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971.
972.
Ulrich Leicht-Deobald Heike Bruch Luisa Bönke Amie Stevense Yan Fan Malek Bajbouj Simone Grimm 《Brain imaging and behavior》2018,12(5):1405-1418
Early life stress (ELS) affects stress- reactivity via limbic brain regions implicated such as hippocampus and amygdala. Social support is a major protective factor against ELS effects, while subjects with ELS experience reportedly perceive less of it in their daily life. The workplace, where most adults spend a substantial amount of time in their daily lives, might serve as a major resource for social support. Since previous data demonstrated that social support attenuates stress reactivity, we here used a psychosocial stress task to test the hypothesis that work-related social support modulates the effects of ELS. Results show decreased amygdala reactivity during stress in ELS subjects who report high levels of work- related social support, thereby indicating a signature for reduced stress reactivity. However, this effect was only observable on the neural, but not on the behavioral level, since social support had no buffering effect regarding the subjective experience of stress in daily life as well as regarding feelings of uncontrollability induced by the stress task. Accordingly, our data suggest that subjects with ELS experiences might benefit from interventions targeted at lowering their subjective stress levels by helping them to better perceive the availability of social support in their daily lives. 相似文献
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974.
Kurt Hahlweg Nina Heinrichs Annett Kuschel Heike Bertram Sebastian Naumann 《Child and adolescent psychiatry and mental health》2010,4(1):14
Background
Approximately 20% of children experience internalizing or externalizing DSM-IV-TR disorders. This prevalence rate cannot be reduced through treatment only. Effective preventive interventions are therefore urgently needed. The aim of the current investigation is to evaluate the two-year efficacy of the group Triple P parenting program administered universally for the prevention of child behavior problems. 相似文献975.
Heike Klsch Dieter Lütjohann Albert Tulke Ingemar Bjrkhem Marie Luise Rao 《Brain research》1999,818(1):403
Neurodegenerative disorders are characterized by a massive loss of nerve cells. The neuronal cell death is accompanied by an increased cholesterol release and conversion of cholesterol into the polar metabolite, 24-hydroxycholesterol (24-OH-Chol), appears to be an important mechanism in the central nervous system for eliminating cholesterol from the brain. We tested the influence of 24-OH-Chol on SH-SY5Y human neuroblastoma cells by recording cell morphology, Trypan blue exclusion, LDH-release into the culture medium, intracellular calcium and reactive oxygen species (ROS). The exposure of SH-SY5Y human neuroblastoma cells to 50 μM 24-OH-Chol led to a 90% loss in cell viability within 30 h, the LDH-release into the medium increased rapidly after 24 h, and after 24 to 30 h we found an elevation in intracellular calcium. These results show that, in a physiological concentration range, 24-OH-Chol damages neuronal cells, thus we speculate that this oxysterol may be involved in the etiology of neurodegenerative disease. 相似文献
976.
Sasa Stojadinovic Heike Höer Harald Eufinger Siegmar Reinert 《Oral and maxillofacial surgery》1999,3(5):279-282
After difficult endotracheal intubation in oral and maxillofacial surgery, esophageal or tracheal injuries can cause mediastinal, pericardial or cervicofacial soft tissue emphysema. If a patient has of thoracic pain after general anesthesia, mediastinal emphysema should be taken into consideration because of the possibility of subsequent life-threatening complications. Diagnosis can be established with computed tomography and fiberendoscopy.We present the diagnostic and therapeutic management of two patients. 相似文献
977.
Birgit Lohberger Michael Payer Beate Rinner Heike Kaltenegger Elisabeth Wolf Katharina Schallmoser Dirk Strunk Eva Rohde Andrea Berghold Karin Pekovits Angelika Wildburger Andreas Leithner Reinhard Windhager Norbert Jakse 《Journal of cranio-maxillo-facial surgery》2013,41(2):110-118
The purpose of this study was to analyse the potential of intraoral tissues as a source of mesenchymal stromal and progenitor cells (MSPCs) for usage in future cell-based therapy models.Cells were isolated from four different tissues harvested during oral surgery intervention: (1) bone explants from the posterior maxilla, (2) bone explants from the oblique line, (3) from the mandibular periosteum, and (4) from the dental pulp. Donor sites and tissues were evaluated in terms of their accessibility, donor-site morbidity and average time period until appearance of MSPC colonies. Cell characterization was performed by flow cytometry and evaluation of in vitro osteogenic, adipogenic and chondrogenic differentiation potential.Adherent cell colonies were isolated from tissues from all sites after 4–8 days. The cells showed characteristics of MSPCs, so they were expanded up to clinical scales and demonstrated multipotency. The lowest donor-site morbidity was observed in the posterior maxilla harvests, while the highest donor-site morbidity was associated with harvests from mandibular sites.All sites seem to be potential sources of mesenchymal stromal and progenitor cells for tissue engineering approaches. Therefore, harvest morbidity and patient acceptance should affect the choice of the appropriate site. 相似文献
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979.
Peter Saparin Heike Scherf Jean‐Jacques Hublin Peter Fratzl Richard Weinkamer 《Anatomical record (Hoboken, N.J. : 2007)》2011,294(1):55-67
The anisotropic arrangement of trabeculae in the proximal femur of humans and primates is seen as striking evidence for the functional adaptation of trabecular bone architecture. Quantitative evidence to demonstrate this adaptation for trabecular bone is still scarce, because experimental design of controlled load change is difficult. In this work, we use the natural variation of loading caused by a different main locomotor behavior of primates. Using high‐resolution computed tomography and advanced image analysis techniques, we analyze the heterogeneity of the architecture in four proximal femora of four primate species. Although the small sample number does not allow an interspecies comparison, the very differently loaded bones are well suited to search for common structural features as a result of adaptation. A cubic volume of interest of size (5 mm)3 was moved through the proximal femur and a morphometric analysis including local anisotropy was performed on 209 positions on average. The correlation of bone volume fraction (BV/TV) with trabecular number (Tb.N) and trabecular thickness (Tb.Th) leads to the suggestion of two different mechanisms of trabecular bone adaptation. Higher values of BV/TV in highly loaded regions of the proximal femur are due to a thickening of the trabeculae, whereas Tb.N does not change. In less loaded regions, however, lower values of BV/TV are found, caused by a reduction of the number of the trabeculae, whereas Tb.Th remains constant. This reduction in Tb.N goes along with an increase in the degree of anisotropy, indicating an adaptive selection of trabeculae. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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