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排序方式: 共有399条查询结果,搜索用时 31 毫秒
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New resuscitation guidelines were published by the International Liaison Committee on Resuscitation (ILCOR) in late 2005. Changes compared to earlier guidelines were made to the following topics: level of inspiratory oxygen concentration, intrapartum suctioning of meconium-stained amniotic fluid, target tidal volume during mechanical ventilation, and induced hypothermia following perinatal asphyxia. These new aspects were integrated into the resuscitation procedures of preterm and term infants and discussed separately. Meconium aspiration, duct-dependent congenital heart disease and respiratory distress syndrome require a particular problem-oriented approach in the operating and delivery room, on transport, and in the intensive care unit. Subsequently, the management of meconium aspiration, critical congenital heart disease and the initial management of preterm infants with a birth weight of less than 1,500 g are discussed in detail. 相似文献
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T Hoehn M William A R McPhaden H Stannigel E Mayatepek R M Wadsworth 《The European respiratory journal》2006,27(6):1311-1315
Abnormal growth and development of lymphatic pulmonary structures leads to severe hypoxia in congenital pulmonary lymphangiectasis (CPL). This case study aims to determine the cellular source and topographical distribution of the nitric oxide synthases in CPL. It studies the post mortem tissue of a term newborn with the clinical course and histological findings of CPL and three controls without pulmonary pathology. It was found that endothelial cells of pulmonary arteries and lymphatic structures stained significantly more for endothelial nitric oxide synthase protein in the CPL patient compared to the controls. The authors conclude that synthesis of endothelial nitric oxide synthase is upregulated in vascular and lymphatic endothelial cells in congenital pulmonary lymphangiectasis. 相似文献
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In the cortex only a few of the available NMDA receptors must be activated to evoke maximal release of adenosine. In fact, maximal adenosine release occurs at 30 μM NMDA, a concentration at which noradrenaline release is only 20% maximal. NMDA-evoked noradrenaline release appears to require the generation of propagated action potentials, while adenosine release does not. Noncompetitive block of NMDA-evoked release of adenosine, but not noradrenaline, can be overcome by increasing NMDA concentrations. The above findings are consistent with the possibility that there are spare receptors for NMDA-evoked adenosine release, but not for nor-adrenaline release. These spare receptors are not due to elevated levels of glycine in the vicinity of those NMDA receptors mediating adenosine release. Functionally, it appears that low level NMDA receptor activation provides a purinergic inhibitory threshold against higher level NMDA receptor mediated processes. This could provide inhibitory tone and selectivity for critical functions, such as learning, memory, and synaptic plasticity in the cortex. © 1993 Wiley-Liss, Inc. 相似文献
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Bojana Stefanovic Wolfram Schwindt Mathias Hoehn Afonso C Silva 《Journal of cerebral blood flow and metabolism》2007,27(4):741-754
The cerebrovascular coupling under neuronal nitric oxide synthase (nNOS) inhibition was investigated in alpha-chloralose anesthetized rats. Cerebral blood flow (CBF), cerebral blood volume (CBV), and blood oxygenation level dependent (BOLD) responses to electrical stimulation of the forepaw were measured before and after an intraperitoneal bolus of 7-nitroindazole (7-NI), an in vivo inhibitor of the neuronal isoform of nitric oxide synthase. Neuronal activity was measured by recording somatosensory-evoked potentials (SEPs) via intracranial electrodes. 7-Nitroindazole produced a significant attenuation of the activation-elicited CBF (P<10(-6)), CBV (P<10(-6)), and BOLD responses (P<10(-6)), without affecting the baseline perfusion level. The average DeltaCBF was nulled, while DeltaBOLD and DeltaCBV decreased to approximately 30% of their respective amplitudes before 7-NI administration. The average SEP amplitude decreased (P<10(-5)) to approximately 60% of its pretreatment value. These data describe a pharmacologically induced uncoupling between neuronal and hemodynamic responses to functional activation, and provide further support for the critical role of neuronally produced NO in the cerebrovascular coupling. 相似文献
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Anjali Ramaswamy Nina N. Brodsky Tomokazu S. Sumida Michela Comi Hiromitsu Asashima Kenneth B. Hoehn Ningshan Li Yunqing Liu Aagam Shah Neal G. Ravindra Jason Bishai Alamzeb Khan William Lau Brian Sellers Neha Bansal Pamela Guerrerio Avraham Unterman Victoria Habet Carrie L. Lucas 《Immunity》2021,54(5):1083-1095.e7
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Saleh A Wiedermann D Schroeter M Jonkmanns C Jander S Hoehn M 《NMR in biomedicine》2004,17(4):163-169
Brain inflammation contributes to the tissue injury caused by ischemic stroke. Macrophages as the most abundant inflammatory cell population in stroke lesions can be visualized using ultrasmall superparamagnetic iron oxide (USPIO) as a cell-specific contrast agent for magnetic resonance imaging (MRI). The aim of our present study was to delineate the inflammatory response during experimental cerebral infarction by means of USPIO-enhanced MRI and to correlate the spatial distribution of USPIO-induced MR signal alterations with cellular infiltration and iron deposition. To this end USPIOs were administered to Wistar rats 5 days after photothrombotic cerebral infarction. MR imaging at 7 T performed 24 h later displayed a rim-like signal loss around the infarction in the USPIO treated animals. On histological brain sections obtained from the same animals after MRI the distribution of iron and ED1+ phagocytes was in full spatial agreement with the signal loss seen on T2*-weighted images. Our study validates USPIO-enhanced MRI as an important tool for the noninvasive visualization of brain inflammation in stroke and other CNS pathologies. 相似文献
10.
Holger Hoehn Maria L. Rodriguez Thomas H. Norwood Clare L. Maxwell Uta Francke 《American journal of medical genetics. Part A》1978,2(3):253-266
The last decade has witnessed increasing application of human cytogenetic technology to prenatal chromosome analysis. However, unlike the rather uniform peripheral blood T-lymphocyte system which has provided most of our experience in human cytogenetics, long-term amniotic-fluid cell cultures display extreme cellular heterogeneity and disproportionate growth of certain cell types as a consequence of clonal amplification. When they enter cell culture, many of these cells are approching the terminal stages of their respective life spans and may have accumulated chromosomal aberrations. Concern about the possibility of true fetal mosaicism seems warranted chiefly in situations were multiple colonies display potentially viable aberrations. Clonal analysis, preferable of multiple clonal types, and attention to details of clonal morphology are likely to minimize diagnostic errors and undue apprehension resulting from mosaicism in amniotic-fluid cell cultures. 相似文献