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131.
Altered interregional molecular associations of the serotonin transporter in attention deficit/hyperactivity disorder assessed with PET
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Thomas Vanicek Alexandra Kutzelnigg Cecile Philippe Helen L. Sigurdardottir Gregory M. James Andreas Hahn Georg S. Kranz Anna Höflich Alexander Kautzky Tatjana Traub‐Weidinger Marcus Hacker Wolfgang Wadsak Markus Mitterhauser Siegfried Kasper Rupert Lanzenberger 《Human brain mapping》2017,38(2):792-802
Altered serotonergic neurotransmission has been found to cause impulsive and aggressive behavior, as well as increased motor activity, all exemplifying key symptoms of ADHD. The main objectives of this positron emission tomography (PET) study were to investigate the serotonin transporter binding potential (SERT BPND) in patients with ADHD and to assess associations of SERT BPND between the brain regions. 25 medication‐free patients with ADHD (age ± SD; 32.39 ± 10.15; 10 females) without any psychiatric comorbidity and 25 age and sex matched healthy control subjects (33.74 ± 10.20) were measured once with PET and the highly selective and specific radioligand [11C]DASB. SERT BPND maps in nine a priori defined ROIs exhibiting high SERT binding were compared between groups by means of a linear mixed model. Finally, adopted from structural and functional connectivity analyses, we performed correlational analyses using regional SERT binding potentials to examine molecular interregional associations between all selected ROIs. We observed significant differences in the interregional correlations between the precuneus and the hippocampus in patients with ADHD compared to healthy controls, using SERT BPND of the investigated ROIs (P < 0.05; Bonferroni corrected). When correlating SERT BPND and age in the ADHD and the healthy control group, we confirmed an age‐related decline in brain SERT binding in the thalamus and insula (R2 = 0.284, R2 = 0.167, Ps < 0.05; Bonferroni corrected). The results show significantly different interregional molecular associations of the SERT expression for the precuneus with hippocampus in patients with ADHD, indicating presumably altered functional coupling. Altered interregional coupling between brain regions might be a sensitive approach to demonstrate functional and molecular alterations in psychiatric conditions. Hum Brain Mapp 38:792–802, 2017. © 2016 Wiley Periodicals, Inc. 相似文献
132.
133.
Three new isocoumarin derivatives ( 2- 4) were isolated together with monocerin ( 1) from Microdochium bolleyi, an endophytic fungus from Fagonia cretica, a herbaceous plant of the semiarid coastal regions of Gomera. Compounds 2 and 3 are both 12-oxo epimers of 1, and 4 is a ring-opened derivative of 1. The structures were elucidated by detailed spectroscopic analysis and comparison with reported data. The absolute configurations were determined by a modified Mosher's method. Compounds 1, 3, and 4 showed good antifungal, antibacterial, and antialgal activities against Microbotryum violaceum, Escherichia coli, Bacillus megaterium, and Chlorella fusca. Compound 2 was moderately antifungal and antialgal. 相似文献
134.
Ohne Zusammenfassung
Im Auszug vorgetragen von Dr. R. Kraus am IX. internat. Congresse für Hygiene und Demographie (Madrid April 1898). 相似文献
135.
David M. Goldenberg Helmut Schmidt Siegfried Witte 《Journal of cancer research and clinical oncology》1967,69(4):316-325
Zusammenfassung Das Wachstumsverhalten zweier in das Gehirn von Goldhamstern implantierter menschlicher Tumoren (H. Ad. Nr. 1 und H. S. Nr. 1) wurde untersucht. Bei allen Tieren konnte ein Tumorwachstum histologisch nachgewiesen werden. Cortisonvorbehandlung der Wirtstiere begünstigte bei H. Ad. Nr. 1 die Tumorausbreitung und führte frühzeitiger zum Tode. Das intracerebrale Tumorwachstum führte jedoch auch unabhängig von der Wirtsvorbehandlung bei allen Tieren zum Tode innerhalb von 4 Wochen nach der Transplantation. Beide Geschwulst-typen wuchsen am besten in den liquorhaltigen Räumen, weniger in der Hirnsubstanz. Die Bevorzugung der Meningen durch beide Tumortypen entspricht der allgemeinen Erfahrung über die cerebrale Metastasierung entdifferenzierte Sarkome und Adenocarcinome.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Summary The growth behavior of two human tumors (H. Ad. No. 1 and H. S. No. 1) transplanted to the hamster brain has been studied. Tumor growth could be histologically verified in all animals inoculated. Cortisone-conditioning of the host increased tumor expansion and resulted in an earlier and more rapid death rate in the H. Ad. No. 1 group. Regardless of tumor or host-conditioning employed, all animals succumbed to intracerebral tumor growth by the end of the fourth week post transplantation. Both tumor types grew better in the ventricles and subarachnoid space than in the brain tissue itself. The predilection of these two tumor types for the meninges confirms our clinical knowledge on the pattern of cerebral metastasis of dedifferentiated sarcomas and adenocarcinomas.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
136.
Pre‐clinical heterotopic intrathoracic heart xenotransplantation: a possibly useful clinical technique
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Bruno Reichart Stefan Buchholz Fabian Werner Isabelle Lutzmann Michael Schmoeckel Andreas Bauer Michael Thormann Martin Langenmayer Nadja Herbach Heike Pohla Rudolf Herzog Christopher G. A. McGregor David Ayares Eckhard Wolf Nikolai Klymiuk Andrea Baehr Alexander Kind Christian Hagl Ute Ganswindt Claus Belka Paolo Brenner 《Xenotransplantation》2015,22(6):427-442
137.
BACKGROUND: Before surgical simulators can be implemented for assessment of surgical training, their construct validity should be assessed. METHODS: Nine novices (NOV), nine medical students (MS), and nine residents (RES) underwent a laparoscopic skills training on the virtual reality (VR) simulator Lap Mentor. Assessment of laparoscopic skill was based on parameters measured by the computer system before and after training. RESULTS: Significant difference existed between RES and NOV at seven of nine tasks before training on the VR simulator. After the training in some tasks significant differences were observed between the experienced group (RES) and the nonexperienced groups (MS and NOV) or between medical groups (RES and MS) and nonmedical group (NOV). CONCLUSIONS: Performance parameters of the Lap-Mentor can be used to distinguish between subjects with varying laparoscopic experience. 相似文献
138.
Christian Hagl Nawid Khaladj Donald J Weisz Ning Zhang Lan Jun Guo Carol A Bodian David Spielvogel Randall B Griepp 《European journal of cardio-thoracic surgery》2002,22(4):510-516
OBJECTIVE: This review was undertaken to determine whether high intracranial pressure (ICP) during reperfusion after hypothermic circulatory arrest (HCA) correlates with evidence of suboptimal cerebral protection in a chronic porcine model. METHODS: In concurrent studies of cerebral protection, 48 control pigs (24-31 kg) underwent 90 min of HCA at 20 degrees C using a strictly standardized protocol. Hemodynamic measurements, ICP and neurophysiological data (EEG, SSEP) were assessed before HCA and until 3 h postoperatively. ICP was measured using a Codman microtip catheter inserted directly into brain parenchyma. Neurological/behavioral evaluation (9=full recovery) was carried out daily through postoperative day (POD) 3. RESULTS: There were no significant hemodynamic or metabolic differences between individual animals. ICP (mmHg) increased significantly for the first 3 h after HCA: from baseline levels of 6.2+/-2.1 to 10+/-2.6 at 1 h, 11+/-3.2 at 2 h and 10+/-3.6 mmHg at 3 h; P<0.001 for the trend. EEG recovery 3 h after HCA was observed in 13 animals (27%), and correlated with lower ICP during reperfusion (P<0.001): with each 1 mmHg increase in ICP at 3 h, the odds of early EEG recovery decreased by a factor of 0.72. Lower ICP during reperfusion was also significantly associated with higher behavioral scores on POD 1 and 2, P<0.001. CONCLUSIONS: A significant rise in ICP may help explain the prolonged obtundation and confusion often seen clinically after HCA. If these small but consistent increases in ICP contribute to rather than reflect ischemic neuronal damage, simple maneuvers to reduce ICP may improve cerebral recovery after HCA. 相似文献
139.
Feasibility of navigated resection of liver tumors using multiplanar visualization of intraoperative 3-dimensional ultrasound data 总被引:2,自引:0,他引:2
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BACKGROUND: Intraoperative ultrasound is widely used in liver surgery, but primarily for diagnostic purposes. We have developed and evaluated a system for navigated liver resections using on intraoperatively acquired 3-dimensional (3D) ultrasound data. METHODS: Navigation technique based on 3D ultrasound and an optical tracking system. Accuracy of the system was validated experimentally in a tumor model. Subsequently, clinical application was evaluated in 54 patients for resection of central liver tumors. Clinical feasibility and accuracy of the navigation technique were assessed with respect to practicability, adequacy of visualization, and precision of navigated resection (free margin). RESULTS: Evaluation of the system in the tumor model showed a significant increase of the accuracy of navigated resections compared with conventional resection (P < 0.05). Clinical application of 3D ultrasound-based navigation was feasible in 52 of 54 patients. Sufficient visualization was obtained with 2 orthogonal section planes. This navigation strategy provided complete anatomic orientation and accurate position control of surgical instruments. Mean histologic resection margin was 9 mm with a maximum deviation of 8 mm from the planned virtual resection margins. CONCLUSIONS: Optoelectronic navigation with section mode visualization in 2 orthogonal planes does sufficiently display intraoperative 3D data and enables accurate ultrasound-based navigation of liver resections. 相似文献
140.
Chlodwig Kirchhoff Peter Biberthaler Wolf E Mutschler Eugen Faist Marianne Jochum Siegfried Zedler 《Critical care (London, England)》2009,13(3):R88-11