition, the outcome measure, and the moderator variable. Irrespective of the severity of the CTTH disorder HMSE fully mediated observed improvements in headache activity in the two stress-management conditions. However, for patients with a mood or anxiety disorder HMSE only partially mediated improvements in headache disability, suggesting an additional therapeutic mechanism is required to explain observed improvements in headache disability in the two stress-management conditions. 相似文献
77.
Summary This paper introduces the concepts of time‐specific weak and strong cross‐section dependence, and investigates how these notions are related to the concepts of weak, strong and semi‐strong common factors, frequently used for modelling residual cross‐section correlations in panel data models. It then focuses on the problems of estimating slope coefficients in large panels, where cross‐section units are subject to possibly a large number of unobserved common factors. It is established that the common correlated effects (CCE) estimator introduced by Pesaran remains asymptotically normal under certain conditions on factor loadings of an infinite factor error structure, including cases where methods relying on principal components fail. The paper concludes with a set of Monte Carlo experiments where the small sample properties of estimators based on principal components and CCE estimators are investigated and compared under various assumptions on the nature of the unobserved common effects. 相似文献
78.
Oxidative stress significantly contributes to cisplatin (CP)-associated cytotoxicity, and use of antioxidants could counteract such cytotoxic effects of CP. The major biochemical pathway for reactive oxygen species (ROS) formation proceeds through O2− production, which is generated by NADPH oxidase, such oxidative stress can activate p38 MAPK to intensify the cytotoxic effect of CP. We mainly aimed to study the protective effect of oxytocin (OT) on CP-induced nephrotoxicity whereas; it was previously shown to have anti-inflammatory effects in different inflammation models. Administration of OT significantly decreased the gene expression of both NADPH oxidase and P38 MAPK, nitric oxide (NO), myloperoxidase (MPO), and TBARS, furthermore it increased the renal tissue levels of antioxidants; reduced glutathione (GSH), and superoxide dismutase (SOD). Histologically, OT reduced the monocellular infiltration as well as the tubular damage in CP-induced nephrotoxicity. In conclusion OT has a powerful antioxidant effect that can alleviate the CP-induced nephrotoxicity through inhibition of NADPH oxidase and P38 MAPK resulting in improvement of kidney functions. 相似文献
79.
Blythe A. Corbett Joan R. Gunther Dan Comins Jenifer Price Niles Ryan David Simon Clayton W. Schupp Taylor Rios 《Journal of autism and developmental disorders》2011,41(4):505-511
The pilot investigation evaluated a theatrical intervention program, Social Emotional NeuroScience Endocrinology (SENSE) Theatre,
designed to improve socioemotional functioning and reduce stress in children with autism spectrum disorder (ASD). Eight children
with ASD were paired with typically developing peers that served as expert models. Neuropsychological, biological (cortisol
and oxytocin), and behavioral measures were assessed in a pretest–posttest design. The intervention was embedded in a full
musical theatrical production. Participants showed some improvement in face identification and theory of mind skills. The
intervention shows potential promise in improving the socioemotional functioning in children with ASD through the utilization
of peers, video and behavioral modeling, and a community-based theatrical setting. 相似文献
80.
David B. Henry Allison Dymnicki Candice Kane Elena Quintana Jenifer Cartland Kimberly Bromann Shaun Bhatia Elise Wisnieski 《Prevention science》2014,15(4):437-447
Predictive epidemiology is an embryonic field that involves developing informative signatures for disorder and tracking them using surveillance methods. Through such efforts assistance can be provided to the planning and implementation of preventive interventions. Believing that certain minor crimes indicative of gang activity are informative signatures for the emergence of serious youth violence in communities, in this study we aim to predict outbreaks of violence in neighborhoods from pre-existing levels and changes in reports of minor offenses. We develop a prediction equation that uses publicly available neighborhood-level data on disorderly conduct, vandalism, and weapons violations to predict neighborhoods likely to have increases in serious violent crime. Data for this study were taken from the Chicago Police Department ClearMap reporting system, which provided data on index and non-index crimes for each of the 844 Chicago census tracts. Data were available in three month segments for a single year (fall 2009, winter, spring, and summer 2010). Predicted change in aggravated battery and overall violent crime correlated significantly with actual change. The model was evaluated by comparing alternative models using randomly selected training and test samples, producing favorable results with reference to overfitting, seasonal variation, and spatial autocorrelation. A prediction equation based on winter and spring levels of the predictors had area under the curve ranging from .65 to .71 for aggravated battery, and .58 to .69 for overall violent crime. We discuss future development of such a model and its potential usefulness in violence prevention and community policing. 相似文献