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21.
Time perception is a fundamental component of everyday life. Although time can be measured using standard units, the relationship between an individual's experience of perceived time and a standard unit is highly sensitive to context. Stressful and threatening stimuli have been previously shown to produce time distortion effects, such that individuals perceive the stimuli as lasting for different amounts of time as compared to a standard unit. As a highly social species, humans are acutely sensitive to social stressors; however, time distortion effects have not been studied in the context of social stress. We collected psychophysiological (electrocardiogram and impedance cardiography) and time perception data before, during, and after a modified version of the Trier Social Stress Test for 42 participants. Based on prior theories and evidence from the time perception literature, we hypothesized that experiencing a stressful event would result in time distortion. This hypothesis was supported by the data, with individuals on average reproducing short and long duration negative and positive stimuli as lasting longer after experiencing social stress, t(41) = −3.55, p = .001, and t(41) = −4.12, p < .001 for negative stimuli, and t(41) = −2.43, p = .02, and t(41) = −3.07, p = .004 for positive stimuli. However, changes in time perception were largely unrelated to psychophysiological reactivity to social stress. These findings are in line with some other studies of time distortion, and provide evidence for the interoceptive salience model of time perception. Implications for mechanisms of time distortion are discussed.  相似文献   
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Objectives: The aim of this systematic literature review is to study the enabling and hindering factors influencing adherence to asthma treatment among adolescents. Furthermore, it explores the role of caregivers and the healthcare provider in terms of supporting adolescents to manage and live with asthma. Data sources: The literature review was conducted using the MeSH terms asthma, adherence, health literacy, behavior, adolescents, tools, healthcare provider, caregiver, peer influence, self-management, quality of life, morbidity and mortality in PubMed, PsycInfo, MEDLINE and CINAHL. Study selection: The literature search resulted in 652 articles of which 304 were screened based on title and abstracts. Ninety-one of the screened articles were then selected for full-text assessment resulting in 42 articles for in-depth analysis. Results: The literature review identified nine enabling and hindering factors relevant for adherence to asthma treatment among adolescents: behavior, belief, self-management, health literacy, role of health provider, assessment of adherence, role of caregiver, role of peers and the national asthma guidelines. Conclusion: Working with this particular age group is complex and further research in understanding adolescent's behavior, motives, beliefs and perceptions towards adherence to asthma treatment is required to guide them towards better self-management and acceptance of their condition.  相似文献   
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The survival experience of patients with cancer of the larynx (ICD 10) registered by the Bombay population-based cancer registry India, during the years 1992-1994, is described. The vital status of these subjects were established by matching with death certificates from the Bombay Municipal death register and by active methods such as reply-paid postal enquiries, telephone enquiries, scrutiny of case records and house visits. Of the 675 eligible cases for analysis, 458 (67.9%) were dead and 217 (32.1%) were alive at last follow-up. The 5-year observed and relative survival rates were 29.1 and 38.2%, respectively; these were 52.1 and 58.5% for glottic laryngeal cancer and 24.2 and 31.4% for supraglottic laryngeal cancer, respectively. The 5-year observed survival was 53.1% for those with localised cancer and 17.8% for those with regional extension. Advancing age, regional and metastatic disease and supraglottic cancers were associated with significantly reduced survival. Early detection and prompt treatment should improve overall survival from laryngeal cancer.  相似文献   
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Objective

Decline in verbal fluency is the most consistent and persistent cognitive impairment documented after deep brain stimulation of the subthalamic nucleus in Parkinson's disease. The mechanisms of this deficit are unclear. We aimed to identify and characterise verbal fluency related processing within the subthalamic nucleus through analysis of local field potentials.

Methods

Local field potentials were recorded from deep brain stimulation electrodes implanted in the subthalamic nuclei of 8 patients (16 sides) with Parkinson's disease, when patients were on medication. Patients performed phonemic and semantic verbal fluency tasks and a control word repetition task to control for the motor output involved in response generation.

Results

Significant increases in local field potential Power (p ≤ 0.05) were seen across a broad gamma frequency band (30–95 Hz) during both verbal fluency tasks, after controlling for motor output. Increases in gamma local field potential Power of + 7.5% ± 2.3% (SEM) in the semantic fluency task and + 6.9% ± 2.0% in the phonemic fluency task were derived when averaging across all electrode contact pairs. Gamma changes recorded from contacts lying in the left hemisphere (dominant in verbal fluency) correlated with average number of correct responses generated (r = 0.81 p = 0.015) and measures of ‘switching’ (r = 0.79 p = 0.020) particularly strongly in the semantic fluency task.

Interpretation

Frequency specific power changes observed during task performance are consistent with involvement of the subthalamic nucleus in switching during verbal fluency. Antagonism of such task-related activity with high frequency stimulation of this nucleus may explain the impairments reported.  相似文献   
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Morus nigra Linn. (black mulberry) is used in gastrointestinal ailments. This study demonstrates gut modulatory properties of M. nigra. The prokinetic, laxative, and antidiarrheal activities of M. nigra were assessed in mice, while isolated rabbit jejunum and guinea‐pig ileum were used to explore insight into mechanism(s). At 30 and 70 mg/kg, the crude extract of M. nigra (Mn.Cr) exhibited atropine‐sensitive prokinetic and laxative effects, similar to carbachol (CCh). While at higher doses (100, 300, and 500 mg/kg), Mn.Cr offered protection against castor oil‐induced diarrhea. In rabbit jejunum, Mn.Cr and its chloroform fraction inhibited CCh‐induced contractions more potently compared with high K+ (80 mm ). Conversely, petroleum fraction was more potent against high‐K+‐induced contractions. At 0.01 mg/mL, Mn.Cr caused a parallel shift in acetylcholine concentration–response curves (CRCs) followed by a non‐parallel shift at 0.03 mg/mL, similar to dicyclomine. At further tested concentrations, Mn.Cr (0.1 and 0.3 mg/mL) and petroleum fraction suppressed Ca2+ CRCs, similar to verapamil. In guinea‐pig ileum, Mn.Cr, its aqueous and ethyl acetate fractions exhibited atropine‐sensitive gut stimulant activity along with additional uncharacterized excitatory response in the aqueous fraction only. These results suggest that black mulberry possesses prokinetic, laxative, and antidiarrheal effects, putatively mediated through cholinomimetic, antimuscarinic, and Ca2+ antagonist mechanisms, respectively. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Human leukocyte antigen (HLA)-G acts as negative regulator of the immune responses and its expression in tumor cells may enable them to escape immunosurveillance. The purpose of this study was to investigate the influence of HLA-G polymorphism on risk of high-grade cervical intraepithelial neoplasia (HG-CIN) and cervical cancer in a Canadian population. The authors have analyzed 1,372 women from participants recruited between 2001 and 2009 in the ongoing Biomarkers of Cervical Cancer Risk case-control study. A total of 539 women with histologically confirmed HG-CIN and invasive cancer formed the case series, and 833 women with normal cytology served as controls. Cervical specimens were tested for human papillomavirus (HPV) DNA using the MY09/11 PCR protocol and HLA-G alleles where determined using a direct DNA sequencing procedures. HLA-G polymorphisms were not associated with HG-CIN or HPV infection. However, the risk for invasive cancer was significantly increased with the homozygous genotypes HLA-G*01:01:02 [odds ratio (OR) = 3.52, 95% confidence interval (CI): 1.43-8.61, p = 0.006], -G*01:06 (OR = 19.1, 95% CI: 2.29-159, p = 0.005) and -G* 3'UTR 14-bp insertion (OR = 2.17, 95% CI: 1.10-4.27, p = 0.020), whereas, the heterozygotic form of the G*01:01:01 wild-type allele was significantly associated with a reduced risk of invasive cancer (OR = 0.31, 95% CI: 0.16-0.59, p < 0.0001) after adjusting for age, HPV infection and ethnicity. These associations were also observed with progression of disease from HG-CIN to invasive cancer among HPV-positive women. These results suggest that HLA-G polymorphism is an independent risk factor for the development of invasive cervical cancer.  相似文献   
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Cervical cancer (CC) morbidity and mortality have decreased in the United States, but they remain high among black women. We assessed racial disparities in CC mortality, accounting for socioeconomic status (SES). We linked data from the 1988 to 2007 Surveillance Epidemiology and End Results (SEER) database to the US Census. Additional SES information was obtained through linkage with Area Resource Files. We used the Kaplan–Meier method for estimating probabilities following CC diagnosis and Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for CC mortality by race. The models were incrementally adjusted for marital status, registry, period, stage, age at diagnosis, histology, treatment, household income, poverty and unemployment rates. We stratified the analyses by disease stage and American state. A total of 44,554 women with CC were identified. Compared to white women, black women had a higher risk of dying from CC; crude and adjusted HRs were 1.41 (CI: 1.34–1.48) and 1.09 (CI: 1.03–1.15), respectively. Corresponding estimates for Hispanic women were 0.85 (CI: 0.80–0.89) and 0.75 (CI: 0.71–0.80). Black women diagnosed at late disease stages had a higher risk of CC death, whereas Hispanic women diagnosed at early and late stages had significantly lower risks. Black CC patients in California experienced poorer survival relative to white women. Conversely, longer CC survival was seen among Hispanic women in California, Georgia and Utah. While crude estimates indicated an increased CC death risk among black women, risks diminished upon adjustment for clinical and sociodemographic characteristics.  相似文献   
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