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Objectives: The aim of this study was to longitudinally evaluate the epidemiological characteristics of headaches in a school‐based, community setting and to determine the impact of headache symptoms on the health of children. Methods: After institutional review board approval, a prospective cohort study was conducted at two Chicago public schools for a period of 6 months. Members of the research team surveyed both schools weekly for headache and other pain symptoms. The students rated each pain symptom on a 5‐point scale from 0 (“not at all”) to 4 (“a whole lot”). Demographic information was collected at the time of enrollment, and all participants were asked to complete age‐appropriate and validated pediatric surveys to assess the severity of concurrent somatic complaints, anxiety symptoms, functional limitations, and quality of life issues. Results: Of the participating children, 89.5% reported at least one headache during the study period. Females experienced more frequent headaches compared with males (P < 0.05). Children reporting headaches had a significantly increased risk of experiencing other troubling somatic symptoms (P < 0.05). Headache severity showed a moderate correlation with increased feelings of anxiety, functional disability, and a diminished quality of life (P < 0.05). Conclusions: School‐aged children commonly experience headaches. Children experiencing headaches are more likely to report other somatic symptoms, feelings of anxiety, functional limitations, and quality of life impairments.  相似文献   
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Essential hypertension is a proinflammatory, proconstrictor disease coinciding with endothelial dysfunction and inward vessel remodeling. Using the skin circulation, our aim was to determine whether inducible NO synthase (iNOS) upregulation attenuates NO-dependent cutaneous vasodilation in hypertensive humans. We hypothesized that, with hypertension, localized iNOS inhibition would restore vasodilation in response to NO-dependent stimuli, and iNOS expression would be increased and phosphorylated vasodilator-stimulated phosphoprotein would be decreased. For, in vivo protocols, 4 intradermal microdialysis fibers were placed in 9 hypertensive and 10 normotensive men and women (systolic blood pressure: 146±4 versus 113±2 mm Hg; P<0.001). Microdialysis fibers served as control, iNOS inhibited (1400 W), neuronal NO synthase inhibited (N(ω)-propyl-l-arginine), and nonselective NOS inhibited (N(G)-nitro-l-arginine methyl ester). Cutaneous vascular conductance was calculated (percentage of sodium nitroprusside) during standardized local heating (42°C) and acetylcholine dose-response protocols (0.01, 0.10, 1.00, 5.00, 10.00, 50.00, 100.00 mmol/L). The NO-dependent local heating response was attenuated at control (95±2% versus 76±2% cutaneous vascular conductance; P<0.05) and neuronal NO synthase-inhibited sites (94±4% versus 77±3% cutaneous vascular conductance; P<0.01) in hypertensives. iNOS inhibition augmented the NO-dependent local heating response (93±2% versus 89±10% cutaneous vascular conductance). Acetylcholine-induced vasodilation was attenuated in control sites at doses ≥0.1 mmol/L of acetylcholine in hypertensives and was restored with iNOS inhibition (0.1 mmol/L, P<0.05; 1, 5, and 10 mmol/L, P<0.001; 50 and 100 mmol/L, P<0.01). In vitro iNOS expression was increased (P=0.006) and phosphorylated vasodilator-stimulated phosphoprotein was decreased in skin from hypertensive humans (P=0.04). These data suggest that iNOS is upregulated in essential hypertensive humans and contributes to reduced NO-dependent cutaneous vasodilation.  相似文献   
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Prostacyclin (PGI(2)) is a potent vasodilator that exerts multiple vasoprotective effects in the cardiovascular system. The effects of PGI(2) are mediated by activation of the cell membrane G-protein-coupled PGI(2) receptor (IP receptor). More recently, however, it has been suggested that PGI(2) might also serve as an endogenous ligand and activator of nuclear peroxisome proliferator-activated receptorδ (PPARδ). Consistent with this concept, studies designed to define pharmacological properties of stable PGI(2) analogs revealed that beneficial effects of these compounds appear to be mediated, in part, by activation of PPARδ. This review discusses emerging evidence regarding the contribution of PPARδ activation to vasoprotective and regenerative functions of PGI(2) and stable analogs of PGI(2).  相似文献   
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Prenatal cocaine exposure (PCE) is associated with attention/arousal dysregulation and possible inefficiencies in some cognitive functions. However, the neurobiological bases of these teratogenic effects have not been well characterized. Because activities in the default mode network (DMN) reflect intrinsic brain functions that are closely associated with arousal regulation and cognition, alterations in the DMN could underlie cognitive effects related to PCE. With resting‐state and task activation functional magnetic resonance imaging (fMRI), this study investigated the possible PCE related changes in functional brain connectivity and brain activation in the DMN. In the resting state, the PCE group was found to have stronger functional connectivity in the DMN, as compared to the nonexposed controls. During a working memory task with emotional distracters, the PCE group exhibited less deactivation in the DMN and their fMRI signal was more increased by emotional arousal. These data revealed additional neural effects related to PCE, and consistent with previous findings, indicate that PCE may affect behavior and functioning by increasing baseline arousal and altering the excitatory/inhibitory balancing mechanisms involved in cognitive resource allocation. Hum Brain Mapp, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
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The American Society of Regional Anesthesia and Pain Medicine (ASRA) Practice Advisory on Neurologic Complications in Regional Anesthesia and Pain Medicine includes an evidence- and expert opinion-based section on performing procedures on anesthetized or heavily sedated patients. This practice advisory is based on existing scientific literature, pathophysiological principles, and expert opinion. The advisory panel examined the ability of anesthetized or heavily sedated patients to recognize and report intravascular injection of local anesthetic or impending neurologic injury. The advisory panel also considered whether or not the ability to recognize and report symptoms could actually affect the occurrence of nerve injury or local anesthetic systemic toxicity. The advisory contains recommendations pertaining to both adult and pediatric patients.  相似文献   
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