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961.
Shui-hua Yang MD Gui-dan He MD Meng-feng Liang MD Gui-chan Qin MD Yu-lan Pang MD Xue-qin Li MD Xin-yan Li MD Hong-wei Wei MD Ying-fei Wang MD 《Echocardiography (Mount Kisco, N.Y.)》2020,37(12):2152-2154
Vascular ring and sling are congenital anomalies of the vascular structure in the thorax with a prevalence of 2.4/10,000 live births. Double aortic arch (DAA), right aortic arch with left ductus arteriosus and aberrant left subclavian artery (RAA-ALSA), and pulmonary artery sling (PAS) are the three common types of vascular ring and sling. These anomalies can be isolated or accompanied by intracardiac malformation. The presence of both vascular ring and PAS is extremely rare. Here, we report a fetus who was prenatally diagnosed with PAS and RAA-ALS, and developed symptoms due to esophageal and airway compression after birth. 相似文献
962.
Qian Wang Dexiao Zhu Shuo Ping Chuangang Li Kunkun Pang Shaowei Zhu Jing Zhang Stefano Comai Jinhao Sun 《Journal of pineal research》2020,69(3):e12674
Melatonin (MLT) is widely used to treat sleep disorders although the underlying mechanism is still elusive. In mice, using wheel-running detection, we found that exogenous MLT could completely recover the period length prolonged by N-methyl-D-aspartate receptor (NMDAR) impairment due to the injection of the NMDAR antagonist MK-801, a preclinical model of psychosis. The analysis of the possible underlying mechanisms indicated that MLT could regulate the homeostatic state in the ventrolateral preoptic nucleus (VLPO) instead of the circadian process in the suprachiasmatic nucleus (SCN). In addition, our data showed that MK-801 decreased Ca2+-related CaMKII expression and CREB phosphorylation levels in the VLPO, and MLT could rescue these intracellular impairments but not NMDAR expression levels. Accordingly, Gcamp6 AAV virus was injected in-vivo to further monitor intracellular Ca2+ levels in the VLPO, and MLT demonstrated a unique ability to increase Ca2+ fluorescence compared with MK-801-injected mice. Additionally, using the selective melatonin MT2 receptor antagonist 4-phenyl-2-propionamidotetralin (4P-PDOT), we discovered that the pharmacological effects of MLT upon NMDAR impairments were mediated by melatonin MT2 receptors. Using electroencephalography/electromyography (EEG/EMG) recordings, we observed that the latency to the first nonrapid eye movement (NREM) sleep episode was delayed by MK-801, and MLT was able to recover this delay. In conclusion, exogenous MLT by acting upon melatonin MT2 receptors rescues sleep phase delayed by NMDAR impairment via increasing intracellular Ca2+ signaling in the VLPO, suggesting a regulatory role of the neurohormone on the homeostatic system. 相似文献
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966.
Do governing body and CSU nurses on clinical commissioning groups really lead a nursing agenda? Findings from a 2015 Survey of the Commissioning Nurse Leaders' Network Membership 下载免费PDF全文
967.
Since significant differences exist in imaging principle and parameters of different synthetic aperture radar (SAR) sensors, the detection of stable consistent features and accurate feature matching are difficult to implement in multi-sensor SAR image coregistration. To solve these problems, this study proposed a coregistration method based on stable convex corner point and double matching network. The stable convex corner points were detected from stable convex polygons, which were obtained by the proposed local stable extremal region extraction method, convex polygon fitting, and normalization. The double matching network was divided into coarse and fine matching. We utilized spatial relationships of the stable convex polygons to build a coarse matching network, and the fine matching network was formed by stable convex corner points. Precise matching was achieved with region features and spatial relations. Experimental results on multi-sensor SAR images showed that the proposed method had superior performance. 相似文献
968.
Achieving public and global health competencies: A teaching case study of Botswana's cervical cancer screening program 下载免费PDF全文
969.
Helen M. Ditz Andreas Nieder 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(25):7827-7832
It is unknown whether anatomical specializations in the endbrains of different vertebrates determine the neuronal code to represent numerical quantity. Therefore, we recorded single-neuron activity from the endbrain of crows trained to judge the number of items in displays. Many neurons were tuned for numerosities irrespective of the physical appearance of the items, and their activity correlated with performance outcome. Comparison of both behavioral and neuronal representations of numerosity revealed that the data are best described by a logarithmically compressed scaling of numerical information, as postulated by the Weber–Fechner law. The behavioral and neuronal numerosity representations in the crow reflect surprisingly well those found in the primate association cortex. This finding suggests that distantly related vertebrates with independently developed endbrains adopted similar neuronal solutions to process quantity.Birds show elaborate quantification skills (1–3) that are of adaptive value in naturalistic situations like nest parasitism (4), food caching (5), or communication (6). The neuronal correlates of numerosity representations have only been explored in humans (7–9) and primates (10–18), and they have been found to reside in the prefrontal and posterior parietal neocortices. In contrast to primates, birds lack a six-layered neocortex. The birds’ lineage diverged from mammals 300 Mya (19), at a time when the neocortex had not yet developed from the pallium of the endbrain. Instead, birds developed different pallial parts as dominant endbrain structures (20, 21) based on convergent evolution, with the nidopallium caudolaterale (NCL) as a high-level association area (22–26). Where and how numerosity is encoded in vertebrates lacking a neocortex is unknown. Here, we show that neurons in the telencephalic NCL of corvid songbirds respond to numerosity and show a specific code for numerical information. 相似文献
970.
Bone Marrow Assessment in Asymptomatic IgM Monoclonal Gammopathies – Reply to Varettoni et al 下载免费PDF全文
Roger G. Owen Guy Pratt Rebecca L. Auer Rita Flatley Charalampia Kyriakou Michael P. Lunn Francis Matthey Helen McCarthy Feargal P. McNicholl Saad M. Rassam Simon D. Wagner Matthew Streetly Shirley D'Sa the British Committee for Standards in Haematology 《British journal of haematology》2015,168(2):302-303