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41.
Early life stress (ELS) is known to have considerable influence on brain development and affective functioning. Previous studies in clinical populations have shown that hippocampus and amygdala, two central structures of limbic emotion processing circuits, are predominantly affected by early stress exposure. Given the inconsistent findings on ELS‐related effects in healthy populations and the associations of ELS and affective functioning, the question arises which additional emotion‐relevant variables need to be considered to better understand the effects of ELS. We, therefore, investigated the volume of hippocampus and amygdala in 25 high alexithymic (h‐ALEX) and 25 low alexithymic (l‐ALEX) individuals, which were matched with regard to ELS, but significantly differed in their degree of emotional functioning. Volumetric analyses were performed using FSL‐FIRST, a method to automatically segment subcortical structures on T1‐weighted magnetic resonance images. Alexithymia was assessed using the Toronto Alexithymia Scale and Bermond–Vorst Alexithymia Questionnaire. ELS was assessed by Childhood Trauma Questionnaire (CTQ) and Early Trauma Inventory. Our data showed that ELS was negatively associated with right hippocampus volume in h‐ALEX individuals, while there was no such association in the l‐ALEX group. Furthermore, ELS was positively associated with left amygdala volume in l‐ALEX individuals, but not in individuals with high levels of alexithymia. The present study emphasizes a substantial relationship between intrapersonal factors, such as alexithymia and neural alterations related to the experience of ELS. Longitudinal study designs are necessary to pursue the question of how emotional abilities interact with individual adaptations to early stress exposure on the neural level. © 2014 Wiley Periodicals, Inc.  相似文献   
42.
Growth-associated protein (GAP)-43 is a neuron-specific phosphoprotein whose expression is associated with axonal outgrowth during neuronal development and regeneration. In order to investigate the expression of this gene product in the early developing nervous system we have isolated and sequenced a cDNA for chicken GAP-43. The predicted amino acid sequence for chicken GAP-43 displays extensive similarity to that of the mammalian protein, particularly in the amino-terminal region, to which functional domains of the protein have been assigned. The cDNA hybridizes with two RNAs of differing molecular weights on Northern blots; both appear to be regulated similarly. These RNAs first appear in the brain on embryonic day 3 (E3), suggesting that GAP-43 begins to be expressed when neuroblasts become post-mitotic. In situ hybridization analysis reveals that GAP-43 RNA is expressed by several neural structures in the chick embryo, including derivatives of the neural tube, neural crest, and neuroectodermal placodes.  相似文献   
43.
Acute iron intoxication is associated with depletion of reduced glutathione in hepatocytes and changes in the glutathione system enzymes. We hypothesized that treatment with N-acetylcysteine (NAC), a glutathione reducing agent and an antioxidant, would reduce mortality in acute iron intoxication. We used a rat model to test this hypothesis. Male rats were assigned to 4 groups. Group 1 received 400 mg/kg elemental iron by oral gavage, group 2 received the same dose of iron followed by NAC, group 3 received NAC only, whereas group 4 received distilled water. Iron and liver transaminases in the blood, and glutathione system enzymes in the liver and erythrocytes were measured. Mortality in group 2 was significantly higher after 2, 6, and 24 hours compared with group 1 (P < .001). No deaths were observed in groups 3 and 4. Serum iron levels were significantly higher in group 2 rats compared to group 1 rats (P < .001). Hepatic and erythrocyte glutathione system enzymes were significantly lower among rats in group 2 compared to rats in group 1. The administration of NAC probably increased the absorption of iron through the gastrointestinal tract, causing higher serum iron levels with significant hepatic damage. These results indicate that in a rat model of acute iron intoxication, orally administered NAC may increase mortality.  相似文献   
44.
Aim: To investigate the effect of anaesthetic agents on transcutaneous bilirubin levels during the first 24 h in neonates delivered by caesarean section. Methods: A total of 168 neonates delivered by caesarean section, during which sevoflurane was used for general anaesthesia (group A), bupivacaine for spinal anaesthesia (group B), levobupivacaine for epidural anaesthesia (group C) and 155 neonates delivered vaginally were included in the study. Transcutaneous bilirubin levels (TBLs) of infants were measured during the first 24 h and compared with each other. Results: The TBLs in neonates delivered vaginally were higher than those delivered by caesarean section, but the difference was not significant. TBLs were higher in groups A and C than in group B (p = 0.034, p = 0.011 respectively). TBLs were higher in group C than in group A, but the difference was not significant (p > 0.05). When the groups were compared with vaginal delivery group, TBLs in groups A and C were found higher (p = 0.03, p = 0.022 respectively). Conclusion: The route of delivery had no effect on TBL. While bupivacaine was found to have no effect on neonatal bilirubin levels, levobupivacaine increased neonatal biluribin levels, but further studies are needed for definite results.  相似文献   
45.
Sulcus vocalis is the presence of a groove extending along the vibratory surface of a vocal fold and may result in dysphonia. Depending on the level of severity, this condition may require treatment involving complicated surgical techniques. Cases of sulcus vocalis are classified as physiological, vergeture, or pouch type. A clear explanation of the etiology has not been established, and the currently proposed congenital origin, as described in the literature, remains controversial. This paper presents findings from monozygotic twin sisters with bilateral sulcus vocalis; these patients had similar morphologies, vibratory characteristics, and vocal quality measurements, which support the theory of a congenital etiology.  相似文献   
46.
47.
STUDY OBJECTIVE: To compare hemodynamics, recovery profiles, early postoperative pain control and costs of total intravenous anesthesia (TIVA) with propofol and remifentanil and propofol and alfentanil. DESIGN: Randomized, double-blind study. SETTING: University hospital. PATIENTS: 40 ASA physical status I and II adult patients scheduled for lumbar discectomy. INTERVENTIONS: Patients were randomly assigned to receive either remifentanil-propofol or alfentanil-propofol. Anesthesia was induced with remifentanil 1 microg kg(-1) or alfentanil 20 microg kg(-1) with propofol 2 mg kg(-1), and maintained with infusions of propofol 150 to 100 microg kg(-1)min(-1) and either remifentanil 0.1 microg kg(-1) min(-1) or alfentanil 0.5 microg kg(-1) min(-1). MEASUREMENTS: Hemodynamic parameters (heart rate and mean arterial pressure), times to awakening, and tracheal extubation were recorded. In the postanesthesia care unit, pain level, frequency of analgesic demand, frequency of postoperative nausea and vomiting (PONV), partial oxygen saturation (SpO2), and respiratory rates were noted. Drug dosages and costs of each technique were determined. MAIN RESULTS: The mean arterial pressure significantly decreased compared to baseline values 1 minute after induction (p < 0.05) in both groups, and it significantly decreased at 5, 15, and 30 minutes perioperatively in the remifentanil group compared to the alfentanil group (p < 0.05). Time of extubation, spontaneous eye opening, and response to verbal command were similar in both groups. Visual analog scale pain scores at 30 minutes and 60 minutes were significantly lower in the alfentanil group than remifentanil group (p < 0.05). At 15, 30, and 60 minutes after terminating the operation oxygen saturation and respiratory rate were significantly higher (p < 0.05) and analgesics were required sooner in the remifentanil group than the alfentanil group (p < 0.05). The frequency of PONV was similar in both groups. The remifentanil-propofol anesthesia was found to be slightly more expensive as compared to the alfentanil based TIVA (33.41 +/- 4.53 vs. 29.97 +/- 4.1 USD) (p < 0.05). CONCLUSIONS: Both remifentanil and alfentanil provided a reasonably rapid and reliable recovery. The remifentanil-based TIVA was associated with high intraoperative cost and early postoperative pain, but it allowed a more rapid respiratory recovery.  相似文献   
48.
Glutaric aciduria type I is an uncommon inborn error of metabolism. It is a serious disease, often with a fatal outcome. Magnetic resonance imaging findings and the clinical course of monozygotic twin females with glutaric aciduria type I who were admitted with acute encephalopathic crisis symptoms 3 days after immunization for poliovirus are presented in this report. Magnetic resonance imaging findings revealed hyperintensity in the putamen, head of the left caudate nucleus, and globus pallidus, periventricular white matter (on T2-weighted images), arachnoid cysts in bilateral temporal regions, and enlargement of the sylvian fissures. Glutaric aciduria type I should be included in the differential diagnosis of patients with acute encephalopathic crisis occurring shortly after poliovirus immunization. Typical magnetic resonance findings guide urinary organic acid analysis in these patients.  相似文献   
49.
Mature spinal teratoma associated with thickened filum terminale   总被引:1,自引:0,他引:1  
A 30-year-old man presented with an intradural spinal teratoma with thickened filum terminale manifesting as urinary and sexual disturbances, and low back pain persisting for 4 years. Spinal magnetic resonance imaging revealed thickened filum terminale containing a heterogeneously enhanced intradural lesion extending from the L-3 to L-4 levels and in contact with the conus medullaris. The filum terminale was incised and the tumor was totally resected. The histological diagnosis was mature teratoma consisting of three germ cell layers. The patient's complaints had completely resolved 6 months later.  相似文献   
50.
There is increasing awareness of the importance of international health and medicine (IHM) but there is a paucity of data regarding medical students' attitudes towards and knowledge of the subject. To the best of our knowledge there is currently no validated measure to assess this. The aim of the present study was to develop a validated measure of medical students' attitudes and knowledge of IHM and examine its correlates. A panel experienced in IHM formulated attitude and general knowledge items and clinical cases based on personal experience, literature review and texts. The survey was piloted and then administered to 82 students of the Ben Gurion University-Columbia University MD program in IHM, and 59 students from programs without specific IHM focus. Cronbach's a was 0.87. Test-retest reliability of attitudes was r=0.87. Correlation of openness to experience with attitudes was r=0.376, showing construct validity. Third-year IHM students scored higher than incoming students on IHM knowledge and clinical cases, demonstrating sensitivity. General IHM knowledge was positively correlated to clinical IHM knowledge r=0.36, but not attitude or openness to experience. Those with previous IHM work experience showed greater openness and positive attitude. Women showed more positive attitudes towards IHM than men. Attitude was negatively correlated with number of languages spoken r=-0.198. The survey may be a reliable and valid tool to assess and compare medical students' knowledge and attitude toward international health. This survey can be used to evaluate curricular innovations in the field.  相似文献   
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