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排序方式: 共有4180条查询结果,搜索用时 156 毫秒
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Hielke M. de Vries Hack Jae Lee Wayne Lam Rosa S. Djajadiningrat Sarah R. Ottenhof Eduard Roussel Bin Klaas Kroon Igle Jan de Jong Pedro Oliveira Hussain M. Alnajjar Maarten Albersen Asif Muneer Vijay Sangar Arie Parnham Benjamin Ayres Nick Watkin Simon Horenblas Martijn M. Stuiver Oscar R. Brouwer 《BJU international》2022,130(1):126-132
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Avni V. Patel Alia Rashid Frederick A. Jakobiec Daniel R. Lefebvre 《Orbit (Amsterdam, Netherlands)》2015,34(4):212-215
The orbital branch of the infraorbital artery, a key vascular structure that is not universally noted in orbital textbooks and atlases, is clinically significant, since injury to it can result in perioperative hemorrhage. We conducted a cadaver dissection to document its presence, measure its location, and evaluate it histopathologically. It was present in 8 of 9 orbits and was a mean distance of 16.6?mm (range 10–23) from the inferior orbital rim. In half of the specimens, there were 2 separate structures seen. Histopathology confirmed these structures to be neurovascular bundles. 相似文献
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Asif Jamil Giorgi Batsikadze Hsiao‐I. Kuo Raf L. J. Meesen Peter Dechent Walter Paulus Michael A. Nitsche 《Human brain mapping》2020,41(6):1644-1666
Transcranial direct current stimulation (tDCS) induces polarity‐ and dose‐dependent neuroplastic aftereffects on cortical excitability and cortical activity, as demonstrated by transcranial magnetic stimulation (TMS) and functional imaging (fMRI) studies. However, lacking systematic comparative studies between stimulation‐induced changes in cortical excitability obtained from TMS, and cortical neurovascular activity obtained from fMRI, prevent the extrapolation of respective physiological and mechanistic bases. We investigated polarity‐ and intensity‐dependent effects of tDCS on cerebral blood flow (CBF) using resting‐state arterial spin labeling (ASL‐MRI), and compared the respective changes to TMS‐induced cortical excitability (amplitudes of motor evoked potentials, MEP) in separate sessions within the same subjects (n = 29). Fifteen minutes of sham, 0.5, 1.0, 1.5, and 2.0‐mA anodal or cathodal tDCS was applied over the left primary motor cortex (M1) in a randomized repeated‐measure design. Time‐course changes were measured before, during and intermittently up to 120‐min after stimulation. ROI analyses indicated linear intensity‐ and polarity‐dependent tDCS after‐effects: all anodal‐M1 intensities increased CBF under the M1 electrode, with 2.0‐mA increasing CBF the greatest (15.3%) compared to sham, while all cathodal‐M1 intensities decreased left M1 CBF from baseline, with 2.0‐mA decreasing the greatest (?9.3%) from sham after 120‐min. The spatial distribution of perfusion changes correlated with the predicted electric field, as simulated with finite element modeling. Moreover, tDCS‐induced excitability changes correlated more strongly with perfusion changes in the left sensorimotor region compared to the targeted hand‐knob region. Our findings reveal lasting tDCS‐induced alterations in cerebral perfusion, which are dose‐dependent with tDCS parameters, but only partially account for excitability changes. 相似文献
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