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排序方式: 共有2179条查询结果,搜索用时 478 毫秒
41.
ABSTRACT: BACKGROUND: Various medications of natural origin have effectively treated stress-related disorders, such as sleep disturbances and agitated conditions. The efficacy of Neurexan, a multicomponent, low-dose medication, has been demonstrated in observational studies, but its exact mechanism of action has not been determined. METHODS: To characterize the effects of Neurexan on the central nervous system, we analyzed the spectral frequencies of field potentials in four rat brain areas after a single oral administration of Neurexan. Different doses of Neurexan were tested within a crossover design, and effects were compared with vehicle control. RESULTS: Significant effects were observed with 0.5 tablets of Neurexan, predominantly on delta- and theta-waves in the frontal cortex and reticular formation (P < 0.01). In the reticular formation, significant changes of delta- and theta-waves occurred as early as during the first hour after administration. The time course revealed a significant and longer-lasting increase of delta- and theta-waves in the frontal cortex and reticular formation, whereas other spectral frequencies were only transiently affected in the frontal cortex, reticular formation, and striatum. CONCLUSION: In conclusion, this study demonstrated that the low-dose medication Neurexan influences central nervous system activity in rats. The resulting electroencephalographic profile of Neurexan shows several similarities with those of other calming agents, such as Valeriana and Passiflora, suggesting a potential benefit of Neurexan for patients with stress-related disorders. Moreover, this report demonstrates that electroencephalographic signatures are also valid biomarkers for the assessment of low-dose medications, such as Neurexan. 相似文献
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Wilfried Scharmüller Verena Leutgeb Florian Sch?nga?ner Andrea Hermann Rudolf Stark Anne Schienle 《Social cognitive and affective neuroscience》2014,9(10):1584-1588
Recent symptom provocation studies that compared patients suffering from dental phobia with healthy controls identified hyperactivation of basal ganglia structures, but none have assessed striatal functional connectivity. We reanalyzed data from a previous functional magnetic resonance imaging study on dental phobia. Patients (20 men, 25 women) and healthy controls (18 men, 23 women) had been exposed to pictures showing dental treatment, and neutral contents. We conducted connectivity analyses via psychophysiological interactions (PPIs). Relative to non-phobic controls, the patients showed decreased connectivity between prefrontal and basal ganglia regions. Moreover, the clinical group was characterized by increased internal basal ganglia connectivity, which was more pronounced in female compared with male patients. This study provides first evidence for an altered information flow within a fronto-striatal network in dentophobic individuals during visual symptom provocation, which can be considered a neuromarker of this disorder. 相似文献
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Christa Meisinger Hannelore Loewel Wilfried Mraz Wolfgang Koenig 《European heart journal》2005,26(3):271-278
AIMS: To investigate the association between apolipoprotein B (apoB), A-I (apoA-I), the apoB/apoA-I ratio, and the incidence of coronary events. METHODS AND RESULTS: Analysis included 1414 men and 1436 women aged 35-64 years without a prior coronary event who participated in the population-based MONICA Augsburg survey 1984-85 (median followed-up period 13 years). Incidence of fatal and non-fatal myocardial infarction, and sudden cardiac death was assessed using data of the MONICA/KORA Augsburg coronary event registry. During follow-up, 114 incident coronary events occurred in men and 31 in women. In multivariable analysis, an increase of 1 standard deviation in the serum concentration of apoB was associated with an increased risk of coronary events in men [hazard ratio (HR)=1.49; 95% confidence interval (CI); 1.25-1.78] and in women (HR=1.73; 95% CI; 1.32-2.27). By contrast, elevated concentrations of apoA-I were not associated with a significantly decreased risk of coronary events in either sex (HR=0.91). Furthermore, the predictive power of the apoB/apoA-I ratio was similar to that of the total cholesterol/HDL cholesterol ratio in men and women. CONCLUSION: ApoB and the apoB/apoA-I ratio were strong predictors of coronary events in middle-aged men and women, whereas apoA-I did not add significantly to the estimation of future coronary risk. 相似文献
46.
A functional single-nucleotide polymorphism of the G-CSF receptor gene predisposes individuals to high-risk myelodysplastic syndrome 总被引:2,自引:0,他引:2
Wölfler A Erkeland SJ Bodner C Valkhof M Renner W Leitner C Olipitz W Pfeilstöcker M Tinchon C Emberger W Linkesch W Touw IP Sill H 《Blood》2005,105(9):3731-3736
The granulocyte colony-stimulating factor receptor (G-CSF-R) transmits signals for proliferation and differentiation of myeloid progenitor cells. Here we report on the identification of a rare single nucleotide polymorphism within its intracellular domain (G-CSF-R_Glu785Lys). Screening a cohort of 116 patients with primary myelodysplastic syndromes (MDS), de novo acute myeloid leukemia (AML) (84 patients), as well as 232 age- and sex-matched controls revealed a highly significant association of the G-CSF-R_785Lys allele with the development of high-risk MDS as defined by more than 5% bone marrow blasts (9.7% versus 0.9% in controls; P = .001; odds ratio [OR], 12.5; 95% confidence interval [CI], 2.4-58.9) or an International Prognostic Scoring System score of intermediate-2 or high (13.0% versus 0.9%; P < .001; OR, 14.0; 95% CI, 3.4-85.0). Functional analysis by retroviral transfer of G-CSF-R_785Lys into myeloid progenitor cells of G-CSF-R-deficient mice showed a significantly diminished colony-formation capacity after G-CSF stimulation as compared with cells transduced with the wild-type receptor. These results suggest that lifelong altered G-CSF response by the G-CSF-R_785Lys may render individuals susceptible to development of high-risk MDS. 相似文献
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Gagnaire Béatrice Bado-Nilles Anne Betoulle Stéphane Amara Rachid Camilleri Virginie Cavalié Isabelle Chadili Edith Delahaut Laurence Kerambrun Elodie Orjollet Daniel Palluel Olivier Sanchez Wilfried 《Ecotoxicology (London, England)》2015,24(1):215-231
Ecotoxicology - To characterize environmental risks linked to former uranium mines in the Limousin region of France, a study was conducted on fish health effects from uranium releases. Two private... 相似文献
49.
Elevated intra-abdominal pressure in acute decompensated heart failure: a potential contributor to worsening renal function? 总被引:1,自引:0,他引:1
Wilfried Mullens Zuheir Abrahams Hadi N Skouri Gary S Francis David O Taylor Randall C Starling Emil Paganini W H Wilson Tang 《Journal of the American College of Cardiology》2008,51(3):300-306
OBJECTIVES: This study sought to determine whether changes in intra-abdominal pressure (IAP) with aggressive diuretic or vasodilator therapy are associated with improvement in renal function in acute decompensated heart failure (ADHF). BACKGROUND: Elevated IAP (>or=8 mm Hg) is associated with intra-abdominal organ dysfunction. There is potential for ascites and visceral edema causing elevated IAP in patients with ADHF. METHODS: Forty consecutive patients admitted to a specialized heart failure intensive care unit for management of ADHF with intensive medical therapy were studied. The IAP was measured using a simple transvesical technique at time of admission and before removal of the pulmonary artery catheter. RESULTS: In our study cohort (mean age 59 +/- 13 years, mean left ventricular ejection fraction 19 +/- 9%, baseline serum creatinine 2.0 +/- 0.9 mg/dl), the mean baseline IAP was 8 +/- 4 mm Hg, with 24 (60%) patients having elevated IAP. Elevated IAP was associated with worse renal function (p = 0.009). Intensive medical therapy resulted in improvement in both hemodynamic measurements and IAP. A strong correlation (r = 0.77, p < 0.001) was observed between reduction in IAP and improved renal function in patients with baseline elevated IAP. However, changes in IAP or renal function did not correlate with changes in any hemodynamic variable. CONCLUSIONS: Elevated IAP is prevalent in patients with ADHF and is associated with impaired renal function. In the setting of intensive medical therapy for ADHF, changes in IAP were better correlated with changes in renal function than any hemodynamic variable. 相似文献
50.
Beer M Seyfarth T Sandstede J Landschütz W Lipke C Köstler H von Kienlin M Harre K Hahn D Neubauer S 《Journal of the American College of Cardiology》2002,40(7):1267-1274
OBJECTIVE: The purpose of the present study was to measure absolute concentrations of phosphocreatine (PCr) and adenosine triphosphate (ATP) in normal, hypertrophied, and failing human heart. BACKGROUND: Conflicting evidence exists on the extent of changes of high-energy phosphate metabolites in hypertrophied and failing human heart. Previous reports using phosphorus-31 magnetic resonance spectroscopy ((31)P-MRS) have quantified metabolites in relative terms only. However, this analysis cannot detect simultaneous reductions. METHODS: Four groups of subjects (n = 10 each), were studied: volunteers and patients with hypertensive heart disease (HHD), aortic stenosis, and dilated cardiomyopathy (DCM). Left ventricular (LV) function and mass were measured by cine magnetic resonance imaging. Absolute and relative concentrations of PCr and ATP were determined by (31)P-MRS with spatial localization with optimum point spread function. RESULTS: Left ventricular ejection fraction remained normal in HHD and aortic stenosis, but was severely reduced to 18% in DCM; LV mass was increased by 55%, 79%, and 68% respectively. In volunteers, PCr and ATP concentrations were 8.82 +/- 1.30 mmol/kg wet weight and 5.69 +/- 1.02 mmol/kg wet weight, and the PCr/ATP ratio was 1.59 +/- 0.33. High-energy phosphate levels were unaltered in HHD. In aortic stenosis, PCr was decreased by 28%, whereas ATP remained constant. In DCM, PCr was reduced by 51%, ATP by 35%, and reduction of the PCr/ATP ratio by 25% was of borderline significance (p = 0.06). Significant correlations were observed among energetic and functional variables, with the closest relations for PCr. CONCLUSIONS: In human heart failure due to DCM, both PCr and ATP are significantly reduced. Ratios of PCr to ATP underestimate changes of high-energy phosphate levels. 相似文献