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81.
82.
Fyenbo Daniel Benjamin Sommer Anders Stephansen Charlotte Nørgaard Bjarne Linde Kronborg Mads Brix Kristensen Jens Gerdes Christian Jensen Henrik Kjærulf Jensen Jesper Møller Nielsen Jens Cosedis 《Journal of interventional cardiac electrophysiology》2022,64(3):783-792
Journal of Interventional Cardiac Electrophysiology - To evaluate the association between different right ventricular (RV) lead positions as assessed by cardiac computed tomography (CT) and... 相似文献
83.
Overall 1,021 patients with endometrial carcinoma were treated between 1965 and 1982 at the Department of Obstetrics and Gynecology and the Department of Radiology, Friedrich-Schiller-University, Jena. The 5-year-survival rate of all patients amounted to 63%. The 5-year-survival probability with primary surgery was 76.1%, with primary irradiation 34.4%. The frequency of risk factors in the patient group was compared with an age adjusted group of patients who underwent a D & C due to irregular bleeding of benign causes. Overweight and infertility were evaluated as significantly more frequent risk factors in cancer patients. There was no significant difference between the two groups concerning the factors hypertension, diabetes, heart-diseases, irregular bleeding and history of carcinoma in the family. 相似文献
84.
Arya A Piorkowski C Sommer P Bollmann A Hindricks G 《Herzschrittmachertherapie & Elektrophysiologie》2008,19(2):68-72
Atrial fibrillation (AF) is a common arrhythmia, affecting an estimated 2 million people in the United States and its prevalence increases with age, reaching 10% in those > or = 80 years. AF confers a four- to fivefold increased risk of stroke compared to the general population and has been associated with a doubling of all-cause mortality. During the past decade, limited success rates of drug treatment stimulated an exploration of interventional treatment options for AF. As our knowledge on initiating triggers and perpetuating substrate of AF expanded, different potentially curative catheter ablation techniques have been developed. In this article we review the current patient selection criteria, methods, and the results of the catheter ablation of atrial fibrillation. 相似文献
85.
The use of Doppler echocardiography is a routine part of the noninvasive assessment of the patient with heart disease. In children with congenital heart disease, pulsed- and continuous-wave Doppler echocardiographic techniques provide accurate, reproducible hemodynamic data relative to structural defects. Doppler color flow imaging, however, allows for qualitative assessment of blood flow patterns, which may give important insights into the changing physiology of the newborn infant or that of a patient in the medical or surgical intensive care settings. Ten cases are presented in which this flow information is instructive in understanding the physiological sequelae of congenital heart disease. 相似文献
86.
Georgiana M. Klug‐Micu Steffen Stenger Andrea Sommer Philip T. Liu Stephan R. Krutzik Robert L. Modlin Mario Fabri 《Immunology》2013,139(1):121-128
The ability of T cells to activate antimicrobial pathways in infected macrophages is essential to host defence against many intracellular pathogens. Here, we compared the ability of two T‐cell‐mediated mechanisms to trigger antimicrobial responses against Mycobacterium tuberculosis in humans, CD40 activation and the release of interferon‐γ (IFN‐γ). Given that IFN‐γ activates a vitamin D‐dependent antimicrobial response, we focused on induction of the key components of this pathway. We show that activation of human monocytes via CD40 ligand (CD40L) and IFN‐γ, alone, and in combination, induces the CYP27b1‐hydroxylase, responsible for the conversion of 25‐hydroxyvitamin D (25D) to the bioactive 1,25‐dihydroxyvitamin D (1,25D), and the vitamin D receptor (VDR). The activation of the vitamin D pathway by CD40L and IFN‐γ results in up‐regulated expression of the antimicrobial peptides, cathelicidin and DEFB4, as well as induction of autophagy. Finally, activation of monocytes via CD40L and IFN‐γ results in an antimicrobial activity against intracellular M. tuberculosis. Our data suggest that at least two parallel T‐cell‐mediated mechanisms, CD40L and IFN‐γ, activate the vitamin D‐dependent antimicrobial pathway and trigger antimicrobial activity against intracellular M. tuberculosis, thereby contributing to human host defence against intracellular infection. 相似文献
87.
Birgit Stürmer Guang Ouyang Changsong Zhou Annika Boldt Werner Sommer 《Psychophysiology》2013,50(1):70-73
When the lateralized readiness potential (LRP) is recorded in stimulus–response compatibility (SRC) tasks, two processes may overlap in the LRP, stimulus‐driven response priming and activation based on response selection rules. These overlapping processes are hard to disentangle with standard analytical tools. Here, we show that Residue Iteration Decomposition (RIDE), based on latency variability, separates the overlapping LRP components from a Simon task into stimulus‐driven and response‐related components. SRC affected LRP amplitudes only in the stimulus‐driven component, whereas LRP onsets were affected only in the response‐locked component. Importantly, the compatibility effect in reaction times was more similar to the effect in the onsets of the RIDE‐derived response‐locked LRP component than in the unseparated LRP. Thus, RIDE‐separated LRP components are devoid of distortions inherent to standard LRPs. 相似文献
88.
The disappointing results in bench-to-bedside translation of neuroprotective strategies caused a certain shift in stroke research towards enhancing the endogenous recovery potential of the brain. One reason for this focus on recovery is the much wider time window for therapeutic interventions which is open for at least several months. Since recently two large clinical studies using d-amphetamine or fluoxetine, respectively, to enhance post-stroke neurological outcome failed again it is a good time for a critical reflection on principles and requirements for stroke recovery science. In principal, stroke recovery science deals with all events from the molecular up to the functional and behavioral level occurring after brain ischemia eventually ending up with any measurable improvement of various clinical parameters. A detailed knowledge of the spontaneously occurring post-ischemic regeneration processes is the indispensable prerequisite for any therapeutic approaches aiming to modify these responses to enhance post-stroke recovery. This review will briefly illuminate the molecular mechanisms of post-ischemic regeneration and the principle possibilities to foster post-stroke recovery. In this context, recent translational approaches are analyzed. Finally, the principal and specific requirements and pitfalls in stroke recovery research as well as potential explanations for translational failures will be discussed. 相似文献
89.
Lili Sahakyan Tina Meller Ulrika Evermann Simon Schmitt Julia-Katharina Pfarr Jens Sommer Thomas R Kwapil Igor Nenadi 《Schizophrenia bulletin》2021,47(1):207
Numerous studies have implicated involvement of the hippocampus in the etiology and expression of schizophrenia-spectrum psychopathology, and reduced hippocampal volume is one of the most robust brain abnormalities reported in schizophrenia. Recent studies indicate that early stages of schizophrenia are specifically characterized by reductions in anterior hippocampal volume; however, studies have not examined hippocampal volume reductions in subclinical schizotypy. The present study was the first to examine the associations of positive, negative, and disorganized schizotypy dimensions with hippocampal subfield volumes in a large sample (n = 195) of nonclinically ascertained young adults, phenotyped using the Multidimensional Schizotypy Scale (MSS). Hippocampal subfields were analyzed from high-resolution 3 Tesla structural magnetic resonance imaging scans testing anatomical models, including anterior vs posterior regions and the cornu ammonis (CA), dentate gyrus (DG), and subiculum subfields separately for the left and right hemispheres. We demonstrate differential spatial effects across anterior vs posterior hippocampus segments across different dimensions of the schizotypy risk phenotype. The interaction of negative and disorganized schizotypy robustly predicted left hemisphere volumetric reductions for the anterior and total hippocampus, and anterior CA and DG, and the largest reductions were seen in participants high in negative and disorganized schizotypy. These findings extend previous early psychosis studies and together with behavioral studies of hippocampal-related memory impairments provide the basis for a dimensional neurobiological hippocampal model of schizophrenia risk. Subtle hippocampal subfield volume reductions may be prevalent prior to the onset of detectable prodromal clinical symptoms of psychosis and play a role in the etiology and development of such conditions. 相似文献
90.
David Hernndez-Gutirrez Francisco Muoz Jose Snchez-García Werner Sommer Rasha Abdel Rahman Pilar Casado Laura Jimnez-Ortega Javier Espuny Sabela Fondevila Manuel Martín-Loeches 《Social cognitive and affective neuroscience》2021,16(5):502
Natural use of language involves at least two individuals. Some studies have focused on the interaction between senders in communicative situations and how the knowledge about the speaker can bias language comprehension. However, the mere effect of a face as a social context on language processing remains unknown. In the present study, we used event-related potentials to investigate the semantic and morphosyntactic processing of speech in the presence of a photographic portrait of the speaker. In Experiment 1, we show that the N400, a component related to semantic comprehension, increased its amplitude when processed within this minimal social context compared to a scrambled face control condition. Hence, the semantic neural processing of speech is sensitive to the concomitant perception of a picture of the speaker’s face, even if irrelevant to the content of the sentences. Moreover, a late posterior negativity effect was found to the presentation of the speaker’s face compared to control stimuli. In contrast, in Experiment 2, we found that morphosyntactic processing, as reflected in left anterior negativity and P600 effects, is not notably affected by the presence of the speaker’s portrait. Overall, the present findings suggest that the mere presence of the speaker’s image seems to trigger a minimal communicative context, increasing processing resources for language comprehension at the semantic level. 相似文献