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排序方式: 共有894条查询结果,搜索用时 15 毫秒
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Christina Andreou Gregor Leicht Vlad Popescu Oliver Pogarell Paraskevi Mavrogiorgou Dan Rujescu Ina Giegling Michael Zaudig Georg Juckel Ulrich Hegerl Christoph Mulert 《Journal of psychiatric research》2013
Converging evidence suggests that frontostriatal abnormalities underlie OCD symptoms. The event-related potential P300 is generated along a widely distributed network involving several of the areas implicated in OCD. P300 abnormalities reported in patients with OCD suggest increased activity in these areas. The aim of the present study was to investigate this assumption in unmedicated patients with OCD, and to assess the effects of OCD treatment on P300 brain activity patterns. Seventy-one unmedicated patients with a DSM-IV diagnosis of OCD and 71 age- and gender-matched healthy control subjects participated in the study. The P300 was obtained through 32-channel EEG during an auditory oddball paradigm. Forty-three patients underwent a second EEG assessment after treatment with sertraline and behavioural therapy. Low-resolution electromagnetic tomography (LORETA) was used to localize the sources of brain electrical activity. Results: Increased P300-related activity was observed predominantly in the left orbitofrontal cortex, but also in left prefrontal, parietal and temporal areas, in patients compared to controls at baseline. After treatment, reduction of left middle frontal cortex hyperactivity was observed in patients. Conclusions: Findings of increased activity in frontoparietal areas in patients are consistent with several previous studies. Importantly, OCD treatment led to reduction of hyperactivity in the left middle frontal cortex, an area associated with context processing and uncertainty that might be important for the emergence of OCD symptoms. Thus, the present study is the first to show an association between P300 abnormalities and activity in brain regions postulated to be involved in the pathophysiology of OCD. 相似文献
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Zairis MN Papadaki OA Psarogianni PK Thoma MA Andrikopoulos GK Batika PC Poulopoulou CG Trifinopoulou KG Olympios CD Foussas SG 《American heart journal》2003,146(6):1082-1089
Background
Previous studies have shown an incremental role of inflammation in late prognosis following coronary stenting (CS). In particular, high preprocedural levels of plasma C-reactive protein (CRP) have been related to increased hazard of late ischemic complications. Persistent Chlamydia pneumoniae (Cp) infection, detected by positive IgA anti-Cp titers, may be associated with this inflammatory process and portend a high risk of late adverse prognosis after CS.Methods
A total of 483 consecutive patients with either stable or unstable coronary syndromes were followed-up for 1 year after successful CS. The composite of cardiac death, myocardial infarction, rehospitalization for rest-unstable angina, and exertional angina, whichever occurred first, was the clinical end point. Additionally, the rate of in-stent restenosis and progression of coronary artery disease during this period were evaluated. Anti-Cp titers and plasma CRP levels were measured before the procedure.Results
Positive immunoglobulin A (IgA), but not positive immunoglobulin G (IgG), titers were significantly associated with high plasma CRP levels in patients with unstable coronary syndromes (P = .005), but not in those with stable angina (P = .7). Moreover, positive IgA titers were significantly related to increased risk of both the composite clinical end point (P = .04) and progression of coronary artery disease (P < .001) in patients with unstable coronary syndromes but not in those with stable angina. Neither positive IgA nor positive IgG titers were associated with the rate of in-stent restenosis.Conclusions
Persistent Cp infection may drive an inflammatory response in the coronary vasculature and portends an adverse late outcome after CS in patients with unstable coronary syndromes. 相似文献36.
Konstantina Papalexopoulou Athanasios Chalkias Ioannis Dontas Paraskevi Pliatsika Charalampos Giannakakos Panagiotis Papapanagiotou Afroditi Aggelina Theodoros Moumouris Georgios Papadopoulos Theodoros Xanthos 《Heart & lung : the journal of critical care》2014
Objectives
To examine whether education and age affect skill acquisition and retention in lay rescuers after a European Resuscitation Council (ERC) CPR/AED course.Background
Because of the importance of bystander CPR/AED skills in the setting of cardiac arrest, acquisition and retention of resuscitation skills has gained a great amount of interest.Methods
The ERC CPR/AED course format for written and practical evaluation was used. Eighty lay people were trained and evaluated at the end of the course, as well as at one, three, and six months.Results
Retention of CPR/AED skills improved over time, recording the lowest practical scores at one month after initial training and the lowest written scores at initial training. In practical evaluation scores, when examined longitudinally, age presented a significant adverse effect and higher background education presented a non-significant positive effect. Moreover, regarding written evaluation scores, when examined longitudinally, education presented a significant positive effect while age did not significantly correlate with written scores.Conclusions
Education and age affected retention of CPR/AED skills in lay rescuers. Also, our results suggest that the ERC CPR/AED course format may be poorly designed to discriminate between participants with different levels of practical and written resuscitation skills and merit a thorough investigation in future studies. 相似文献37.
Lisa D.S. Bloomer Christopher P. Nelson Matthew Denniff Paraskevi Christofidou Radoslaw Debiec John Thompson Ewa Zukowska-Szczechowska Nilesh J. Samani Fadi J. Charchar Maciej Tomaszewski 《Atherosclerosis》2014
Objective
Amongst middle-aged men, haplogroup I is associated with ≈50% higher risk of coronary artery disease than other paternal lineages of Y chromosome. We hypothesised that carriers of haplogroup I had higher levels of aggression and estrogens and/or lower levels of androgens early in life and thus might be more prone to cardiovascular disease than men with other lineages of Y chromosome.Methods
We reconstructed phylogenetic tree of the Y chromosome in >1000 young apparently healthy white men from the general population. Each Y chromosome was classified into one of 13 most common European lineages. Androgens (DHEA-S, androstenedione, total testosterone) and their metabolites (total estradiol, estrone) were measured by radioimmunoassays. Information on five dimensions of aggression (total, physical, verbal, anger and hostility) was collected using Buss and Perry questionnaire.Results
Approximately 17% men inherited haplogroup I from their fathers. Carriers of haplogroup I showed lower scores of verbal aggression than men with other haplogroups (β = −0.72, SE = 0.29, P = 0.012) and when further compared to carriers of most common R1a lineage and other haplogroups (β = −1.03, SE = 0.34, P = 0.003). However, these associations did not survive a correction for multiple testing. Sex steroids did not show even nominal level of association with haplogroup I.Conclusion
Our data show no overall association between haplogroup I and sex-related phenotypes in young white men. These results also suggest that the previously identified association between haplogroup I and coronary artery disease is not likely mediated by unfavourable profile of sex steroids or heightened aggression early in life. 相似文献38.
Canan Ulusoy Eunmi Kim Erdem Tüzün Ruksana Huda Vuslat Yılmaz Konstantinos Poulas Nikos Trakas Lamprini Skriapa Athanasios Niarchos Richard T. Strait Fred D. Finkelman Selin Turan Paraskevi Zisimopoulou Socrates Tzartos Güher Saruhan-Direskeneli Premkumar Christadoss 《Clinical immunology (Orlando, Fla.)》2014,151(2):155-163
Myasthenia gravis (MG) is an autoimmune disease characterized by muscle weakness associated with acetylcholine receptor (AChR), muscle-specific receptor kinase (MuSK) or low-density lipoprotein receptor-related protein 4 (LRP4)-antibodies. MuSK-antibodies are predominantly of the non-complement fixing IgG4 isotype. The MuSK associated experimental autoimmune myasthenia gravis (EAMG) model was established in mice to investigate immunoglobulin (Ig) and cytokine responses related with MuSK immunity. C57BL/6 (B6) mice immunized with 30 μg of recombinant human MuSK in incomplete or complete Freund's adjuvant (CFA) showed significant EAMG susceptibility (> 80% incidence). Although mice immunized with 10 μg of MuSK had lower EAMG incidence (14.3%), serum MuSK-antibody levels were comparable to mice immunized with 30 μg MuSK. While MuSK immunization stimulated production of all antibody isotypes, non-complement fixing IgG1 was the dominant anti-MuSK Ig isotype in both sera and neuromuscular junctions. Moreover, MuSK immunized IgG1 knockout mice showed very low serum MuSK-antibody levels. Sera and MuSK-stimulated lymph node cell supernatants of MuSK immunized mice showed significantly higher levels of IL-4 and IL-10 (but not IFN-γ and IL-12), than those of CFA immunized mice. Our results suggest that through activation of Th2-type cells, anti-MuSK immunity promotes production of IL-4, which in turn activates anti-MuSK IgG1, the mouse analog of human IgG4. These findings might provide clues for the pathogenesis of other IgG4-related diseases as well as development of disease specific treatment methods (e.g. specific IgG4 inhibitors) for MuSK-related MG. 相似文献
39.
Erhan Akinci Max-Oskar Wieser Simon Vanscheidt Shirin Diop Vera Flasbeck Burhan Akinci Cora Stiller Georg Juckel Paraskevi Mavrogiorgou 《Psychiatry investigation》2022,19(3):178
ObjectiveDespite the numerous findings on the altered emotion recognition and dysfunctional social interaction behavior of depressive patients, a lot of the relationships are not clearly clarified.MethodsIn this pilot study, 20 depressive patients (mean±SD, 38.4±14.2) and 20 healthy subjects (mean±SD, 38.9±15.3) (each in dyads) were videographed. We then analyzed their social interaction behavior and emotion processing in terms of emotion recognition, their own emotional experience, and the expression of emotions under the conditions of a semi-structured experimental paradigm. ResultsPatients showed more significant impairment regarding the dimensions of social interaction behavior (i.e., attention, interest, and activity) and their interaction behavior was characterized by neutral affectivity, silence, and avoidance of direct eye contact. This interactive behavioral style was statistically related to depressive psychopathology. There were no differences concerning emotion recognition. ConclusionImpairments of non-verbal and verbal social interaction behavior of depressive patients seem to be less associated with disturbances of basic skills of emotion recognition. 相似文献
40.
Mylona E Alexandrou P Giannopoulou I Liapis G Sofia M Keramopoulos A Nakopoulou L 《Gynecologic oncology》2007,104(3):557-563
OBJECTIVES: Vascular endothelial growth factors A and B (VEGF-A and VEGF-B) play a major role in angiogenesis and activate VEGF receptor 1 (VEGFR-1). However, the clinicopathologic and clinical value of VEGF-B and VEGFR-1 in invasive breast carcinoma remains unclear. METHODS: We immunohistochemically examined the expression pattern of VEGF-A, VEGF-B and VEGFR-1 in 177 invasive breast carcinomas in relation to clinicopathological parameters, p53, c-erbB2 proteins expression and patients' survival. RESULTS: VEGF-A, VEGF-B and VEGFR-1 were immunodetected predominantly in the cytoplasm of the malignant cells. None of the studied markers correlated with any of the clinicopathological parameters, other than stromal VEGFR-1 which inversely correlated with PR (p=0.021). Cancerous VEGF-A and stromal VEGFR-1 were positively related to p53 (p=0.016 and p=0.033, respectively). Cancerous VEGF-B was positively associated with c-erbB-2 (p=0.045) and was found to exert an unfavorable impact on both disease-free and the overall survival of the node-positive patients (p=0.05 and p=0.029, respectively). Cancerous VEGFR-1 was recognized as being an independent poor prognostic indicator (p=0.037). CONCLUSION: These findings suggest that, while VEGF-B seems to be useful as a prognostic indicator only in node-positive patients, VEGFR-1 may be an independent poor prognosticator in patients with invasive breast carcinoma. 相似文献