An intra-subject investigation of the BOLD contrast mechanism in response to visual stimulation and breath hold at 1.5T, 3.0T and 7.0T: insight into the extravascular sensitivity, resolution-dependence and vascular origins of BOLD contrast
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Table 1 ΔR2,tot* (s) ΔR2,ext* (s) ΔR2,ext*/ΔR2,tot* HSR (ΔS/S)tot LSR (ΔS/S)tot LSR BH (ΔS/S)tot 1.5T -0.62±0.10 -0.28±0.07 0.45±0.13 5.3±2.4% 3.3±0.9% 1.5±0.9% 3.0T -0.74±0.05 -0.52±0.07 0.70±0.11 5.5±0.5% 4.0±1.0% 2.0±0.9% 7.0T -1.83±0.26 -1.68±0.25 0.92±0.19 6.0±0.5% 8.0±1.6% 3.2±1.1% Fig 1. Act. (z) maps An intra-subject investigation of the BOLD contrast mechanism in response to visual stimulation and breath hold at 1.5T, 3.0T and 7.0T: insight into the extravascular sensitivity, resolution-dependence and vascular origins of BOLD contrast
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تاریخ انتشار 2008